Refining And Characterizing 

Heat Release Rates From 

Electrical Enclosures During 

Fire (RACHELLE-FIRE) 

Volume 1: 

Peak Heat Release Rates and

Effect of Obstructed Plume

Draft Report for Comment

U.S. Nuclear Regulatory Commission Electric Power Research Institute

Office of Nuclear Regulatory Research 3420 Hillview Avenue

Washington, D.C. 20555-0001 Palo Alto, CA 94304-1338

NUREG-2178, Vol. 1 EPRI 3002005578
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Refining And Characterizing 

Heat Release Rates From 

Electrical Enclosures During 

Fire (RACHELLE-FIRE) 

Volume 1: 

Peak Heat Release Rates and

Effect of Obstructed Plume

Draft Report for Comment

April 2015

U.S. Nuclear Regulatory Commission Electric Power Research Institute (EPRI)

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Washington, D.C. 20555-0001 Palo Alto, CA 94304-1338

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NUREG-2178, Vol. 1 EPRI 3002005578
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iii 

1 ABSTRACT 

2 

3 The Refining And Characterizing Heat Release Rates From Electrical Enclosures During Fire 

4 (RACHELLE-FIRE) program involves a working group of experienced fire protection and fire 

5 probabilistic risk assessment researchers and practitioners focused on enhancing the 

6 methodology used to model electrical enclosure fires in nuclear power plants (NPPs). This 

7 report documents the results from the working group’s efforts to develop technical information in 

8 three areas: (1) classification of electrical enclosures in terms of function, size, contents, and 

9 ventilation, (2) determination of peak heat release rate (HRR) probability distributions 

10 considering specific electrical enclosure characteristics, and (3) development of a method to 

11 account for the impact of the enclosure on the vertical thermal zone of influence (ZOI) above the 

12 enclosure during fire. 

13 

14 Electrical enclosures have been classified in classification groups based on their electrical 

15 function, contents, and size. Most power enclosures, such as switchgear, load centers, motor 

16 control centers, battery chargers, and power inverters, are grouped based on their function. 

17 Other electrical enclosures are classified as small, medium, and large enclosures based on their 

18 volumetric size. The classification is primarily based on the size because it can be easily 

19 assessed by visual inspection during walkdowns without opening the electrical enclosure. 

20 Distinctions based on conductor wiring insulation type (thermoplastic versus thermoset) and 

21 open versus closed door configurations have been retained for certain enclosure groupings. 

22 Peak HRR values can be refined based on visual inspection of the interior of the enclosures if 

23 fuel type, fuel quantity, and cable bundling arrangement can be expected to limit fire growth. 

24 

25 Peak HRR distributions for the different classification groups have been developed. These 

26 distributions are based on the results of different experimental programs intended to measure 

27 the HRR associated with fires in electrical enclosures. The working group evaluated the 

28 configuration factors in these fire tests and compared them with the actual configuration of 

29 electrical enclosures used in commercial NPPs and the available plant fire event experience. 

30 The resulting probability distributions are intended to map the configurations of the electrical 

31 enclosures in operation at the plant with the experimental factors evaluated during the test 

32 programs. As a result, HRR probability distributions are available for a wide range of electrical 

33 enclosure types and configurations. 

34 

35 In order to provide a comprehensive characterization of electrical enclosure fires, the working 

36 group evaluated the temperature characteristics of fire plumes associated with these events 

37 using the Fire Dynamics Simulator (FDS) program. Computer simulations of various enclosure 

38 configurations were developed for evaluating the fire burning inside electrical enclosures and 

39 the fire plume temperature characteristics that would be generated. Based on this research, 

40 new fire plume temperature profiles reflecting the obstructed nature of fire plumes generated 

41 from fires inside electrical enclosures are provided. 

42 

43 Finally, examples, consolidating the information described in this report, are provided. The 

44 examples have been selected and designed to illustrate how to incorporate the information 

45 documented in this report into existing approaches for modeling fires in electrical enclosures. 

46 

47 

v 

CONTENTS 

ABSTRACT ................................................................................................................................. iii

CONTENTS .................................................................................................................................. v

FIGURES ..................................................................................................................................... ix

TABLES ..................................................................................................................................... xiii

EXECUTIVE SUMMARY ............................................................................................................ xv

EPRI PERSPECTIVE ................................................................................................................ xix

PREFACE .................................................................................................................................. xxi

CITATIONS .............................................................................................................................. xxiii

ACKNOWLEDGMENTS ........................................................................................................... xxv

ACRONYMS ........................................................................................................................... xxvii

1 INTRODUCTION ............................................................................................................ 1-1

1.1 Background ........................................................................................................ 1-1

1.2 Approach ............................................................................................................ 1-2

1.3 Scope and Terminology ..................................................................................... 1-4

1.4 Objectives ........................................................................................................... 1-5

1.5 Report Organization ........................................................................................... 1-6

2 OVERVIEW OF THE PROCESS ................................................................................... 2-1

2.1 Classification of Electrical Enclosures ................................................................ 2-1

2.1.1 Review of Existing Guidance .................................................................. 2-1

2.1.2 Understanding the Fire Hazards Associated with Different 

Electrical Enclosures .............................................................................. 2-2

2.2 Process Used in Developing the HRR Distributions ........................................... 2-4

2.2.1 Literature Review .................................................................................... 2-4

2.2.2 Identification of Influencing Factors ........................................................ 2-5

2.2.3 Calibration Exercise ................................................................................ 2-6

2.2.4 Assessment of Electrical Enclosure Heat Release Rates ...................... 2-8

2.2.5 Building Consensus ................................................................................ 2-8

2.2.6 Ensuring Consistency and Applicability .................................................. 2-8

2.2.7 Finalizing the Consensus ...................................................................... 2-11

2.3 Method for Characterizing Electrical Enclosure Fire Plumes ........................... 2-11

3 CLASSIFICATION OF ELECTRICAL ENCLOSURES ................................................. 3-1

3.1 Functionally Based Enclosure Groups ............................................................... 3-3

3.1.1 Group 1: Switchgear and Load Centers ................................................. 3-3

3.1.2 Group 2: Motor Control Centers (MCCs) and Battery Chargers ............. 3-4

3.1.3 Group 3: Power Inverters........................................................................ 3-7

3.2 Group 4: All Other Electrical Enclosures ............................................................ 3-8

3.2.1 Assignment Based on Physical Size ...................................................... 3-9

3.2.1.1 Group 4a: Large Enclosures ....................................................... 3-9

3.2.1.2 Group 4b: Medium Enclosures ................................................. 3-11

3.2.1.3 Group 4c: Small Enclosures ..................................................... 3-12

3.2.2 Assignment Based on Fuel Loading Characteristics ............................ 3-13

4 PEAK HEAT RELEASE RATES FOR ELECTRICAL ENCLOSURES ......................... 4-1

4.1 Practice for Establishing Fire Diameter .............................................................. 4-4

4.2 Special Fuel Loading Configurations .................................................................. 4-7

4.2.1 Special Case 1: No Ignition Sources Present ......................................... 4-7
vi 

4.2.2 Special Case 2: Cables Enclosed in Conduits ........................................ 4-8

4.2.3 Special Case 3: Metal Enclosed Wire-Ways and Switch/Device 

Covers .................................................................................................. 4-10

5 Correlation of Obstructed Plume Models with Heskestad Plume 

Predictions .................................................................................................................... 5-1

5.1 Assumptions and Limitations .............................................................................. 5-1

5.1.1 Fire Dynamics Simulator ......................................................................... 5-1

5.1.2 Zone of Influence Applicability ................................................................ 5-2

5.1.3 Flame Height .......................................................................................... 5-3

5.1.4 Types of Obstructions ............................................................................. 5-3

5.1.5 Other Applicability Limitations ................................................................. 5-3

5.2 Technical Approach ............................................................................................ 5-4

5.2.1 Review of Past Studies ........................................................................... 5-5

5.2.2 Plume Theory ......................................................................................... 5-5

5.2.2.1 Plume Scaling ............................................................................. 5-5

5.2.2.2 Heskestad Plume Temperature .................................................. 5-6

5.2.3 The FDS Simulation Parameters ............................................................ 5-6

5.2.3.1 Heat Release Rate (HRR) .......................................................... 5-7

5.2.3.2 Fire Source Diameter .................................................................. 5-7

5.2.3.3 Obstruction Configuration ........................................................... 5-7

5.2.3.4 Enclosure Configurations ............................................................ 5-8

5.2.3.5 FDS Simulation Matrix ................................................................ 5-9

5.2.3.6 Simulation Compartment .......................................................... 5-10

5.2.3.7 Temperature Measurement Plane ............................................ 5-10

5.2.4 Preliminary FDS Simulations ................................................................ 5-11

5.2.4.1 No Obstruction – Baseline ........................................................ 5-11

5.2.4.2 Flat Plate Obstruction ............................................................... 5-14

5.2.4.3 Arch Obstruction ....................................................................... 5-16

5.2.4.4 Three-Wall Obstruction ............................................................. 5-17

5.2.4.5 Statistical Analysis .................................................................... 5-19

5.3 FDS Simulation Results ................................................................................... 5-19

5.3.1 Analysis of Non-Conservative Results .................................................. 5-20

5.3.2 Obstruction Configuration ..................................................................... 5-22

5.3.3 Fire Source Diameter ............................................................................ 5-23

5.3.4 Heat Release Rate ............................................................................... 5-24

5.3.5 Fire Source Elevation ........................................................................... 5-25

5.3.6 Statistical Analysis ................................................................................ 5-26

5.3.7 Summary of Results ............................................................................. 5-27

5.3.7.1 Bias and Uncertainty ................................................................. 5-29

5.3.7.2 Sensitivity to Center Openings on the Obstruction ................... 5-31

5.3.7.3 Sensitivity to Fire Orientation .................................................... 5-32

5.3.7.4 Sensitivity to Obstructions with a Soffit ..................................... 5-33

5.3.7.5 Sensitivity to Thickness of Steel Enclosure .............................. 5-34 

5.3.8 Horizontal Zone of Influence ................................................................. 5-35

5.3.8.1 Existing Definition of Horizontal ZOI ......................................... 5-35

5.3.8.2 Horizontal Plume Shift ZOI ....................................................... 5-37

5.3.8.3 Recommendations .................................................................... 5-40

6 CORRECTION FOR ZONE OF INFLUENCE DUE TO OBSTRUCTED 

PLUME EFFECT ............................................................................................................ 6-1

6.1 Assessment of FDS Simulation Results ............................................................. 6-1

6.2 Prediction of ZOI Correction ............................................................................... 6-1
vii 

6.2.1 Temperature Rise (Example 1) ............................................................... 6-1

6.2.2 Zone of Influence (Example 2) ................................................................ 6-2

6.2.3 Zone of Influence Sensitivity (Example 3) .............................................. 6-4

6.2.4 Fire Protection SDP Application (Example 4) ......................................... 6-5

6.2.5 Fire PRA Application (Example 5) .......................................................... 6-6

6.3 Plume Temperature and ZOI Corrections .......................................................... 6-7

6.4 Application of the Correction .............................................................................. 6-8

7 SUMMARY, CONCLUSIONS, AND FUTURE RESEARCH .......................................... 7-1

7.1 Classification of Electrical Enclosures ................................................................ 7-2

7.2 Peak Heat Release Rate Probability Distributions ............................................. 7-2

7.3 Obstructed Plume Analysis ................................................................................ 7-5

7.4 Example Applications ......................................................................................... 7-5

7.5 Future Research ................................................................................................. 7-5

8 REFERENCES ............................................................................................................... 8-1

APPENDIX A WG MEMBERS, NON-WG CONTRIBUTORS, AND FACILITATOR 

RESUMES ......................................................................................................... A-1

APPENDIX B OVERVIEW OF WORKING GROUP ACTIVITIES ........................................... B-1

APPENDIX C PHOTOGRAPHS SUPPORTING CLASSIFICATION OF ELECTRICAL 

ENCLOSURES ................................................................................................. C-1

APPENDIX D ELECTRICAL CABINET HEAT RELEASE RATE DATA ANALYSIS ............. D-1

APPENDIX E OBSTRUCTED PLUME FIRE MODELING RESULTS ..................................... E-1

APPENDIX F EXAMPLES OF ENCLOSURE FIRE ANALYSIS .............................................. F-1

APPENDIX G FIRE MODELS, INPUT DATA FILES, AND ADDITIONAL SUPPORTING 

INFORMATION .................................................................................................. CD

ix 

FIGURES 

Figure 2-1 Fire Size/Intensity Calibration (0 to 40 kW) ........................................................ 2-7

Figure 2-2 Fire Size/Intensity Calibration (50 to 1000 kW) .................................................. 2-7

Figure 2-3 HELEN-FIRE Test No. 68 ................................................................................ 2-11

Figure 3-1 Switchgear and Load Center .............................................................................. 3-4

Figure 3-2 A Typical Vertical MCC Channel ........................................................................ 3-5

Figure 3-3 A Typical Bank of MCC Cabinets ....................................................................... 3-6

Figure 3-4 A Typical Battery Charger .................................................................................. 3-7

Figure 3-5 A Typical Inverter Cabinet (Exterior – Left, Interior – Right) ............................... 3-8

Figure 3-6 Large Enclosures (Open) ................................................................................. 3-10

Figure 3-7 Large Enclosures (Closed) ............................................................................... 3-10

Figure 3-8 Medium Enclosures .......................................................................................... 3-11

Figure 3-9 Small Enclosures (Note: top left enclosure may be well-sealed) ...................... 3-12

Figure 3-10 Two “Very Low Fuel Loading” Enclosures ........................................................ 3-14

Figure 3-11 Large Enclosure (Closed and Open Configurations): Example of a 

“Low Fuel Loading” Subgroup .......................................................................... 3-16

Figure 4-1 A Graphical Representation of the Data in Table 4-3 ......................................... 4-6

Figure 4-2 Cropped Photo of Electrical Enclosure with Bundled Panel Wiring and 

Cable, Limited Combustible Loading, and No Ignition Sources ......................... 4-8

Figure 4-3 Photograph of LFMC (left) and FMT (right) Within Electrical Enclosure ........... 4-10

Figure 4-4 Photograph of Metal Enclosed Wire-Ways Within Electrical 

Enclosure (MCB) .............................................................................................. 4-10

Figure 4-5 Photograph of Switch/Devices Cover (Labeled B) Within an 

Electrical Enclosure .......................................................................................... 4-11

Figure 4-6 An Example of Non-Enclosed Wire-Ways That Would Not Qualify 

as Metal Enclosed Wire-Ways.......................................................................... 4-12

Figure 4-7 An Example of Substantially Ventilated Switch and/or Device Covers 

That Would Not Qualify for Reduction .............................................................. 4-13

Figure 5-1 Obstruction Geometries: Flat Plate, Arch, Three Walls ...................................... 5-8

Figure 5-2 Simulation Fire Source Elevations: 0.3048 m, 1.143 m, 1.9812 m ..................... 5-8

Figure 5-3 Obstruction Configurations: Flat Plate, Arch, and Three Walls .......................... 5-9

Figure 5-4 Simulation Compartment .................................................................................. 5-10

Figure 5-5 Slice File FDS Simulation Temperature Measurements ................................... 5-11

Figure 5-6 a) 200 kW, 0.6 m (diameter), 1.1 m (elevation) and b) 1000 kW, 

0.9 m (diameter), 2 m (elevation) – Non-Obstructed Geometry ....................... 5-12

Figure 5-7 HRR vs. Time, Unobstructed Simulation – 200 kW, 0.6 m (diameter), 

1.1 m (elevation) ............................................................................................... 5-13

Figure 5-8 HRR vs. Time, Unobstructed Simulation – 1000 kW, 0.9 m (diameter), 

2 m (elevation) .................................................................................................. 5-13

Figure 5-9 Temperature vs. Elevation Above Floor, Unobstructed Simulation – 

200 kW, 0.6 m (diameter), 1.1 m ( elevation) and 1000 kW, 

0.9 m (diameter), 2 m (elevation) ..................................................................... 5-14

Figure 5-10 a) 200 kW, 0.6 m (diameter), 1.1 m (elevation) and b) 1000 kW, 

1.2 m (diameter), 2 m (elevation) – Plate Obstruction ...................................... 5-14
x 

Figure 5-11 Temperature vs. Time, Flat Plate – 200 kW, 0.6 m (diameter), 

2 m (elevation) – Elevations Above the Obstruction ......................................... 5-15

Figure 5-12 Temperature vs. Elevation Above Floor, Flat Plate Obstruction – 

200 kW, 0.6 m (diameter), 1.1 m ( elevation) and 1000 kW, 

1.2 m (diameter), 2 m (elevation) ..................................................................... 5-16

Figure 5-13 a) 200 kW, 0.6 m (diameter), 1.1 m (elevation) and b) 1000 kW, 

1.2 m (diameter), 2 m (elevation) – Arch Obstruction ....................................... 5-16

Figure 5-14 Temperature vs. Height Above Floor – Arch Obstruction – 200 kW, 

0.6 m (diameter), 1.1 m (elevation) and 1000 kW, 1.2 m (diameter), 

2 m (elevation) .................................................................................................. 5-17

Figure 5-15 a) 200 kW, 0.6096 m (diameter), 1.1 m (elevation) and b) 1000 kW, 

1.2 m (diameter), 2 m (elevation) – Three-Wall Obstruction ............................ 5-18

Figure 5-16 Temperature vs. Height Above Floor – Three-Wall Obstruction – 200 kW, 

0.6 m (diameter), 1.1 m (elevation) and 1000 kW, 1.2 m (diameter), 

2 m (elevation) .................................................................................................. 5-18

Figure 5-17 Unobstructed versus Obstructed Plume Temperatures ................................... 5-20

Figure 5-18 a) Three-Wall Obstruction, 500 kW, 0.3 m b) No Obstruction, 

500 kW, 0.3 m .................................................................................................. 5-21

Figure 5-19 a) Three-Wall Obstruction, 1000 kW, 1.2192 m b) No Obstruction, 

1000 kW, 1.2 m ................................................................................................ 5-22

Figure 5-20 Unobstructed versus Obstructed Plume Temperatures – Different 

Geometries ....................................................................................................... 5-22

Figure 5-21 Plume Flows Subject to Different Obstruction Geometries: a) Flat Plate, 

 b) Arch, c) Three-Wall, d) Unobstructed ........................................................... 5-23

Figure 5-22 Unobstructed versus Obstructed Plume Temperatures – Different 

Fire Source Diameters...................................................................................... 5-24

Figure 5-23 Unobstructed versus Obstructed Plume Temperatures – Different HRRs ....... 5-25

Figure 5-24 Unobstructed versus Obstructed Plume Temperatures – Different 

Fire Source Elevations ..................................................................................... 5-26

Figure 5-25 Obstruction Effect on Plume Proportionality Constant ..................................... 5-28

Figure 5-26 Unobstructed versus Obstructed Plume Temperatures – Bias and 

 Uncertainty ....................................................................................................... 5-30

Figure 5-27 Heskestad versus Unobstructed Plume Temperatures – Bias and 

 Uncertainty ....................................................................................................... 5-30

Figure 5-28 Heskestad versus Obstructed Plume Temperatures – Bias and 

 Uncertainty ....................................................................................................... 5-31

Figure 5-29 a) Vertically Oriented Fire Source, b) Fire Source Located Along the 

 Cabinet Wall Surfaces ...................................................................................... 5-33

Figure 5-30 Top Obstruction with a Soffit ............................................................................ 5-34

Figure 5-31 Unobstructed vs. Obstructed Plume Temperatures – Soffit Sensitivity ............ 5-34

Figure 5-32 Unobstructed vs. Obstructed Plume Temperatures – Enclosure 

Thickness Sensitivity ........................................................................................ 5-35

Figure 5-33 SDP Ball and Column ....................................................................................... 5-36

Figure 5-34 Obstruction Plume Shift .................................................................................... 5-37

Figure 5-35 Determination of Horizontal Plume Shift ........................................................... 5-38

Figure 5-36 Comparison of Horizontal ZOI Resulting from Plume Shift to Thermal 

 Radiation Exposure .......................................................................................... 5-39

Figure 5-37 Maximum Angle from Horizontal Plume Shift ................................................... 5-40

Figure 5-38 Recommended ZOI for an Electrical Enclosure Fire a) Without Top 

 Obstruction Credit, and b) with Top Obstruction Credit .................................... 5-41
xi 

Figure 6-1 Unobstructed and Obstructed Temperature Predictions .................................... 6-2

Figure 6-2 Vertical Plume ZOI ............................................................................................. 6-3

Figure 6-3 ZOI Difference for Obstructed and Unobstructed Plume Flows Using 

Heskestad Fire Plume Correlation...................................................................... 6-4

Figure 6-4 Example 4, Reduction in Vertical ZOI Due to Obstructed Plume Credit ............. 6-6

Figure 6-5 NFPA 805 Example Reduction of Vertical ZOI ................................................... 6-7

xiii 

TABLES 

Table 3-1 Distinguishing Characteristics for Default versus Low Fuel Loading 

Conditions ........................................................................................................ 3-17

Table 4-1 Peak HRR Distributions for Functionally Based Classification 

Groups 1, 2, and 3 Enclosures ........................................................................... 4-2

Table 4-2 Peak Heat Release Rate Distributions for Classification Group 4 

(All Other) Electrical Enclosures ......................................................................... 4-3

Table 4-3 Range of Fire Diameters as a Function of Fire Intensity (HRR) That 

Remain Within the Validation Range for the Plume Correlations ....................... 4-5

Table 4-4 Minimum and Maximum Fire Diameter Values for the 98th Percentile 

HRR Values Cited in Tables 4-1 and 4-2 ........................................................... 4-6

Table 5-1 FDS Obstructed Plume Simulation Test Matrix .................................................. 5-9

Table 5-2 Bias and Uncertainty of Obstructed and Unobstructed Plume 

Temperature Rise ............................................................................................. 5-29

Table 5-3 Bias and Uncertainty of Obstructed (with Center Opening) and 

Unobstructed Plume Temperature Rise ........................................................... 5-32

Table 6-1 Example 2 ZOI Calculations ............................................................................... 6-3

Table 7-1 Peak Heat Release Rate Distributions for Electrical Enclosures ........................ 7-4

xv 

1 EXECUTIVE SUMMARY 

2 

3 During the last decade, a number of commercial nuclear power plants (NPPs) have been 

4 developing fire probabilistic risk assessments (fire PRAs) to support risk-informed applications, 

5 including a voluntary transition from a deterministic fire protection program to a risk6 informed/performance-based (RI/PB) program in accordance with National Fire Protection 

7 Association (NFPA) Standard 805, 2001 Edition. Most fire PRAs are based on methods and 

8 data described in NUREG/CR-6850 (EPRI 1011989), which was developed by a joint effort of 

9 both the Nuclear Regulatory Commission’s Office of Nuclear Regulatory Research (NRC-RES) 

10 and the Electric Power Research Institute (EPRI). The wide application of this methodology has 

11 identified technical areas where additional research and data could better characterize the fire 

12 risks representing as-built plant conditions. 

13 

14 One important element supporting fire PRAs and other performance-based approaches is the 

15 estimation of the fire hazard using mathematical fire models (i.e., “fire modeling”). Fire modeling 

16 is used to support fire PRA developments to determine the effects of fire hazards on plant risk. 

17 For most fire modeling applications, the fire’s heat release rate (HRR) is the most critical and 

18 difficult-to-predict parameter in characterizing the fire hazard. Specific to commercial NPP 

19 applications, the characterization of HRRs in electrical enclosures has been identified as a key 

20 technical area requiring additional research. In order to address this need, the NRC-RES and 

21 EPRI initiated the Refining And Characterizing Heat Release Rates From Electrical Enclosures 

22 During Fire (RACHELLE-FIRE) program. 

23 

24 The RACHELLE-FIRE program involves a working group of experienced fire protection and fire 

25 probabilistic risk assessment researchers and practitioners focused on reaching a consensus in 

26 estimating the peak HRR distributions for electrical enclosures used in NPPs. Based on the 

27 efforts of the working group, new methods and data have been developed in three specific 

28 areas: 

29 

30  Classification of electrical enclosures in terms of function, size, contents, and ventilation, 

31  Determination of peak HRR probability distributions considering specific electrical 

32 enclosure characteristics, and 

33  Development of a correction method to the vertical thermal zone of influence (ZOI) 

34 above the enclosure during fire. 

35 

36 Examples of fire modeling applications are included to show the differences between the current 

37 approach and the new HRR values including the effect of obstructed plume considerations. 

38 

39 The classification of electrical enclosures and the determination of their corresponding HRR 

40 probability distributions is currently available in Appendix G of NUREG/CR-6850 (EPRI 

41 1011989). These distributions are applied to a given electrical enclosure based on three 

42 factors: qualified versus unqualified cable, open versus closed doors, and single versus multiple 

43 cable bundles. As suggested earlier, the methods and data documented in this report provide 

44 more refined electrical enclosure classifications and corresponding peak HRR distributions. 

45 
xvi 

1 The new electrical enclosure classifications are based on their electrical function, size, and 

2 content. Most power enclosures such as switchgear, load centers, motor control centers, 

3 battery chargers and power inverters are grouped based on function. Other applicable electrical 

4 enclosures are classified as small, medium, or large based on their volumetric size. The 

5 classification is primarily based on the size because it can easily be assessed by visual 

6 inspection during walkdowns without the need for opening the electrical enclosure. “Large” and 

7 “medium” volumetric classifications can be refined to account for the amount of combustible fuel 

8 load, type of cable insulation material, and ventilation configuration. These refinements can 

9 result in lower HRR values based on visual inspection of the enclosure internals. 

10 

11 In practice, the classification described above is intended to work as follows. Electrical 

12 enclosures are first classified based on function and size. This classification should be a quick 

13 determination since it only requires external visual inspection and knowledge of the enclosure 

14 function. A “default” peak HRR distribution is assigned to this initial classification. This default 

15 distribution is intended to be conservative as no visual inspection of the enclosure internals is 

16 necessary. Based on visual inspection of the enclosure internals, the initial classification can be 

17 refined with one of two sub-groups: “low” and “very low” loading. These low and very low 

18 categories would allow analysts additional flexibility to reflect actual plant conditions identified 

19 through plant walkdowns and the examination of enclosure internals. 

20 

21 The revised peak HRR probability distributions (i.e., gamma distributions) for each of the new 

22 enclosure classification groups were developed based on the following factors: 

23 

24  Review of experimental factors and configurations in testing programs intended to 

25 assess the HRR generated by electrical enclosure fires. Both domestic and international 

26 test programs were included within the scope of this research. 

27  Statistical analysis of the applicable experimental results. 

28  Extensive review and comparison of existing electrical enclosure configurations and 

29 operating experience in commercial NPPs and the influencing experimental factors. 

30 

31 Consistent with Appendices E and G of NUREG/CR-6850 (EPRI 1011989), the probability 

distributions are defined based on the 75th and 98th percentile values, with the 98th 32 percentile 

33 value intended for use as the maximum (or peak) HRR to be assumed for any enclosure in a 

given type/function classification group. The 98th 34 percentile value is also the value used during 

35 initial ignition source screening. 

36 

37 In order to provide a comprehensive characterization of electrical enclosure fires, the working 

38 group evaluated the temperature characteristics of fire plumes associated with these events 

39 using the National Institute of Standards and Technology’s (NIST) Fire Dynamics Simulator 

40 (FDS), version 6.0.1. In practice, fire plume temperatures are used to define the vertical 

41 component of a zone of influence (ZOI). The vertical component of the ZOI is the region above 

42 the fire where the fire plume temperatures could damage electrical cables and/or cause damage 

43 to nearby secondary combustibles. 

44 

45 Current practice for determining the vertical component of the ZOI includes a relatively simple 

46 process for establishing the elevation and diameter of the fire source. Typical fire modeling also 

47 uses the closed-form correlations to predict plume temperatures given a fire located within the 

48 enclosure. This practice is conservative because the fire source is positioned assuming that the 

49 enclosure does not exist. That is, the fire plume is modeled as if the fire were out in an open 

50 location, not inside an enclosure. In reality, the enclosure itself, and especially the enclosure’s 
xvii 

1 top cover, disrupts the plume development as compared to open unobstructed plumes. A more 

2 realistic treatment of the fire plume calculation is provided to account for the dispersion of the 

3 plume as it interacts with the top plate of a steel enclosure. The resulting approach is intended 

4 to be used in plume temperature calculations supporting the characterization of the ZOI in the 

5 early stages of the fire (i.e., before significant room temperature increases). Finally, a method 

6 to account for obstructions when estimating fire plume temperatures and the vertical component 

7 of the ZOI is provided. 

8 

9 In summary, this report provides a refined approach for the characterization and modeling of 

10 fires in electrical enclosures. The report is based on recent research on electrical enclosure 

11 fires, lessons learned over the last ten years developing fire PRAs and the understanding of the 

12 corresponding risk insights, as well as new research associated with obstructed fire plumes. 

13 Examples, consolidating the information in this report, are also provided. The examples have 

14 been selected and designed to illustrate how to incorporate the research documented in this 

15 report into the existing approaches for modeling fires in electrical enclosures. 

16 

xix 

1 EPRI PERSPECTIVE 

2 

3 Since its publication in 2005, NUREG/CR-6850 (EPRI 1011989) has been extensively used as 

4 the methodology for developing fire probabilistic risk assessments (fire PRA) in support of NFPA 

5 805 and other risk-informed applications. Initial applications of the methodology resulted in 

6 conservative estimates of risk, which generated the need for methodology revisions and 

7 refinements over the past decade. Although a number of these revisions and refinements have 

8 been finalized and implemented, several technical areas have been identified where 

9 supplementary research could better characterize the fire risks at nuclear power plants. One of 

10 the most important technical areas is the characterization of the fire hazard associated with 

11 electrical cabinets. In practice, this hazard is characterized in the form of heat release rates and 

12 the corresponding temperature profile surrounding the cabinet. In order to address this need, a 

13 working group between EPRI and NRC-RES was assembled to develop new heat release rates 

14 with consideration of new test data, operating experience, and general usage of methodology. 

15 This report documents the results of the research conducted by the working group in the form of 

16 a practical methodology. Specifically, the report provides updated technical methods and data 

17 in three areas: 

18 

19  The classification of electrical cabinets in terms of function (e.g., power and control 

20 cabinets), contents, and size, 

21  The determination of peak heat release rate probability distributions for the 

22 corresponding electrical cabinets, and 

23  The development and implementation of an approach to account for obstructions when 

24 estimating fire plume temperatures generated by fires burning inside cabinets. 

25 

26 The original peak heat release rate values provided for use in fire PRAs are documented in 

27 NUREG/CR-6850 (EPRI 1011989) Table G-1. The five distributions are distinguished by cable 

28 qualification type, such that two or three distributions are expected to represent the peak fire 

29 intensity for all electrical cabinet fires at a particular plant. With the understanding that electrical 

30 cabinets at nuclear power plants are of many different sizes, shapes, functions, and 

31 configurations, the working group re-classified the electrical cabinets to more accurately 

32 represent the population in commercial nuclear power plants. These new classifications serve 

33 as the foundation to re-evaluate the peak heat release rate probability distributions. 

34 

35 The peak heat release rate probability distributions provided in this report have been developed 

36 through a consensus process, based on the results of several experimental test programs and a 

37 review of fire event experience. These peak heat release rate probability distributions can be 

38 assigned considering the cabinet function, size, and combustible content. 

39 

40 Existing practice models electrical cabinet fires assuming the fire is burning outside of the 

41 enclosure. In reality, the cabinet top cover disrupts the plume development as compared to 

42 fires occurring in the open. In order to understand the effects of obstructions in the temperature 

43 profile of fire plumes, Fire Dynamics Simulator was used to model fires inside electrical 

44 cabinets. Simulations were performed in which flames and fire plume flows were subjected to 

45 obstructions. The studies of the obstructed plume simulations demonstrate lower temperatures 

46 above the fire location compared to the unobstructed cases due primarily to the entrainment of 
xx 

1 fresh air above the obstructions. Based on this research, a new method is available for 

2 estimating temperatures associated with obstructed fire plumes. 

3 

4 With the combination of the new heat release rates and obstructed plume methodology, a more 

5 realistic representation of the fire hazard associated with electrical cabinets can be achieved. 

6 

7 

8 
xxi 

1 PREFACE 

2 

3 This report supplements previous work on heat release rates (HRRs) and fire modeling related 

4 to the fire probabilistic risk assessment (PRA) methodology and data published in NUREG/CR5 6850 (EPRI 1011989), EPRI/NRC-RES Fire PRA Methodology for Nuclear Power Facilities, 

6 Volumes 1 and 2, September 2005; and its Supplement 1 (EPRI 1019259), Fire Probabilistic 

7 Risk Assessment Methods Enhancements, September 2010. 

8 

9 In 2002, EPRI published Fire Modeling Guide for Nuclear Power Plant Applications (EPRI 

10 1002981). In June 2014, EPRI published 3002000830, Fire-Induced Vulnerability Evaluation 

11 (FIVE) Revision 2, providing an updated library of fire modeling tools to predict consequences 

12 for typical hazards found in nuclear power plants. In December 2004, NRC published NUREG1805, Fire Dynamics Tools (FDTs 13 ) – Quantitative Fire Hazard Analysis Methods for the U.S. 

14 Nuclear Regulatory Commission Fire Protection Inspection Program. In July 2013, NRC 

15 published a supplement to NUREG-1805 that expanded and updated the calculation methods 

16 included in the original NUREG. 

17 

18 In May 2007, NRC and EPRI published NUREG-1824 (EPRI 1011999), Verification and 

19 Validation of Selected Fire Models for Nuclear Power Plant Applications, consisting of seven 

20 volumes on five different fire modeling tools. These reports performed a verification and 

21 validation exercise on fire modeling analysis tools for use in fire PRAs. Subsequently, NRC and 

22 EPRI published draft Supplement 1 (EPRI 3002002182) to NUREG-1824 in November 2014 for 

23 public comment. This supplement evaluates the latest versions of the models and expanded 

24 the range of validation for the models. 

25 

26 In November 2008, NRC published NUREG/CR-6978, A Phenomena Identification and Ranking 

27 Table (PIRT) Exercise for Nuclear Power Plant Fire Modeling Applications. Through the use of 

28 nuclear power plant (NPP) specific examples, the PIRT panel identified the state of knowledge 

29 and importance of key fire phenomena necessary for successful application of fire modeling to 

30 NPP scenarios. 

31 

32 In November 2012, NRC and EPRI published NUREG-1934 (EPRI 1023259), Nuclear Power 

33 Plant Fire Modeling Analysis Guidelines (NPP FIRE MAG). This report provides fire modeling 

34 analysis guidelines for use in fire PRAs. 

35 

36 In an effort to facilitate use of fire modeling for NPP applications and improve understanding of 

37 the fire hazards associated with electrical cables, NRC has sponsored two major research 

38 programs. The first program examined the impact of fire on cable functionality. The results of 

39 this research were documented in the three volumes of NUREG/CR-6931, Cable Response to 

40 Live Fire (CAROLFIRE), published in 2007. The second test program examined the 

41 flammability properties of cables and is documented in the NUREG/CR-7010 reports. Volume 1 

42 of the NUREG/CR-7010 series, Cable Heat Release, Ignition, and Spreading Tray Installations 

43 during Fire (CHRISTIFIRE) was published in 2012 and examined cables in horizontal trays. 

44 Volume 2 was published in 2013 and provided results for cables in vertical trays and corridors. 

45 Experiments are currently underway and a third volume will explore the conditions necessary to 

46 achieve ignition of cables and effectiveness of protective measures (i.e., coatings) for cables. 

47 
xxii 

1 In December 2014, NRC and EPRI published NUREG-2169 (EPRI 3002002936), Nuclear 

2 Power Plant Fire Ignition Frequencies and Non-Suppression Probability Estimation Using the 

3 Updated Fire Events Database. This report provides fire ignition frequencies and non4 suppression probability estimates through the year 2009 using EPRI’s updated fire events 

5 database (EPRI 1025284). 

6 

7 This document does not constitute regulatory requirements. NRC-RES participation in 

8 this study does not constitute or imply regulatory approval of its applications based 

9 upon this methodology.

10 
xxiii 

CITATIONS 

This report was prepared by the following: 

U.S. Nuclear Regulatory Commission 

Washington, D.C. 20555-0001 

Principal Investigators: 

N. Melly 

D. Stroup 

G. Taylor 

Under contract to NRC: 

Brookhaven National Laboratory 

P.O. Box 5000 

Upton, NY 11973 

Principal Investigator: 

M. Subudhi 

Consultant 

101 Clancy Drive, NE 

Albuquerque, NM 87112 

Principal Investigator: 

S. Nowlen 

Utility participant/preparer: 

Duke Energy 

410 South Wilmington St., NCRH 19 

Raleigh, NC 27602 

Principal Investigator: 

J. DeJoseph 

Electric Power Research Institute 

3420 Hillview Avenue 

Palo Alto, CA 94304 

Principal Investigator: 

A. Lindeman 

Under contract to EPRI: 

Jensen Hughes, Inc. 

3610 Commerce Dr. Suite 817 

Baltimore, MD 21227 

Principal Investigators: 

F. Joglar 

V. Ontiveros 

J. Williamson 

Engineering Planning and Management 

5520 Dillard Drive, Suite 250 

Cary, NC 27518 

Principal Investigator: 

D. Miskiewicz 

This report describes research sponsored jointly by the U.S. Nuclear Regulatory Commission’s 

(NRC) Office of Nuclear Regulatory Research (RES) and the Electric Power Research Institute 

(EPRI). 

The report is a corporate document that should be cited in the literature in the following manner: 

Refining And Characterizing Heat Release Rates From Electrical Enclosures During Fire 

(RACHELLE-FIRE), Volume 1: Peak Heat Release Rates and Effect of Obstructed Plume, U.S. 

Nuclear Regulatory Commission, Office of Nuclear Regulatory Research (RES), Rockville, MD, 

and Electric Power Research Institute (EPRI), Palo Alto, CA: 2015. NUREG-2178, V1, and 

EPRI 3002005578. 

xxv 

1 ACKNOWLEDGMENTS 

2 

3 This report was completed using a working group, which included stakeholders from the U.S. 

4 Nuclear Regulatory Commission (NRC) and the Electric Power Research Institute (EPRI). The 

5 authors appreciate the support of their respective organizations that cooperatively shared some 

6 or all of the cost and time for participation in this study. 

7 

8 The working group members would like to thank Dr. Manomohan Subudhi, Brookhaven National 

9 Laboratory (BNL), for facilitating the working group discussions and developing the early drafts 

10 of this report. 

11 

12 Special thanks go to Dr. Justin Williamson and Dr. Victor Ontiveros of Jensen Hughes, under 

13 the guidance of Dr. Francisco Joglar, for running the National Institute of Standards and 

14 Technology (NIST) Fire Dynamics Simulator models for the obstructed plume characterization. 

15 The authors thank Dr. Kevin McGrattan of NIST for his presentation and discussions of the 

16 results from the NRC-sponsored electrical enclosure tests conducted by NIST at the Naval 

17 Research Laboratory’s Chesapeake Bay Fire Test Detachment facility. The authors are grateful 

18 to Mr. Mark Schairer of EPM for his peer review of the obstructed plume study. Special thanks 

19 go to working group member Ms. Joelle DeJoseph and Duke Energy for providing a large library 

20 of electrical enclosure pictures as well as piloting the new heat release rates and obstructed 

21 plume methodology. 

22 

23 The technical support of Mr. Kenneth Hamburger and Mr. Philip Smith of NRC, who participated 

24 in working group meetings, provided analysis of fire test data, and supplied input to the fire size 

25 calibration exercises, is acknowledged and greatly appreciated. Timely publication of this 

26 document would not have been possible without assistance from the NRC’s Office of 

27 Administration. Specifically, the authors thank Tojuana Fortune-Grasty for her efforts in 

28 publishing this report. Finally, the authors express appreciation for the editorial support 

29 provided by the EPRI staff. 

30 

31 

xxvii 

1 ACRONYMS 

2 

3 AC Alternating Current 

4 ACRS Advisory Committee on Reactor Safety 

5 ADAMS Agencywide Documents Access and Management System 

6 ARCH_xxx Obstruction Case with Flat Plate and Two Side Walls 

7 BASE_xxx Base Case with No Obstruction 

8 BNL Brookhaven National Laboratory 

9 Btu British thermal unit 

10 CBD Chesapeake Bay Fire Test Detachment 

11 CCDP Conditional Core Damage Probability 

12 CD Compact Disc 

13 CDF Core Damage Frequency 

14 CFD Computational Fluid Dynamics 

15 CFR Code of Federal Regulations 

16 COR Code of Record 

17 DC Direct Current 

18 DUKE Duke Energy 

19 EPM Engineering Planning and Management 

20 EPRI Electric Power Research Institute 

21 FAQ Frequently Asked Questions 

22 FDS Fire Dynamics Simulator 

23 FEDB Fire Events Data Base 

24 FMC Flexible Metal Conduit 

25 FR Federal Register 

26 HAI Hughes Associates and RJA Group 

27 HEAF High Energy Arcing Fault 

28 HELEN-FIRE Heat Release Rates of Electrical Enclosure Fires 

29 HGL Hot Gas Layer 

30 HRR Heat Release Rate 

31 IEEE Institute of Electrical and Electronics Engineers 

32 IRSN Institute de Radioprotection et de Surete Nucleaire (France) 

33 kW kilowatt 

34 LFMC Liquid-Tight Flexible Metal Conduit 

35 MCB Main Control Board 

36 MCC Motor Control Center 

37 MW Megawatt 

38 NEI Nuclear Energy Institute 

39 NFPA National Fire Protection Association 

40 NIST National Institute of Standards and Technology 

41 NPP Nuclear Power Plant 

42 NRC Nuclear Regulatory Commission 

43 NSP Non-Suppression Probability 

44 OBST_xxx Obstruction Case with Flat Plate 

45 PAU Plant Analysis Unit 

46 PMMA Poly(methyl methacrylate) 

47 PRA Probabilistic Risk Assessment 
xxviii 

1 RACHELLE-FIRE Refining And Characterizing Heat Release Rates From Electrical 

2 Enclosures During Fire 

3 RES NRC’s Office of Nuclear Regulatory Research 

4 RI/PB Risk-Informed/Performance-Based 

5 SDP Significance Determination Process 

6 SF Severity Factor 

7 SIS Switchboard Wire or XLPE-Insulated Conductor (see UL 44, TS-Insulated 

8 Wires and Cables) 

9 SNL Sandia National Laboratory 

10 SR Silicon Rubber 

11 STD Standard 

12 TP Thermoplastic 

13 THREEWALL_xxx Obstruction Case with Flat Plate and Three Side Walls 

14 TS Thermoset 

15 UL Underwriter Laboratory 

16 US United States 

17 VAC Voltage in AC 

18 V&V Verification and Validation 

19 VTT Valtion teknillinen tutkimuskeskus (Finland) 

20 WG Working Group 

21 XLPE Cross-Linked Polyethylene 

22 ZOI Zone of Influence 

23 

24 

25 
1-1 

1 1

2 Introduction 

3 1.1 Background 

4 In 2001, the National Fire Protection Association (NFPA) issued the first edition of NFPA 805, 

5 Performance-Based Standard for Fire Protection for Light-Water Reactor Electrical Generating 

Plants, 2001 Edition [1]1 6 . On July 16, 2004, the U.S. Nuclear Regulatory Commission (NRC) 

7 amended its regulations in Title 10, Section 50.48, of the Code of Federal Regulations (10 CFR 

8 50.48), Fire Protection [2], to allow U.S. utilities to adopt and maintain risk-informed, 

9 performance-based fire protection programs. Paragraph (c) of 10 CFR 50.48 endorses, with 

10 exceptions, the NFPA 805 Standard – 2001 Edition, as a voluntary alternative for demonstrating 

11 compliance with the deterministic programs given in Appendix R to 10 CFR 50 [3] in accordance 

12 with Paragraph (b) of 10 CFR 50.48 or the plant-specific fire protection license conditions. 

13 

14 In 2005, the Electric Power Research Institute (EPRI) and the NRC’s Office of Nuclear 

15 Regulatory Research (RES) issued a joint technical report titled EPRI/NRC-RES Fire PRA 

Methodology for Nuclear Power Facilities, EPRI 1011989, NUREG/CR-6850 [4]2 16 , presenting 

17 methods and data for conducting a fire probabilistic risk assessment (fire PRA). As utilities 

18 develop fire PRAs to support a transition to NFPA 805 or in pursuit of other risk-informed 

19 applications, the methods in NUREG/CR-6850 have been used extensively. The methodology 

20 described in NUREG/CR-6850 for modeling fires in electrical enclosures generally consisted of: 

21 

22 1. Identifying the electrical enclosures that should be considered ignition sources in a fire 

23 PRA (see Chapter 6 of NUREG/CR-6850 and associated fire PRA frequently asked 

24 questions (FAQs)), 

25 2. Assigning a heat release rate probability distribution to the peak heat release rate (see 

26 Appendices E and G of NUREG/CR-6850), and 

27 3. Determining the region nearby the electrical enclosure where the fire could generate 

28 damage to nearby equipment and cables. This region is usually referred to as the zone 

29 of influence (ZOI) (see Chapter 8 and Appendix F of NUREG/CR-6850). 

30 

31 Although the first and third items were not new concepts introduced by NUREG/CR-6850 (i.e., 

32 previous fire PRA methodologies provided similar or identical information), the second item was 

33 new. Earlier fire PRA methods provided the characterization of electrical enclosures using point 

34 values for the heat release rate instead of probability distributions. The reason why 

35 NUREG/CR-6850 provided the use of probability distributions was twofold. First, this approach 

36 allows for the uncertainty associated with the heat release rates (HRRs) to be considered in the 

37 risk quantification process. Second, it allows for an independent assessment of the severity 

38 factor term in the risk equation based on the characteristics of the electrical enclosure (i.e., the 

39 ignition source) and the geometry/configuration of the fire scenario that could be generated by 

40 the postulated fire. 

 

1

 Ref. 1, NFPA 805, 2001 Edition is hereafter referred to as “NFPA 805”, and all references to this 

standard refer to the 2001 edition of this standard, which is the code of record (COR) as required by NRC 

regulations. 

2

 Ref. 4, NUREG/CR-6850 (EPRI 1011989) is hereafter referred to as “NUREG/CR-6850”. 
INTRODUCTION 

1-2 

1 

2 Fire modeling is used to support fire PRAs to determine the effects of fire hazards on plant 

3 cables and equipment. For most fire model applications, the HRR of the fire is the most 

important parameter to specify. The HRR, measured in kilowatts (kW)3 4 , is the rate at which the 

5 combustion reaction produces heat. Appendix G of NUREG/CR-6850 provides peak HRR 

6 distributions for fixed ignition sources, such as electrical enclosures. For electrical enclosures, 

7 five heat release distributions are specified, which are dependent on 1) the number of cable 

8 bundles, 2) the type of internal combustibles (e.g., cable insulation material), and 3) the 

9 ventilation conditions (open/closed doors). 

10 

11 The wide application of the methods and data summarized above over the last ten years, 

12 together with fire research conducted after NUREG/CR-6850 was published, has led to the 

13 identification of key areas in the fire modeling of electrical enclosures where refinements can be 

14 developed. Specifically: 

15 

16  A number of testing programs for evaluating heat release rates in electrical enclosures 

17 have recently been completed. For example, in 2013 a series of experiments were 

18 sponsored by NRC-RES and conducted by the National Institute of Standards and 

19 Technology (NIST) at the Chesapeake Bay Fire Test Detachment (CBD) of the Naval 

20 Research Laboratory to obtain additional data to support re-quantification of HRR 

21 estimates for electrical enclosures. This testing effort used electrical enclosures 

22 removed from a nuclear facility, and electrical cables and panel wiring representative of 

23 those commonly found in U.S. nuclear power plants. In total, 112 individual fire tests 

24 were conducted, and the result of this effort is documented in a draft report, “Heat 

25 Release Rates of Electrical Enclosure Fires (HELEN-FIRE)” [7]. 

26 

27  An extensive collection and review of recent fire events records throughout the entire 

28 U.S. nuclear industry was conducted. 

29 

30  Numerous fire PRAs have been developed providing specific information (e.g., 

31 numerous pictures of cabinet internals, detailed enclosure construction specifications, 

32 etc.) associated with potential influencing factors in electrical enclosure fires. 

33 

34 Refinements are necessary because a comparison of the fire modeling results and resulting risk 

35 contribution of electrical enclosure fires compared with the fire experience in the U.S. 

36 commercial nuclear industry suggests that current information may be conservative for fire 

37 scenarios presenting specific characteristics. 

38 1.2 Approach 

39 The characterization of fires inside electrical enclosures has been identified as a technical area 

40 where existing methods and data could be refined. In an effort to obtain more realistic data for 

41 analysis of electrical enclosure fires and associated peak heat release rates, the Nuclear 

42 Regulatory Commission’s Office of Nuclear Regulatory Research sponsored a program with the 

43 National Institute of Standards and Technology. Subsequent to the completion of that test 

44 program, RES together with the Electric Power Research Institute established a working group 

45 composed of technical experts in experimental test programs, fire PRA, operating experience, 

46 fire modeling, and circuit analysis to review the new data, other available test data, and industry 

47 experience in an effort to develop refinements in the information. 

 

3

 1 Btu/s is equal to 1.055 kW. 
INTRODUCTION 

1-3 

1 

2 During the project planning phase, the project sponsors evaluated the potential approaches to 

3 achieve the specific objectives of this report. Options included the use of formal expert 

4 elicitation panels, methods development panels, and facilitated working groups. It was decided 

5 not to pursue a formal expert elicitation type process due to the availability of test data, 

6 operating experience, an established and acceptable methodology for implementation, and the 

7 understanding of influencing factors affecting the diffusion flame combustion process. The 

8 methods development panel approach was not explored because the overall method presented 

9 in NUREG/CR-6850 is considered to be reasonable and development of a different method was 

10 determined to be unnecessary. Instead, the use of a facilitated working group (WG) 

11 represented by members with the collective professional experience to reach a consensus in 

12 estimating the peak HRR distributions for electrical enclosures in typical NPP configurations and 

13 to address some of the challenging fire modeling issues was chosen. The decision to use the 

14 facilitated WG approach was based on the nature of the planned work, the urgency of the 

15 needed information to support fire PRA application reviews, increased efficiency (provided a 

16 consensus opinion could be reached quickly), and the availability of test data to support the 

17 planned efforts. Where expertise beyond the collective knowledge of the WG was needed, 

18 individual experts were consulted. At this time, consultation with non-WG experts was primarily 

19 in the fire modeling area although experts were also asked to comment on the proposed 

20 enclosure classification groups. 

21 

22 The WG representation was balanced between the regulator (i.e., four members from the 

23 NRC/National Laboratories) and the nuclear power industry (i.e., four members from 

24 EPRI/nuclear power industry). The WG members are listed below, along with their affiliations. 

25 Brief resumes are included in Appendix A. 

26 

27 Joelle DeJoseph, Duke Energy (DUKE) 

28 Francisco Joglar, Jensen Hughes (HAI) 

29 Ashley Lindeman, Electric Power Research Institute (EPRI) 

30 Nicholas Melly, U.S. Nuclear Regulatory Commission (NRC-RES) 

31 David Miskiewicz, Engineering Planning and Management (EPM) 

Steven Nowlen, Consultant4 32 

33 David Stroup, U.S. Nuclear Regulatory Commission (NRC-RES) 

34 Gabriel Taylor, U.S. Nuclear Regulatory Commission (NRC-RES) 

35 

36 A number of additional subject matter experts also participated in WG meetings. Mr. Mark 

37 Henry Salley of NRC-RES provided general assistance and oversight. Dr. Kevin McGrattan of 

38 NIST provided technical assistance associated with the Fire Dynamics Simulator (FDS) 

39 software and fire test results conducted at the CBD facility. Dr. Justin Williamson and Dr. Victor 

40 Ontiveros of Jensen Hughes performed the computer simulations of obstructed plumes. Finally, 

41 Dr. Manomohan Subudhi of Brookhaven National Laboratories (BNL) served as the 

42 moderator/facilitator of the meetings and discussions. 

43 

44 In developing the information documented in this report, the facilitated WG held four multi-day 

45 meetings between April and September 2014. A summary of the working group’s interactions is 

46 included in Appendix B. These meetings allowed the WG to effectively communicate opinions 

47 and receive constructive feedback on possible approaches for addressing the project objectives. 

48 The early meetings allowed the WG to formulate a project outline and actions to be completed, 

 

4

 Steven Nowlen (retired) was a Distinguished Member of the Technical Staff at Sandia National 

Laboratories. 
INTRODUCTION 

1-4 

1 while the later meetings allowed the WG’s progress to be reviewed and formalized. In the latter 

2 half of this process, weekly conference calls were also held to update WG members on the 

3 status of current and planned activities. Ultimately, the results and approaches presented in this 

4 report represent the WG’s consensus opinion. 

5 1.3 Scope and Terminology 

6 The RACHELLE-FIRE program deals with the analysis of fires that originate in electrical or 

7 electronic equipment housed within a support structure, generally metal, that is either enclosed 

8 or made up of open rack-type panels or supports. In this report, these housings are referred to 

9 as “electrical enclosures.” The term “electrical enclosure” is meant to be broadly inclusive of 

10 essentially any box or structure, with the exception of cable trays and conduits, whose primary 

11 purpose is to house electrical and/or electronic components. “Electrical enclosure” as used in 

12 this report does encompass the open rack panels used in some NPP applications even though, 

13 strictly speaking, these are not enclosures (e.g., a relay rack or an open support structure used 

14 to house instrument and/or control components).

15 

16 In past practice, a variety of terms have been used to identify these same items. For example, 

17 NUREG/CR-6850 used the terms “panel” and “cabinet” extensively. The terms “relay rack,” 

18 “control or circuit boards,” and “junction box” are also used. In general, “electrical enclosure” is 

19 a more widely recognized and generic term used among electrical equipment manufacturers 

20 and electrical engineers (e.g., see the various standards published by the National Electrical 

21 Manufacturers Association). The term “electrical enclosure” as used in this report is inclusive of 

22 cabinets, panels, and relay racks as those terms are used in NUREG/CR-6850 and other 

23 related fire PRA documents and standards. 

24 

25 In NUREG/CR-6850 the term “enclosure” is used in two other contexts—namely, the regulatory 

26 issue of cables and components that share a “common enclosure” (e.g., cables routed in the 

27 same cable tray), and the modeling of “enclosure fires” (i.e., fires that occur within a room as 

28 opposed to fires that occur in an open unconfined space). The reader is cautioned not to 

29 confuse these unrelated uses of the word “enclosure.” 

30 

31 The facilitated WG developed fire source burning behaviors characterized by a distribution on 

32 peak HRR reflecting the aleatory uncertainty associated with fire development. The WG used 

33 the same approach that was used when developing the distributions found in Appendix G of 

34 NUREG/CR-6850 and did not attempt to explicitly characterize the uncertainty of these peak 

35 HRR distributions or the appropriateness of using a two-parameter distribution profile whose 

parameters were derived from the 75th and 98th 36 percentile WG consensus estimates. 

37 

38 The fundamental scope of this report is the characterization and analysis of those plant fire 

39 ignition sources that, under NUREG/CR-6850 - Task 6, have been counted as members of fire 

40 ignition source: Bin 4 - main control board, Bin 10 - battery chargers, and Bin 15 - electrical 

41 cabinets. The methods of this report are not applicable to any other fire ignition source and, in 

42 particular, are not applicable to electrical enclosures that are either not counted as fire ignition 

43 sources (per the counting information) or that are counted as junction boxes (fire ignition source 

44 Bin 18). This report also does not deal with high energy arcing fault initiated fires in any 

45 electrical enclosure (fire ignition source Bin 16). 

46 

47 NUREG/CR-6850 also refers to "qualified thermoplastic cables” when setting the fire 

48 characteristics of electrical enclosure fires. In this context, the designation “qualified” is a 

49 reference to the IEEE-383 cable qualification standard which originally included a vertical flame 
INTRODUCTION 

1-5 

spread test5 1 . The IEEE-383 flame spread test has been a common historical flammability 

2 benchmark used in the U.S. nuclear power industry, and cables that pass that test are 

3 considered “qualified” as low flame spread. Since publication of the IEEE-383 standard in 1975 

4 it has been common practice for plants to specify low flame spread cables per that test in 

5 procurement actions. In some cases cables have also been “back-qualified” through testing 

6 done some time after procurement and/or installation. Note that the flame spread test is only a 

7 minor aspect of the overall IEEE-383 standard which focuses mainly on severe accident 

8 equipment qualification testing. Cables that pass the flame spread test may not comply with 

9 other portions of the standard but would still be considered low flammability. 

10 

11 The intended practice under the methods presented here is to treat qualified TP cables (i.e., 

12 cables shown to pass the IEEE-383 flame spread test) consistently with the treatment outlined 

13 in NUREG/CR-6850; namely, qualified TP cables are given equivalent status relative to fire 

14 characterization as are TS cables. That is, if the application involves TP cables but those 

15 cables were tested and passed the IEEE-383 flame spread test, then the analyst may treat 

16 those cables as equivalent to TS cables when selecting the appropriate peak HRR distribution 

17 (e.g., when applying Tables 4-1 and 4-2 from this report). 

18 1.4 Objectives 

19 This report documents the working group’s efforts and consensus in three technical areas: 

20 

21 1. The classification of electrical enclosures typically selected as ignition sources in 

22 probabilistic studies (i.e., fire modeling or fire PRAs) in the commercial nuclear power 

23 industry, 

24 2. The characterization of peak HRRs associated with the different electrical enclosures, 

25 and 

26 3. The characterization of fire plume temperatures generated by fires inside electrical 

27 enclosures. 

28 

29 The research results in these three areas were consolidated in the form of technical information 

30 that can be applied in fire modeling studies supporting fire PRAs. This technical information 

31 includes: 

32 

33 1. The classification of electrical enclosures in terms of function, size, contents, and 

34 ventilation conditions, 

35 2. The determination of peak HRR probability distributions considering specific electrical 

36 enclosure characteristics such as function, size, ventilation conditions, and combustible 

37 content, and 

38 3. The characterization of fire plumes associated with fires in electrical enclosures. 

39 

40 It should be noted that the methods and data described in this report are a supplement to 

41 existing methods and data, primarily documented in NUREG/CR-6850, its corresponding 

42 supplement, and fire PRA FAQs. Analyses already completed with the existing methods and 

43 data can be considered bounding and may not need to be supplemented with the information 

44 provided in this document. Specifically: 

45 

 

5

 Note that since its original publication under IEEE-383, the flame spread test portion of the standard has 

been removed from IEEE-383 and published instead under IEEE-1202. The two tests are the same. 
INTRODUCTION 

1-6 

1  The classification of electrical enclosures is consistent and does not affect the existing 

2 ignition source counting information available in Chapter 6 of NUREG/CR-6850 and 

3 applicable fire PRA FAQs. 

4  The probability distributions for peak HRRs can replace the ones currently available in 

5 Appendix E and G of NUREG/CR-6850. However, the existing distributions in 

6 NUREG/CR-6850 are considered bounding when compared with their corresponding 

7 counterparts described in this document. 

8 

9 The characterization of fire plumes generated by fires in electrical enclosures, when applicable 

10 to a given scenario, is expected to produce lower plume temperatures than the ones obtained 

11 using existing information. Consequently, the existing information is bounding, as the use of 

12 “unobstructed” fire plume temperature models produces higher gas temperatures. 

13 

14 The revised peak heat release rate distributions and the obstructed plume study may affect the 

15 size of the fire zone of influence (ZOI). The ZOI is a crucial element of the fire PRA 

16 development as it has a direct impact on damaged equipment postulated in the fire PRA 

17 response model. 

18 1.5 Report Organization 

19 This report is organized as follows: 

20 

21  Chapter 2 describes the activities and process used by the working group to develop the 

22 new heat release rate distributions and the obstructed plume methodology. 

23 

24  Chapters 3 and 4 discuss the classification of electrical enclosures. Chapter 3 describes 

25 the new electrical enclosure classification groups. This chapter also describes the effect 

26 of the enclosure internal fuel load configuration on the peak HRR. Chapter 4 documents 

27 the consensus peak HRR probability distributions for the different electrical enclosure 

28 classification groups. 

29 

30  Chapters 5 and 6 describe the research associated with obstructed fire plume 

31 temperatures. Specifically, Chapter 5 describes the technical basis for the methodology 

32 provided in this report. The methodology and example applications are provided in 

33 Chapter 6. 

34 

35  Chapter 7 provides the summary of results and conclusions of this study. In addition, 

36 areas for future research as discussed during the working group meetings are identified 

37 in this chapter. 

38 

39  Appendix A includes the resumes of WG members, technical contributors, and working 

40 group moderator. 

41 

42  Appendix B provides an overview of the deliberation activities of the WG members on 

43 estimating the HRR distributions for various enclosure types. This includes the process 

44 used by the WG, and defined issues that were considered by the WG in this project. 

45 

46  Appendix C presents a library of pictures and descriptions for the electrical enclosure 

47 types described in Chapter 3. These pictures serve as information for the classification 

48 of electrical enclosures in specific applications. 
INTRODUCTION 

1-7 

1 

2  Appendix D summarizes the statistical analysis in support of the peak HRR probability 

3 distributions described in Chapter 4. The statistical analysis is based on available fire 

4 test results for the different enclosure classifications. 

5 

6  Appendix E lists the obstructed plume temperature numerical results obtained using 

7 FDS. 

8 

9  Appendix F describes several examples illustrating the application of the revised peak 

10 HRR probability distributions and the implementation of the information associated with 

11 obstructed fire plume temperatures for determining the vertical component of the ZOI. 

12 

13  Appendix G is a compact disc (CD) containing the fire modeling software, input files, and 

14 other information used to develop the results in this report. 

15 

2-1 

1 2

2 Overview of the Process 

3 This chapter describes activities by the working group (WG) members and the process followed 

4 to: (1) classify electrical enclosures, (2) develop revised heat release rate (HRR) distributions for 

5 each classification, and (3) investigate the fire plume characterization generated by electrical 

6 enclosure fires. The following sections describe each of these topics in detail. Although the 

7 process for each of these three activities is described separately, there was overlap, especially 

8 between the electrical enclosure classification and the development of the updated peak HRR 

9 values. 

10 2.1 Classification of Electrical Enclosures 

11 The classification of electrical enclosures is based on the following process: 

12 

13  Review existing enclosure classification guidance documented in Appendix G of 

14 NUREG/CR-6850. The review supported an understanding of: 

15 o Existing guidance for classifying electrical enclosures 

16 o Application/experience using the existing approach 

17 o Limitations and areas for enhancement/realism 

18  Review the fire hazards associated with electrical enclosures, including: 

19 o Extensive review of photographs depicting electrical enclosure internals to 

20 assess variability in fuel load and configuration 

21 o Equipment functional differences 

22 o Discussion of ignition source strength/types among the different electrical 

23 enclosures 

24 o Collection and review of available experimental test series 

25 o Review of U.S. operating experience using the Updated Fire Events Database 

26 (EPRI 1025284) 

27 o Focus on implementation and practical application 

28 2.1.1 Review of Existing Guidance 

29 The WG reviewed Appendix G of NUREG/CR-6850, specifically Table G-1, which lists the 

30 recommended heat release rate (HRR) probability distributions for five different types of 

31 enclosures. The classification of all electrical enclosures into five ignition source groups is 

32 based primarily on: 

33 

34  Number of cable bundles, i.e., one cable bundle or more than one bundle 

35  Qualified or unqualified cables 

36  Open or closed electrical enclosure (for more than one bundle and unqualified cable) 

37 

38 The existing guidance uses cable bundle parameter characterization to correlate the 

39 recommended HRR values to fire test data configurations from the NRC/SNL [8] and VTT [9, 

40 10, 11] control electrical enclosure test programs. Similarly, the ventilation configuration of the 

41 enclosure (i.e., open or closed electrical enclosure) and the qualification of the cables involved 

42 in the tests also correlated to the experimental programs. 
OVERVIEW OF THE PROCESS 

2-2 

1 

2 A key limitation of the original Appendix G electrical enclosure classification approach is in its 

3 practical application. For example, the original authors have stated that their intent was that the 

4 single bundle cases would cover most of the higher voltage power switching equipment (e.g., 

5 switchgear and load centers) and most other enclosures would likely fall into the “more than one 

6 bundle” cases including those with significant fuel loads other than cables (e.g., control 

7 components). It was also intended that the “single bundle” cases would include cases where an 

8 enclosure contained more than one bundle but due to the internal configuration, fire was likely to 

9 impact only a single bundle at a time (e.g., internal separation of the bundles with no significant 

10 inter-bundle fuel available). However, unless internal inspection was possible, analysts appear 

11 to default to the higher “more than one bundle” cases and, in practice, the latter argument, fire 

12 will remain confined to one bundle, has been difficult to justify. 

13 

14 The WG also noted that based on Table G-1 of NUREG/CR-6850, PRA analysts had, in some 

15 cases, assigned unreasonably high peak HRR values to certain small and medium size 

16 enclosures. This is a result of the relatively low number of electrical enclosure peak HRR 

17 estimates available for selection. 

18 

19 The working group agreed that a classification based on size and functionality of the electrical 

20 enclosure would provide a more practical implementation of the methodology. The WG 

21 determined that these are factors that can be easily determined by visual inspection during a 

22 walkdown without the need to open the electrical enclosure. At the same time, a classification 

23 based on enclosure size and functionality generated the need for understanding the fire hazards 

24 associated with the different functions and sizes. 

25 2.1.2 Understanding the Fire Hazards Associated with Different 

26 Electrical Enclosures 

27 In order to understand the effects enclosure function, size, and combustible loading 

28 characteristics have on peak fire vulnerability, the WG reviewed hundreds of electrical enclosure 

29 photographs of closed and open door configurations currently installed in commercial nuclear 

30 power plants (NPPs). During the review process, the WG discussed in detail the typical 

31 configurations for specific types of electrical enclosures to support a common understanding 

32 among the WG members of the similarities and differences among the types of electrical 

33 enclosures found in commercial NPPs. Additionally, the WG collected and studied experimental 

34 data and operating experience associated with electrical enclosure fires. Based on these 

35 activities, the WG considered the following attributes for electrical enclosure fires in classifying 

36 all relevant ignition sources: 

37 

38  An enclosure’s internal volume and the amount of combustible materials (mostly cable 

39 insulations and electronic cards) have a significant effect on the maximum fire size if the 

40 ignition remains undetected and unsuppressed. 

41 

42  Experience has shown that voltage and current ratings can have a significant effect on 

43 the ignition size and duration of the pre-growth phase of a fire. However, there is 

44 essentially no evidence to show how these factors would impact the peak HRR. The 

45 presumption of the working group is that once ignited, higher ignition energies available 

46 would tend to increase the likelihood of larger fires, but ignition energy has very limited 

47 effect on the worst-case peak HRR values. 

48 
OVERVIEW OF THE PROCESS 

2-3 

1  Switchgear, load centers, motor control centers (MCCs), power inverters, and battery 

2 chargers are normally housed in closed, vented enclosures and have very small 

3 amounts of cables, limiting the size of the expected fires. Variations among the 

4 equipment manufacturers and from plant to plant installations are not significant enough 

5 to affect the fire characteristics among enclosures within each of these functional types. 

6 

7  Neatly organized internals (e.g., jacket-stripped cable with conductor bundles neatly 

8 zip-tied and run in an orderly fashion along the walls of the enclosure, wires leading to 

9 enclosure internals neatly arranged and run in tight bundles between the mounted 

10 electrical and electronic devices, high levels of internal partitioning with some 

11 components housed in internal metal enclosures within a larger enclosure) are more 

12 difficult to ignite and take a longer time for initial ignition and fire growth than disorderly 

13 contents (e.g., loose or no bundling of cables, large quantities or small conductor wires 

14 routed throughout, quantities of excess or spare cable often left inside an enclosure, 

15 wide dispersal of fuels over the enclosure interior). Even given well organized contents, 

16 once the conductor bundle ties melt, tests have shown that the fire size could grow 

17 rapidly, but in general, a larger initial fire is needed and a relatively lower peak HRR 

18 value will still be expected than that given an enclosure with disorderly internals. 

19 

20  Enclosure venting conditions range from fully open equipment racks to fully enclosed 

21 and tightly sealed conditions. Larger enclosures usually have some degree of venting, 

22 typically top and bottom louvers on the horizontal face of the enclosure, that provide for 

23 adequate ventilation and cooling of devices when in operation. Fire tests have shown 

24 that ventilation characteristics have a major effect on the fire growth inside an enclosure 

25 [7, 8]. A fire under an open configuration can grow to a larger size than one inside a 

26 closed enclosure, due to the ventilation effect. 

27 

28  Tests have shown that cables with thermoplastic (TP) conductor insulation ignite and 

29 spread fire far more easily than those with thermoset (TS) insulation. Tests have also 

30 shown that TP cables qualified as low flame spread per the IEEE-383 standard vertical 

31 flame spread test will show substantially reduced flammability compared to an 

32 unqualified cable. Finally, switchboard (SIS) wire, which is widely used in manufacturer 

33 pre-wired installations, is also subject to rigid flammability testing and is considered at 

34 least equivalent to TS cable in terms of flammability. 

35 

36  Fires more readily spread vertically upward inside an enclosure than horizontally across 

37 the enclosure width. Given enough time, conditions conducive to flame spread may 

38 result in the involvement of all combustibles inside an enclosure. 

39 

40 After deliberation, the WG proposed an initial set of enclosure classification groups based on 

41 enclosure type/function rather than number of cable bundles. The final classification groups 

42 evolved slightly through the rest of the process but remained largely as defined originally. 

43 Chapter 3, “Classification of Electrical Enclosures,” describes the four classification groups and 

44 associated sub-groupings in detail, along with the factors considered to support this 

45 classification. The first three groups are based on the equipment functional classification, while 

46 the last group is based on the size and is intended to represent “all other” electrical enclosures 

47 not covered by the first three classes. The classification of electrical enclosures as fire ignition 
OVERVIEW OF THE PROCESS 

2-4 

1 sources (Bins 4, 10, and 15) in accordance with Task 6 of NUREG/CR-6850 is based on 

assignment of each enclosure to one of the following classification groups1 2 : 

3 

4  Group 1: Switchgear and Load Centers 

5 

6  Group 2: MCCs and Battery Chargers 

7 

8  Group 3: Power Inverters 

9 

10  Group 4: All Other Electrical Enclosures 

11 

12 o Group 4a: Large Enclosures 

13 o Group 4b: Medium Enclosures 

14 o Group 4c: Small Enclosures 

15 2.2 Process Used in Developing the HRR Distributions 

16 The WG developed the HRR distributions, as presented in Chapter 4, for each classification 

17 group by conducting the following activities. 

18 

19  A literature survey that consisted of reviewing: 

20 o Experimental test series conducted in the U.S. and internationally over the last 

21 three decades 

22 o U.S. NPP operating experience documented in EPRI’s Fire Events Database 

23  Identification of influencing factors. The WG identified the following influencing factors: 

24 o Electrical enclosure volume 

25 o Electrical enclosure function 

26 o Combustible type 

27 o Amount of combustible materials 

28 o Combustible material configuration 

29 o Electrical ignition size/potential 

30 o Ventilation conditions 

31  Calibration exercise 

32  Assessment of electrical enclosure heat release rates 

33  Building and achieving consensus 

34  Ensuring consistency and applicability 

35  Finalizing the consensus 

36 2.2.1 Literature Review 

37 The WG began with a review of the available information relevant to electrical enclosure fire 

38 behavior, including both experimental data and actual plant fire experience. The available 

39 information included: 

40 

41  NRC/SNL control electrical enclosure fire tests [8], 

42  VTT tests from Finland [9, 10, 11], 

 

1

 Each classification group is assigned a simple alpha-numeric identifier in order to simplify aspects of the 

discussions that follow and to promote a common PRA vocabulary. It is provided that these designations 

be used as “shorthand” identifiers when citing classification results for in-plant enclosures (e.g., in fire 

PRA databases). 
OVERVIEW OF THE PROCESS 

2-5 

1  IRSN tests from France [12], 

2  recently completed set of tests by NRC/NIST [7], and 

3  the EPRI updated fire events database [13]. 

4 

5 Each test program was discussed in some detail including consideration of the test results as 

6 well as the test objectives and approach. Actual fire experience was reviewed based on the 

7 recently updated EPRI fire events database [13], which covers U.S. commercial nuclear power 

8 plant (NPP) fire events. All of the fire events involving electrical enclosures were identified and 

9 reviewed, focusing especially on plant events occurring from 1990 through 2009. Insights from 

10 the event reports were discussed and factored into the consensus process as deemed 

11 appropriate by the WG members. 

12 2.2.2 Identification of Influencing Factors 

13 The WG identified factors that can influence the HRR generated by an electrical enclosure fire. 

14 These influencing factors form the basis for determining the probability distributions for the 

15 different electrical enclosure classifications. Specifically: 

16 

17  Electrical enclosure volume: The electrical enclosure volume is a factor explicitly 

18 represented in the electrical enclosure classification for Group 4. The WG agreed that 

19 the enclosure volume provides a practical approach for classification. 

20  Combustible type: The combustible type is classified as either TP or TS cable for the 

21 final HRR distribution categories. Note that, per the discussion in Section 1.3 above, TP 

22 cables that are qualified as low flame spread per IEEE-383 flame spread test may be 

23 treated as equivalent to TS cables; that is, qualified TP cables may be mapped to the TS 

24 combustible type groups. Similar treatment is also given to SIS wire; that is, SIS wire is 

25 also mapped to the TS combustible type groups. 

26  Amount of combustible materials: The WG agreed that the amount of combustible 

27 material is similar for the types of electrical enclosures classified by their function 

28 (Groups 1-3) and for small enclosures (Group 4c). However, for the “all other” – large 

29 and medium enclosure classification groups (Groups 4a and 4b), the amount of 

30 combustible material can vary widely. For that reason, the “all other” – large and 

31 medium enclosure classifications (Groups 4a and 4b) were further divided to allow for 

32 additional resolution in assigning peak HRR probability distributions. The WG agreed 

33 that pursuit of this further refinement (low or very low combustible loading) requires 

34 internal inspection of the electrical enclosure. 

35  Combustible material configuration: Similar to the factor associated with the amount 

36 of combustible material, the WG agreed that the combustible configuration is similar for 

37 the types of electrical enclosures classified by their function (Groups 1-3) and for the 

38 small “all other” enclosure classification (Group 4c). However, for large and medium “all 

39 other” enclosure classifications (Groups 4a and 4b), the configuration can vary widely. 

40 For that reason, these two classifications were further divided to allow for additional 

41 resolution in assigning peak HRR probability distributions. The WG agreed that 

42 assignment of peak HRR distributions based on combustible configuration requires 

43 internal inspection of the electrical enclosure. 

44  Electrical ignition size/potential: The WG agreed that the electrical ignition size and 

45 potential can be a factor in the resulting HRR, although no clear conclusions can be 

46 reached with existing experimental data. However, this factor is implicitly included in the 

47 classification process by separating the enclosures by function (Groups 1-3) from the “all 

48 other” enclosure classification (Group 4). The peak HRR probability recommended for 
OVERVIEW OF THE PROCESS 

2-6 

1 the functional electrical enclosures (Groups 1-3) considered this in the determination of 

the 75th and 98th 2 percentiles. 

3  Ventilation conditions: The WG agreed that the electrical enclosures classified by their 

4 function (Groups 1-3) are vented but closed (i.e., they have vents of some type but not 

5 open doors). Due to the inherent electrical hazards associated with these enclosures 

6 and the plant procedures governing their maintenance, the WG agreed that peak HRR 

7 probability distributions are only needed for closed electrical enclosure configurations. 

8 This is not the case for the “all other” enclosure classes, which have both open and 

9 closed configurations as evidenced by numerous enclosure pictures available to the 

10 group. Therefore, the WG developed probability distributions for both open and closed 

11 “all other” (Group 4) electrical enclosure configurations. 

12 2.2.3 Calibration Exercise 

13 A calibration exercise was conducted to ensure a common understanding of what a particular 

14 HRR value in kilowatts (kW) implies with respect to an electrical enclosure fire. This exercise 

15 involved the collection, by the NRC staff, of still photos and videos taken mainly from the most 

16 recent NRC/NIST test set [7]. The examples were chosen to illustrate a range of fire intensities 

17 and burning behaviors. During a webinar/conference call the NRC staff explained the attributes 

18 (i.e., amount of combustibles, ventilation condition, and cable insulation material type) of each 

19 example case and then showed the still photos and/or videos. Each WG member was then 

20 asked to predict the peak HRR value being illustrated. Time lapse videos were then shown of 

21 the tests, and the actual peak HRR measurement was provided to the WG. Initially, individual 

22 estimates showed wide variation, but by the end of the exercise, all members showed a good 

23 ability to estimate the peak HRR values for a particular fire size, specifically, accounting for the 

24 amount of combustibles. 

25 

26 Figure 2-1 and Figure 2-2 illustrate the fire sizes and the corresponding fire intensities in 

27 kilowatts for two examples used in the calibration exercise. Note that these are not cable 

28 insulation/enclosure fires. Nonetheless, they do visually illustrate relative fire intensities for 

29 common objects, a coffee maker and a Christmas tree, over the course of a fire test. 

30 

31 
OVERVIEW OF THE PROCESS 

2-7 

1 

2 

3 Figure 2-1 

4 Fire Size/Intensity Calibration (0 to 40 kW) 

5 

6 

7 

8 Figure 2-2 

9 Fire Size/Intensity Calibration (50 to 1000 kW) 
OVERVIEW OF THE PROCESS 

2-8 

1 2.2.4 Assessment of Electrical Enclosure Heat Release Rates 

Each member of the WG was tasked to independently assign 75th and 98th 2 percentile HRR 

3 values for the newly developed enclosure classification groups defined in Chapter 3. 

4 Consideration of specific experiments, operational experience, influencing factors, and so on 

5 were incorporated into the specific distributions on an individual basis. 

6 2.2.5 Building Consensus 

7 Using a consensus process the peak HRR distributions for each of the enclosure classification 

8 groups were defined. This activity took place during a WG meeting with all members present. 

9 Initially, for each enclosure type/function group, the members were polled regarding their 

10 individual estimates of the peak HRR distribution for that group (developed in the second step 

11 as noted above). A broad consensus was evident for most cases, with some outlier estimates 

12 on both the high and low sides. Each member was asked to describe their reasoning for each 

13 case and, as a more common understanding of the conditions being assumed and the 

14 applicable data set was developed, consensus values were proposed and agreement obtained. 

15 Through these discussions, preliminary consensus estimates were developed by the WG. 

16 Based on these preliminary consensus values, the WG fitted a gamma distribution based on the 

two HRR values corresponding to 75th and 98th 17 percentiles for each classification group (see 

18 Appendix D.3). 

19 2.2.6 Ensuring Consistency and Applicability 

20 To ensure consistency and applicability of the consensus estimates, each of the available tests 

21 was reviewed and assigned to one or more classification groups. Certain tests were discussed 

22 and, based on one or more test-specific factors, were judged to be of questionable applicability. 

23 In some cases, tests were partly discounted; that is, they were considered somewhat applicable 

24 but not directly characteristic of realistic fire conditions. No attempt was made to “weigh” the 

25 discounted tests against other tests, and the discounted tests are included in the experimental 

26 data distributions, but the final recommended peak HRR distributions typically will not bound 

27 these tests. Other tests were dismissed entirely; that is, they were not considered applicable to 

28 actual enclosures given the nature of the fuels burned and are excluded from the data sets 

29 entirely. Appendix D presents the mapping of test data to the HRR distributions chosen by the 

30 WG members based on a consensus basis. It is emphasized that the revised peak HRR 

31 distributions are not based directly on fitting any particular set of test data. However, the 

32 available test data were used by WG members to inform their selection of representative 

33 distributions. Ultimately, the consensus distributions were compared to test data considered 

34 applicable to each enclosure classification group to ensure that any inconsistencies could either 

35 be explained (e.g., based on a sparse or otherwise poor data set) or, where possible, eliminated 

36 (see Appendix D). The EPRI fire events database was then reviewed to identify that the HRR 

37 profile for the particular enclosure encompasses all plant events. 

38 

39 The cases where test data were discounted or dismissed are detailed as follows (also see 

40 Appendix D.1): 

41 

42  The original NRC/SNL electrical enclosure fire test series [8] included a small number of 

43 tests involving either a heptane fuel pool (Tests PCT-4A and PCT-4C) or a gas burner 

44 placed inside an otherwise empty control enclosure (Tests 21 and 22). These tests were 

45 never intended to represent an actual fire in an electrical enclosure; rather, they were 

46 intended to provide for characterization of room effects given a large, well-characterized 
OVERVIEW OF THE PROCESS 

2-9 

1 fire within an electrical enclosure shell. These tests were not considered relevant to 

2 characterization of actual electrical enclosure fires and were dismissed entirely. 

3 

4  One test from the original NRC/SNL test series [8] was discounted based on the non5 representative nature of the ignition source; namely, Test 23, which involved qualified 

6 thermoset cables in a bench board electrical enclosure. For Test 23, the WG agreed 

7 that the extent of the fire growth seen in this test was likely driven largely by the intensity 

8 and duration of the ignition source, which burned at roughly 40 kW for over 30 minutes. 

9 Many test programs have shown that thermoset cables require a significant and 

10 sustained ignition source or they will likely self-extinguish. Hence, the peak heat release 

11 rate in this test, estimated at 1235 kW, would not be expected given a more realistic 

12 ignition source. In general, some form of an ignition source must be used to initiate a 

13 fire test, and the test programs considered by the WG represent a range of potential 

14 ignition sources. In the case of Test 23, the WG concluded that the ignition source used 

15 is much more intense than those to be expected for a control enclosure application and 

16 that the measured peak HRR would not have been reached had a less energetic and/or 

17 shorter duration ignition source been used. Nominally, Test 23 would be assigned to the 

18 open “all other” electrical enclosure, thermoset cable type classification group. However, 

19 the test was dismissed from the data set, and the corresponding peak HRR distribution 

20 was not formulated to bound this particular experiment. 

21 

22  The NRC/SNL tests also included a test essentially identical to Test 23 except that 

23 unqualified thermoplastic cables were used; namely, Test 24 [8]. In this case, the test 

24 was included in the data set for open “all other” electrical enclosures with thermoplastic 

25 cables because thermoplastic cables do propagate fire more easily. However, this test 

26 was treated as an outlier case, again due to the nature of the ignition source. While this 

27 test was considered somewhat relevant, it was partially discounted and the 

corresponding peak HRR distribution does not bound this particular experiment2 28 . The 

29 WG concluded that given a more realistic ignition source, full electrical enclosure 

30 involvement was still possible although the fire would have likely grown at a slower pace 

31 and reached a lower peak than that observed in the test. Test 24 is included in the test 

32 data set for the large “all other” (Group 4a), open, TP cable classification group, as 

33 shown in Appendix D. 

34 

35  The majority of the IRSN tests [9, 10, 11] involved PMMA slabs burned within an 

36 electrical enclosure mock-up shell. The objective of these tests was to assess whether 

37 enclosure vent size correlated to the maximum heat release rate possible given a fire 

38 within an enclosure. The fuels in these tests are not representative of real electrical 

39 enclosures. Given the unrealistic nature of the fuels, the IRSN tests using PMMA slabs 

40 were dismissed from the peak HRR distribution development effort. 

41 

42  The tests conducted by NIST at CBD [7] were based on a catalog of pictures obtained 

43 during walkdowns of various NPPs as well as the discretion of the test engineers. Two 

44 test scenarios in particular were chosen in order to evaluate the worst-case condition 

45 beyond that typically seen in NPPs. These tests are identified as test numbers 68, 71 

46 (closed door), and 83 (open door, see Figure 2-3). The cabinets were filled with the 

47 maximum loading of jacket stripped cables and distributed in a manner to facilitate flame 

 

2

 Similarly, the NUREG/CR-6850 HRR distribution for thermoplastic, open enclosure, multiple bundles 

does not bound this experiment. 
OVERVIEW OF THE PROCESS 

2-10 

1 spread. That is, the cables were separated to allow for the maximum burning area of the 

2 fuel and to facilitate full burnout. These cases were altered to evaluate the impact of 

3 various test conditions (e.g., ventilation, configuration, and ignition) on the fire growth 

4 within the electrical enclosures. The tests were not dismissed, but they were discounted 

5 because the cable loading arrangement was not typical of any known NPP cabinet type. 

6 However, these tests provide some indication of the absolute upper bound fire 

7 conditions that might occur given the enclosure geometry. The data was used by the 

8 working group to inform the consensus distributions. These tests along with some large 

9 fire test data from the NRC/SNL tests [8] were mapped to the large and medium size 

10 enclosure classification groups. 

11 

12  The WG discounted some of the most recent NRC/NIST tests [7] based on two factors. 

13 First was the extreme ambient conditions under which the tests were conducted, and 

14 second was the fact that the smaller (1 kW and 5 kW) ignition sources used by NIST 

15 were unable to create a sustained fire under the test conditions. Most of these tests 

16 were performed with the electrical enclosures and, more importantly, the cables, at initial 

17 temperatures of 0 °C (32 °F) or less. These initial conditions likely caused some delays 

18 in, and in some cases may have prevented, cable ignition, sustained burning, and/or fire 

19 spread. Hence, while all of the NIST tests are included in at least one of the 

20 classification group test data sets, the WG chose not to include some of these tests in 

21 the experimental distributions for the other classification groups. In particular, those 

22 tests using the two smaller ignition sources (i.e., the 1 kW and 5 kW electric cartridge 

23 heaters) where the cables never ignited and no flame spread was observed were 

24 included in the small “all other” electrical enclosure (Group 4c) data set, but were 

25 excluded from the other data sets. Note that in the analysis of actual events, when 

26 estimating fire frequency, an event involving a small ignition source that self27 extinguished without any substantive fire spread would be classified as non-challenging 

28 and would be excluded from the fire frequency analysis. The WG’s decisions regarding 

29 the “no ignition, no spread” tests mirror the fire frequency analysis. 

30 
OVERVIEW OF THE PROCESS 

2-11 

1 

2 Figure 2-3 

3 HELEN-FIRE Test No. 68 

4 2.2.7 Finalizing the Consensus 

5 As a final step, the WG had an additional opportunity to consider the consensus distributions, 

6 review again the test sets associated with each classification, and propose alternative 

7 treatment, if applicable. Based on this review, the WG found that some of the HRR profiles for 

8 the “all other” – large and medium enclosures (Groups 4a and 4b) did not address certain 

9 enclosures that have combustible loads (e.g., cables) less than what is assumed as the default 

10 condition; namely, a significant fuel load relative to enclosure volume that may be arranged in a 

11 manner conducive to fire spread. To address enclosures with limited and neatly configured 

12 combustibles, the WG added two separate sub-groups for these two enclosure classes. One 

13 sub-group (i.e., low fuel loading) represents enclosures with combustible loads relatively less 

14 than that of the default case. The second sub-group (i.e., very low fuel loading) represents 

15 enclosures with very sparse combustible loads relative to enclosure volume. In both sub16 groups, it is assumed that all combustibles are neatly organized. Descriptions of these sub17 groups are presented in Section 3.2.2. The WG repeated the steps discussed in Sections 2.2.2 

18 through 2.2.7 to reach a consensus on these sub-group HRR estimates. 

19 2.3 Method for Characterizing Electrical Enclosure Fire 

20 Plumes 

21 The initial concept of the obstructed plume was discussed during the first meeting of the WG. 

22 The common treatment of fire plume effects for electrical enclosure fires completely ignores the 
OVERVIEW OF THE PROCESS 

2-12 

1 effects of the enclosure surfaces, especially the top, on plume development and is therefore 

2 quite conservative. The concept involved using Fire Dynamics Simulator (FDS) as a surrogate 

3 for experimental data to support a more realistic representation of the early stage fire 

4 development and thermal insult to fire targets located within a plume. In simple terms, FDS is 

5 used as a tool to evaluate the effect an obstruction has on fire plume thermal characteristics and 

6 supports the development of an adjustment factor for the vertical zone of influence (ZOI) and 

7 plume temperature. 

8 

9 During the first meeting the WG identified obstruction configurations, ventilation conditions, and 

10 fire size and location, along with measurements and locations to include in the FDS simulation. 

11 During the second meeting preliminary results of the FDS simulations were presented. At this 

12 meeting, the WG decided that the approach appeared to yield encouraging results to improve 

13 the realism in modeling electrical enclosure fires, compared to existing guidance in NUREG/CR14 6850. The WG suggested modifications to the electrical enclosure modeling and fire size. At 

15 the third meeting the WG determined that the work and documentation was at a level of quality 

16 to facilitate a peer review. Between the third and fourth meeting the peer review comments 

17 were received, reviewed, and incorporated into the study as appropriate. The results of this 

18 work, including the assumptions, approach, results, and correlation, are presented in Chapters 5 

19 and 6 of this report. 

20 

21 
3-1 

1 3

2 Classification of Electrical Enclosures 

3 This chapter describes the classification of electrical enclosures based on the enclosure’s 

4 electrical function, physical size and location (e.g., free standing, wall mounted), amount and 

5 character of fuel loading, ventilation characteristics, and the cable insulation material type. 

6 Section 2.1 presents the process pursued by the working group (WG) to develop these 

7 classifications. Appendix C provides photographs of a range of electrical enclosures and their 

8 installed configuration in NPPs. This section includes some illustrative examples of those 

9 photographs. 

10 

11 The classification of electrical enclosures as fire ignition sources (Bins 4, 10, and 15) in 

12 accordance with Task 6 of NUREG/CR-6850 is based on assignment of each enclosure to one 

of the following type/function classification groups1 13 : 

14 

15  Group 1: Switchgear and Load Centers 

16 

17  Group 2: MCCs and Battery Chargers 

18 

19  Group 3: Power Inverters 

20 

21  Group 4: All Other Electrical Enclosures 

22 

23 o Group 4a: Large Enclosures 

24 o Group 4b: Medium Enclosures 

25 o Group 4c: Small Enclosures 

26 

27 The fire characterizations of these enclosure classification groups are described below. Section 

28 3.1 describes the functionally based Groups 1-3 enclosures and Section 3.2 describes the 

29 classification and sub-grouping of Group 4 enclosures. 

30 

31 The discussions here are intended to highlight both similarities and differences between the 

32 various enclosure types considered. The factors highlighted in each section are those that are 

33 expected to substantially impact both the worst-case fire behaviors that might be expected (e.g., 

the 98th 34 percentile peak HRR values) and the relative likelihood that, given an ignition event and 

in the absence of fire suppression, a large fire is likely to develop (as characterized by the 75th 35 

36 percentile peak HRR values). The primary factors considered in the final group classification 

37 process are as follows: 

38 

39  Physical size: For classification Group 4, physical size is used as a general, readily 

40 obtainable characteristic that would influence fire behavior. The presumption is that a 

41 large or a medium enclosure holds the potential for higher intensity fires than a 

 

1

 Each classification group is assigned a simple alpha-numeric identifier in order to simplify aspects of the 

discussions that follow and to promote a common PRA vocabulary. It is provided that these designations 

be used as “shorthand” identifiers when citing classification results for in-plant enclosures (e.g., in fire 

PRA databases). 
CLASSIFICATION OF ELECTRICAL ENCLOSURES 

3-2 

1 comparable but much smaller enclosure simply because it has the capacity to hold more 

2 combustible fuels and more possible ignition sources. Note, however, that for 

3 classification Group 4, if visual inspection of the enclosure internals is possible, 

4 additional consideration can be given to the actual fuel load present, which may act to 

5 reduce the default fire potential of a large or a medium enclosure to, in effect, that of a 

6 smaller enclosure. 

7 

8  Cable insulation type: The HRR distributions presented in Chapter 4 distinguish 

9 between enclosures with thermoset (TS) cable insulation (including qualified TP and SIS 

10 wire) versus unqualified thermoplastic (TP) cable insulation (including enclosures with a 

11 mix of thermoset and unqualified thermoplastic). Testing has consistently shown that 

12 unqualified TP cables ignite more easily and spread fire more readily than TS cables. 

13 However, testing also shows that if a growing fire is established in an electrical 

14 enclosure such that full burn-out of the enclosure is likely (barring suppression), the peak 

15 HRRs for TS and TP cables are quite similar. In general, the working group established 

the same 98th 16 percentile peak HRR value for both cable types (with the exception of 

large open enclosures2

). However, the 75th 17 percentile peak HRR value is lower for TS 

18 cables than for TP (typically half as large). This reflects the observation that given an 

19 equivalent ignition event fire spread is less likely with TS cables than with TP cables. In 

20 other words, a larger percentage of TS cable fires are expected to remain small, even in 

21 the absence of suppression, compared to TP but, if the fire does spread, the worst-case 

22 peak HRR values are likely similar. 

23 

24  The combustible fuel load and configuration: The total fuel load in an enclosure will 

25 influence the fire behavior, especially in cases where the fuel load is especially sparse. 

26 Equally important is the configuration of the fuels present. For example, large power 

27 cables will burn far less readily than will small instrument and control wires (the “logs 

versus kindling” analogy). Similarly, testing3 28 has shown that cables that are tightly 

29 bound and routed in an orderly manner will burn less readily than would loosely bound 

30 cables routed in a disorderly fashion. 

31 

32  Enclosure ventilation condition: All other factors being equal, an enclosure with very 

33 small ventilation openings will not burn as well as a very well ventilated enclosure. The 

34 approach presented does not explicitly address the ventilation conditions of a specific 

35 enclosure. However, the peak HRR distributions are expected to bound the typical 

36 ventilation conditions for the specific equipment classification group. 

37 

38  The nature of the ignition sources present: Given the presence of higher energy 

39 ignition sources (e.g., higher power components and arc-fault sources) a higher intensity 

40 fire is more likely to develop in comparison to a similar enclosure with only low energy 

41 ignition sources present (e.g., control and instrument components). 

 

2

 Based on test results, the WG concluded that a 1000 kW fire in case of the large enclosure group with 

TP cable insulation and open door ventilation configuration would bound all worst possible enclosure 

classes that may be existing in NPPs. 

3

 This observation is consistent with both the original NRC’s cabinet fire testing in the 1980s [8] and with 

the more recent NIST tests [7]. 
CLASSIFICATION OF ELECTRICAL ENCLOSURES 

3-3 

1 3.1 Functionally Based Enclosure Groups 

2 All electrical enclosures in nuclear power plants (NPPs) are categorized based first on their 

3 electrical function and second on the cable insulation type (TP or TS). For some enclosures this 

4 is sufficient. In particular, switchgear, load centers, motor control centers, battery chargers, and 

5 inverters are all characterized based on function and fuel type alone. The following three 

6 functional groups have been defined to characterize the anticipated fire characteristics for these 

7 types of enclosures.

8 3.1.1 Group 1: Switchgear and Load Centers 

9 This type/function group includes the enclosures housing higher power electrical switching and 

interrupting devices4 10 . Switchgear and load centers are both common and readily identifiable in 

11 all plants. The term “switchgear” generally refers to medium voltage (>1000 VAC) switching 

12 equipment. The term “load center” is commonly used to describe low voltage (≤1000 VAC) 

13 switchgear. 

14 

15 Generally, load centers are physically smaller than the medium voltage switchgear and as many 

16 as four individual switches (typical) may be found to share a single vertical segment or cabinet 

as these are counted5 17 under NUREG/CR-6850. For switchgear, the switch itself is generally 

18 housed in the lower section of the enclosure (due to its weight and physical size) and the 

19 associated control and monitoring equipment is housed in the upper section of the enclosure. 

20 For load centers, the actual switch and associated control and monitoring components share a 

21 common space. Switchgear and load centers have been combined into a single classification 

22 group for fire characterization purposes based on several factors. 

23 

24 First, these devices perform essentially the same function; namely, switching and overload 

25 protection for higher power loads associated with, most commonly, a subsidiary power 

26 distribution bus. The distinctions between switchgear and load centers are mainly associated 

27 with voltage and total power per switch. 

28 

29 Second, these devices have similar ignition sources and energies present; namely, those 

30 associated with failures in the primary switching unit including its input/output power leads, and 

31 those associated with the lower voltage control and monitoring components. 

32 

33 Third, switchgear and load center enclosures typically have limited fuel loads (i.e., in 

34 comparison to most other electrical enclosures), and the characteristics of the fuels present are 

35 similar. In both cases much of the fuel load is associated with the larger diameter input/output 

36 power cables which will not burn easily but will burn given a sufficient ignition event and/or 

37 sustained fire. The balance of fuel in both device types is associated with the control and 

38 monitoring components including smaller gauge instrument and control wiring, and this fuel will 

39 burn more easily. The presence of the control and monitoring components and wiring is one of 

40 the more significant factors considered to influence the overall fire growth potential. 

41 

 

4

 Note that switchgear and load centers are subject to high energy arcing fault (HEAF) events in addition 

to general thermal fires. The discussions here are limited to thermal fires only, but the working group did 

recognize that, consistent with the event data, some thermal fires are initiated by arc fault failures that do 

not reach the energy and impact levels associated with the HEAF events. 

5

 In NUREG/CR-6850 Task 6, electrical cabinets are counted by vertical section. Hence, a single load 

center vertical section may house multiple switches. In contrast, medium voltage switchgears are 

typically housed individually; that is, there is typically only one switch per vertical section. 
CLASSIFICATION OF ELECTRICAL ENCLOSURES 

3-4 

1 Finally, both switchgear and load centers will almost certainly be found in a closed, vented 

2 enclosure configuration due to safety standards and the need to dissipate internally generated 

normal heat loads6 3 . Given similar enclosure conditions, fire characteristics will also tend toward 

4 similar behaviors. 

5 

6 Given the similarities described above, both switchgear and load centers are treated in the 

7 same manner relative to general fire characterization (again, excluding high energy arc fault 

8 treatment). Figure 3-1 provides exterior photographs of a typical bank of switchgear and load 

9 centers. 

10 

11 

12 13 Switchgear Bank Load Centers 

14 

15 Figure 3-1 

16 Switchgear and Load Center 

17 3.1.2 Group 2: Motor Control Centers (MCCs) and Battery Chargers 

18 MCCs and battery chargers are also common and readily identifiable in all plants. A typical 

19 plant will have many MCCs but typically only a handful of battery chargers. While these two 

20 device types perform markedly different functions, the two have been combined into one group 

21 for fire characterization based on similarities in size, fuel loading, and the energy available to 

22 potentially initiate a fire. 

23 

24 MCCs are commonly at the same voltage and powered from a load center. Typically, a single 

25 MCC will service a single end device such as a pump or motor. MCCs may also be used to 

26 supply lower level distribution buses such as house lighting and power. As with load centers, 

27 MCCs are commonly housed in stacks so that a single vertical section of MCCs (i.e., one 

28 cabinet as counted in NUREG/CR-6850) will commonly house four to five individual switches 

29 but could house as many as twelve individual switches. The fuel load for a typical MCC cabinet 

30 includes both the input/output power cables and control monitoring devices and wiring. In 

31 comparison to switchgear and load centers, the power cables will be smaller. While these 

32 smaller cables will burn more easily, they also represent a lower fuel loading than the larger 

 

6

 The working group consulted a number of knowledgeable experts outside the working group regarding 

these enclosure configuration assumptions and none were able to cite an exception to the enclosure 

assumptions as cited here. 
CLASSIFICATION OF ELECTRICAL ENCLOSURES 

3-5 

1 power cables associated with switchgear and load centers. The potential ignition sources also 

2 include both the power and control components. 

3 

4 One factor considered important by the working group is that an MCC is highly compartmented 

5 and this feature will limit the intensity of most MCC fires. Switchgear and load centers tend to 

6 be large enclosures with little internal partitioning. For MCCs, each individual switch is typically 

7 housed within its own enclosure (often referred to as a compartment or cubicle) and a vertical 

8 section, or stack, is made up of several compartments. In addition, each stack is commonly 

9 associated with a narrow vertical channel used to route field cables into and out of the 

10 compartments (see Figure 3-2). This channel is a common/shared portion of the MCC, and the 

11 possibility that fire might spread from one compartment into this vertical channel was a 

12 significant factor in the working group’s assessment of the worst-case fire potential. 

13 

14 

15 

16 Figure 3-2 

17 A Typical Vertical MCC Channel 

18 

19 Another factor considered important by the working group is that MCC cabinets tend to have 

20 more restrictive ventilation openings. In comparison to switchgear, for example, the heat loads 

21 associated with MCCs are much lower so that less ventilation is necessary to maintain 

22 components within operable temperatures. The limited ventilation conditions will tend to limit 

23 fire potential. However, MCCs may not be fully sealed and are subject to arc faults, albeit not at 

24 the HEAF level. An arc-fault initiated fire holds the potential to breach the MCC cabinet and the 

25 assumed fire characteristics reflect this (i.e., the arc fault may open a section of the MCC). 
CLASSIFICATION OF ELECTRICAL ENCLOSURES 

3-6 

1 

2 Figure 3-3 shows a typical bank of MCC stacks. This bank contains eight stacks and would be 

3 counted as eight vertical sections per NUREG/CR-6850. The stack on the far left contains 10 

4 individual switches, which are near the maximum possible for a typical MCC stack configuration. 

5 By contrast, the two center stacks appear to contain just two switches each. 

6 

7 

8 

9 

10 Figure 3-3 

11 A Typical Bank of MCC Cabinets 

12 

13 The second component of this functional group is battery chargers. While less common, all 

14 plants will have a limited number of battery chargers present. Note that only those battery 

15 chargers associated with banks of large, multi-cell, emergency station batteries are included in 

16 this functional group; that is, chargers tied to the battery banks counted as Bin 1 ignition sources 

17 consistent with Task 6 of NUREG/CR-6850. This group does not include small battery chargers 

18 that may be associated with individual battery-powered equipment items (e.g., emergency 

19 lighting, a skid-mounted pump or motor, diesel generator start-up batteries, or a piece of 

20 portable electrical equipment). 

21 

22 There are typically two or three battery chargers per battery bank. Battery chargers require 

23 considerable ventilation in order to dissipate internal heat loads and should not be treated as 

24 “well-sealed” electrical enclosures under typical conditions. This was considered an important 

25 factor influencing the worst-case fire potential by the working group. Battery chargers also 

26 contain significant ignition energy sources, including the potential for internal arc faults, given 

27 connections to both a significant AC input power source and the output connections to the 

28 primary battery bank itself. On the other hand, the fuel load in a typical battery charger is 

29 limited, especially in comparison to the total volume of the enclosure. The relatively low fuel to 

30 volume ratio compared to other enclosures appears to be driven by the presence of a number of 

31 relatively large components with very little fuel contribution (e.g., transformers, rectifiers, and 

32 fuses). Like MCCs, the primary fuel loads are associated with both the input/output power 

33 cables and the control and monitoring components and wiring. Figure 3-4 shows an external 

34 view of a typical battery charger. 
CLASSIFICATION OF ELECTRICAL ENCLOSURES 

3-7 

1 

2 

3 

4 Figure 3-4 

5 A Typical Battery Charger 

6 The WG concluded that the fire characteristics for MCC and battery charger enclosures would 

7 be effectively the same despite functional differences. Both types have similar physical sizes 

8 (e.g., volume) and contain similar ignition source energy potentials. MCCs tend to have higher 

9 fuel loads but limited ventilation, whereas battery chargers tend toward lower fuel loads but 

10 more open ventilation conditions. These two off-setting factors in particular led the WG to 

11 conclude that the likely fire characteristics were similar enough that, for convenience, these two 

12 functional device types can be combined into one type/function group for fire characterization 

13 purposes. 

14 3.1.3 Group 3: Power Inverters 

15 This type/function group includes those enclosures whose primary purpose is to house a DC-to16 AC power inverter. This functional group is not intended to include other electrical enclosures 

17 that happen to house one or more small power inverters such as those that might service 

18 individual circuits or devices. Given these constraints, inverters will be present in limited 

19 numbers at all plants. 

20 

21 Nominally one might anticipate that inverters and battery chargers would be quite similar given 

22 that the two devices perform complementary functions; that is, battery chargers convert AC 

23 power to DC power while inverters convert DC power to AC power. The WG found that while 

24 there are similarities, there are also important differences that are judged to significantly impact 

25 worst-case fire intensities. Like battery chargers, inverter enclosures are typically well ventilated 

26 in order to dissipate normal heat loads and should not be treated as “well-sealed” electrical 

27 enclosures under typical conditions. Further, significant electrical energy is present to act as 

28 ignition sources including both the input connections to the associated battery banks and the 

29 output connections to serviced AC distribution buses. However, the fuel loads for inverters are 

30 typically higher than those observed for battery chargers. The higher fuel load appears to be 
CLASSIFICATION OF ELECTRICAL ENCLOSURES 

3-8 

1 associated with the additional control and monitoring components and wiring associated with 

2 conditioning of the AC output power given that modern AC devices require reasonably “clean” 

3 input power to run reliably. In contrast, battery banks are more tolerant and require less 

4 rigorous signal conditioning of charger output. Based mainly on the higher quantity and general 

5 nature of the fuel loading, inverters are assigned to higher peak HRR levels than are battery 

6 chargers. Figure 3-5 shows a typical inverter including both an external and internal view. 

7 

8 9 

10 Figure 3-5 

11 A Typical Inverter Cabinet (Exterior – Left, Interior – Right) 

12 3.2 Group 4: All Other Electrical Enclosures 

13 If an electrical enclosure counted in fire frequency does not fit into one of the three functional 

14 groups defined in Section 3.1 above, it is treated using classification Group 4; namely, All Other 

15 Electrical Enclosures. Group 4 will also include the main control board (MCB). This group may 

16 encompass a wide range of enclosures including those associated with, for example, control 

17 components, instrumentation, low voltage breaker panels, lighting panels, communications 

18 equipment, individual or grouped switch/disconnect boxes, open rack panels, and alarm panels, 

19 among others. Group 4 is intended as a “catch-all” for all of the Bin 15 electrical cabinets not 

20 grouped based on function (i.e., per Section 3.1) plus the main control board (Bin 4). 

21 

22 For classification Group 4, a more complex classification basis has been defined in order to 

23 reflect differences in the fire potential for this broadly defined enclosure group. Distinctions 

24 within this group ultimately lead to seven possible classification outcomes for a given enclosure 

25 that are based on (1) the physical size and (2) the fuel loading characteristics. 

26 
CLASSIFICATION OF ELECTRICAL ENCLOSURES 

3-9 

1 3.2.1 Assignment Based on Physical Size 

2 The first aspect of the characterization process is to define the enclosure as Large (4a), Medium 

3 (4b), or Small (4c). This is a simple volume-based decision using the following criteria: 

4 

 Group 4a – Large Enclosures: an enclosure with a volume greater than 1.4 m3

 (50 ft3 5 ). 

6 

 Group 4b – Medium Enclosures: an enclosure with a volume greater than 0.34 m3 7 (12 

ft3

) but no more than 1.4 m3 (50 ft3 8 ). 

9 

 Group 4c – Small Enclosures: an enclosure with a volume of no more than 0.34 m3 10 (12 

ft3 11 ). 

12 

13 The following paragraphs provide additional discussion regarding each of these classification 

14 group categories: 

15 3.2.1.1 Group 4a: Large Enclosures 

16 This type/function group is intended to cover mainly the larger control and instrumentation 

17 cabinets that are common in many areas of the plant. This group also includes low voltage 

18 power and lighting (typically 110 or 220 VAC house power) distribution panels (i.e., breaker 

panels) if such enclosures meeting the size criteria exist in the plant7 19 . The electrical enclosures 

20 included as large enclosures may cover a wide range in terms of both physical size and 

21 function. Large enclosures would include most of the cabinets in the main control room 

22 including the main control board, but with the possible exception of some smaller computer or 

23 instrument racks if present. This group would include the typical open racks of the relay room. 

24 This group can also include a range of general electrical enclosures that may be found 

25 throughout the plant. Additional examples may include alternate shutdown panels, diesel 

26 generator control cabinets, and signal conditioning cabinets, among others. Again, the 

27 determining factor for classification as a large enclosure is the total enclosure volume, not the 

28 specific enclosure function. 

29 

30 Figure 3-6 and Figure 3-7 (see page 3-10) illustrate open and closed configurations of typical 

31 large enclosures. 

32 

 

7

 Note that the presence of a lighting or breaker panel meeting the large size criteria is considered 

unlikely and most such panels will likely fall into groups 4b and 4c. 
CLASSIFICATION OF ELECTRICAL ENCLOSURES 

3-10 

1 

2 Figure 3-6 

3 Large Enclosures (Open) 

4 

5 Figure 3-7 

6 Large Enclosures (Closed) 

7 
CLASSIFICATION OF ELECTRICAL ENCLOSURES 

3-11 

1 3.2.1.2 Group 4b: Medium Enclosures

2 This type/function group is intended to cover enclosures that are comparatively smaller than the 

3 large enclosure group but that may still contain a substantial fuel load and significant ignition 

4 sources (see Figure 3-8). This group includes a wide range of instrument and control cabinets 

5 as well as many typical low voltage (<1000V) enclosures housing power and lighting circuit 

6 breaker panels, local control panels that may service several devices, and larger alarm panels 

7 such as a large, centralized fire protection alarm/control panel that services multiple fire 

8 protection (detection and/or suppression) systems. The group might include smaller signal 

9 conditioning cabinets. This group would also include most portable rack-mount computer and 

10 instrumentation cabinets that might, again, be found in use throughout the plant. Again, for any 

11 enclosure not meeting the functional group definitions from Section 3.1, the determining factor 

12 for categorization as a medium enclosure is the enclosure volume, not the enclosure function. 

13 

14 

15 

16 Figure 3-8 

17 Medium Enclosures 
CLASSIFICATION OF ELECTRICAL ENCLOSURES 

3-12 

1 3.2.1.3 Group 4c: Small Enclosures 

2 This type/function group is intended to cover the range of small, often wall-mounted or pedestal3 mounted, local control, alarm and switching boxes that did not meet the criteria for exclusion 

4 from the electrical enclosure ignition source counting information but that, due to their size and 

5 contents, would represent minimal fire threats. This group (see Figure 3-9) would include 

6 localized motor or pump control cabinets, small house power and lighting breaker panels, 

7 terminal block cabinets that did not meet the criteria for treatment as junction boxes, and 

8 individual switch/disconnect boxes. This group would also include localized alarm, 

9 communication, or indication panels that did not meet the fire ignition source exclusion criteria. 

10 

11 

12 

13 Figure 3-9 

14 Small Enclosures (Note: top left enclosure may be well-sealed) 

15 Note that there is no explicit voltage cutoff associated with this group and the group may include 

16 items such as 480 VAC disconnect switch boxes, fuse cabinets, and power disconnect switches 

17 that are commonly housed in individual switch cabinets. For small enclosures, the WG agreed 
CLASSIFICATION OF ELECTRICAL ENCLOSURES 

3-13 

to limit the volume to no more than 0.34 m3

 (12 ft3 1 ). For an enclosure of this size, the amount of 

2 combustible materials present would be sharply limited, and such enclosures are normally found 

3 in a closed configuration. While some of these enclosures would contain significant potential 

4 ignition sources (e.g., a 480 V disconnect switch) the peak fire size would be limited by the fuel 

5 content and, for most such enclosures, the fire would be expected to remain contained inside. 

6 Even given an arc fault in a disconnect switch, which might breach the enclosure, the lack of 

7 fuel would mean that any flashover or fire would likely self-extinguish very quickly, a view 

8 supported by the event data. As a result, small enclosures are expected to present minimal 

9 threats to targets outside the box, and the provided fire characteristics reflect this assessment. 

10 3.2.2 Assignment Based on Fuel Loading Characteristics 

11 The second set of categorization criteria is limited to “Large Enclosure” and “Medium Enclosure” 

12 groups and is based on the fuel loading configuration. This second set of criteria may result in 

13 assignment of these two groups (Groups 4a and 4b) to one of three sub-groups as follows: 

14 

15  Sub-Group 4a(a) or 4b(a) – Default Fuel Loading 

16  Sub-Group 4a(b) or 4b(b) – Low Fuel Loading 

17  Sub-Group 4a(c) or 4b(c) – Very Low Fuel Loading 

18 

19 This second categorization step is not applied to “(4c) Small Enclosures” given that the small 

20 enclosures are inherently fuel limited (as discussed above). Note also that, even for (4a) Large 

21 Enclosures and (4b) Medium Enclosures, this second categorization step is optional; that is, 

22 assignment of an enclosure to the Default Fuel Loading sub-group [4a(a) or 4b(a)] is acceptable 

23 without further examination of the enclosure. The assignment of an enclosure to either the Low 

24 Fuel Loading [4a(b) or 4b(b)] or Very Low Fuel Loading [4a(c) or 4b(c)] sub-group does require 

25 visual examination of the enclosure’s internal content. Hence, if visual observation is not 

26 possible (e.g., the analyst is not allowed to open the enclosure) then the Default Fuel Loading is 

27 assumed. 

28 

29 As the names imply, the Low Fuel Loading and Very Low Fuel Loading sub-categories reflect a 

30 decreasing amount of combustibles and/or a fuel configuration less conducive to fire spread 

31 when compared with their default cases. Note that the criteria applied here are not based on a 

32 specific threshold fuel loading (e.g., total combustible mass). This is because it will be virtually 

33 impossible to determine the total fuel mass with any degree of confidence. Rather, the criteria 

34 are based on visual examination, analyst judgment, and comparison to sample photographs 

35 provided in this section and in Appendix C. The physical examination process will look for 

36 certain basic characteristics to determine the appropriate category for a given enclosure. 

37 

38 The analyst is cautioned that these considerations must include all of the fuels present within 

39 the enclosure. In particular, simply opening the access door to an enclosure does not always 

40 reveal all of the combustibles present. It is not expected that the analyst would open and 

41 examine the interior of small electrical enclosures housed within a larger enclosure (e.g., a 

42 vendor-provided electrical housing or smaller purpose-built enclosures housing a small fraction 

43 of the enclosure contents). However, in many enclosures quantities of fuels may be hidden 

44 behind intermediate partitions or component mounting panels. That is, components may be 

45 mounted onto internal partitioning panels so that they are readily accessible for service. This 

46 may be accompanied by through-wiring such that the lead cables are hidden behind the 

47 mounting panels. In some cases, opening both sides of the panel may still leave a central wire48 routing space hidden. The analysis is expected to identify such spaces, if they exist, and to 

49 include any hidden fuels in the assessment. 
CLASSIFICATION OF ELECTRICAL ENCLOSURES 

3-14 

1 

2 The easiest of the three categories to identify should be the Very Low Fuel Loading 

3 configuration; hence, this sub-group is covered first. 

4 

5 Very Low Fuel Loading 

6 Figure 3-10 illustrates two enclosures each with a very low fuel load. The enclosure on the left 

7 would be a Large Enclosure Group [4a(c)], and the enclosure on the right would be a Medium 

8 Enclosure Group [4b(c)]. 

9 

10 

11 Figure 3-10 

12 Two “Very Low Fuel Loading” Enclosures 

13 In this sub-group, the electrical enclosure should show a very sparse fuel load including 

14 consideration of all combustible materials present. There should be only a small number of 

15 cables and components present in comparison to the total enclosure volume. The combustible 

16 contents should be both limited in quantity and widely dispersed within the enclosure. The 

17 cables that are present should be neatly arranged and restrained; for example, those cables 

18 present should be routed in an orderly fashion and tied to internal restraints. The intent here is 

19 that the combustibles present should be arranged such that if a fire were to ignite somewhere in 

20 the enclosure, it would be very unlikely to spread to nearby combustibles. 
CLASSIFICATION OF ELECTRICAL ENCLOSURES 

3-15 

1 Characteristics that would preclude this categorization would include a significant loading of 

2 printed circuit cards, or the presence of components with a significant potential for energetic 

faults (i.e., arc-flash type failures with significant energy8 3 ). 

4 This category would commonly apply to a range of instrument and control cabinets (or open 

5 racks) where there are relatively few components present and each instrument, indicator, or 

6 switch is serviced by only one or two small cables. The fuels should be dispersed widely over 

7 the enclosure volume such that fire spread would be difficult to achieve. Typically, the fuel load 

8 would be limited to only face-mounted components and the wires servicing those components. 

9 Distinguishing between the Default [Sub-Groups 4a(a) or 4b(a)] and Low Fuel Loading 

10 [Subgroups 4a(b) or 4b(b)] configurations will require more judgment in application. The 

11 distinctions are based on not only the raw fuel load (e.g., total combustible mass) but also the 

12 configuration of that fuel load. That is, if the internal cable conductors are tightly bundled (no air 

13 gaps visible), and wires leading to the electrical or electronic devices are neatly organized, fire 

14 is less likely to spread. In contrast, cables in loose bundles (air gaps visible between adjacent 

15 cables) or run in Panduit (e.g., routed without ties in a vertical cable routing channel) will burn 

16 more readily and would be indicative of a default fuel load. The presence or absence of other 

17 combustible materials is also important to this assessment. In order to assess these conditions, 

18 the enclosure must be opened and an assessment must be performed. Descriptions of these 

19 two rating levels are provided below. 

20 Default Fuel Loading 

21 This would be the default assignment made to an enclosure unless the enclosure contents can 

22 be visually examined and dispositioned. A Default Fuel Loading would represent a relatively 

23 high density of fuels (i.e., in comparison to enclosure volume) which includes both cables and all 

24 other flammable materials present (e.g., circuit cards, switches, relays, etc.). The fuel may be 

25 distributed throughout the enclosure and may be arranged in a somewhat disorderly fashion. 

26 Some abandoned in place legacy cables may also be present. An enclosure with a high load of 

27 control components and/or circuit cards would typically imply a default fuel loading. 

28 Low Fuel Loading 

29 This loading implies a fuel configuration that is light and/or moderate but not conducive to fire 

30 spread. Assignment of this rating level to an enclosure implies that if a fire were to ignite, the 

31 fuel loading is such that fire development will be both slow and difficult. For example, cables in 

32 tight bundles (no air gaps visible between cables in the bundle) are more difficult to burn and 

33 are considered as one indicator of a fuel load that is not conducive to fire spread (see Figure 

34 3-11). 

 

8

 This criterion is intended to cover items with voltages in excess of 125 VDC or 220 VAC. All devices 

have some potential for arcing, including a light switch. The intent here is to cover only those devices 

with a significant arc flash potential, e.g., ones that would require personal protective equipment per 

appropriate IEEE standards. 
CLASSIFICATION OF ELECTRICAL ENCLOSURES 

3-16 

1 

2 Figure 3-11 

3 Large Enclosure (Closed and Open Configurations): Example of a “Low Fuel Loading” 

4 Subgroup 

5 

6 To assist in the decision making process, Table 3-1 provides information that may be used to 

7 assign the Default Fuel Loading versus Low Fuel Loading ranking to a given enclosure. Note 

8 that both sets of criteria must be met for assignment to a lower fuel loading condition. If one set 

9 of criteria is met and the other is not, the Default Fuel Load ranking would apply. 

10 
CLASSIFICATION OF ELECTRICAL ENCLOSURES 

3-17 

Table 3-1 

Distinguishing Characteristics for Default versus Low Fuel Loading Conditions 

Characteristic Conditions Indicative of 

Default Fuel Loading 

Conditions Indicative of 

Low Fuel Loading 

Fuel Loading 

Level and Fuel 

Types 

There is a relatively high content of fuels 

including both cables and other 

combustible materials, or there is a 

significant load of printed circuit cards 

present. 

Bundles of excess or spare cable may 

be present (e.g., loops of excess or 

spare cable often found in the bottom of 

the enclosure). 

There is a relatively heavy load of 

smaller diameter (e.g., light power, 

control, or instrument) cables present 

where the cable jackets have been 

stripped and individual conductors 

routed to teminations within the 

enclosure. This would include higher 

load termination or terminal block 

cabinets, breaker cabinets, fuse 

cabinets, switching transfer cabinets, 

etc. 

The fuel load is at most moderate and is 

comprised mainly of cables. There are 

no, or at most a handful of, open or 

exposed printed circuit cards present. 

Or, 

If combustibles other than cables are 

present in moderate quantities (e.g., 

circuit cards or other components) they 

are housed in closed metal boxes within 

the larger enclosure. These internal 

boxes may be vented, but should not 

have any fully open sides (e.g., an openback rack mount circuit card cabinet 

would not meet this criterion). 

Cable Bundling 

Arrangment 

Cables may or may not be bundled. If 

cables are bound or bundled, air gaps 

between cables are evident (i.e., the 

bundles are not tight). 

Cables may be routed in cable wireways (e.g., Panduit) but are not tightly 

bound within the wire-way. 

Cables may also hang loosly in the 

enclosure with little or no restraint. 

Cables leading into the enclosure may 

be tightly bundled, but the wires leading 

to individual components are not. For 

example, when the cables are stripped 

of their jackets, the individual conductors 

are routed to their terminations in a 

somewhat disorderly fashion (e.g., 

without restraint or in loose bundles). 

Cables will be routed in tight bundles (no 

air gaps evident between cables) and in 

an orderly manner. Bundles will be 

separated from each other and will be 

secured to internal panel elements (e.g., 

structural supports or other internals). 

If cable wire-ways (e.g., Panduit) are 

used, the cables in the wire way are 

tightly bound within the wire-way. 

Wires or individual conductors leading to 

internal components are also tightly 

bundled, are arranged in an orderly 

manner, and are secured to supporting 

elements (e.g., panels or support 

structures). 

1 

2 

4-1 

1 4

2 Peak Heat Release Rates for Electrical Enclosures 

3 This chapter describes the peak heat release rate (HRR) probability distributions provided by 

4 the working group (WG). The process used to develop these probability distributions is 

5 discussed in Chapter 2. 

6 

For each enclosure type as defined in Chapter 3, a gamma distribution was fitted to the 75th 7 and 

98th 8 fire intensity values which were defined based on the consensus process described in 

9 Section 2.2. The consensus peak HRR distributions are all defined as gamma distributions, 

10 largely as a matter of convenience but also because the characteristics of the gamma 

11 distribution match desired characteristics of the peak HRR distribution. In particular, the 

12 distribution is strictly positive, and second, the likelihood of large fires becomes very small. The 

13 distributions for the three functional classification groups (Groups 1, 2, and 3) are defined in 

14 Table 4-1. 

15 

16 Included in the table are the shape parameter, alpha (α), and rate parameter, beta (β), 

characterizing each gamma distribution. Also given are the corresponding 75th and 98th 17 

percentile HRR values. The 98th 18 percentile value is the peak HRR value provided for use in the 

19 fire ignition source screening Task 7 from NUREG/CR-6850. That is, as with the original 

NUREG/CR-6850 values, the 98th 20 percentile represents the worst-case peak fire intensity for 

21 each classification group. That is, the analyst is not expected to postulate fire intensities in 

excess of the 98th 22 percentile value. 

23 
PEAK HEAT RELEASE RATES FOR ELECTRICAL ENCLOSURES 

4-2 

1 

Table 4-1 

Peak HRR Distributions for Functionally Based Classification Groups 1, 2, and 3 

Enclosures 

Classification Group Fuel Type* 

(TS or TP) Alpha Beta 

75th 

Percentile 

(kW) 

98th

Percentile 

(kW) 

1 – Switchgear and 

 Load Centers 

TS 0.32 79 30 170 

TP 0.99 44 60 170 

2 – MCCs and 

 Battery Chargers 

TS 0.36 57 25 130 

TP 1.21 30 50 130 

3 – Power Inverters 

TS 0.23 111 25 200 

TP 0.52 73 50 200 

Notes: 

It is assumed that, based on electrical code and personnel safety compliance requirements, all 

switchgear, load centers, MCCs, battery chargers, and power inverters would be normally 

closed enclosures that are opened only when under service. For these electrical enclosures 

no open enclosure fire condition has been provided for and should not be assumed given a 

normally closed condition. If a normally open enclosure of these types is encountered, the 

closed enclosure distributions presented here would not apply. 

* Per Sections 1.3 and 2.2.2, qualified TP cables (cables that have been tested and passed 

the IEEE-383 vertical flame spread test) and SIS wire may be mapped to the TS fuel type 

groups. 

2 

3 Also note that these revised distributions only characterize the peak HRR values. It is 

4 presumed that the analysis will include, as necessary to the analysis goals, consideration of the 

5 transient nature of the fire development process (i.e., growth to the peak HRR over time, steady 

6 burning, and fuel burnout). The new peak HRR distributions presented here are, by intent, 

7 compatible with the commonly applied methods of fire analysis in this regard. 

8 

9 In practice, for any given electrical enclosure, the enclosure is first categorized in accordance 

10 with Chapter 3 and placed into one of the available type/function classification Groups 1 through 

11 4. The cable type present in the enclosure is classified in one of two groups. The first group is 

12 cable that is either thermoset (TS) or qualified thermoplastic (TP). The second group is 

13 unqualified thermoplastic (TP) cable. For classification Group 4 enclosures, the sub14 categorization process based on fuel loading and configuration may also be applied (i.e., 

15 defining as Default Fuel Loading, Low Fuel Loading, or Very Low Fuel Loading). If this process 

16 is not applied, then the default categorization will apply. The distributions for classification 

17 Group 4 are defined in Table 4-2, including both the size and fuel characterization aspects of 

18 Group 4. 
Table 4-2 

Peak Heat Release Rate Distributions for Classification Group 4 (All Other) Electrical Enclosures 

Enclosure 

Class/Function 

Group 

Enclosure 

Ventilation 

(Open/ 

Closed 

Doors) 

Fuel Type* 

(TS/TP 

Cables) 

Gamma Distribution Characteristics 

(a) Default (b) Low Fuel Loading (c) Very Low Fuel Loading 

Alpha Beta 

75th

Percentile 

(kW) 

98th

Percentile 

(kW) 

Alpha Beta 

75th

Percentile 

(kW) 

98th

Percentile 

(kW) 

Alpha Beta 

75th

Percentile 

(kW) 

98th

Percentile 

(kW) 

4a – Large 

Enclosures 

>1.42 m3 

(>50 ft3) 

Closed TS 0.23 223 50 400 0.23 111 25 200 0.38 32 15 75 Closed TP 0.52 145 100 400 0.52 73 50 200 0.88 21 25 75 

Open TS 0.26 365 100 700 0.26 182 50 350 0.38 32 15 75 Open TP 0.38 428 200 1000 0.38 214 100 500 0.88 21 25 75 

4b – Medium 

Enclosures 

≤1.42 m3 

(50 ft3) and 

> 0.34 m3 (12 

ft3) 

Closed TS 0.23 111 25 200 0.27 51 15 100 0.88 12 15 45 Closed TP 0.52 73 50 200 0.52 36 25 100 0.88 12 15 45 

Open TS 0.23 182 40 325 0.19 92 15 150 0.88 12 15 45 Open TP 0.51 119 80 325 0.30 72 25 150 0.88 12 15 45 

4c – Small 

Enclosures 

≤ 0.34 m3 (12 

ft3) 

Not 

Applicable TS/TP 0.88 12 15 45 The fuel load characterization approach is not applicable to small enclosures. 

Notes: 

1. Sub-categories Column (b): Low Fuel Loading and Column (c): Very Low Fuel Loading may require opening enclosure doors to assess the internal 

configuration consistent with the discussions in Section 3 of this report. 

2. The open control cabinet condition would include open instrument racks (if they were considered potential fire ignition sources), open relay racks, openback main control room cabinets, and cabinets that are open to a service walkway (e.g., the intermediate walkway present between the front and back 

sections of a main control board at some plants). Enclosures with doors made out of combustible materials (e.g., plastic, Plexiglas, cloth) should be considered open during a fire. 

* Per Sections 1.3 and 2.2.2, qualified TP cables (cables that have been tested and passed the IEEE-383 vertical flame spread test) and SIS wire may be 

mapped to the TS fuel type groups. 

____________________________________________________________________________ 

PEAK HEAT RELEASE RATES FOR ELECTRICAL ENCLOSURES

4-3
PEAK HEAT RELEASE RATES FOR ELECTRICAL ENCLOSURES 

4-4 

1 4.1 Practice for Establishing Fire Diameter 

2 Fire plume correlations, including the Heskestad plume temperature correlation, require that the 

3 user specify a fire diameter (or area) in a fire model. The selected fire diameter can significantly 

4 impact the resulting calculations. NUREG/CR-6850 does not provide any information on fire 

5 diameter, leaving the choice to analyst judgment. FAQ 08-0043, Location of Fires within 

6 Electrical Cabinets, provides some related guidance by recommending assumed locations for 

7 modeling electrical enclosure fires. Fire locations are specified based on the presence and 

8 configurations of the vents and potential for failure of the enclosure doors. While in some 

9 instances the area of the base of the fire might be assumed equal to the vent area, the FAQ 

10 does not directly address this issue. 

11 

12 Since publication of NUREG/CR-6850, a verification and validation (V&V) of fire models for use 

13 in PRA applications has also been completed and reported in NUREG-1824 (EPRI 1011999) 

14 [20]. As a part of the effort, a specific group of experimental data sets was used as the basis for 

15 model validation; hence, the parameter range represented by the applied experimental data 

16 sets defines the range over which the validation results are applicable. That information 

17 provides an opportunity to characterize a range of appropriate fire diameter values that would 

18 fall within the validation range of the V&V report. 

19 

Specific to the case of fire plume calculations, a non-dimensional group called ‘Q*

d’ is defined1 20 

21 as follows: 

22 

Q*

d = Q / [ρ∞ · cp∞ · T∞ · g1/2 · D5/2 23 ] (4-1) 

24 

25 Where: 

26 Q = fire heat release rate (kW) 

ρ∞ = ambient air density (~1.2 kg/m3 27 ) 

28 cp∞ = specific heat ambient air (1.0 kJ/kg·°K) 

29 T∞ = ambient temperature (~293 °K) 

g = gravitational acceleration (9.8 m/s2 30 ) 

31 D = fire diameter (m) 

32 

33 This group is related to the “Froude Number” which characterizes the ratio of momentum driven 

34 flows to buoyancy driven flows and is especially relevant to plume fire behavior. A high value of 

35 this dimensionless group implies a fire with a relatively small diameter compared to the fire 

36 intensity; that is, a largely momentum driven fire plume. In the extreme, a high value would 

37 imply a jet fire. Conversely, a low number implies a fire that is dispersed over a wide surface in 

38 comparison to fire intensity; that is, a largely buoyancy driven fire plume. As stated in the V&V 

report, a typical value of Q* 39 d is on the order of 1.0. The validated range is 0.4-2.4 (see the 

40 second row of Table 2-5 in Volume 1 of NUREG-1824, EPRI 1011999 [20]). 

41 

42 Using this information, it is possible to characterize the relationship between fire intensities (i.e., 

43 HRRs) and the range of fire diameters that fall within the validation basis provided by NUREG44 1824, EPRI 1011999 [20]. In practice, when given a particular fire intensity value the implied 

45 range of fire diameter values that would fall within the bounds of the NUREG-1824, EPRI 

46 1011999 validation basis can be calculated. 

47 

 

1

 See the first row in Table 2-4 of Volume 1 of NUREG-1824, EPRI 1011999 [20]. 
4-5 

1 

2 

To do this, it is easiest to re-order Equation 4-1 to solve for D as a function of Q and Q* 3 d as 

4 follows: 

5 

D = [Q / (C1 · Q*

d)] 2/5 6 (4-2) 

7 

8 Where: 

C1 = ρ∞ · cp∞ · T∞ · g1/2 9 (4-3) 

10 

Using this modified relationship and the maximum and minimum values of Q* 11 d represented in 

12 the V&V experimental data sets (i.e., 2.4 and 0.4), the range of diameter values is easily 

calculated. Note again that the minimum diameter is associated with the maximum value of Q* 13 d

14 and vice versa. The results for a range of fire intensities are shown in Table 4-3 and the same 

15 results are plotted in Figure 4-1. Also, Table 4-4 provides minimum and maximum fire diameter 

values specific to each of the unique 98th 16 percentile HRR values provided by the WG in Table 

17 4-1 and Table 4-2 for electrical enclosures. 

18 

19 Table 4-3 

20 Range of Fire Diameters as a Function of Fire Intensity (HRR) That Remain Within the 

21 Validation Range for the Plume Correlations 

Fire Intensity 

HRR Values 

(kW) 

Minimum 

Fire Diameter 

Q*

d = 2.4 

(m) 

Maximum 

Fire Diameter 

Q*

d = 0.4 

(m) 

5 0.0814 0.1668 

10 0.1075 0.2200 

25 0.1550 0.3175 

50 0.2046 0.4189 

100 0.2699 0.5527 

250 0.3894 0.7974 

350 0.4455 0.9123 

500 0.5139 1.0522 

700 0.5879 1.2038 

850 0.6354 1.3010 

1000 0.6780 1.3884 
PEAK HEAT RELEASE RATES FOR ELECTRICAL ENCLOSURES 

4-6 

1 

2 Figure 4-1 

3 A Graphical Representation of the Data in Table 4-3 

4 

5 Table 4-4 

Minimum and Maximum Fire Diameter Values for the 98th 6 Percentile HRR Values Cited in 

7 Tables 4-1 and 4-2 

98th Percentile 

HRR Values 

(kW) 

Minimum 

Fire Diameter 

Q*

d = 2.4 

(m) 

Maximum 

Fire Diameter 

Q*

d = 0.4 

(m) 

45 0.1961 0.4016 

75 0.2406 0.4926 

100 0.2699 0.5527 

130 0.2998 0.6139 

150 0.3175 0.6501 

170 0.3338 0.6834 

200 0.3562 0.7293 

325 0.4325 0.8857 

350 0.4455 0.9123 

400 0.4700 0.9624 

500 0.5139 1.0522 

700 0.5879 1.2038 

1000 0.6780 1.3884 

8 
4-7 

1 4.2 Special Fuel Loading Configurations 

2 There are three special fuel loading configuration cases that could impact the assignment of a 

3 Group 4 electrical enclosure to the Default Fuel Loading, Low Fuel Loading, or Very Low Fuel 

4 Loading sub-group. In particular, there are certain cable routing configurations that would limit 

5 the exposure of fuels that may be present or that would eliminate potential ignition sources. 

6 These special configurations may be taken into consideration during the assignment process, 

7 as described in the follow paragraphs.

8 4.2.1 Special Case 1: No Ignition Sources Present 

9 The first special case is an electrical enclosure that has no ignition sources present. This 

10 condition will likely not be obvious based on external examination. Hence, an enclosure 

11 counted during the initial ignition source counting process may need to be reconsidered if this 

12 special case does apply. 

13 

14 A limited number of electrical enclosures found in nuclear power facilities may be effectively 

15 empty on internal inspection. These may be enclosures that once housed plant equipment but 

16 at some point were emptied and abandoned, enclosures installed as spare compartments 

17 against future need, or enclosures that only contain cables routed to other electrical enclosures 

18 or floor elevations (i.e., a cable pass-through with no terminations or end devices present). 

19 

20 In addition, enclosures containing some level of cables and components may be found that 

21 have been fully and permanently de-energized and are no longer in use. In the case of 

22 electrical enclosures, the fire ignition source is universally electrical in nature. Hence, without 

23 electrical energy present, there is no fire potential. Note that this particular case would not be 

24 applicable to an enclosure that is de-energized during some modes of plant operation but 

25 energized during others. Current methods do not extend to special treatment for such 

26 enclosures and it is not the intent of this method to address such cases. However, an enclosure 

27 that has been fully and permanently de-energized can be considered to have no ignition 

28 sources present. 

29 

30 Figure 4-2 provides an example of an enclosure that only contains pass-through electrical 

31 cables and some abandoned panel wiring (no terminations, no end devices). Since no ignition 

32 sources are present in the enclosure, it should not be counted as an ignition source and hence, 

33 no heat release rate would be assigned to it. It is provided that if such an enclosure is 

34 encountered, it should be removed from the list of ignition sources (i.e., it would no longer be 

35 considered as a potential source of a fire scenario). It is also provided that removal from the 

36 analysis be documented carefully including the basis for the decisions taken. 

37 
PEAK HEAT RELEASE RATES FOR ELECTRICAL ENCLOSURES 

4-8 

1 

2 

3 

4 Figure 4-2 

5 Cropped Photo of Electrical Enclosure with Bundled Panel Wiring and Cable, Limited 

6 Combustible Loading, and No Ignition Sources 

7 

8 4.2.2 Special Case 2: Cables Enclosed in Conduits 

Rigid metal conduit2 9 , flexible metal conduit (FMC), and liquid-tight flexible metal conduit (LFMC) 

10 are raceways of circular cross-section made from either metal tube or, in the case of flexible 

11 conduits, helically wound, formed, interlocked metal strips. Analysts may find that on internal 

12 inspection, the cables within an electrical enclosure are contained in such conduits. The use of 

13 flexible conduit within an enclosure is more likely than rigid conduit, but the use of rigid conduit 

14 cannot be precluded. 

15 

16 In general fire PRA practice, cables that are enclosed in metal conduit (rigid or flexible) are 

17 considered potential damage targets but are not considered to contribute to fuel loading or fire 

18 spread. Extending this concept to electrical enclosures, it is provided that in assessing the fuel 

 

2

 Rigid metal conduit, as that term is used here, is intended to include a range of products including actual 

rigid metal conduit (RMC) which is thick-walled threaded tubing, galvanized rigid conduit (GRC), 

intermediate metal conduit (IMC), electrical metallic tubing (EMT), and aluminum conduit. 
4-9 

1 load, do not include cables that are routed in rigid or flexible metal conduit. That is, such cables 

2 do not need to be considered as adding to the cabinet fuel load. The other criteria for 

3 assignment to a particular fuel configuration (default, low, or very low) would apply based on 

4 any other combustibles present (e.g., cable not in conduit or other components). 

5 

6 LFMC differs from FMC in that the former has an outer liquid-tight, non-metallic, sunlight7 resistant jacket over an inner flexible metal core. This outer jacket is typically a fire retardant 

8 polyvinyl chloride (PVC) thermoplastic that is of very low flammability. The flexible conduit 

9 provides a barrier between the energized insulated electrical conductors internal to the flexible 

10 conduit and external combustible materials within the electrical enclosure. Cables routed in 

11 LFMC will burn less intensely than would cables routed randomly within an enclosure. Hence, 

12 the LFMC is also considered a routing configuration that is less conducive to fire development 

13 (e.g., similar to tight versus loose bundles). 

14 

15 It is provided that while cables routed in LFMC cannot be dismissed as a contributor to fuel load 

16 entirely (because of the outer jacket), if most of the cables present are routed in LFMC this 

17 would generally allow for one step down in the fuel loading configuration assignment provided 

18 other assignment criteria are met. The presence of a small percentage of exposed cables 

19 would be permissible, but regardless, the criteria associated with the lower fuel configuration 

20 assignment must be met. That is: 

21 

22  An enclosure that might otherwise be classified as a Default Fuel Loading might be 

23 reduced to a Low Fuel Loading provided the other criteria for Low Fuel Loading are also 

24 met (Table 3-1). 

25  An enclosure that could be assigned to the Low Fuel Loading group might be reduced 

26 to a Very Low Fuel Loading, again, provided the other criteria for Very Low Fuel 

27 Loading are also met (Table 3-1). 

28  An enclosure already assigned a Very Low Fuel Loading would remain a Very Low Fuel 

29 Loading enclosure. 

30 

31 Figure 4-3 illustrates two enclosure sections where flexible conduit is used exclusively to route 

32 panel wiring and electrical cables. The picture on the left in Figure 4-3 would likely fall into a 

33 Default Fuel Loading configuration if all the cables were exposed. Given the use of LMFC, the 

34 fuel loading assignment would be reduced to Low. The picture on the right in Figure 4-3 shows 

35 an enclosure where the cables are routed in FMC (in this case not LMFC). In this case, the 

36 consideration of the other fuels present would be necessary before an assignment can be 

37 made, but the cables in the FMC would not be included in the fuel load. Based on what is 

38 visible in the picture, the fuel loading assignment would likely be Low initially if all of the cables 

39 present were exposed. Excluding the cables in FMC from the fuel load may allow for a 

40 reduction to Very Low Fuel Loading depending on the nature of the fuels present in the metal 

41 enclosed wire-ways (see discussion of wire-ways below). 

42 

43 As always, it is provided that proper documentation be included and maintained with the fire 

44 PRA records. 

45 
PEAK HEAT RELEASE RATES FOR ELECTRICAL ENCLOSURES 

4-10 

1 2 

3 Figure 4-3 

4 Photograph of LFMC (left) and FMT (right) Within Electrical Enclosure 

5 

6 4.2.3 Special Case 3: Metal Enclosed Wire-Ways and Switch/Device 

7 Covers 

8 Especially in later vintage plants, the inclusion of a design philosophy of train separation within 

9 an electrical enclosure included the use of metal enclosed wire-ways, switch covers, or device 

10 covers to separate redundant trains of insulated electrical conductors and cable. Examples of 

11 metal enclosed wire-ways and switch/device covers are shown in Figure 4-4 and Figure 4-5. 

12 This configuration is similar in some ways to the use of metal conduit, although the wire-ways 

13 typically have a larger cross-section than the conduits likely to be found inside an enclosure. 

14 The wire-ways and switch/device covers are also designed with removable covers that allow for 

15 access to the enclosed wiring. Finally, the wire-ways may include a limited degree of ventilation 

16 but are enclosed such that air flow into and out of the wire-way is sharply restricted. Despite 

17 these differences, the use of enclosed metal wire-ways or switch/device covers is considered to 

18 reduce the fire potential for an electrical enclosure in much the same way that conduits do. 

19 Figure 4-4 

20 Photograph of Metal Enclosed Wire-Ways Within Electrical Enclosure (MCB) 
4-11 

1 

2 

3 

4 Figure 4-5 

5 Photograph of Switch/Devices Cover (Labeled B) Within an Electrical Enclosure 

6 

7 In those enclosures where metal enclosed wire-ways are used to route cables, the same 

8 approach as that described above for LFMC is provided (see the three examples for LFMC cited 

9 immediately above). That is, given that most of the cables present are routed in metal enclosed 

10 wire-ways or secured in switch and/or device covers, the fuel loading configuration assignment 

11 may be reduced by one step. The presence of a small percentage of exposed cables would be 

12 permissible, but regardless, all of the other criteria for the lower fuel configuration assignment 

13 must be met. For the cases shown in Figure 4-4 and Figure 4-5, the final fuel loading 

14 assignment would likely be either Low Fuel Loading or Very Low Fuel Loading depending on the 

15 details of the other fuels present (which cannot be easily discerned from the picture). 

16 

17 Note that this special case does not extend to non-metallic (e.g., plastic or fiberglass) wire-ways 

18 or to metallic wire-ways that are substantially ventilated. That is, these are installed wire-ways 

19 that are not enclosed, but rather, have large and regular openings (essentially alternating 

20 between solid “fingers” and open gaps) that allow for wire/cable entry and exit. Based on both 

21 photographs and the experience of the working group members, wires are often routed within 

22 such wire-ways in a loose arrangement of individual insulated conductors rather than in tightly 

23 bound bundles. A fire within such a wire-way might spread as easily as a fire in a loose cable 

24 bundle given ready access to oxygen and a high degree of exposed fuel surface area. Further, 

25 a non-metallic wire-way itself represents combustible fuel, albeit likely of a low flammability. 

26 While the use of non-metallic and/or highly ventilated wire-ways may impact fire behavior, there 

27 is currently no experimental basis for assessing the effects, and the effects may not be positive 

28 (i.e., they may not reduce fire potential, depending on details of the Installation). Hence, the 

29 working group decided that non-metallic and/or substantially ventilated wire-way systems would 

30 not qualify for this special case. An example of a ventilated wire-way that would be excluded 
PEAK HEAT RELEASE RATES FOR ELECTRICAL ENCLOSURES 

4-12 

1 from this special case (i.e., the wires in the wire-ways would be counted as exposed fuel) is 

2 shown in Figure 4-6. Likewise, substantially ventilated switch and/or device covers would be 

3 excluded from this special case for the same reasons. An example of a ventilated switch and/or 

4 device covers is shown in Figure 4-7. 

5 

6 

7 Figure 4-6 

8 An Example of Non-Enclosed Wire-Ways That Would Not Qualify as Metal Enclosed Wire9 Ways 

10 
4-13 

1 

2 Figure 4-7 

3 An Example of Substantially Ventilated Switch and/or Device Covers That Would Not 

4 Qualify for Reduction 

5 

6 As a final note, these three special configurations are not mutually exclusive. For example, the 

7 picture on the right in Figure 4-4 shows an enclosure section that actually includes both FMC 

8 and metal enclosed wire-ways. This is not unexpected, and the conditions should be evaluated 

9 consistently with the aggregate conditions as they exist. 

10 

11 

12 

5-1 

1 5

2 Correlation of Obstructed Plume Models with 

3 Heskestad Plume Predictions 

4 This chapter describes the methodology used in characterizing axisymmetric fire plume models 

5 for enclosure fires. The Heskestad correlation is used as a basis for comparison of the 

6 obstructed plume predictions using the Fire Dynamics Simulator (FDS) computer software. 

7 Appendix E presents all results of the computer simulation studies representing obstructed and 

8 unobstructed plume effects, bias and uncertainty evaluation, sensitivity analysis of an opening 

9 on the top obstruction plate, and the sensitivity study of vertical source configuration. 

10 5.1 Assumptions and Limitations 

11 The Heskestad fire plume correlation is used for characterizing axisymmetric fire plumes [22, 

12 34] as a basis for comparison of the obstructed plume model predictions from the FDS 

13 computer simulations. The following reasons are taken into consideration: 

14 

15  The Heskestad correlation is a widely used model for calculating fire plume 

16 temperatures [4, 15, 18, 20, 34]; 

17  The Heskestad correlation has been verified and validated for commercial nuclear power 

18 plant applications [18, 20, 21]; 

19  As an algebraic mathematical model, the Heskestad correlation can be easily evaluated 

20 and applied for the purposes of this research and for fire PRA applications; and 

21  A review of a multitude of thermal plume correlations by Beyler [28] concluded that 

22 several reported correlations utilize a nearly identical approach to that utilized by 

23 Heskestad. 

24 

25 Note that the Heskestad correlation assumes axisymmetric plumes with the source of energy 

26 concentrated at a point in space near the base of the fire (i.e., the virtual origin). Consequently, 

27 this study includes fires modeled as axisymmetric plumes compared with FDS simulations with 

28 similar fire sources impacted by obstructions. 

29 5.1.1 Fire Dynamics Simulator 

30 Although the Fire Dynamics Simulator (FDS) is routinely used for solving practical fire problems 

31 in fire protection engineering, including fire reconstruction investigations, sprinkler design, and 

32 smoke management, it is also useful as a tool to study fundamental fire dynamics and 

33 combustion [30], including low speed transport of heat and combustion products from fire. This 

34 latter purpose serves as motivation for using FDS Version 6.0.1 as the source of the fire plume 

35 simulations developed in this study. 

36 

37 The following reasons justify the use of FDS Version 6.0.1: 

38  FDS provides the flexibility to model the scenarios with the selected influencing factors 

39 required for supporting the study of obstructed plume flows. 
CORRECTION FOR ZONE OF INFLUENCE DUE TO OBSTRUCTED PLUME EFFECT

5-2 

1  FDS has been verified and validated for commercial nuclear power plant applications 

2 [21]. NIST updates the FDS verification and validation (V&V) study with each new 

3 version release [33]. 

4  There is precedent in the commercial nuclear industry in using FDS for NFPA 805 

5 applications. For example: 

6 o An FDS simulation provides the technical basis in the approach described in fire 

7 PRA FAQ 13-0004 [24] dealing with “sensitive electronics” inside electrical 

8 cabinets. 

9 o A number of fire PRAs have used FDS in support of the fire modeling 

10 calculations for estimating time to control room abandonment due to fire 

11 generated conditions. 

12  In comparison to an experimental program, FDS models can be revised and reproduced 

13 at very little cost or time delay. 

14  FDS base case simulations for fire plumes (i.e., unobstructed plumes in the application 

15 described here) have been compared with fire plume temperature correlations as a 

16 benchmark. 

17 o In Section 5.2, FDS results of baseline unobstructed configurations are 

18 compared to the Heskestad correlation to demonstrate consistent predictions 

19 between the two models. 

20 o Also in Section 5.2, FDS results of obstructed configurations are compared to the 

21 Heskestad correlation to demonstrate that the obstruction may reduce the plume 

22 temperature significantly. 

23 o In Section 5.3, FDS results of obstructed configurations are compared to FDS 

24 results of the unobstructed configurations to identify systematic functional trends 

25 in the data (e.g., construction type, fire base height, fire diameter, etc.). 

26 o In Section 5.3.7.1, all of the results are compared using statistical analysis in 

27 order to develop appropriate guidance for the treatment of obstructed plumes 

28 using a modified Heskestad correlation. 

29 5.1.2 Zone of Influence Applicability 

30 The information developed here applies to determining the fire plume component (i.e., vertical 

31 ZOI distance and potential horizontal shift of the plume) generated in the initial stages of the fire. 

32 The analysis does not include room heat up effects (i.e., development of a room hot gas layer). 

33 The scope of this analysis is limited to the evaluation of a fire plume that is not influenced by the 

34 presence of walls or ceiling of the surrounding compartment. This limitation prevents any direct 

35 evaluation of the potential effects of an obstructed plume on the development of a room hot gas 

36 layer. The practical implication of this is that the information is focused on the “early stages” of 

37 a fire where substantial smoke accumulation and room heat up has not yet occurred. This 

38 limitation also prevents any direct evaluation of the potential effects of an obstructed plume on 

39 the smoke visibility reduction in a compartment. Existing guidance for the evaluation of smoke 

40 visibility reduction is still applicable and should be used without modification. 

41 This analysis also does not provide any justification to alter the treatment of the thermal 

42 radiation horizontal ZOI. The existing guidance provided in NUREG/CR-6850, and NUREG/CR43 6850 Supplement 1, should be used to determine the thermal radiation horizontal ZOI. 
CORRELATION OF OBSTRUCTED PLUME MODELS WITH HESKESTAD PLUME 

PREDICTIONS 

5-3 

1 Implications on the maximum extent of the vertical and horizontal ZOI due to an obstructed 

2 plume will be discussed in Chapter 6. 

3 5.1.3 Flame Height 

4 The effect that an obstruction may have on flame height has not been previously investigated. 

5 In many cases the flames impinge upon or encompass the obstructions. The maximum extent of 

6 the vertical ZOI includes contribution from both the flame impingement region and the plume. 

7 The outcome of this study will have no impact on damage predictions for targets exposed to 

8 direct flame impingement. More advanced techniques that utilize event tree analysis to credit 

9 the delay in damage states have to carefully consider the treatment of the flame impingement 

10 zone using the existing information in NUREG/CR-6850. 

11 5.1.4 Types of Obstructions 

12 The obstructions modeled in this investigation represent electrical enclosure surfaces, including 

13 the enclosure top and, in some cases, the side walls of the enclosures. The top obstructions 

14 are located within the flame, intermittent, and plume regions of the fire source. Ratios of mean 

15 flame height, L, as determined using the correlation provided by Heskestad (Equation 5 in Ref. 

16 22) to the elevation of the top obstruction (H = 2.3 m (7.5 ft)) range from L/H = 0.22 to 2.06. 

17 These obstructions are considered to be in the near-flame region most appropriate for NPP 

18 applications, and are representative of a typical enclosure height evaluated in fire PRAs. Side 

19 obstructions have been implemented in a way that would demonstrate their effect on the 

20 thermal plume without appreciably limiting the supply of oxygen to the fire source. The 

21 configurations explored here emphasize the effect of the top surface, while also considering the 

22 possibility that side surfaces may produce increased thermal exposures. 

23 

24 The obstructions modeled in this investigation include top obstructions without any openings. A 

25 number of sensitivity simulations are performed using openings of various percentages of the 

26 obstruction top surface area. These additional simulations are used to determine applicability of 

27 information when applied to enclosures with openings at the top. 

28 5.1.5 Other Applicability Limitations 

29  The methodology described in Chapters 5 and 6 of this report (i.e., the evaluation 

30 temperatures associated with obstructed fire plume flows) is provided for scenarios 

31 involving fires in open or closed electrical enclosures. Enclosure walls may have 

32 openings or vents. That is, for practical applications, electrical enclosures must have at 

33 least three metal walls and a solid top cover. 

34 

35 o The enclosure walls may have openings or vents. Since the FDS simulations 

36 were conducted with enclosures with “no walls” (i.e., only a cabinet top), with two 

37 side walls, and with three walls to ensure the fire is not oxygen limited, this 

38 recommendation ensures a conservative application of the approach even if the 

39 enclosure walls have openings or vents. 

40 

41 o Since FDS has the inherent capability to predict plume temperatures under the 

42 influence of an obstruction, FDS results should never be adjusted in post43 processing calculations to account for the obstructed plume credit. The bias 

44 correction developed in this report does not apply to results obtained directly 
CORRECTION FOR ZONE OF INFLUENCE DUE TO OBSTRUCTED PLUME EFFECT

5-4 

1 from FDS and is only intended for use with the Heskestad fire plume temperature 

2 correlation. A qualified user of FDS should develop an appropriate set of inputs 

3 to address the effects of cabinet obstructions directly, and not by adjusting the 

4 output data with a bias correction. 

5 

6 o The simulations developed in FDS consist of enclosure obstructions with steel 

7 thermo-physical properties consistent with electrical enclosure tops found in NPP 

8 applications. Information is limited to metal or other similarly robust obstructions 

9 that could not fail (melt or burn away) at elevated temperatures and allow 

10 unobstructed plume flows. Note that the results show that the effect of the 

11 obstruction is not strongly sensitive to small openings in the top surface, up to 

12 5% of the top surface area as indicated in Section 5.3.7.2. Therefore, small 

13 openings (≤ 5% of top plate) that may be generated by the heat from the fire due 

14 to warping or tearing of weld joints, etc. can be ignored provided the material is 

15 sufficient to withstand melting or burn away when directly exposed to flames. 

16 The analysis also shows that the result is not strongly sensitive to varying the 

17 thickness of the enclosure surface material in Section 5.3.7.5. Therefore, the 

18 recommendations can be applied to any electrical enclosure provided the above 

19 limitations are also met. 

20 

21  Temperature predictions at specified intervals are made up to 6 m (20 ft.) above the fire 

22 source, which is the typical elevation of room heights in NPPs. The analysis is based on 

23 the highest temperature predicted in the particular plane elevation. 

24 

25  Heat release rates (HRR) up to a limit of 1000 kW, which is roughly equal to the highest 

98th 26 percentile HRR value provided for ignition sources in Tables 4.1 and 4.2 of this 

report. This limit also corresponds to the maximum HRR specified for a 98th 27 percentile 

28 electrical enclosure fire in NUREG/CR-6850. 

29 

30  The current investigation does not consider the effects on the plume temperature after 

31 fire spread to secondary combustibles, such as cable trays or exposed cables ignited 

32 above the initiating fire source. 

33 

34  The current investigation does not consider the potential effects of a fire located adjacent 

35 to a wall or corner; however, there is no evidence to suggest that this analysis will 

36 invalidate the current treatment of these configurations. Existing information on the 

37 treatment of wall and corner effects on the plume ZOI may be applied. 

38 

39  The current investigation applies to defining the thermal plume exposure and extent of 

40 the ZOI, assuming relevant temperature exposures for thermoplastic (TP) and thermoset 

41 (TS) cable targets. The range of relevant temperatures includes 130 °C (266 °F) to 800 

42 °C (1470 °F) as defined in Section 5.3.6. 

43 5.2 Technical Approach 

44 The Heskestad plume correlation is typically used for unobstructed plume simulations and 

45 modified to account for changes in plume temperature due to an obstruction. This modification 

46 is estimated through a comparison of the results of fire model simulations against the existing 

47 Heskestad plume correlation. The software used to simulate and estimate fire plume 

48 temperatures subject to obstructions in this study is FDS Version 6.0.1. 

49 
CORRELATION OF OBSTRUCTED PLUME MODELS WITH HESKESTAD PLUME 

PREDICTIONS 

5-5 

1 FDS is a computational fluid dynamics (CFD) tool, developed and maintained by the National 

2 Institute of Standards and Technology, capable of studying fundamental fire dynamics and 

3 combustion [30], including low speed transport of heat and combustion products from a fire. 

4 FDS solves numerically a form of the Navier-Stokes equations (i.e., conservation of momentum 

5 in fluid flow) appropriate for low speed, thermally driven flow with an emphasis on smoke and 

6 heat transport from fires. The formulation of the equations and the numerical algorithm are 

7 contained in the FDS Technical Reference Guide [31]. Verification and validation of the model 

8 are discussed in the FDS Verification and Validation Guides [32, 33]. FDS has also been 

9 verified and validated for commercial nuclear applications [21]. 

10 5.2.1 Review of Past Studies 

11 A review of the literature was conducted to identify existing studies related to obstructed 

12 plumes. Most studies including fire plume flows subject to an obstruction focus on one of two 

13 areas: (1) exposure to objects of varying sizes and geometries in a fire plume, and (2) delayed 

14 actuation and impeding discharge patterns of sprinklers caused by obstructions. However, no 

15 specific study associated with fire plume temperatures above obstructions was noted. 

16 Information on the impact of obstructions on plume temperatures is needed in the nuclear power 

17 industry as more realism is factored into the modeling of electrical enclosure fires. Fires ignite 

18 inside electrical enclosures, and it may be overly conservative to model the plume without any 

19 consideration of the effects that the top of the enclosure may have on the plume temperature 

20 and hence, on the vertical ZOI. 

21 5.2.2 Plume Theory 

22 The point source solution of turbulent plume flow has shown a remarkable ability to correlate 

23 velocities, temperatures, and mass flow rates above the flame tip [23, 28, 34]. This solution 

24 assumes the fire to be a single point source of heat located near the base of the fire. The 

25 details of the point source become less observable as the distance from the point increase until 

26 only the total heat output of the fire becomes relevant. This investigation focuses on the near 

27 field plume behavior, where the temperatures of interest are comparable to the damage 

28 thresholds of electrical cables used in NPPs. 

29 5.2.2.1 Plume Scaling 

30 Significant efforts have been undertaken in the study of plume theory. Relations developed by 

31 Zukoski [29] are capable of estimating plume temperatures and velocities for fires uninfluenced 

32 by obstructions. Using these relationships, the following simplified proportionality allows for an 

33 estimation of the plume centerline temperatures at different elevations above a fire source by 

34 Beyler [28] 

∆ܶ௠~ܳሶ

ଶ/ଷݖିହ/ଷ 35 (5-1) 

Where, ∆Tm is the rise in plume temperature above ambient in Kelvin, ܳሶ 36 is the heat release rate 

37 in kW, and z is the height above the fire source in meters. Constants of proportionality have 

38 been determined by a number of investigators. The constant of proportionality, A, modified to 

39 include the virtual origin, z0, can be estimated as: 

40 

೘்∆ ൎ ܣ

ொሶమ/యሺ௭ି௭బሻషఱ/య 41 (5-2) 
CORRECTION FOR ZONE OF INFLUENCE DUE TO OBSTRUCTED PLUME EFFECT

5-6 

1 When comparing these constants of proportionality determined by various investigators, values 

2 range from 21.6 to 29.7. A value of 26 is suggested for use when the convective heat release 

3 rate is known and 22 when flame radiation is significant. One of the relations that follow the 

4 above proportionality is the Heskestad fire plume correlation. 

5 5.2.2.2 Heskestad Plume Temperature 

6 In this investigation the correlation used to predict the changing fire plume temperature was 

7 developed by Heskestad: 

∆ܶ ൌ 9.1 ൤ ்బ

൫௚௖೛

మఘబ

మ൯

൨

ଵ

ଷൗ

ܳሶ

௖

ଶ

ଷൗ ሺݖെݖ଴ሻ

ିହ

ଷൗ 8 (5-3) 

9 Where, ∆T is the change in temperature above ambient, g is the acceleration due to gravity, cp

is the specific heat of air, ρ is the density of air, ܳሶ

௖ 10 is the convective heat release rate, z is the 

11 height above the top of the combustible, and z0 is the height of the virtual origin calculated as: 

ݖ ଴ൌ െ1.02ܦ ൅ 0.083ܳሶ

ଶ

ହൗ 12 (5-4) 

13 

Where, D is the diameter of the fire source (m) and ܳሶ 14 is the heat release rate (kW). 

15 This correlation is only valid above the mean flame height, L. The mean flame height can be 

16 calculated as: 

ܮ ൌ െ1.02ܦ ൅ 0.230ܳሶ

ଶ

ହൗ 17 (5-5) 

18 

19 The Heskestad fire plume correlation is chosen for this study because it is identified as the 

20 preferred correlation for use in calculating the damage temperature in ZOI applications by 

21 NUREG/CR-6850 (Appendix F). In addition, the correlation is currently verified and validated for 

22 use in fire PRA [21]. 

23 

24 To determine the effects on plume temperature rise caused by an obstruction on targets above 

25 the obstruction, a modification of the Heskestad fire plume correlation is made to account for 

26 changes in the fire plume temperature rise as given below: 

27 

∆ܶ ൌ ܤ ቆ9.1 ൤ ்బ

൫௚௖೛

మఘబ

మ൯

൨

ଵ

ଷൗ

ቇ ܳሶ

௖

ଶ

ଷൗ ሺݖെݖ଴ሻ

ିହ

ଷൗ 28 (5-6) 

29 

30 Where, B is a bias determined from differences between the plume temperature rise above a 

31 fire subject to an obstruction and those of the unmodified Heskestad fire plume correlation. 

32 5.2.3 The FDS Simulation Parameters 

33 Using FDS, one hundred fifty six (156) simulations, thirty nine (39) unobstructed and one 

34 hundred seventeen (117) with obstructions, were performed to develop the simulated plume 

35 temperature data for this study. Four influencing factors have been chosen to define a “test 

36 matrix,” namely, heat release rate, fire diameter, elevation of the fire source, and number of 

37 enclosure walls included with the obstruction. These factors are based on the study of fire 

38 plume flows currently available in the fire protection engineering literature and the specific 

39 needs for this study. 
CORRELATION OF OBSTRUCTED PLUME MODELS WITH HESKESTAD PLUME 

PREDICTIONS 

5-7 

1 5.2.3.1 Heat Release Rate (HRR) 

2 The HRR is perhaps the most important influencing factor in all fire modeling applications. In the 

3 specific case of axisymmetric fire plumes, it represents the energy released at a point in space 

4 near the base of fire generating the upward movement of flows. Heat release rate values 

5 selected for this study range from approximately 50 to 1000 kW (which is approximately the 

6 highest fire intensity) applied for electrical enclosure heat release rate scenarios. 

7 5.2.3.2 Fire Source Diameter 

8 The fire source diameter characterizes the size of the fire base. It has been identified as an 

9 important parameter governing fire plume temperatures, because it has a strong influence on 

10 plume velocities, entrainment, and flame heights. Consequently, it is included as an influencing 

11 factor to evaluate its impact on fire plume temperatures subject to obstructions. The range of 

12 fire diameters selected for this study are 0.3 m (1 ft.), 0.6 m (2 ft.), 0.9 m (3 ft.), and 1.2 (4 ft.). 

13 The Fire Froude Number (Q*) is used to select pairings of fire diameters and HRRs appropriate 

14 for this investigation. Q* values ranging between 0.34 and 1.87 were calculated for the 

15 parameters used in this study. These values fall mostly within the validated range, 0.4 to 2.4, of 

16 the Q* as reported in Table 2-5 in Volume 1 of NUREG-1824 [21], with a small set of 

17 configurations less than the minimum valid Fire Froude Number of 0.4. These configurations 

18 are not anticipated to invalidate the conclusions generated in this study because the substantial 

19 validation performed for FDS [33] exceeds the limits reported in NUREG-1824 [21], and the 

20 model inputs are prescribed within the existing validation range for use of the FDS. 

21 5.2.3.3 Obstruction Configuration 

22 Electrical enclosures represent a common ignition source in nuclear power plant fire scenarios. 

23 When developing a zone of influence, the fire within an enclosure may be subject to the 

24 enclosure top and sides as an obstruction within the plume region. The obstructions used in 

25 this investigation consist of a flat plate obstruction with a thickness of 0.0015 m (0.06 in) 

26 centered over the fire source at an elevation of 2.3 m (7.5 ft) with a varying number of walls. 

27 The dimensions of the obstructions are 8 cm (3 in) larger than the fire base on a side, and 

28 change in size with the fire source used in each simulation. Obstructions representing electrical 

29 enclosures with no walls and a top cover, two walls with a top cover, and three walls with a top 

30 cover are used in this investigation. 

31 

32 Three different obstructions used in the investigation are shown in Figure 5-1. The first type of 

33 obstruction is a single flat plate obstruction (circled in red). The second obstruction includes the 

34 flat plate and two walls (identified by red arrows) running from the floor surface to the flat plate 

35 obstruction, resembling an arch. The other two surfaces are open to the environment (signified 

36 by the blue line). The third obstruction is similar to the arch obstruction with an additional, third 

37 wall that allows smoke and heat to exit only on the side indicated by the blue arrow. 

38 
CORRECTION FOR ZONE OF INFLUENCE DUE TO OBSTRUCTED PLUME EFFECT

5-8 

1 

2 Figure 5-1 

3 Obstruction Geometries: Flat Plate, Arch, Three Walls 

4 

5 In Figure 5-2, the change in elevation of the fuel source is presented. The three elevations used 

6 in this investigation are 0.3 m (1 ft) – one foot above the floor surface, 1.1 m (3.6 ft) – half the 

7 distance between the floor surface and the top of the obstruction, and 2 m (6.6 ft) – one foot 

8 below the top of the obstruction. 

9 

10 

11 Figure 5-2 

12 Simulation Fire Source Elevations: 0.3048 m, 1.143 m, 1.9812 m 

13 Evidence gathered from these simulations is used to determine the effect of an obstruction on 

14 plume temperatures and subsequently determine any resulting change in the ZOI. 

15 5.2.3.4 Enclosure Configurations 

16 Figure 5-3 illustrates three enclosure configurations seen in NPPs where the obstructed plume 

17 effects are realized. Without considering the wall effect, the enclosure presented in Figure 5-3a 

18 is an example of the single flat plate obstruction geometry. The enclosure is vented on all four 

19 sides with a solid top (circled in red). The enclosure presented in Figure 5-3b has a solid top 

20 and two side walls, resembling arch obstruction geometry (circled in red). The remaining two 

21 top sides are vented to the environment. The enclosure presented in Figure 5-3c is an example 

22 of the three-wall obstruction geometry. The enclosure has three solid walls, a solid top, and a 

23 single door with slotted vents (circled in red). 

24 
CORRELATION OF OBSTRUCTED PLUME MODELS WITH HESKESTAD PLUME 

PREDICTIONS 

5-9 

1 

2 

3 Figure 5-3 

4 Obstruction Configurations: Flat Plate, Arch, and Three Walls 

5 5.2.3.5 FDS Simulation Matrix 

6 A matrix of simulations performed in this investigation is presented in Table 5-1. Each case 

7 study included three obstructed cases and one unobstructed case. In Table 5-1, the different 

8 pairings of HRR, source diameter, and elevation used in this investigation are presented. 

9 Pairings of HRR and source diameter are selected using Q* as identified in Section 5.2.3.2. 

10 Each of the groupings presented in Table 5-1 is used for a simulation with each of the three 

11 obstruction geometries described in Sections 5.2.4.2 to 5.2.4.4. Additionally, a baseline, 

12 unobstructed, geometry is simulated to obtain plume temperatures to be compared with those 

13 measured in the obstructed simulations. 

14 

15 Table 5-1 

16 FDS Obstructed Plume Simulation Test Matrix 

HRR (kW) 

Fire Source Diameter (m) Fire Source Elevation (m) 

0.3 0.6 0.9 1.2 0.3 1.1 2 

50 X N/A N/A N/A X X X 

100 X N/A N/A N/A X X X 

200 N/A X N/A N/A X X X 

300 N/A X X N/A X X X 

400 N/A X X N/A X X X 

500 N/A X X N/A X X X 

600 N/A X X N/A X X X 

1,000 N/A N/A X X X X X 

17 N/A signifies no FDS simulation was performed. 

18 

19 Note that most of the obstructions modeled in this investigation include top obstructions without 

20 any openings or penetrations. In addition, a number of sensitivity simulations were completed 

a) b) c) 
CORRECTION FOR ZONE OF INFLUENCE DUE TO OBSTRUCTED PLUME EFFECT

5-10 

1 using openings of various percentages of the obstruction top surface area. These additional 

2 simulations are used to determine the applicability of information presented in this study when 

3 applied to enclosures with openings or penetrations on the enclosure’s top. 

4 5.2.3.6 Simulation Compartment 

5 The compartment (i.e., the computational space) for the simulations used in this investigation 

6 measures 5 m (16 ft) x 5 m (16 ft) x 6 m (19.7 ft) (see Figure 5-4). The compartment is open on 

7 all sides and includes a concrete floor. In this investigation room heat up effects are not 

8 included. A mesh of 125 x 125 x 150 was used for each simulation, resulting in a grid resolution 

9 of 4 cm [ݔߜ) m)]. 

10 

11 For simulations involving buoyant plumes, a measure of how well the flow field is resolved is 

given by the non-dimensional expression	ܦ∗/ݔߜ, where ܦ ∗12) m) is a characteristic fire diameter: 

ܦ ∗ൌ ൬ ொሶ

ఘబ௖೛்బ√௚

൰

మ

ఱ

13 (5-7) 

14 

All other terms have been defined for Equation 5-7. The values of ܦ ∗15 /ݔߜ defined in this 

investigation range from 7.3 to 19.6, which falls within or exceeds the values of ܦ ∗16 /ݔߜ used in 

17 the validation study of FDS [21]. A larger ratio means more fire dynamics are resolved directly 

18 by FDS and the results are considered more accurate. 

19 

20 Figure 5-4 

21 Simulation Compartment 

22 5.2.3.7 Temperature Measurement Plane 

23 Temperature predictions are obtained using slice files in FDS every 0.03 seconds. Slice files 

24 save horizontal planar slices of data at user specified locations (see Figure 5-5). This is the 

25 equivalent of experimentally placing thermocouple devices at 4 cm (1.6 in) spacing in the 

26 horizontal plane at each elevation. Temperatures used in this investigation are averaged over a 

27 period of 10 seconds in order to determine averaged plume centerline data in a manner similar 

28 to that used to develop the plume correlations by Heskestad. Each simulation predicts a total 

29 time of 30 seconds which, as discussed in Section 5.2.4.1, is longer than necessary to achieve 

30 steady state plume conditions. The slice files are included at elevations spaced every 0.3 m 

31 (1 ft) from the floor to the top of the 6 m tall compartment. Using the slice file to record 
CORRELATION OF OBSTRUCTED PLUME MODELS WITH HESKESTAD PLUME 

PREDICTIONS 

5-11 

1 temperature measurements ensures that the maximum plume temperature can be recorded for 

2 analysis, regardless of its location within the compartment. This is especially important as 

3 different obstruction geometries shift the plumes location away from the center of the fire source 

4 (see Figure 5-5). The maximum plume temperature at elevations above the obstruction is used 

5 to determine the effect of an obstruction on plume temperatures and develop information for any 

6 resulting change in the ZOI. 

7 

8 Figure 5-5 

9 Slice File FDS Simulation Temperature Measurements 

10 5.2.4 Preliminary FDS Simulations 

11 In this section, the results for simulations with fuel sources under different obstruction 

12 configurations are reviewed and analyzed to ensure proper implementation of the analysis and 

13 to confirm that the results provide the correct data. First, the results for unobstructed fires are 

14 discussed for 200 kW and 1000 kW fires. This is then followed by six simulations consisting of 

15 200 kW and 1000 kW fires subject to the three different obstruction configurations. 

16 5.2.4.1 No Obstruction – Baseline 

17 Simulations with the fire source subject to no obstructions for each of eight HRRs, three 

18 diameters, and three fire source elevations used in this investigation were performed for 

19 comparison against the obstructed cases. In Figure 5-6, unobstructed fires with HRRs of 

20 200 kW and 1000 kW are presented. Also shown in Figure 5-6 are two of the fire source 

21 diameters and elevations used in the investigation. The 200 kW fire has an effective fire source 

22 diameter of 0.6 m (1 ft) and a source elevation of 1.1 m (3.6 ft). The 1000 kW fire has an 

23 effective fire source diameter of 0.9 m (3 ft) and a fire source elevation of 2 m (6.6 ft). 

24 

25 
CORRECTION FOR ZONE OF INFLUENCE DUE TO OBSTRUCTED PLUME EFFECT

5-12 

1 

2 

3 Figure 5-6 

4 a) 200 kW, 0.6 m (diameter), 1.1 m (elevation) and b) 1000 kW, 0.9 m (diameter), 2 m 

5 (elevation) – Non-Obstructed Geometry 

6 

7 Figure 5-7 and Figure 5-8 show the HRR versus time for the two unobstructed simulations 

8 presented in Figure 5-6. The HRRs shown are the FDS default described by: 

9 

ܳሶ

ሺݐሻ ൌ	ܳሶ

ቀ௧ ݄ܽ݊ݐ ∙ ଴

ఛ

10 ቁ (5-8) 

Where, ܳሶ 11 ଴ is the user-specified HRR in kW, t is elapsed time in seconds, and ߬ is the time for 

12 the HRR to ramp up to its prescribed value in seconds. The default value for ߬ in FDS, one 

13 second, was specified in this investigation. This fire growth rate is considerably faster than that 

14 provided by NUREG/CR-6850, and is applied here to achieve a fast steady state performance 

15 and limit simulation time. For this study, only the steady state behavior of the plume is of 

16 interest. The HRR for the two simulations quickly reaches the user-specified values of 200 kW 

17 and 1000 kW and varies throughout the remainder of the simulation due to turbulent fluctuations 

18 simulated by FDS. In Figure 5-7 and Figure 5-8, the one-second time-averaged HRR is 

19 presented along with the resulting HRR described by Equation 5-8 directly to verify that the 

20 HRR has been implemented correctly. 

21 

22 In Figure 5-9, the fire plume temperatures predicted by FDS and the Heskestad fire plume 

23 correlation (Equation 5-3) are presented. For the 200 kW and 1000 kW fires, the Heskestad fire 

24 plume correlation agrees with the FDS simulated plume temperatures. Note that the FDS and 

25 Heskestad predictions are essentially the same with only minor variations. The most significant 

26 variation is that for the larger fire, FDS predicts somewhat lower temperatures in the flame zone 

27 region very close to the fire source. This is of no major significance to this study because the 

28 predicted temperatures for both models are in the 700-900 °C range, which is well in excess of 

29 values of interest to fire PRA (e.g., typical cable or component failure temperatures). 

30 

31 
CORRELATION OF OBSTRUCTED PLUME MODELS WITH HESKESTAD PLUME 

PREDICTIONS 

5-13 

1 

2 

3 Figure 5-7 

4 HRR vs. Time, Unobstructed Simulation – 200 kW, 0.6 m (diameter), 1.1 m (elevation) 

5 

6 

7 

8 

9 

10 

11 Figure 5-8 

12 HRR vs. Time, Unobstructed Simulation – 1000 kW, 0.9 m (diameter), 2 m (elevation) 

13 

0

50

100

150

200

250

300

0 5 10 15 20 25 30

HRR (kW)

Time (s)

200 kW 200 kW (Time averaged, 1 sec) FDS Q(t)

0

200

400

600

800

1000

1200

1400

1600

1800

0 5 10 15 20 25 30

HRR (kW)

Time (s)

1000 kW 1000 kW (Time averaged, 1 sec) FDS Q(t)
CORRECTION FOR ZONE OF INFLUENCE DUE TO OBSTRUCTED PLUME EFFECT

5-14 

1 

2 

3 

4 Figure 5-9 

5 Temperature vs. Elevation Above Floor, Unobstructed Simulation – 200 kW, 0.6 m 

6 (diameter), 1.1 m ( elevation) and 1000 kW, 0.9 m (diameter), 2 m (elevation) 

7 5.2.4.2 Flat Plate Obstruction 

8 

9 Figure 5-10 shows fires with HRRs of 200 kW and 1000 kW subject to a flat plate obstruction. 

10 The HRRs for the simulations presented in Figure 5-10 are similar to those presented in Figure 

11 5-7 and Figure 5-8. 

12 

13 

14 

15 Figure 5-10 

16 a) 200 kW, 0.6 m (diameter), 1.1 m (elevation) and b) 1000 kW, 1.2 m (diameter), 2 m 

17 (elevation) – Plate Obstruction 

0

100

200

300

400

500

600

700

800

900

0123456

Temperature (C)

Elevation (m)

200 kW ‐ FDS 200 kW ‐ Heskestad

1000 kW ‐ FDS 1000 kW ‐ Heskestad
CORRELATION OF OBSTRUCTED PLUME MODELS WITH HESKESTAD PLUME 

PREDICTIONS 

5-15 

1 Figure 5-11 presents the temperature at different elevations versus time for the flat plate 

2 obstruction simulation with a 200 kW fire. These results show that the temperature becomes 

3 sufficiently steady after 15 seconds, and within the 30 second duration of the simulations used 

4 in this investigation. Several sensitivity cases were completed using both extended simulation 

5 times and the FDS input parameter ‘TIME_SHRINK_FACTOR,’ which reduces the specific 

6 heats of various materials by a user specified factor. These results, supported by the global 

7 energy balance provided with each simulation, show that the transient heating of the top surface 

8 of the enclosure plays no role in the long term trend of the simulated plume temperatures. 

9 

10 

11 

12 Figure 5-11 

13 Temperature vs. Time, Flat Plate – 200 kW, 0.6 m (diameter), 2 m (elevation) – Elevations 

14 Above the Obstruction 

15 Figure 5-12 presents the temperature profiles for the 200 kW and 1000 kW HRRs subject to a 

16 flat plate obstruction. Also included is the Heskestad (Equation 5-3) fire plume correlation 

17 temperature with identical model inputs. A comparison between the results suggests that the 

18 Heskestad plume temperature equation is over-predicting the plume temperature fires 

19 obstructed by a flat plate. This over-prediction suggests that the flat plate obstruction has 

20 reduced the plume temperature rise at elevations above the obstruction. It is likely that as the 

21 plume flows around the obstruction it is slightly broken up and results in an increased 

22 entrainment of fresh cool air. This entrainment reduces the plume temperature when compared 

23 to an unobstructed case predicted by the Heskestad fire plume correlation. 

24 

25 

0

50

100

150

200

250

300

350

0 50 100 150 200 250 300

Temperature (C)

Time (s)

Ht=2.4 Ht=2.7 Ht=3 Ht=3.3 Ht=3.6 Ht=3.9 Ht=4.2

Ht=4.5 Ht=4.8 Ht=5.1 Ht=5.4 Ht=5.7 Ht=6
CORRECTION FOR ZONE OF INFLUENCE DUE TO OBSTRUCTED PLUME EFFECT

5-16 

1 

2 Figure 5-12 

3 Temperature vs. Elevation Above Floor, Flat Plate Obstruction – 200 kW, 0.6 m 

4 (diameter), 1.1 m ( elevation) and 1000 kW, 1.2 m (diameter), 2 m (elevation) 

5 5.2.4.3 Arch Obstruction 

6 

7 Figure 5-13 shows simulations of a 200 kW fire and a 1000 kW fire subject to an arch 

8 obstruction, a flat plate ceiling located at an elevation of 2.3 m, and two walls. Plots of the HRR 

9 vs. Time for the 200 kW and 1000 kW fires are similar to those seen in Figure 5-7 and Figure 

10 5-8. 

11 

12 

13 

14 Figure 5-13 

15 a) 200 kW, 0.6 m (diameter), 1.1 m (elevation) and b) 1000 kW, 1.2 m (diameter), 2 m 

16 (elevation) – Arch Obstruction 

0

100

200

300

400

500

600

700

800

900

0123456

Temperature (C)

Elevation (m)

200 kW ‐ FDS, Flat Plate 200 kW ‐ Heskestad

1000 kW ‐ FDS, Flat Plate 1000 kW ‐ Heskestad
CORRELATION OF OBSTRUCTED PLUME MODELS WITH HESKESTAD PLUME 

PREDICTIONS 

5-17 

1 The temperature profiles for the 200 kW and 1000 kW simulation are presented in Figure 5-14. 

2 

3 

4 

5 Figure 5-14 

6 Temperature vs. Height Above Floor – Arch Obstruction – 200 kW, 0.6 m (diameter), 1.1 m 

7 (elevation) and 1000 kW, 1.2 m (diameter), 2 m (elevation) 

8 Figure 5-14 includes the Heskestad correlation plume temperatures using identical inputs. It 

9 appears that the arch obstruction is also influential on the plume temperatures, as the simulated 

10 temperatures are lower than those predicted by the Heskestad fire plume correlation. This is 

11 likely a result of the increased entrainment resulting from the two plumes created by the arch 

12 obstruction geometry (see Figure 5-13). Being split into two separate plumes increases the 

13 surface area available for the plumes to entrain cooler fresh air which results in lower plume 

14 temperatures above the obstruction. 

15 5.2.4.4 Three-Wall Obstruction 

16 Figure 5-15 shows simulations of a 200 kW fire and a 1000 kW fire subject to a three-wall 

17 obstruction, a flat plate ceiling located at an elevation of 2.3 m (7.5 ft) and three walls. Plots of 

18 the HRR vs. Time for the 200 kW and 1000 kW fires are similar to those seen in Figure 5-7 and 

19 Figure 5-8. 

20 

21 The temperature profiles for the 200 kW and 1000 kW fires are presented in Figure 5-16. 

22 

23 

24 

25 

0

100

200

300

400

500

600

700

800

900

0123456

TEmperature (C)

Elevation (m)

200 kW ‐ FDS, Arch 200 kW ‐ Heskestad

1000 kW ‐ FDS, Arch 1000 kW ‐ Heskestad
CORRECTION FOR ZONE OF INFLUENCE DUE TO OBSTRUCTED PLUME EFFECT

5-18 

1 

2 

3 Figure 5-15 

4 a) 200 kW, 0.6096 m (diameter), 1.1 m (elevation) and b) 1000 kW, 1.2 m (diameter), 2 m 

5 (elevation) – Three-Wall Obstruction 

6 

7 

8 

9 Figure 5-16 

10 Temperature vs. Height Above Floor – Three-Wall Obstruction – 200 kW, 0.6 m (diameter), 

11 1.1 m (elevation) and 1000 kW, 1.2 m (diameter), 2 m (elevation) 

12 Figure 5-16 includes the Heskestad correlation plume temperatures using identical inputs. It 

13 appears that the three-wall obstruction, similar to the flat plate and arch obstruction, influences 

14 plume temperatures, as the simulated temperatures are lower than those predicted by the 

15 Heskestad fire plume correlation. Once again, this is likely a result of an increased entrainment 

16 of fresh, cool, air in the plume caused by the obstruction. 

0

100

200

300

400

500

600

700

800

900

0123456

Temperature (C)

Elevation (m)

200 kW ‐ FDS, Three Wall 200 kW ‐ Heskestad

1000 kW ‐ FDS, Three Wall 1000 kW ‐ Heskestad
CORRELATION OF OBSTRUCTED PLUME MODELS WITH HESKESTAD PLUME 

PREDICTIONS 

5-19 

1 5.2.4.5 Statistical Analysis 

2 The bias introduced by the plume obstructions is evaluated using the statistical model provided 

3 in NUREG-1934 [18]. In this study, the ‘Experimental’ value (E) may be either the unobstructed 

4 FDS prediction, or the unbiased Heskestad plume from Equation 5-3 [34]. The ‘Modeled’ value 

5 (M) will be the obstructed FDS prediction. This way, the experiment value is based on an 

6 established method to predict plume temperatures that is accepted when used within valid limits 

7 established by NUREG-1824 [21]. The model value is then the new information developed in 

8 this study that is biased by the presence of the obstruction. The following expressions are used 

9 to define the statistical analysis: 

10 

ாߪ ,ߠሺܰ~ߠ|ܧ

ଶ 11 ሻ;		ߪ෤ா ൌ ߪா/ߠ) 5-9 (

12 

ெߪ ,ߠߜሺܰ~ߠ|ܯ

ଶ 13 ሻ;		ߪ෤ெ ൌ ߪெ/ߠߜ) 5-10 (

14 

ln ቀெ

ாቁ തതതതതതതത ൌ ଵ௡ ∑ ln ቀெ೔

ா೔

ቁ ௡

௜ୀଵ 15 (5-11) 

16 

ெ෤ߪ

ଶ ൅ ߪ෤ாଶ ൌ ଵ

ଵି௡ ∑ ቂln ቀெ೔

ா೔

ቁ െ ln ቀெ

ாቁ തതതതതതതത

ቃ

ଶ

௡

௜ୀଵ 17 (5-12) 

18 

ߜ ൌ exp ቀln ቀெ

ாቁ തതതതതതതത ൅ ఙ෥ಾ

మ

ଶ െ ఙ෥ಶ

మ

ଶ

19 ቁ (5-13) 

Where, ܰሺߤ, ߪଶ 20 ሻ indicates a normal distribution with mean,	ߤ, and standard deviation, ߪ, and the 

21 quantities ߠ, ܧ, and ܯ are the True, Experimental, and Modeled quantities of interest. In this 

22 case, ܧ and ܯ are defined as the plume temperature rise above ambient. The relative standard 

23 deviations, ߪ෤ா and ߪ෤ெ, are necessary in this framework and represent the fraction of the 

24 measured quantity that can be attributed to uncertainty. The quantity ߪ෤ா is considered an input 

25 to the statistical model and can be estimated from prior analysis. The model bias, ߜ, is the 

26 primary quantity of interest for this study since it is equivalent to the term ܤ proposed in 

27 Equation 5-6. 

28 5.3 FDS Simulation Results 

29 The FDS simulation results for all these cases are reported in Appendix E (Table E-1 for 

30 obstructed plume cases and Table E-2 for the unobstructed plume base case). 

31 

32 In Figure 5-17, the temperature increase results from all FDS simulations with obstructions are 

33 compared to unobstructed simulations with the same fire characteristics. Included in Figure 

34 5-17 are temperature measurements made from directly above the obstructions, up to an 

35 elevation of 6 m (19.7 ft) at 0.3 m (1 ft) intervals. The x-axis is the unobstructed plume 

36 temperature rise. The y-axis is the equivalent obstructed plume temperature rise. 

37 Consequently, if the obstructed and unobstructed measurements are close to each other, all the 

38 points would fit along the diagonal (bold black line). Data points below the diagonal suggest 
CORRECTION FOR ZONE OF INFLUENCE DUE TO OBSTRUCTED PLUME EFFECT

5-20 

1 lower obstructed plume values when compared with the corresponding unobstructed 

2 predictions. 

3 

4 The results in Figure 5-17 show that obstructions do indeed influence plume temperatures. Two 

5 observations can be made. In most cases, it appears the obstruction reduces the plume 

6 temperatures above the obstructions. However, in a few cases the obstructed temperatures are 

7 greater than those of the unobstructed fire. These cases can be identified by relation to the 

8 ‘perfect match line,’ an indication of when the obstructed and unobstructed temperatures are 

9 equal. It is likely that these instances in which the obstructed temperatures are greater than the 

10 unobstructed temperatures are a result of different entrainment behavior caused by the 

11 obstructions. Of the results where the obstructed temperatures are greater than the 

12 unobstructed case, all measurements were taken at an elevation of 3 m (9.8 ft) or lower, within 

13 0.7 m (2.3 ft) of the top obstruction, with flames reaching consistently or intermittently above the 

14 top obstruction. Furthermore, each of the configurations that exceed the match line corresponds 

15 to a fire located 0.3 m (1 ft) above the floor. This result suggests a limit of applicability for fires 

16 that are located near the base of the enclosure, and this configuration is explored in greater 

17 detail below. 

18 

19 

20 

21 Figure 5-17 

22 Unobstructed versus Obstructed Plume Temperatures 

23 5.3.1 Analysis of Non-Conservative Results 

24 In Figure 5-18 screen captures from one the simulations for the red dots near 500 °C (932 °F) 

25 highlighted in Figure 5-17 is shown. The data is from measurements made at an elevation of 

26 2.4 m (7.9 ft), approximately 0.1 m (0.3 ft) above the top obstruction. In both incidents, the 

27 flames can be seen intermittently expanding above the top obstruction. 

28 

29 Results from the simulations presented in Figure 5-18 show the flames intermittently reaching 

30 out and above the ceiling of a three-wall obstruction. The spillover of the flames has an effect of 

31 increasing the 10 second time averaged temperature used in this analysis. The increased flame 

0

200

400

600

800

1000

0 200 400 600 800 1000

∆

TOBST

∆TUNOBST

Data Perfect Match Line

In or near the flames
CORRELATION OF OBSTRUCTED PLUME MODELS WITH HESKESTAD PLUME 

PREDICTIONS 

5-21 

1 heights and resulting increased temperatures are likely a result of reduced entrainment within 

2 the obstruction. However, the remainder of the plume temperatures above the obstruction are 

3 lower than those for an unobstructed case. 

4 

5 

6 

7 Figure 5-18 

8 a) Three-Wall Obstruction, 500 kW, 0.3 m b) No Obstruction, 500 kW, 0.3 m 

9 Another case where two simulations produce data above the perfect match line is examined for 

10 the red region near 900 °C (1652 °F) circled in Figure 5-17. In Figure 5-19, the comparison 

11 between a three-wall obstruction around a fire source at an elevation of 2 m (6.6 ft) and that of 

12 an unobstructed case is presented. Comparing these simulations, the flame length in the 

13 unobstructed simulation is greater than that observed in the obstructed simulation. Since both 

14 cases are within the flame region of the fire source, it is normal that they both produce 

15 temperatures near 900 °C (1652 °F), which is widely reported as the temperature within the 

16 flame by Heskestad. Since temperatures very near and inside the flame do not correlate with 

17 height as indicated in Equation 5-3, temperatures near the flame temperature should be filtered 

18 from the final analysis to determine the bias induced by the obstructions. 

19 

20 

21 
CORRECTION FOR ZONE OF INFLUENCE DUE TO OBSTRUCTED PLUME EFFECT

5-22 

1 Figure 5-19 

2 a) Three-Wall Obstruction, 1000 kW, 1.2192 m b) No Obstruction, 1000 kW, 1.2 m 

3 5.3.2 Obstruction Configuration 

4 The same results presented in Figure 5-17 are presented once again in Figure 5-20; however, 

5 they are now grouped by the configuration of the obstruction used in the simulations. 

6 

7 Grouping the data by obstruction geometry does not point out any significant trends. This 

8 suggests that the geometry of an obstruction is not significant in terms of how the temperature 

9 rise is affected, but that simply the presence of an obstruction is influential. 

10 

11 However, some observations can be made from the results presented in Figure 5-20. It 

12 appears that the plume temperatures from the fires subjected to the three-wall obstruction are 

13 slightly closer to those of the unobstructed case when compared to the arch and flat plate 

14 geometries, which appear to have larger differences on average. The different performances 

15 are not considered to be statistically significant, and the ultimate information does not 

16 distinguish between the three configurations of the obstruction. 

17 

18 

19 Figure 5-20 

20 Unobstructed versus Obstructed Plume Temperatures – Different Geometries 

21 In Figure 5-21, plume flows for the three different obstructions are presented for comparison 

22 with an unobstructed case. A comparison between Figure 5-21a and Figure 5-21d indicates 

23 that the flat plate obstruction has a tendency to increase the plume width at elevations around 

24 and above the obstruction. This causes an increased entrainment of fresh air into the plume 

25 and the observed reduced plume temperatures. 

26 

0

200

400

600

800

1000

0 200 400 600 800 1000

∆

TOBST

∆TUNOBST

Flat Plate Arch Three Wall Perfect Match Line
CORRELATION OF OBSTRUCTED PLUME MODELS WITH HESKESTAD PLUME 

PREDICTIONS 

5-23 

1 

2 

3 Figure 5-21 

4 Plume Flows Subject to Different Obstruction Geometries: a) Flat Plate, b) Arch, c) Three5 Wall, d) Unobstructed 

6 As discussed in the previous section, the arch obstruction, Figure 5-21b, causes the plume to 

7 be split into two separate plumes directly above the obstruction. (It is possible for the two 

8 separate plumes to reconcile at higher elevations as shown in Figure 5-13. This split allows for 

9 an increased surface area with which fresh air can be entrained and the plume temperatures 

10 can be reduced.) 

11 

12 Plumes subject to the three-wall obstruction geometry (Figure 5-21c) are shifted off center when 

13 compared to the unobstructed geometry. Similar to the flows subject to the flat plate 

14 obstruction, the three-wall obstruction appears to increase the plume width around and above 

15 the obstruction. This is likely the cause of the lower plume temperatures above the three-wall 

16 obstruction. In the previous section it was suggested that the three-wall obstruction geometry 

17 limits entrainment of fresh air at elevations below the top of the obstruction and that this 

18 entrainment likely increases the temperatures around and directly above the top. The 

19 competing effects of an increased entrainment from a larger plume area above the obstruction 

20 and the reduced entrainment within the obstruction are likely a reason temperatures above this 

21 obstruction are slightly higher than those of the other obstructions observed. 

22 5.3.3 Fire Source Diameter 

23 In Figure 5-22, the unobstructed and obstructed temperature comparisons are split into groups 

24 based on the different fire source diameters. 

25 

a) b) c) d)
CORRECTION FOR ZONE OF INFLUENCE DUE TO OBSTRUCTED PLUME EFFECT

5-24 

1 

2 

3 Figure 5-22 

4 Unobstructed versus Obstructed Plume Temperatures – Different Fire Source Diameters 

5 This grouping shows that, except at the lower ranges of plume temperature rises, only the larger 

6 diameter fires show instances of obstructed temperature rises greater than the unobstructed 

7 cases. Recalling the test matrix, the larger diameters allow for fires with larger HRRs, given the 

8 ranges on Q* for NPP scenarios [21]. This likely contributes to the limited amount of fires with 

9 diameters of 0.3 m (1 ft) that produce temperatures near the flame temperature. 

10 5.3.4 Heat Release Rate 

11 In Figure 5-23 the unobstructed and obstructed temperature comparisons are split into groups 

12 based on the different heat release rates. 

13 

14 Grouping the comparisons by HRR, similar to the comparison of different obstruction 

15 geometries, no clear trend is seen. There is evidence of lower obstructed plume temperatures 

16 from fires ranging from the lowest HRR used in this investigation of 50 kW to those of the 

17 largest with a HRR of 1000 kW. This shows that the presence of an obstruction and its effect on 

18 the plume temperatures is observable over a range of different HRRs. If any trend can be 

19 gleaned from the results grouped by HRR, it is that the results appear similar to those of the fire 

20 source diameter groupings presented in Figure 5-22 in which smaller fires are grouped at lower 

21 temperature and larger fires are capable of exceeding the unobstructed case in some 

22 configurations. 

23 

24 

0

200

400

600

800

1000

0 200 400 600 800 1000

∆

TOBST

∆TUNOBST

D = 0.3048 m D = 0.6096 m D = 0.9144

D = 1.2192 Perfect Match Line
CORRELATION OF OBSTRUCTED PLUME MODELS WITH HESKESTAD PLUME 

PREDICTIONS 

5-25 

1 

2 

3 Figure 5-23 

4 Unobstructed versus Obstructed Plume Temperatures – Different HRRs 

5 5.3.5 Fire Source Elevation 

6 In Figure 5-24 the simulations used in this investigation are grouped by the elevation of the fire 

7 source. 

8 

9 Grouping the data by fire source elevation brings insights as to the effect of an obstruction on 

10 plumes modeled in electrical enclosures. Following the ‘one-foot rule,’ current information [15] 

11 recommends that if an enclosure is unvented, a fire should be assumed to be located at an 

12 elevation of one foot below the top of the enclosure. In Figure 5-24, it is clear that the fires 

13 located 0.3 m (1 ft.) above the ground demonstrate different behavior than either of the elevated 

14 fuel sources. The average behavior of these cases demonstrates lower temperatures, but the 

15 variability of the case suggests that it is possible that the fire performs similarly to an 

16 unobstructed case. A number of possibilities are considered to account for these observations. 

17 As already discussed, in some cases it is likely the obstruction causes a focusing of the plume 

18 flow when compared to an unobstructed case. It is also possible that in some cases the walls at 

19 the edge of the simulation compartment cause a tilting of the plume flow such that the flow is not 

20 significantly affected by the presence of the obstruction and the natural variation in turbulent 

21 plume flow results in higher temperatures. This suggests that the information proposed in this 

22 investigation should not include fires at elevations less than half the height of the enclosure, as 

23 they behave similarly to fires in unobstructed configurations. 

24 

25 

0

200

400

600

800

1000

0 200 400 600 800 1000

∆

TOBST

∆TUNOBST

50 kW 100 kW 200 kW

300 kW 400 kW 500 kW

600 kW 1000 kW Perfect Match Line
CORRECTION FOR ZONE OF INFLUENCE DUE TO OBSTRUCTED PLUME EFFECT

5-26 

1 

2 

3 Figure 5-24 

4 Unobstructed versus Obstructed Plume Temperatures – Different Fire Source Elevations 

5 Additionally, current information in NUREG/CR-6850, Supplement 1 [15] states that the location 

6 of the fire be based on visual observation of the enclosure internals. However, this can be 

7 challenging if there are numerous cable bundles in different orientations or for cases in which a 

8 visual inspection of the enclosure internals is unavailable. In such cases, current information 

9 stipulates that fires are to be located 0.3 m (1 ft.) below the top of the enclosure, at the 

10 uppermost vent if the enclosure is vented, or at the highest location of any door or opening that 

11 may be expected to fail [15]. Therefore, given the observations that the fires located 0.3 m 

12 (1 ft.) above the ground are less likely to exhibit obstructed plume behavior and in keeping with 

13 current information, the results from simulations for fires located 0.3 m (1 ft.) above the ground 

14 are not included in the further analysis and information provided in this investigation. 

15 5.3.6 Statistical Analysis 

16 The results presented above indicate the necessity to define valid limits on the selection of 

17 temperature data for this analysis for determination of plume ZOI. As discussed above, 

18 temperatures within the flame region have been filtered out of the analysis. Temperatures 

19 within the flame height are typically not necessary in fire PRAs, in favor of more conservative 

20 treatments of damage (i.e., targets within the flame are damaged instantly). Since the 

21 maximum extent of the plume vertical ZOI always contains the flame height region, knowledge 

22 of the flame height is not necessary to develop a conservative treatment in the fire PRA. 

23 Furthermore, correlations such as that developed by Heskestad do not apply for temperatures 

24 very near the flames where near constant temperature rise is observed. This behavior 

25 effectively limits the data used in this analysis to temperatures less than approximately 800 °C 

26 (1472 °F). 

27 

28 Additionally, temperatures below 130 °C (266 °F) are below temperatures that are used for 

29 target damage in NPP applications (i.e., 205 °C (400 °F) and 330 °C (626 °F) for thermoplastic 

30 and thermoset cables, respectively, per NUREG/CR-6850, Table 8-2). This temperature was 

31 chosen because it results in a negligible probability of causing damage for the 205°C (400 °F) 

0

200

400

600

800

1000

0 200 400 600 800 1000

∆

TOBST

∆TUNOBST

1 ft. Above Ground Middle of Cabinet

1ft. Below top of Cabinet Perfect Match Line
CORRELATION OF OBSTRUCTED PLUME MODELS WITH HESKESTAD PLUME 

PREDICTIONS 

5-27 

1 limit using the bias (1.18) and normalized standard deviation (0.20) calculated for FDS [33]. A 

2 simple means of assessing the probability that a given prediction exceeds a threshold value due 

3 to model uncertainty is provided in NUREG-1934/EPRI 1023259 [18]. This probability may be 

4 determined from the following equation: 

ܲሺݔ൐ݔ௖ሻ ൌ ଵ

ଶ

erfc ቀ

௫೎ିఓ

ఙ√ଶ

5 ቁ (5-14) 

6 

Where, ܲ is the probability, ݔ is a parameter value, ݔ ௖7 is a threshold parameter value, ߤ is the 

8 mean ‘true’ predicted value of the parameter, ߪ is the standard deviation of the model prediction 

9 for the parameter of interest, and the complementary error function is denoted by ‘erfc’. The 

10 mean value is determined from the model bias as follows: 

11 

 (5-15) ߜ/ܯ ൌ ߤ 12

13 

14 Where, ܯ is the model prediction and ߜ is the model bias. The standard deviation is computed 

15 from the normalized standard deviation as follows (NUREG-1934, 2012): 

16 

 (5-16) ሻߜ/ܯெሺ෤ߪൌߪ 17

18 

19 Where, ߪ෤ெ is the normalized standard deviation. 

20 

21 The model bias and normalized standard deviation for FDS, Version 6 are as follows [33]: 

22  Plume Temperature (model bias): 1.18 

23  Plume Temperature (normalized standard deviation): 0.20 

24 Following the procedures above, a model temperature prediction of 130 °C (266 °F) would result 

25 in a 0.00006% chance of causing damage to a target with a 205 °C (400 °F) critical 

26 temperature, due to model uncertainty. 

27 5.3.7 Summary of Results 

28 Recall that in the discussion of plume scaling theory in Section 5.2.2.1, a proportionality 

29 constant (ܣ (was defined in Equation 5-2 (shown below again) as characterizing the ratio of 

30 plume temperature rise to a functional group made up of the fire HRR, and the distance from the 

31 fire’s virtual origin: 

32 

೘்∆ ൎ ܣ

ொሶమ/యሺ௭ି௭బሻషఱ/య 33 (5-17) 

34 

35 Further, Beyler [28] noted that the values reported by various investigators ranged from 21.6 to 

36 29.7. Results from this investigation have been used to estimate modified average 

37 proportionality constants for fires subject to an obstruction. The average proportionality 

38 constants for the flat plate, arch, and three-wall obstructions are 16.6, 10.9, and 16.2, 

39 respectively. The fact that these values are lower than those reported for unobstructed plumes 

40 reflects the observation that the obstructions cause lower fire plume temperatures than would 
CORRECTION FOR ZONE OF INFLUENCE DUE TO OBSTRUCTED PLUME EFFECT

5-28 

1 be observed for an unobstructed plume given the same fire HRR and elevation above the fire 

2 source. 

3 

4 The relative magnitude of these three values is also interesting. The lowest value, indicating the 

5 most significant effect relative to reducing plume temperatures, is associated with the arch 

6 configuration. This likely reflects the fact that the arch splits the plume into two parts that may 

7 not re-form over the obstruction, leading to enhanced entrainment as noted earlier. The highest 

8 value, indicating the least significant temperature reducing effect, is associated with the flat 

9 plate. In this case, the plume is disrupted, but re-forms into a single plume directly above the 

10 obstruction. As a result, the impact on temperature is reduced somewhat compared to the other 

11 cases. The three-wall configuration falls between the other two cases. With the three-wall 

12 obstruction a single plume is maintained, but that plume is diverted sharply sideways before 

13 regaining upward momentum. 

14 

15 In Figure 5-25 the temperature rise above an obstruction predicted using the average 

16 proportionality constants for the different obstructions plotted against the elevation ‘z’ (see 

17 Section 5.2.2.1) above the source normalized by the characteristic fire diameter, D*, is 

18 presented. For comparison, the temperature rise predicted using the suggested proportionality 

19 constant of 26 by Beyler is included in Figure 5-25. These predictions are made using a 

20 representative case evaluated in this investigation: a HRR of 600 kW, a fire source diameter of 

21 0.6096 m, an ambient temperature of 20 °C (68 °F), and a radiative fraction of 0.3. 

22 

23 

24 

25 Figure 5-25 

26 Obstruction Effect on Plume Proportionality Constant 

27 The lower temperature rise predictions for the obstructed cases are evidence that the 

28 obstructions are reducing the plume temperatures above an obstruction. Also of note is that the 

29 temperature predictions for the three geometries are very similar, and it is not necessary to 

30 differentiate between them in the information. 

31 

32 Figure 5-25 demonstrates that the observed results for obstructed plumes can dramatically 

33 decrease plume temperatures and reduce the corresponding vertical ZOI for these fires using 

34 this approach. 

0

50

100

150

200

250

300

350

400

450

0 2 4 6 8 10 12

∆

T (C)

z/D*

Average (Beyler) Flat Plate Arch Three Wall
CORRELATION OF OBSTRUCTED PLUME MODELS WITH HESKESTAD PLUME 

PREDICTIONS 

5-29 

1 5.3.7.1 Bias and Uncertainty 

2 For the use of the results presented in this investigation with the Heskestad fire plume 

3 correlation in probabilistic analyses, model bias and uncertainty statistics for the plume 

4 temperature rise are provided in Table 5-2. The statistics provided were determined following 

5 the methods outlined in the FDS user’s guide [30]. Table E-3 in Appendix E presents the FDS 

6 results for this evaluation. 

7 

8 The bias of 0.62 estimated by a comparison of the temperature rise measured above an 

9 obstruction in the simulations to those estimated by the Heskestad fire plume correlation is the 

10 bias to be used when estimating obstructed plume temperatures using Equation 5-6 and the 

11 vertical plume ZOI. Examples of how to apply this bias and determine the change in the plume 

12 temperature rise and the vertical ZOI for a fire subject to an obstruction are presented in 

13 following section. 

14 

15 Table 5-2 

16 Bias and Uncertainty of Obstructed and Unobstructed Plume Temperature Rise 

Comparison Bias Model Uncertainty Experimental Uncertainty [33] 

Obstructed versus Unobstructed 0.54 0.32* 0.20

Unobstructed versus Heskestad 1.17 0.14 0.20

Obstructed versus Heskestad 0.62 0.28* 0.20

17 *Note: Observing the results presented in Figure 5-26 and Figure 5-28, the actual scatter in the 

18 data supports an estimated model uncertainty closer to 20%. 

19 In Figure 5-26, a comparison of the bias and uncertainty results is presented with the obstructed 

20 and unobstructed plume temperature comparison results. This comparison is used to 

21 demonstrate that the two configurations demonstrate different performance and that this 

22 difference is sufficient to warrant enhanced treatment. The bias shows a clear tendency of the 

23 plume temperature rise from a fire subject to an obstruction to be lower than the unobstructed 

24 case by around 46%, which is considered significant. 

25 

26 In Figure 5-27, results from simulations without obstructions are compared with the plume 

27 temperature rise predicted when using the Heskestad fire plume correlation. This comparison is 

28 used to demonstrate that both FDS and the Heskestad fire plume correlation produce similar 

29 results when used to predict identical configurations. The figure shows similarity between the 

30 FDS simulations and the Heskestad fire plume correlation. There is a slight tendency for the 

31 FDS simulated results to be higher than those predicted by the Heskestad fire plume correlation 

32 with a bias of 1.17; however, the difference between the two models is considered to be 

33 acceptable. 

34 

35 
CORRECTION FOR ZONE OF INFLUENCE DUE TO OBSTRUCTED PLUME EFFECT

5-30 

1 

2 

3 Figure 5-26 

4 Unobstructed versus Obstructed Plume Temperatures – Bias and Uncertainty 

5 

6 

7 

8 Figure 5-27 

9 Heskestad versus Unobstructed Plume Temperatures – Bias and Uncertainty 

10 When the plume temperature rise results for the simulations with obstructions are compared 

11 with the Heskestad fire plume correlation a difference is clear. In Figure 5-28, the obstructed 

12 fire plume temperature rise results are compared with the Heskestad fire plume correlation. The 

13 results show a clear estimation of lower temperatures for fires subject to obstructions. This 

14 suggests that in using the Heskestad fire plume correlation without accounting for obstruction 

15 cooling, fire plume temperatures are being over-estimated. The bias estimated when comparing 

‐200

0

200

400

600

800

0 100 200 300 400 500 600 700 800 900

∆

TOBST (C)

∆TUNOBST  (C)

Data Perfect Match Line

Bias Lower Uncertainty

Upper Uncertainty

0

100

200

300

400

500

600

700

800

900

0 100 200 300 400 500 600 700 800 900

∆

TUNOBST (C)

∆THeskestad (C)

Data Perfect Match Line

Bias Lower Uncertainty

Upper Uncertainty
CORRELATION OF OBSTRUCTED PLUME MODELS WITH HESKESTAD PLUME 

PREDICTIONS 

5-31 

1 the obstructed plume temperature rise to those estimated by the Heskestad fire plume 

2 correlation is 0.62. 

3 

4 

5 

6 Figure 5-28. Heskestad versus Obstructed Plume Temperatures – Bias and Uncertainty 

7 Results and evidence gathered from this investigation have potential to influence ZOI damage 

8 applications for NPP scenarios. 

9 5.3.7.2 Sensitivity to Center Openings on the Obstruction 

10 A number of simulations are performed with openings of varying sizes in the top of the 

11 obstruction. The opening is described as single opening in the center of the obstruction, as this 

12 is considered to be a conservative representation of distributed openings or penetrations that 

13 would be characteristic in NPPs. The sizes used in this analysis ranged from 6.5% to 14% of 

14 the total top surface area. The temperature rise above the obstruction using the different 

15 openings was compared to the temperature rise above unobstructed fires. The FDS results for 

16 this evaluation are presented in Table E-4 of Appendix E. 

17 

18 Opening percentages are dependent on the grid size and the source diameter of the 

19 simulations. Openings of sizes around 10% were selected to determine the effect of an opening 

20 on the plume temperatures above an obstruction. Two HRRs, 200 kW and 600 kW, were also 

21 used in these simulations to determine if changes caused by an opening were sensitive to 

22 changes in the HRR. The effect of an opening on the plume temperature above an obstruction 

23 does not appear to be sensitive to changes in the HRR. 

24 

25 The resulting biases presented in Table 5-3 show that openings of around 6.5% result in a fire 

26 plume temperature rise bias of 0.68, which differs from the obstructed bias of 0.54. As the 

27 cabinet open percentage increases to 12-14% of the total cabinet top area, the bias increases to 

28 0.77, which is a noticeable departure from 0.54. These differences are considered sufficient to 

29 warrant an additional limit of applicability. Based on an interpolation of the evidence, a 5% 

30 opening would result in an approximate bias difference of less than 15% when compared to the 

0

100

200

300

400

500

600

700

800

900

0 200 400 600 800

∆

TOBST

∆THeskestad (C)

Data Perfect Match Line Bias

Lower Uncertainty Upper Uncertainty
CORRECTION FOR ZONE OF INFLUENCE DUE TO OBSTRUCTED PLUME EFFECT

5-32 

1 obstructed cases with no openings. In practice, a change in the exposure of less than 15% is 

2 considered insensitive to the parameter variation relative to the uncertainty of the overall fire 

3 PRA. A 15% percent threshold is selected based on the uncertainty in the measurement of the 

4 HRR parameter [35], which reportedly ranges from 17% to 23%. Because the heat release rate 

5 is a primary input and the value is set based on information provided in Chapter 4 of this report, 

6 the output resolution is selected to be consistent with the uncertainty in the input. Therefore, the 

7 information provided in this investigation is applicable for enclosures with openings up to 5% of 

8 the total top surface area. Any enclosure with cumulative openings in the top greater than 5% 

9 should be treated as an unobstructed geometry. An enclosure top may have penetrations, but 

10 as long as those penetrations are properly sealed those penetrations do not contribute to the 

11 cumulative opening area. Properly sealed openings include cable inside steel conduit, cable 

12 trays with solid steel top and bottom covers, and other penetrations with approved non13 combustible wrap materials. Any opening that may allow airflow through the top of the 

14 enclosure should be considered in the 5% cumulative opening fraction, including all 

15 penetrations which cannot be clearly observed as well sealed. 

16 Table 5-3 

17 Bias and Uncertainty of Obstructed (with Center Opening) and Unobstructed Plume 

18 Temperature Rise 

Comparison Bias Model Uncertainty Experimental Uncertainty [33] 

Obstructed versus Unobstructed 0.54 0.32 0.20

Opening (6.5%) versus Unobstructed 0.68 0.14 0.20

Opening (12‐14%) versus Unobstructed 0.77 0.17 0.20

19 5.3.7.3 Sensitivity to Fire Orientation 

20 A number of simulations were performed with fires oriented vertically (See Figure 5-29). In 

21 these simulations the fire source originates at the floor of the simulation compartment and 

22 reaches to an elevation of 1.96 m (6.4 ft), approximately 0.3 m (1 ft.) below the top of the 

23 obstruction. In configuration a), fuel is released on all sides and across the full height of the 

24 column shaped fire source to simulate the effect of distributed combustible materials in the 

25 center of the enclosure. In configuration b), fuel is released on all interior surfaces of the 

26 electrical enclosure to simulate the effect of combustible materials mounted solely to the walls of 

27 the enclosure. The simulations using the vertical fire source are compared to the simulations 

28 with horizontal fire sources at different elevations used to develop the information presented in 

29 this report. Table E-5 of Appendix E presents the FDS results for this sensitivity evaluation. 

30 

31 Comparing the different simulations, the vertical fire source plume temperatures are very similar 

32 to those of a horizontal fire source with an elevation located in the center of the enclosure. 

33 Plume temperatures from simulations using horizontal fire sources located 0.3 m (1 ft.) below 

34 the top of the obstruction are found to be more conservative than those observed in the vertical 

35 fire source simulations. This suggests that assuming a horizontal fire source located 0.3 m 

36 (1 ft.) below the top of the obstruction results in a conservative analysis when compared to 

37 simulating a vertical fire source. 

38 
CORRELATION OF OBSTRUCTED PLUME MODELS WITH HESKESTAD PLUME 

PREDICTIONS 

5-33 

1 

2 Figure 5-29 

3 a) Vertically Oriented Fire Source, b) Fire Source Located Along the Cabinet Wall 

4 Surfaces 

5 The opposite is found when comparing the vertical fire source plume temperatures with a 

6 horizontal fire source located 0.3 m (1 ft.) from the ground. In this comparison, the plume 

7 temperatures from the vertical fire source often exceed those of the horizontal source, resulting 

8 in a non-conservative comparison. As discussed in Section 6.4, the information following this 

9 investigation does not apply to fires located at elevations lower than the mid height of the 

10 enclosure. Therefore, a vertically oriented fire source can be conservatively represented by a 

11 horizontal fire source applied within the limits of implementation, and no additional restrictions 

12 are required. 

13 5.3.7.4 Sensitivity to Obstructions with a Soffit 

14 A number of simulations were performed using top obstructions equipped with a vertical soffit 

15 (see Figure 5-30). In these simulations the soffit is specified to extend 12 cm (6 in) below the 

16 top obstruction. This configuration is intended to simulate the possible effect of the soffit to 

17 change the thermal plume dynamics. Primarily, the soffit has the effect of reducing the 

18 horizontal extent of the plume observed in Figure 5-21 for some configurations. 

19 Comparing the different simulations, the results of the top surface with a soffit are very similar to 

20 those of the flat top surface considered as the basis of this report. Plume temperature 

21 predictions of the soffit sensitivity cases are plotted with the original results in Figure 5-31. The 

22 results of the soffit obstructions fall within the existing scatter of data, or may fall below the 

23 existing data. This indicates that the existing approach for defining the bias and uncertainty will 

24 conservatively bound the effects of the soffit. 

25 
CORRECTION FOR ZONE OF INFLUENCE DUE TO OBSTRUCTED PLUME EFFECT

5-34 

1 

2 Figure 5-30 

3 Top Obstruction with a Soffit 

4 

5 

6 

7 Figure 5-31 

8 Unobstructed vs. Obstructed Plume Temperatures – Soffit Sensitivity 

9 5.3.7.5 Sensitivity to Thickness of Steel Enclosure 

10 A number of simulations were performed using top obstructions with various specified material 

11 thicknesses. The default material thickness used in this study is 0.0015 m, and the sensitivity 

12 cases consider effects of thicknesses of 0.001 m and 0.01 m. These configurations are 

13 intended to simulate the possible effect of the material thickness to alter the plume temperatures 

14 through surface heat transfer effects. 

0

200

400

600

800

1000

0 200 400 600 800 1000

∆

TOBST

∆TUNOBST

Flat Plate Arch Three Wall

Perfect Match Line Flat Plate ‐ Soffit Arch ‐ Soffit

Three Wall ‐ Soffit
CORRELATION OF OBSTRUCTED PLUME MODELS WITH HESKESTAD PLUME 

PREDICTIONS 

5-35 

1 Comparing the different simulations, the results of varying the thickness of the top surface are 

2 very similar to those of the default thickness considered as the basis of this report. Plume 

3 temperature predictions of the sensitivity cases are plotted with the original results in Figure 

4 5-32. The results of the sensitivity cases fall within the existing scatter of data. This indicates 

5 that the existing approach for defining the bias and uncertainty can accurately predict the effects 

6 of various top obstruction thicknesses between 0.001 m and 0.01 m. 

7 

8 

9 Figure 5-32 

10 Unobstructed vs. Obstructed Plume Temperatures – Enclosure Thickness Sensitivity 

11 5.3.8 Horizontal Zone of Influence 

12 A horizontal ZOI may be defined for any ignition source defined in the fire PRA. This zone of 

13 influence is designed to determine the targets that may be damaged by thermal radiation 

14 exposure from the ignition source. While evaluating the obstructed plume temperatures, it was 

15 observed that a substantial horizontal component of the plume shift may occur. This section will 

16 quantify the observed horizontal shift of the obstructed plume, and compare the observed shift 

17 to existing methods of quantifying the extent of the horizontal ZOI. 

18 5.3.8.1 Existing Definition of Horizontal ZOI 

19 There are a number of existing methods to determine the horizontal zone of influence 

20 associated with an electrical enclosure fire. This section will not attempt to define all potential 

21 approaches that are validated for defining the horizontal ZOI, but will focus on the simplest and 

22 most common method in application. The Fire Protection Significance Determination Process 

23 (SDP) [19] defines the ZOI as the “ball and column” approach illustrated in Figure 5-33. Here, 

24 the radius, R, of the ball portion is defined as the critical radial distance that the ignition source 

25 may produce thermal radiation damage to an electrical target (e.g., cables). The height, H, of 

26 the column portion is defined as the critical vertical distance that the ignition source may 

27 produce thermal plume damage to an electrical target. The union of these two damage zones is 

28 typically evaluated as a cylindrical volume with a radius, R, and a height, H, inside which all 

electrical targets will be damaged given the occurrence of a 98th 29 percentile fire size in the 

30 ignition source. 

0

200

400

600

800

1000

0 200 400 600 800 1000

∆

TOBST

∆TUNOBST

Flat Plate Arch Three Wall Perfect Match Line 1 mm 1 cm
CORRECTION FOR ZONE OF INFLUENCE DUE TO OBSTRUCTED PLUME EFFECT

5-36 

1 

2 The height of the cylinder can be defined exactly using Equation 5-3 for the unobstructed plume 

3 or Equation 5-6 for the obstructed plume with the appropriate selection of the model bias. The 

4 radius of the cylinder can be defined in a number of ways, but the simplest is the Point Source 

5 Model (PSM, Equation 5-18) defined in NUREG-1805, Supplement 1. 

6 

ݎ ൌ ට ௑ೝொሶ

ସగ௤ሶ" 7 (5-18)

8 

Where r (m) is the radial distance from the source location, ܺ௥ (-) is the radiative fraction, ܳሶ 9 (kW) 

10 is the HRR, and ݍሶ" (kW/m2) is the radiative damage heat flux. Note that the guidance in 

11 NUREG/CR-6850 Supplement 1 suggests that the source location of the fire for an electrical 

12 enclosure should be treated as the edge of the enclosure to account for burning at the vent. 

13 Tables of the dimensions of the ZOI can be calculated for many different heat release rate and 

14 target thermal property combinations, examples of which are provided in NUREG/CR-6850, 

15 Table F-2 and the Fire Protection SDP, Table 2.3.2. The distance from the center of the 

16 electrical enclosure to the edge of the ZOI is then defined as: 

17 

ܴோ௔ௗ ൌݎ ൅ௐ

ଶ ൌ ට ௑ೝொሶସగ௤ሶ"

൅ ௐ

ଶ

18 (5-19)

19 Where ܴோ௔ௗ is an appropriate metric to compare the horizontal extent of the ZOI produced by 

20 the shifted plume associated with the obstructed plume simulations. 

21 

22 

23 Figure 5-33 

24 SDP Ball and Column 

25 W: The diameter of the ignition source (m) 

26 R: Critical the radial distance (heat flux) (m) 

27 H: Critical distance for plume heights (m) 

28 
CORRELATION OF OBSTRUCTED PLUME MODELS WITH HESKESTAD PLUME 

PREDICTIONS 

5-37 

1 5.3.8.2 Horizontal Plume Shift ZOI 

2 The obstructed plume simulation results demonstrated horizontal shifts of the plume centerline. 

3 This shift has the potential to expand the horizontal zone of influence associated with the 

4 ignition source. This effect is visualized in Figure 5-34, where the arch and three-wall 

5 obstructions produce clear horizontal shifts of the plume. The location of the plume centerline 

6 can be evaluated directly from the FDS slice file results in parallel with the determination of the 

7 peak centerline plume temperature as described in Section 5.2.3.7. This approach is visualized 

8 in Figure 5-35, and the location of the peak plume temperature relative to the center of the 

9 electrical enclosure is defined as ܴ௉ை (m). This metric allows for an immediate comparison of 

10 the plume shift to the thermal radiation ZOI. 

11 

12 Figure 5-34 

13 Obstruction Plume Shift 

14 
CORRECTION FOR ZONE OF INFLUENCE DUE TO OBSTRUCTED PLUME EFFECT

5-38 

1 

2 Figure 5-35 

3 Determination of Horizontal Plume Shift 

4 

5 Comparison of the FDS simulation predictions of horizontal plume shift to the results determined 

6 for the PSM using Equation 5-19 are provided in Figure 5-36. The values for the distance that 

7 the plume has shifted from the centerline of the electrical enclosure are provided on the y-axis, 

8 and the values for the distance from the centerline of the thermal radiation ZOI are provided on 

9 the x-axis. The results show that for most cases, the thermal radiation ZOI extends farther than 

10 the plume will be shifted by the top obstruction. The data circled above the perfect match line in 

11 Figure 5-36 are all less than 200 °C (392 °C). These data correspond to locations that are 

12 above the plume ZOI for thermoset targets. 

13 
CORRELATION OF OBSTRUCTED PLUME MODELS WITH HESKESTAD PLUME 

PREDICTIONS 

5-39 

1 2 

3 

4 Figure 5-36 

5 Comparison of Horizontal ZOI Resulting from Plume Shift to Thermal Radiation Exposure 

6 

7 A different way to quantify the plume shift is a similar approach to that taken in NUREG/CR8 7010, in which the ignition of cable trays within a stack can be defined as an inverted frustum 

9 (trapezoid) with an angle of expansion of 35° with height. Here, the rate of expansion of the 

10 plume is defined in a similar way, where the base of the frustum is defined as the fire base 

11 height with dimensions equivalent to the plan dimensions of the electrical enclosure. Analyzing 

12 the data in Figure 5-36 using this approach, it can be found that the maximum angle observed 

13 from any FDS simulation of an obstructed plume is 28° from the vertical. In application, this 

14 angle can be treated as 30° for simplicity and conservatism. The illustration of the maximum 

15 extent of a thermal plume ZOI using this approach is provided in Figure 5-37. 

16 

0

0.5

1

1.5

2

2.5

3

0 0.5 1 1.5 2 2.5 3

RPO

RRad

Thermoplastic Targets (6kW/m2) Thermoset Targets (11kW/m2) Perfect Match Line

Plume temperatures

less than 200 ̊C
CORRECTION FOR ZONE OF INFLUENCE DUE TO OBSTRUCTED PLUME EFFECT

5-40 

1 

2 Figure 5-37 

3 Maximum Angle from Horizontal Plume Shift 

4 

5 5.3.8.3 Recommendations 

6 The findings from the FDS simulations demonstrate the following guidance can be applied to 

7 electrical enclosure fires that can be credited as having a solid top obstruction. 

8 

9  The overall zone of influence should be defined using the ball and column concept 

10 introduced in the SDP [19] and described in NUREG/CR-6850, resulting in a cylindrical 

11 shape that incorporates the vertical extent of the plume and the horizontal extent of the 

12 thermal radiation from the fire source. 

13  The height of the column should be defined by Equation 5-6 for configurations in which 

14 the obstructed plume credit is applicable. In all other cases where the obstructed plume 

15 cannot be justified, existing methods shall be used corresponding to unobstructed plume 

16 temperature correlations. 

17  The width of the column should be defined using approved techniques for defining the 

18 horizontal extent of the thermal radiation from the source and the damage threshold of 

19 the most susceptible targets. The obstructed plume shall not be credited for reducing 

20 the extent of the horizontal ZOI at this time. The width defined in this manner (i.e., using 

21 flame radiation models) will always bound the expected horizontal shift of the thermal 

22 plume due to the electrical enclosure top obstruction. 

23  In specific applications where the location of the fire plume is of direct interest to the 

24 analysis, the plume location can be defined to fall within an inverted frustum (trapezoid). 

25 The base shall be defined at the fire base height with plan dimensions equivalent to the 

26 electrical enclosure. At elevations higher than the fire base height, the volume should 

27 expand with an angle of 30° relative to the vertical. The plume has been observed to 

28 always be located within this volume, regardless of the nature of the fuel source or 

29 electrical enclosure geometry. 

30 
CORRELATION OF OBSTRUCTED PLUME MODELS WITH HESKESTAD PLUME 

PREDICTIONS 

5-41 

1 The maximum extent of the ZOI is summarized in Figure 5-38 for both the unobstructed and 

2 obstructed plume cases. 

3 

4 

5 Figure 5-38 

6 Recommended ZOI for an Electrical Enclosure Fire a) Without Top Obstruction Credit, 

7 and b) with Top Obstruction Credit 

8 

6-1

1 6

2 Correction for Zone of Influence Due to Obstructed 

3 Plume Effect 

4 This chapter presents the methodology and the development of an adjustment for the vertical 

5 thermal zone of influence (ZOI) for enclosure fires based on the Fire Dynamics Simulator (FDS) 

6 results presented in Chapter 5. 

7 6.1 Assessment of FDS Simulation Results 

8 The results presented in Chapter 5 have shown that for cases in which the fire plume flow is 

9 obstructed by different geometries, plume temperatures are often reduced above the 

10 obstruction. These reduced temperatures do not appear to be limited to a specific obstruction 

11 geometry, heat release rate (HRR), or fire source diameter. The results have been shown to be 

12 sensitive to some input parameters, and limits of implementation have been provided in Section 

13 6.4, as appropriate. As a result, the vertical ZOI may be modified using the same approach 

14 independent of specific obstruction geometry, HRR, or fire source diameter provided the analyst 

15 applies the methodology with consideration for all of the assumptions and limitations provided in 

16 Section 5.1. 

17 

18 The height above the fire base, ݖ஻, with an obstruction present for which temperatures are high 

19 enough to cause damage can be determined through an algebraic modification of the 

20 Heskestad fire plume correlation shown below as: 

ݖ ஻ൌ ൮஻∙ଽ.ଵቈ ೅బ

ቀ೒೎೛

మഐబ

మቁ

቉

భ

యൗ

ொሶ

೎

మ

యൗ

∆் ൲

ଷ/ହ

 (6-1) ଴ݖ ൅ 21

22 Where, B is the bias observed in the comparison between the plume temperature rise of flows 

23 subject to an obstruction and those predicted by the Heskestad fire plume correlation. Equation 

24 6-1 can be used directly to determine the maximum extent of the thermal plume ZOI for fire PRA 

25 applications. 

26 6.2 Prediction of ZOI Correction 

27 6.2.1 Temperature Rise (Example 1) 

28 Using the values presented in Figure F-3 of NUREG/CR-6850 (Appendix F, page F-6), predict 

29 the exposure temperature for a fire using the existing information for unobstructed plumes, and 

30 the updated information for obstructed plumes. 

31 The required inputs from Figure F-3 of NUREG 6850/CR-6850 (Appendix F, page F-6) are HRR 

32 of 211 kW, fire diameter of 0.6 m, radiative fraction of 0.4, and an assumed ambient 

33 temperature of 20 °C (68 °F). Equation 5-3 (shown again below) was used to predict the plume 

34 centerline temperature for the unobstructed plume. 
CORRECTION FOR ZONE OF INFLUENCE DUE TO OBSTRUCTED PLUME EFFECT

6-2 

∆ܶ ൌ 9.1 ൤ ்బ

൫௚௖೛

మఘబ

మ൯

൨

ଵ

ଷൗ

ܳሶ

௖

ଶ

ଷൗ ሺݖെݖ଴ሻ

ିହ

ଷൗ 1 (6-2) 

2 

3 Equation 5-6 (shown again below), with a bias, B = 0.62, was used to predict the plume 

4 centerline temperature for a plume obstructed by the enclosure top. 

∆ܶ ൌ ܤ ቆ9.1 ൤ ்బ

൫௚௖೛

మఘబ

మ൯

൨

ଵ

ଷൗ

ቇ ܳሶ

௖

ଶ

ଷൗ ሺݖെݖ଴ሻ

ିହ

ଷൗ 5 (6-3) 

6 

7 The results were plotted with both temperature predictions versus the height above the fire 

8 base as illustrated in Figure 6-1, demonstrating a dramatic reduction in plume centerline 

9 temperature predictions for the obstructed plume relative to the unobstructed plume. 

10 

11 

12 

13 Figure 6-1 

14 Unobstructed and Obstructed Temperature Predictions 

15 6.2.2 Zone of Influence (Example 2) 

16 Once again using the values presented in Figure F-3 of NUREG/CR-6850 (Appendix F, page F17 6), predict the maximum thermal plume ZOI height for a fire using the existing information for 

18 unobstructed plumes, and the updated information for obstructed plumes. 

19 

20 The required inputs from Figure F-3 of NUREG/CR-6850 (Appendix F, page F-6) are HRR of 

21 211 kW, fire diameter of 0.6 m (2 ft), radiative fraction of 0.4, and an assumed ambient 

22 temperature of 20 °C (68 °F). No information is provided for the target failure properties; 

0

100

200

300

400

500

600

700

800

900

1000

0 0.5 1 1.5 2 2.5 3

∆

T (C)

Elevation (m)

Unobstructed Obstructed
CORRECTION FOR ZONE OF INFLUENCE DUE TO OBSTRUCTED PLUME EFFECT 

6-3

1 therefore, both thermoset (330 °C (626 °F)) and thermoplastic (205 °C (400 °F)) cables are 

2 evaluated. 

3 

4 Use Equation 6-1 with a bias, B = 1.0, for the unobstructed plume case to evaluate the vertical 

5 plume ZOI elevation. Use the same HRR, fire diameter, assumed radiative fraction, and a bias 

6 of 0.62 to evaluate the vertical plume ZOI elevation for an obstructed plume. The results of this 

7 analysis are provided in Table 6-1, demonstrating a dramatic reduction in plume centerline 

8 temperature predictions. Visual representations of the changes in the vertical ZOI for 

9 obstructed plumes are presented in Figure 6-2. 

10 Table 6-1 

11 Example 2 ZOI Calculations 

Target Type Configuration Bias 

Heat 

Release 

Rate (kW) 

Fire 

Diameter 

(m) 

Radiative 

Fraction 

Ambient 

Temperature 

(°C) 

ZOI 

Height 

(m) 

Thermoplastic 

(205°C) 

Unobstructed 1.0 211 0.6 0.4 20 2.2 

Obstructed 0.62 211 0.6 0.4 20 1.7 

Thermoset 

(330°C) 

Unobstructed 1.0 211 0.6 0.4 20 1.6 

Obstructed 0.62 211 0.6 0.4 20 1.3 

12 

13 

14 Figure 6-2 

15 Vertical Plume ZOI 
CORRECTION FOR ZONE OF INFLUENCE DUE TO OBSTRUCTED PLUME EFFECT

6-4 

1 Comparing these results shows a reduction in the vertical plume ZOI elevation when crediting 

2 the obstruction for reducing the plume centerline temperature. 

3 6.2.3 Zone of Influence Sensitivity (Example 3) 

4 Evaluate the overall sensitivity of the zone of influence for an obstructed plume relative to an 

5 unobstructed plume. 

6 

7 Evaluate the ratio of Equation 6-1 to the Heskestad fire correlation (Equation 6-3) solved for z, 

8 (i.e., Equation 6-1 with B = 1.0). This evaluation shows the change in the ZOI elevation when a 

9 plume flow is subject to an obstruction relative to an unobstructed plume as: 

10 

௭ಳ

௭

ܤ~

య

ఱ ൌ 0.62

య

11 ఱ ൌ 0.75		 	 	 (6-4)

12 

13 The result in Equation 6-4 shows that the ZOI dimension of an obstructed plume is 

14 approximately 75% relative to the size of the initial ZOI evaluated using the Heskestad 

15 correlation. 

16 

17 Alternatively, it is appropriate to evaluate several specific configurations and show the 

18 difference between the two approaches graphically. The results of this analysis are 

19 obtained by solving Equation 6-1 for each of the fire configurations used in this analysis. 

20 The results of this analysis are provided in Figure 6-3, showing the difference in the vertical 

21 ZOI elevations at which fire plume temperatures are estimated to cause damage to 

22 

23 

24 

25 Figure 6-3 

26 ZOI Difference for Obstructed and Unobstructed Plume Flows Using Heskestad Fire 

27 Plume Correlation 

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

5

0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5

ZOI Obstructed (m)

ZOI Unobstructed (m)

Perfect Match Line 330 C 205 C Bias
CORRECTION FOR ZONE OF INFLUENCE DUE TO OBSTRUCTED PLUME EFFECT 

6-5

1 

2 thermoset (330°C (626 °F)) and thermoplastic (205 °C (400 °F)) cables. The difference in the 

3 ZOI can be calculated as a bias following the technique outlines in the FDS manual, or in this 

4 case a linear correlation fit. The resulting bias is 0.76, showing a decrease in vertical ZOI of 

5 around 24% for fire plume flows subject to an obstruction. This closely matches the calculated 

6 change in elevation presented in Equation 6-4. 

7 

8 An analyst may use this information to estimate the reduction in overall risk that can be 

9 attributed to implementing the obstructed plume information provided in this report. The 

10 reduced ZOI may result in fewer risk important targets being exposed by the ignition source, 

11 and therefore reduced risk in the fire PRA. 

12 6.2.4 Fire Protection SDP Application (Example 4) 

13 During an inspection, it was noted that a section of fire wrapped cable tray was not properly 

14 maintained. This section of cable tray was noted to be within the plume ZOI of an electrical 

15 enclosure that was previously screened from the PRA analysis. The inspection finding initiated 

16 an SDP analysis of the configuration. 

17 The electrical enclosure has a height of 2.3 m (7.5 ft) and width (diameter) of 0.9 m (3 ft), and 

18 the fire base height is specified as 2.0 m (6.6 ft) in accordance with the guidelines of 

19 NUREG/CR-6850 Supplement 1. The electrical enclosure is located in a compartment with a 

20 very high ceiling, and the development of a hot gas layer (HGL) has been screened based on 

21 detailed fire modeling of the worst configuration in the compartment. The electrical enclosure 

22 contains non-qualified, thermoplastic cables, and has been assigned an HRR of 464 kW based 

on NUREG/CR-6850 guidance for the 98th 23 percentile fire size. The ambient temperature in the 

24 compartment is 20  ̊C (68  ̊F). The cable tray contains thermoplastic cables and is located at an 

25 elevation of 4.9 m (16 ft) above the floor. The separation between the fire base and the cable 

26 tray is 2.9 m (9.5 ft). The ZOI height from the table values presented in NUREG/CR-6850 

27 Figure F-3 is 3.2 m (10.5 ft), confirming that the cable tray is within the plume ZOI for an 

28 unobstructed plume. A diagram of the configuration evaluated is provided in Figure 6-4. 

29 However, the electrical enclosure has a solid top with no openings in the top surface. The 

30 electrical enclosure has sufficient side venting to fit the requirements to be treated as an 

31 obstructed plume configuration. The analysis is then performed using the obstructed plume 

32 credit as detailed above. Using Equation 6-1 with a bias, B=0.62, the total vertical ZOI is 

33 reduced to 2.3 m (7.5 ft) from the fire base height. Therefore, the cable tray is outside the 

34 obstructed electrical enclosure ZOI and only the enclosure itself will fail during the event 

35 analysis. A further reduction in the vertical ZOI could be credited to the analysis by using the 

36 400 kW HRR as described in Table 4-2 of this report for large, closed enclosures with 

37 unqualified cables, but the additional analysis is unnecessary. 
CORRECTION FOR ZONE OF INFLUENCE DUE TO OBSTRUCTED PLUME EFFECT

6-6 

1 

2 Figure 6-4 

3 Example 4, Reduction in Vertical ZOI Due to Obstructed Plume Credit 

4 

5 6.2.5 Fire PRA Application (Example 5) 

6 An electrical enclosure fire scenario is being considered for inclusion in the Fire PRA. The 

7 electrical enclosure is considered to contain multiple bundles of unqualified cable, with closed 

8 doors, and will be treated as a Group 4a Enclosure class fire with 400 kW peak heat release 

9 rate per Table 4-2 of this report. The enclosure has a solid top with no opening, and vents 

10 located on two of the four sides of the enclosure approximately 0.3 m (1 ft) below the top of the 

11 enclosure. The enclosure has a height of 2.3 m (7.5 ft) and assumed diameter of 0.9 m (3 ft). 

12 The enclosure is located in a compartment with a very high ceiling, and the development of an 

13 HGL has been screened based on detailed fire modeling of the worst configuration in the 

14 compartment. The ambient temperature in the compartment is 20  ̊C (68  ̊F). 

15 Two cable trays containing unqualified thermoplastic cables are located above the electrical 

16 enclosure. One of the cable trays, cable tray 1, is located within the plume ZOI of the electrical 

17 enclosure, and is considered to ignite as a secondary combustible. The second cable tray, 

18 cable tray 2, is located outside of the ignition source ZOI; however, the combined ZOI of the 

19 electrical enclosure and the burning cable tray 1 is considered to damage tray 2. Both trays are 

20 located at an elevation of 4.7 m (15.4 ft) from the floor. 

21 Following the guidance outlined in NUREG/CR-6850 assuming the fire is at the top of the 

22 electrical enclosure, using Equation 6-1 with a bias, B=1.0, assuming an unobstructed source, 

23 the vertical distance above the source for which a thermoplastic cable would be damaged is 

24 2.8 m (9.2 ft). Following the guidance outlined in Supplement 1 to NUREG 6580 (EPRI 
CORRECTION FOR ZONE OF INFLUENCE DUE TO OBSTRUCTED PLUME EFFECT 

6-7

1 1019259) and placing the source at an elevation of 0.3 m (1 ft) below the top of the enclosure, 

2 the total vertical ZOI for this enclosure is found to be 4.8 m (15.7 ft) above the floor. This means 

3 that cable tray 1 is within the vertical plume ZOI of an unobstructed plume. As a result, cable 

4 tray 2 is damaged by the combined ZOI of the electrical enclosure and cable tray 1. 

5 Repeating the analysis and crediting the effect of the obstruction caused by the enclosure, a 

6 different result is estimated. Returning to Equation 6-1 and using a bias, B=0.62, the total 

7 vertical ZOI becomes 4.1 m (13.5 ft) from the floor. Now, both cable trays are outside the 

8 electrical enclosure ZOI. A comparison of the change in the ZOI following the two estimates is 

9 presented graphically in Figure 6-5. 

10 

11 Figure 6-5 

12 NFPA 805 Example Reduction of Vertical ZOI 

13 

14 In Figure 6-5, the solid red box represents the initial ZOI for the “unobstructed” electrical 

15 enclosure. The first and second damage states presented in the event tree above are reached 

16 by damage to the electrical enclosure and the cable tray 1 which fall within this ZOI. The larger 

17 box, bounded by the red dashed line, represents the increased ZOI resulting from the combined 

18 burning of the electrical enclosure and cable tray 1. Cable tray 2 is within this larger ZOI and 

19 therefore damaged (the third damage state in the event tree above). 

20 Accounting for the obstruction of the enclosure top, the blue solid box represents the modified 

21 ZOI for the electrical enclosure. The reduction to the vertical ZOI limits the damage to the 

22 electrical enclosure itself, and all subsequent damage states are unnecessary. 

23 6.3 Plume Temperature and ZOI Corrections 

24 In the FDS simulations, an area of limited information for estimating the vertical damage ZOI for 

25 fire plumes subject to an obstruction such as the top surface of an electrical enclosure was 

26 explored. Data for exploration into this phenomenon was developed using FDS Version 6.0.1 to 

27 produce a series of simulations in support of this analysis. Results from these simulations were 
CORRECTION FOR ZONE OF INFLUENCE DUE TO OBSTRUCTED PLUME EFFECT

6-8 

1 used to justify correction to the Heskestad fire plume correlation to estimate the change in the 

2 vertical damage ZOI. A number of different parameters, including the heat release rate, the fire 

3 source diameter, the fire source elevation, and the geometry of the obstruction, are varied to 

4 determine their influence on the fire plume temperature rise. 

5 

6 The information provided for estimating the reduced vertical damage ZOI observed is 

7 independent of, and is applicable over, varying ranges of HRR, fire source diameters, and 

8 obstruction geometries. Therefore, the provided information is appropriate for representing the 

9 hazards to cables due to fire plume temperatures for practical applications in the commercial 

10 nuclear power industry. 

11 

12 Results suggest that a reduction of 38% (i.e., 1-B = 1-0.62 = 0.38) is appropriate when 

13 estimating the plume temperature rise above an obstruction using the Heskestad fire plume 

14 correlation. As a result of the change in plume temperature rise, an approximate 24% reduction 

15 in the vertical damage ZOI dimension for fire plume flows above an obstruction is observed. The 

16 reduced ZOI may result in fewer risk important targets being exposed by the ignition source, 

17 and therefore reduced risk in the fire PRA. 

18 6.4 Application of the Correction 

19 The obstructed plume analysis was subjected to a limited peer review. Through analysis of the 

20 results and the assumptions and limitations stated in Section 5.1.5, the following limits are 

21 provided for the implementation of the obstructed plume correction: 

22 

23  The obstructed plume correction does not apply to fires with a base elevation located 

24 below the half height of the enclosure. Results suggest that fires located below the half 

25 height of the enclosure may produce plume temperatures equivalent to an unobstructed 

26 plume. Therefore, in scenarios where the fire base elevation is considered below the 

27 half height of the enclosure, the plume should be treated as an unobstructed plume. 

28 This limitation may not have any impact in commercial nuclear applications, since 

29 current fire PRA information recommends fires be located near the top of electrical 

30 enclosures (see Chapter 12 of Ref. 15). 

31 

32  The obstructed plume correction does not apply to electrical enclosures that have a 

33 cumulative opening on the top plate greater than 5% of its total surface area. Therefore, 

34 any enclosure with a cumulative opening greater than 5% should be treated as an 

35 unobstructed configuration. Note that an enclosure top may have penetrations, but only 

36 as long as those penetrations are properly sealed such that they do not contribute to the 

37 cumulative opening area. Properly sealed openings include cables inside steel conduit 

38 that is fitted tightly at the top plate interface, and other penetrations sealed with 

39 approved non-combustible wrap materials. 

40 

41  The obstructed plume correction does not apply to configurations that include burning of 

42 secondary combustible materials. The obstructed plume correlation, however, may be 

43 used to establish the likelihood that secondary combustibles may be ignited through the 

44 definition of the primary ignition source ZOI. The obstructed plume correction is limited 

45 to the ignition source only. That is, in the case of secondary combustible ignition (i.e., 

46 cable trays), the subsequent analysis should follow existing information and modeling 

47 techniques. 

48 
CORRECTION FOR ZONE OF INFLUENCE DUE TO OBSTRUCTED PLUME EFFECT 

6-9

1  The obstructed plume correction does not apply to analysis that determines the hot gas 

2 layer (HGL) damage. The plume correction may only be used for the duration of time in 

3 which thermal plume exposure is postulated but hot gas layer temperature has not 

4 reached the damage criteria. Existing information and modeling techniques should be 

5 used to evaluate the likelihood and timing of hot gas layer damage. Modeling 

6 techniques exist that can combine the effects of a thermal plume immersed in a hot gas 

7 layer, although these techniques may only be applied to exposures within the thermal 

8 plume prior to the hot gas layer damage state. 

9 

10  The obstructed plume correction does not apply to analyses that determine the visibility 

11 reduction due to smoke accumulation. Smoke accumulation has not been evaluated 

12 directly in this report, and the findings of this report do not invalidate existing guidelines 

13 for the evaluation of visibility. 

14 

15  The obstructed plume correction may be applied to the evaluation of the ceiling jet 

16 damage ZOI; however, careful consideration must be observed that the correction 

17 technique considers the remaining assumptions and limitations specified in Section 

18 5.1.5. Application to the ceiling jet ZOI is justified by the direct association of the ceiling 

19 jet temperature with the thermal plume temperature. 

20 

21  The obstructed plume correction does not apply to the evaluation of the horizontal 

22 thermal flame radiation ZOI. Existing information and modeling techniques should be 

23 used to evaluate the extent of the horizontal ZOI. The overall extent of the ZOI should 

24 be evaluated following the guidance in Section 5.3.8. 

25 

26  The bias due to obstructed plume is not applicable to reducing the flame temperature; 

27 however, the current information should be applied to direct flame exposures. 

28 

29  The bias recommended in this report shall not be applied to FDS predictions of plume 

30 temperatures. The bias correction does not apply to FDS results and is only intended for 

31 use with the Heskestad correlation. A qualified user of FDS should develop an 

32 appropriate set of inputs to address the effects of enclosure obstructions directly, and 

33 not by adjusting the output data with a bias correction. 

34 

35 

7-1 

1 7

2 Summary, Conclusions, and Future Research 

3 This chapter summarizes the results and conclusions described in this report with the objective 

4 of consolidating the new information for the practical application of this research. This chapter 

5 starts by listing the main objectives of this study so that they serve as the framework for the 

6 summary and conclusions. The specific objectives of this report are: 

7 

8 1. The classification of electrical enclosures in terms of function, size, content, and 

9 ventilation conditions, 

10 2. The determination of peak heat release rate probability distributions considering specific 

11 electrical enclosure characteristics such as function, size, ventilation conditions, and 

12 combustible content, and 

13 3. The characterization of fire plumes associated with fires in electrical enclosures. 

14 

15 The objectives listed above have been addressed through research focused in a number of 

16 technical areas. In order to address the classification of electrical enclosures and their 

17 corresponding flammability characterization, the results of a number of experimental test 

18 programs were evaluated. In addition, an extensive review of the fire events data that had been 

19 collected by EPRI was conducted in an effort to reflect the fire experience at NPPs in the 

20 provided enclosure classifications and the peak heat release rate probability distributions. 

21 

22 The practical implication of the provided electrical enclosure classification and peak heat 

23 release rate probability distributions is the ability to calculate severity factors that better reflect 

24 characteristics of the electrical enclosures. It should be noted that the severity factors are 

25 calculated using the methodology currently described in Chapter 8 and Appendices E and F of 

26 NUREG/CR-6850. 

27 

28 In order to address the characterization of plumes generated by fires in electrical enclosures, a 

29 number of fire simulations were conducted using the Fire Dynamics Simulator (FDS) program. 

30 Fire plumes generated by fires inside an electrical enclosure may be obstructed by the 

31 enclosure walls, disrupting the fire induced flows, and at the same time producing different 

32 temperature profiles within the fire plume. The temperature profiles of these obstructed fire 

33 plumes were analyzed to develop information for determining a vertical component of the zone 

34 of influence reflecting fires inside electrical enclosures. The recommendations for determining a 

35 vertical component of the zone of influence considering fires inside the electrical enclosure relax 

36 the assumption in existing fire PRA information that fires are postulated outside the enclosures. 

37 

38 The research described above is bounded by specific assumptions and limitations that must be 

39 accounted for when applying the methodology in practical applications. To clarify these 

40 assumptions and limitations, detailed example applications have been developed and included 

41 in this report. The examples are intended to illustrate the implementation of the provided 

42 approach within the context of a fire PRA or fire modeling analysis. 

43 

44 A summary of the results of this research is described in the following sections. 
SUMMARY, CONCLUSIONS, AND FUTURE RESEARCH

7-2 

1 7.1 Classification of Electrical Enclosures 

2 A new classification of electrical enclosures has been developed. This new classification is 

3 based on cabinet function, volumetric size, combustible content, and ventilation configuration. 

4 The new classification options are intended to more accurately represent the electrical 

5 enclosure population and simplify the process of determining which peak heat release rate 

6 probability distribution is assigned to the electrical enclosure. 

7 

8 Based on electrical function, the electrical enclosures are grouped as follows: 

9 

10  Switchgear and load centers 

11  Motor control centers and battery chargers 

12  Power inverters 

13 

14 The classification above is mostly for enclosures associated with power distribution. Other 

15 electrical enclosures identified as ignition sources are classified based primarily on volumetric 

16 size as follows: 

17 

 Large enclosures, characterized by having a volume larger than 1.4 m3

 (50 ft3 18 ), 

 Medium enclosures, characterized by having volumes between 0.34 m3

 (12 ft3 19 ) and 

1.4 m3

 (50 ft3 20 ), and 

 Small enclosures, characterized by having volumes smaller than 0.34 m3

 (12 ft3 21 ). 

22 

23 Examples of these electrical enclosures include relay panels, termination cabinets, the main 

24 control board, etc. The initial classification of these enclosures by volumetric size provides an 

25 easy grouping process consisting of visual examination external to the enclosure during 

26 walkdowns. Large and medium volumetric classifications can be refined to account for the 

27 amount of combustible fuel loads, type of cable insulation material, and their ventilation 

28 configuration. These refinements can result in lower heat release rate values based on visual 

29 inspection of the cabinet internals. 

30 7.2 Peak Heat Release Rate Probability Distributions 

31 The classification described in the previous section provides the framework for assigning 

32 probability distributions for the peak heat release rate associated with the electrical enclosures. 

33 Selected probability distributions for peak heat release rates were originally described in 

34 NUREG/CR-6850 and applied to a given enclosure based on three factors: qualified versus 

35 unqualified cable, open versus closed enclosures, and single versus multiple cable bundles that 

36 could be ignited. This report described the new probability distributions with direct 

37 correspondence to the classification described earlier. It should be noted that the probability 

38 distributions described in Appendices E and G of NUREG/CR-6850 may not need to be 

39 replaced with the ones described in this report, as they are bounding. 

40 

41 The revised peak HRR probability distributions (i.e., gamma distributions) for each of the new 

42 enclosure classification groups were developed based on the following factors: 

43 

44  Review of experimental factors and configurations in testing programs intended to 

45 assess the heat release rate generated by electrical enclosure fires. Both domestic and 

46 international test programs were included within the scope of this research. 

47  Statistical analysis of the applicable experimental results. 
SUMMARY, CONCLUSIONS, AND FUTURE RESEARCH

7-3 

1  Extensive review and comparison of existing electrical enclosures configuration and 

2 operating experience in commercial nuclear plants and the influencing experimental 

3 factors. 

4 

The distributions are defined based on the 75th and 98th percentile values, with the 98th 5 

6 percentile value intended for use as the maximum HRR to be assumed for any enclosure in a 

given type/function classification group. The 98th 7 percentile value is also the value provided for 

8 use during ignition source screening as currently described in Chapter 8 and Appendix G of 

9 NUREG/CR-6850. 

10 

11 Table 7-1 presents the electrical enclosure classifications and the provided peak HRR 

12 probability distributions. 

13 

14 

15 
Table 7-1 1 

Peak Heat Release Rate Distributions for Electrical Enclosures 2 

Enclosure 

Class/Function 

Group 

Enclosure 

Ventilation 

(Open/Closed 

Doors) 

Fuel Type* 

(TS/TP 

Cables) 

Gamma Distribution Characteristics 

(a) Default (b) Low Fuel Loading (c) Very Low Fuel Loading 

Alpha Beta 

75th

Percentile 

(kW) 

98th

Percentile 

(kW) 

Alpha Beta 

75th

Percentile 

(kW) 

98th

Percentile 

(kW) 

Alpha Beta 

75th

Percentile 

(kW) 

98th

Percentile 

(kW) 

1 - Switchgear 

and Load 

Centers 

Closed TS 0.32 79 30 170 Closed TP 0.99 44 60 170 

2 - MCCs and 

Battery 

Chargers 

Closed TS 0.36 57 25 130 Closed TP 1.21 30 50 130 NOT APPLICABLE 

3 - Power 

Inverters 

Closed TS 0.23 111 25 200 Closed TP 0.52 73 50 200 

4a - Large 

Enclosures 

[>1.42 m3

(>50 ft3)] 

Closed TS 0.23 223 50 400 0.23 111 25 200 0.38 32 15 75 Closed TP 0.52 145 100 400 0.52 73 50 200 0.88 21 25 75 

Open TS 0.26 365 100 700 0.26 182 50 350 0.38 32 15 75 Open TP 0.38 428 200 1000 0.38 214 100 500 0.88 21 25 75 

4b - Medium 

Enclosures 

[≤1.42 m3

(50 ft3)] and 

> 0.34 m3 (12 

ft3)

Closed TS 0.23 111 25 200 0.27 51 15 100 0.88 12 15 45 Closed TP 0.52 73 50 200 0.52 36 25 100 0.88 12 15 45 

Open TS 0.23 182 40 325 0.19 92 15 150 0.88 12 15 45 Open TP 0.51 119 80 325 0.30 72 25 150 0.88 12 15 45 

4c - Small 

Enclosures 

[≤ 0.34 m3

(12 ft3)] 

Not Applicable TS or TP 0.88 12 15 45 NOT APPLICABLE 

* Per Sections 1.3 and 2.2.2, qualified TP cables (cables that have been tested and passed the IEEE-383 vertical flame spread test) and SIS 3 

wire may be mapped to the TS fuel type groups. 4 

____________________________________________________________________________ 

SUMMARY, CONCLUSIONS, AND FUTURE RESEARCH

7-4
SUMMARY, CONCLUSIONS, AND FUTURE RESEARCH 

7-5 

1 7.3 Obstructed Plume Analysis 

2 The investigation of fire plume temperature subject to obstructed flows was conducted using the 

3 Fire Dynamics Simulator (FDS) fire modeling program. The fire scenario configurations 

4 investigated are intended to mimic those created by fires burning inside electrical enclosures 

5 and are limited to thermal plume conditions in the early stages of the fire (i.e., before significant 

6 room temperature increases). 

7 

8 This study developed a characterization of fire plume temperatures subject to an obstruction so 

9 that specific information can be provided on determining the vertical component of the zone of 

10 influence. Results suggest that a reduction of 38% is appropriate when estimating the plume 

11 temperature rise above an obstruction and using the Heskestad fire plume correlation. As a 

12 result of the change in plume temperature rise, an approximate 24% reduction in the vertical 

13 damage ZOI dimension for fire plume flows above an obstruction is observed. Analysts are 

14 referred to Section 6.4 for specific information and restrictions on the application of these 

15 factors. 

16 7.4 Example Applications 

17 Examples consolidating the information described in this report were developed and included in 

18 Appendix F. These examples have been selected and designed to illustrate how to incorporate 

19 the provided methodology for modeling in electrical enclosures. The examples specifically 

20 address how to account for the assumptions and limitations associated with the research and 

21 information documented in this report. 

22 7.5 Future Research 

23 During the working group meetings, a number of topics were discussed with potential to impact 

24 the realism in modeling electrical enclosure fires and fire probabilistic risk assessments. A new 

25 classification system for electrical enclosures, revised peak heat release rate probability 

26 distributions, and an obstructed plume analysis methodology were three topics that were 

27 discussed and are presented in this report. A number of areas have been left for future 

28 research. The panel intends to reconvene and discuss if there are any remaining topics that 

29 should be pursued in the future. In addition, the U.S. Nuclear Regulatory Commission is 

30 initiating a series of fire tests to further explore the fire hazards associated with electrical 

31 cabinets. 

32 

33 

8-1 

1 8

2 References 

3 1. NFPA 805, “Performance-Based Standard for Fire Protection for Light-Water Reactor Electric 

4 Generating Plants,” 2001 Edition, National Fire Protection Association, Quincy, MA. 

5 2. 10 CFR 50.48 (Title 10 of the Code of Federal Regulations, Part 50, Section 50.48), “Fire 

6 Protection.” 

7 3. Appendix R to 10 CFR 50, “Fire Protection Program for Nuclear Power Facilities Operating Prior 

8 to January 1, 1979.” 

9 4. NUREG/CR-6850 and EPRI 1011989, “EPRI/NRC-RES Fire PRA Methodology for Nuclear 

10 Power Facilities,” Volume 1: Summary and Overview and Volume 2: Detailed Methodology. 

11 Electric Power Research Institute, Palo Alto, CA and U.S. Nuclear Regulatory Commission, 

12 Office of Nuclear Regulatory Research (RES) Rockville, MD, September 2005. 

13 5. EPRI 1022993, “Evaluation of Peak Heat Release Rates in Electrical Cabinet Fires – Reanalysis 

14 of Table G-1 of NUREG/CR-6850 and Table G-1 of EPRI 1011989,” Electric Power Research 

15 Institute, Palo Alto, CA, February 2012. 

16 6. NRC comments on the Recent Fire PRA Methods Review Panel Decisions and EPRI 1022993, 

17 “Evaluation of Peak Heat Release Rates in Electrical Cabinet Fires.” ML12172A406, June 20, 

18 2012. 

19 7. NUREG/CR-7197, “Heat Release Rates of Electrical Enclosure Fires (HELEN-FIRE),” K. 

20 McGrattan, S. Bareham, National Institute of Standards and Technology, draft, October 2014. 

21 8. NUREG/CR-4527, “An Experimental Investigation of Internally Ignited Fires in Nuclear Power 

22 Plant Control Cabinets,” J. Chavez, SAND86-0336, Volumes 1 and 2, April 1987. 

23 9. VTT Publications 186, “Full Scale Fire Experiments On Electronic Cabinets,” J. Mangs and O. 

24 Keski-Rahkonen, VTT Technical Research Centre of Finland, 1994. 

25 10. VTT Publications 269, “Full Scale Fire Experiments On Electronic Cabinets II,” J. Mangs and O. 

26 Keski-Rahkonen, VTT Technical Research Centre of Finland, 1996. 

27 11. VTT Publications 521, “On the Fire Dynamics of Vehicles and Electrical Equipment,” J. Mangs 

28 and O. Keski-Rahkonen, VTT Technical Research Centre of Finland, 2004. 

29 12. Plumecocq, W., M. Coutin, S. Melis, L. Rigollet, Characterization of Closed-Doors Electrical 

30 Cabinet Fires in Compartments, Fire Safety Journal 46, 2011. 

31 13. NUREG-2169 and EPRI 3002002936, “Nuclear Power Plant Fire Ignition Frequency and Non32 Suppression Probability Estimation Using the Updated Fire Events Database,” Electric Power 

33 Research Institute, Palo Alto, CA and U.S. Nuclear Regulatory Commission, Office of Nuclear 

34 Regulatory Research (RES) Rockville, MD, December 2014. 

35 14. FAQ 13-0006, “Modeling Junction Box Scenarios in a Fire PRA,” Rev. 0, F. Joglar, May 2013. 

36 15. NUREG/CR-6850, Supplement 1, “Fire Probabilistic Risk Assessment Methods 

37 Enhancements,” EPRI 1019259, Electric Power Research Institute, Palo Alto, CA and U.S. 

38 Nuclear Regulatory Commission, Office of Nuclear Regulatory Research (RES) Rockville, MD, 

39 September 2010. 
REFERENCES

8-2 

1 16. FAQ 14-0009, “Treatment of Well-Sealed Electrical Panels Greater than 440V,” Rev. D, NextEra 

2 Energy, July 1, 2014. 

3 17. National Institute of Standards and Technology (NIST), Fire Dynamics Simulator (FDS) User’s 

4 Guide, Version 6.0.1, NIST Special Publication 1019, Sixth Edition, November 2013. 

5 18. NUREG-1934 and EPRI 1023259, “Nuclear Power Plant Fire Modeling Analysis Guidelines 

6 (NPP FIRE MAG) – Final Report,” Electric Power Research Institute, Palo Alto, CA and U.S. 

7 Nuclear Regulatory Commission, Office of Nuclear Regulatory Research (RES) Rockville, MD, 

8 November 2012. 

9 19. Technical Basis for Fire Protection Significance Determination Process (IMC 0609, Appendix F) 

10 At Power Operations, February 2005. 

11 20. NUREG-1824, Verification and Validation of Selected Fire Models for Nuclear Power Plant 

12 Applications, Volume 1: Main Report, EPRI 1011999, Electric Power Research Institute, Palo 

13 Alto, CA and U.S. Nuclear Regulatory Commission, Office of Nuclear Regulatory Research 

14 (RES) Rockville, MD, May 2007. 

15 21. NUREG-1824, Verification and Validation of Selected Fire Models for Nuclear Power Plant 

16 Applications, Volume 7: Fire Dynamics Simulator (FDS), EPRI 1011999, Electric Power 

17 Research Institute, Palo Alto, CA and U.S. Nuclear Regulatory Commission, Office of Nuclear 

18 Regulatory Research (RES) Rockville, MD, May 2007. 

19 22. Heskestad, Gunnar. “Engineering Relations for Fire Plumes.” Fire Safety Journal 7.1, pp 25-32, 

20 1984. 

21 23. NUREG-1805, “Fire Dynamics Tools (FDTs) – Quantitative Fire Hazard Analysis Methods for 

22 the U.S. Nuclear Regulatory Commission Fire Protection Inspection Program,” Supplement 1, 

23 Volumes 1 & 2, June 2013. 

24 24. FAQ 13-0004, “Clarifications on Treatment of Sensitive Electronics,” NextEra Energy, Rev. 1, 

25 June 26, 2013. 

26 25. NFPA 13, National Fire Protection Association Standard for the Installation of Sprinkler 

27 Systems. National Fire Protection Association, 2010. 

28 26. Davis, W. D., G. P. Forney, and R. W. Bukowski, "Developing Detector Siting Rules from 

29 Computational Experiments in Spaces With Complex Geometries." Fire Safety Journal 29.2, pp 

30 129-139, 1997. 

31 27. U.S. NRC Generic Letter No. 86-10, “Implementation of Fire Protection Requirements,” April 

32 1986. 

33 28. Beyler, C. L. “Fire Plumes and Ceiling Jets.” Fire Safety Journal 11.1, pp 53-75, 1986. 

34 29. Zukoski, E. E., T. Kubota, and B. Cetegen. “Entrainment in Fire Plumes,” Fire Safety Journal 

35 3.3, pp 107-121, 1981. 

36 30. McGrattan, K.B., et al., “Fire Dynamics Simulator User’s Guide,” National Institute of Standards 

37 and Technology and VTT Technical Research Centre of Finland, Sixth Edition, November 2013. 

38 31. McGrattan, K. B., et al., “Fire Dynamics Simulator, Technical Reference Guide, Volume 1: 

39 Mathematical Model,” National Institute of Standards and Technology and VTT Technical 

40 Research Centre of Finland, Sixth Edition, April 2013. 

41 32. McGrattan, K. B., et al., “Fire Dynamics Simulator, Technical Reference Guide, Volume 2: 

42 Verification Guide,” National Institute of Standards and Technology and VTT Technical 

43 Research Centre of Finland, Sixth Edition, November 2013. 
REFERENCES

8-3 

1 33. McGrattan, K. B., et al., “Fire Dynamics Simulator, Technical Reference Guide, Volume 3: 

2 Validation,” National Institute of Standards and Technology and VTT Technical Research Centre 

3 of Finland, Sixth Edition, November 2013. 

4 34. Heskestad, G., “Fire Plumes, Flame Height, and Air Entrainment,” Section 2–1, SFPE 

5 Handbook of Fire Protection Engineering, 4th Edition, 2008. 

6 35. Janssens, M., “Calorimetry,” Section 3-2, “The SFPE Handbook of Fire Protection Engineering,” 

7 4th Edition, 2008. 

8 36. EPRI 3002000830, “Fire-Induced Vulnerability Evaluation (FIVE) User’s Guide Revision 2,” 

9 Electric Power Research Institute, Palo Alto, CA, 2014. 

10 

11 

12 

A-1 

1 Appendix A

2 WG Members, Non-WG Contributors, and Facilitator 

3 Resumes 

4 

5 This appendix presents the resumes of the working group (WG) members and the facilitator. 

6 Also, it includes the resumes of two non-WG experts who performed the obstructed plume 

7 simulations using the FDS fire modeling program. 

8 
WG MEMBERS, NON-WG CONTRIBUTORS, AND FACILITATOR RESUMES 

A-2 

1 Joelle DeJoseph, Duke Energy 

2 

 EDUCATION 3 4 

5 University of Maryland, College Park, MD; May 2004 

6 Masters of Science; Major: Fire Protection Engineering 

7 Stevens Institute of Technology, Hoboken, NJ; May 1999 

8 Bachelor of Engineering; Major/Concentration: Mechanical Engineering/Manufacturing 

9 New York University, New York, NY; May 1999 

10 Bachelor of Science; Major/Minor: Mathematics/Computer Applications 

11 Registrations: Professional Engineer (P.E.) – North Carolina #033827 

12 Fundamentals of Engineering (E.I.T.) – Massachusetts #21069 

13 

14 EXPERIENCE 

15 

16 Duke Energy, Nuclear Generation Group, Raleigh, NC April 2010-present 

17 Fire Protection Engineer, Senior Engineer 

18  Fire Protection engineering supporting fire Probabilistic Rick Assessment (PRA) 

19 development for Duke Energy sites, including walkdowns and fire modeling 

20  Lead the transition to the NFPA 805 performance based approach for fire 

21 protection at two nuclear power plants 

22  Fire modeling lead for fleet fire protection at Duke Energy 

23  Fire PRA Peer review 

24  NFPA 805 License Amendment Request (LAR) audit team lead 

25  NFPA 805 LAR Request for Additional Information (RAI) response experience 

26  Subject matter expert for NFPA 805 monitoring, Very Early Warning Fire 

27 Detection Systems (VEWFDS), and surveillance optimization 

28  Fire Protection Program Manager experience at a nuclear power plant 

29  Fire Protection System Engineer experience at a nuclear power plant 

30 

31 Kidde Aerospace and Defense, Wilson, NC September 2006-March 2010 

32 Fire Protection Development Engineer, Ground Vehicles 

33  Develop fire suppression (explosion protection) extinguisher for use in military 

34 ground vehicles 

35  Evaluate fire extinguishing agent effects on crew, including acid gas (specifically 

36 HF) concentration, discharge force, and decibel level 

37  Responsible for overseeing production manufacturing, including procurement, 

38 process, welding and pressure testing, first article inspection and conformance 

39 

40 Hughes Associates, Inc., Warwick, RI July 2004-September 2006 

41 Fire Protection Engineer 

42  Provide design, design review, and specification development of fire protection 

43 systems. Work experience includes specification of system performance criteria, 

44 composition of design drawings, review of shop drawings, inspection of 

45 compliance with applicable codes and standards, and acceptance testing of 

46 installed systems. 

47  Developed and evaluated performance-based design alternatives 

48  Provided design analysis of new and existing life safety systems 

49  Audited and tested existing fire protection systems 
WG MEMBERS, NON-WG CONTRIBUTORS, AND FACILITATOR RESUMES 

A-3

1  Review of building code, fire prevention, and reference documents as they 

2 pertain to client issues 

3 

4 University of Maryland, College Park, MD July 2003-June 2004 

 5Graduate Research Assistant, Yucca Mountain Project 

6  Development and implementation of a tunnel tenability assessment methodology 

7  Estimated intensity and duration of the fire source term for the postulated fire 

8  Calculated fire-induced conditions, including visibility, temperature, and gas 

9 concentrations, resulting from the specified fire source as a function of time and 

10 location 

11  Established risk and assess impact on project 

12  Review outside work, including methodologies and calculations 

13 

14 Bureau of Alcohol, Tobacco, and Firearms, Beltsville, MD July 2003-December 2003 

15 Fire Research Laboratory, Student Intern 

16  Set-up and testing of research equipment 

17  Arrange and run test experiments for fire investigator classes 

18  Collect and document data for test fires 

19 

20 Affiliated Engineers Metro DC, Rockville, MD September 2002-July 2003 

21 Affiliated Engineers NW, Seattle, WA April 2001-August 2002 

22 Plumbing, Piping, and Fire Protection Design Engineer 

23  Design of plumbing and piping systems for major buildings: universities, hospitals, 

24 research centers, etc. 

25  Comprehensive analytical assessment of water, compressed air, vacuum, specialty gas 

26 systems for commercial uses 

27  Liaison between client, architect, and contractor concerning city building code and 

28 regulations 

29 

30 Jaros Baum & Bolles, New York, NY July 1999-September 2000 

31 Plumbing and Fire Protection Design Engineer 

32  Design of entire plumbing and fire protection systems for major commercial buildings: 

33 office buildings, hotels, financial institutions, etc. 

34  Comprehensive analytical assessment of water systems for domestic and fire protection 

35 requirements; incl. detailed hydraulic and load calculations 

36  Liaison between client, architect, and contractor concerning city building code and 

37 regulations 

38 

39 PRESENTATIONS 

40 

41  NRC Commission Briefing on NFPA 805, Fire Protection, June 19, 2014 

42  NEI Fire Protection Forum 2013: Safety and Operational Improvements at Harris 

43 Nuclear Plant 

44  NEI Fire Protection Forum 2013: Very Early Warning Fire Detection System (VEWFDS) 

45 Studies 
WG MEMBERS, NON-WG CONTRIBUTORS, AND FACILITATOR RESUMES 

A-4 

1 Francisco Joglar, Jensen Hughes 

2 

EDUCATION 3 

Ph.D., Reliability Engineering, University of Maryland, 2000 4 

M.S., Fire Protection Engineering, University of Maryland, 1998 5 

B.S., Industrial Engineering, University of Puerto Rico, 1997 6 

Registered PE 7 

VA, No. 038817 (2004) 8 

9 

Dr. Francisco Joglar, PE, is a Senior Consultant with 14 years’ experience. Dr. Joglar has a 10 

strong background in fire modeling, statistics and uncertainty analysis. Since 2001, he has 11 

been researching and consulting in fire protection engineering and probabilistic risk 12 

assessment for the commercial nuclear industry. In the research area, he has been 13 

developing fire protection and fire risk technology for the Electric Power Research Institute 14 

(EPRI) and supporting joint research projects between EPRI and the US NRC Office of 15 

Research. In the consulting area, he has participated in numerous fire modeling and fire risk 16 

projects in various capacities including fire risk analyst, technical lead, project manager, and 17 

technical oversight. For the last six years, Dr. Joglar has been teaching a master degree 18 

level course in fire risk analysis at the University of Maryland, Department of Fire Protection 19 

Engineering. He also teaches a master degree level Fire Protection Engineering course 20 

every year at Cal Poly. 21 

22 

PROFESSIONAL HIGHLIGHTS 23 

24 

Senior Consultant, Hughes Associates, Baltimore, MD, 2012‒present. Responsibilities 25 

include supervisory and managerial duties, project management, and consulting services to 26 

the commercial nuclear industry in the areas of safe shutdown analysis, fire modeling, 27 

probabilistic risk assessment, NFPA 805, and fire research. 28 

29 

Fire Protection Engineer, Science Applications International Corporation (SAIC), 30 

2001–2012. Responsibilities included project management and consulting services to the 31 

commercial nuclear industry in the areas of safe shutdown analysis, fire modeling, 32 

probabilistic risk assessment, NFPA 805, and fire research. Technical lead for the following 33 

Fire PRA studies in the United States: San Onofre Nuclear Generating Station, Kewaunee 34 

Power Station, VC Summer Power Station, and Nine Mile Point-1. Internationally, has 35 

offered consulting services in Brazil for the ANGRA Unit 1 Fire PRA. Project manager for 36 

the Nine Mile Point-1 and Prairie Island Fire PRAs. In addition, served as technical lead and 37 

project manager for numerous projects associated with fire modeling and fire risk analysis. 38 

Participated as a peer reviewer for four Fire PRAs. Member of the writing committees for the 39 

following commercial nuclear industry milestone projects: 40 

41  NUREG/CR-6850/EPRI 1011989, “EPRI/NRC–RES Fire PRA Methodology for Nuclear 

42 Power Facilities Volume 2 Detailed Methodology,” 2005. 

43  NUREG-1934/EPRI-1019195, “Nuclear Power Plant Fire Modeling Application Guide,” 

44 2012. 

45  NUREG-1824/ EPRI 1011999, “Verification and Validation of Selected Fire Models for 

46 Nuclear Power Plant Applications, Volume 1”. 2007. 
WG MEMBERS, NON-WG CONTRIBUTORS, AND FACILITATOR RESUMES 

A-5

Member of the ASME/ANS Fire PRA Standard writing committee, ASME/ANS RA-Sa-2009 1 

Standard for Probabilistic Risk Assessment for Nuclear Power Plant Applications. 2 

 3 

Author of the Reliability Engineering chapter of the Society of Fire Protection Engineers 4 

(SFPE) Handbook, the most widely used technical reference in the US fire protection 5 

community. Actively participates in the development of selected Fire PRA FAQ responses 6 

which are technical supplements to documented fire risk methods. Provides Fire Modeling 7 

and Fire PRA training through EPRI to Fire Protection and Fire PRA professionals in the 8 

nuclear industry. 9 

10 

SELECTED PUBLICATIONS AND PRESENTATIONS: 11 

12 

NUREG/CR-6850/EPRI 1011989, “EPRI/NRC–RES Fire PRA Methodology for Nuclear 13 

Power Facilities Volume 2 Detailed Methodology,” 2005. 14 

15 

NUREG-1934/EPRI-1019195, “Nuclear Power Plant Fire Modeling Application Guide,” 2012. 16 

17 

NUREG-1824/ EPRI 1011999, “Verification and Validation of Selected Fire Models for 18 

Nuclear Power Plant Applications, Volume 1,” 2007. 19 

20 

Joglar, F., “Reliability, Maintainability & Availability,” Section/Chapter 5-3, SFPE Handbook 21 

of Fire Protection Engineering, 4th Edition, DiNenno et al. (eds.), National Fire Protection 22 

Association, Quincy, MA, 2008, pp. 5-25–5-68. 23 

24 

EPRI TR-1002981, “Fire Modeling Guide for Nuclear Power Plant Applications,” 2002. 25 

26 

Presented conference papers in Probabilistic Safety Analysis (PSA) 2009, 2011, 2013, and 27 

Probabilistic Safety Analysis and Management (PSAM) 2010. 28 

29 
WG MEMBERS, NON-WG CONTRIBUTORS, AND FACILITATOR RESUMES 

A-6 

1 Ashley Mossa Lindeman, EPRI 

2 

3 EDUCATION 

4 

5 Worcester Polytechnic Institute May 2007 

6 Graduated with a Bachelor of Science in Mechanical Engineering with a concentration in 

7 thermal-fluids 

8 

9 Rensselaer Polytechnic Institute June 2010 

10 Graduated with a Master of Engineering in Mechanical Engineering 

11 

12 WORK EXPERIENCE

13 

14 Electric Power Research Institute May 2013-Present

15 Technical Leader / Project Manager, Risk & Safety Management (May 2013-Pres) 

16 

17 • Fire PRA research management: Manage projects to further advance the research 

18 within the area of fire probabilistic risk analysis for commercial nuclear power plants. 

19 Oversee projects in the area of fire events analysis, fire-induced circuit failure, fire 

20 modeling, fire damage consequences and fire model uncertainty. 

21 • Technical contributor to FPRA research: Participated in the classification of fire 

22 events for use in the calculation of fire ignition frequencies and non-suppression 

23 probability estimation. 

24 • Fire PRA Training Instructor: Instructed selected portions of the fire analysis module 

25 in the joint EPRI/NRC Fire PRA Training. 

26 • Member of the ASME/ANS Fire PRA standard writing committee 

27 

28 Westinghouse Electric Company June 2007-May 2013

29 Senior Engineer, Risk Applications and Methods II (July 2010-May 2013) 

30 

31 • Fire PRA model development using NUREG/CR-6850: Key individual in the fire PRA 

32 development including author or co-author on the following tasks: plant partitioning, 

33 fire ignition frequencies, zone of influence, fire scenario selection/scoping fire 

34 modeling, qualitative screening, quantitative screening and quantification. Provided 

35 peer review support for the utility during the industry peer review. 

36 • NFPA 805 Transition and Fire PRA for Fort Calhoun Station: Authored or co37 authored the following tasks in support of the Fire PRA project: plant partitioning, fire 

38 ignition frequencies, main control room habitability analysis, fire scenario selection, 

39 HRA and quantification. Provided peer review support for the utility during the 

40 industry peer review. Performed fire risk evaluations, supported the on-site NRC 

41 audit of the NFPA 805 transition, and responded to requests for additional 

42 information related to probabilistic risk assessment and fire modeling. 

43 • Technical lead for international fire PRA: Provided support from bid and proposal 

44 phase through project initiation on differences between US methodology and EdF 

45 specific methodology. Supported Fire PRA technical questions from a multi-national 

46 team located in four different time zones. 

47 • Industry Fire PRA Peer Review Experience: Participated in three domestic 

48 Pressurized Water Reactor Owner’s Group (PWROG) fire PRA peer reviews and 

49 one international fire PRA peer review. 
WG MEMBERS, NON-WG CONTRIBUTORS, AND FACILITATOR RESUMES 

A-7

1 • Project Manager Level 1: Satisfied classroom training and on the job training 

2 requirements of the Westinghouse Project Manager Development Program 

3 • Technical Leader Level 1: Satisfied requirements of the Technical Leader 

4 Development Program. 

5 

6 Engineer, Risk Applications and Methods II (June 2007-July 2010)

7 

8 • Performer for international PWR safe shutdown analysis: Primary tasks involved 

9 developing component list, tracing safe shutdown flowpaths, and supported 

10 execution of safe shutdown analysis using the Risk Spectrum software. Participated 

11 in walkdowns in support of both the fire and flood portions of the project. 

12 • Piloted draft EPRI/NRC Fire HRA Guidelines (NUREG-1921) for the PWROG: 

13 Participated in operator interviews and supported development of WCAP technical 

14 report. 

15 • Domestic fire PRA support: Performed on-site plant walkdowns, plant partitioning 

16 and fire ignition frequencies tasks. 

17 

18 PUBLICATIONS 

19 

20 • NUREG-2169 and EPRI 3002002936, Fire Ignition Frequencies and Non21 Suppression Probability Estimation Using the Updated Fire Events Database, 

22 November 2014. 

23 • OECD International Workshop on Fire PRA– Insights and Opportunities from the 

24 EPRI Updated Fire Events Database, April 2014. 
WG MEMBERS, NON-WG CONTRIBUTORS, AND FACILITATOR RESUMES 

A-8 

1 Nicholas Melly, NRC 

2 

3 EDUCATION 

4 

5 The University of Maryland – College Park, MD 

6 Bachelor of Science in Fire Protection Engineering, 2008 

7 

8 EXPERIENCE 

9 

10 U.S. Nuclear Regulatory Commission – Rockville, MD 7/2009-Present 

11 Fire Protection Engineer Office of Nuclear Regulatory Research 

12  Competed detailed circuit analysis and data processing of results for research projects 

13 which resulted in the publication of Electrical Cable Test Results and Analysis During 

14 Fire Exposure (ELECTRA-FIRE NUREG 2128) 

15  Managed DOE work related to the revision of NUREG/CR-6850, Integration of NFPA 

16 805 Frequently Asked Questions, Development of generic fire PRA methods, analyses 

17 related to fire PRA methods and Level 3 PRA Evaluation 

18  Instructed NUREG/CR-6850 Training related to Sections 2, 4, 5, 7, 14, and 15. 

19  Represented the NRC at International OECD Fire-Events Database and High-Energy 

20 Arching Fault Task Group Meetings 

21  Presented International research plans to NRC management 

22  Presented papers documenting NRC fire research findings at numerous technical 

23 conferences 

24 

25 Jacobs Engineering Group - Conshohocken, PA 1/2009-6/2009 

26 Fire Protection Engineer 

27  Designed a sprinkler system to be installed on a U.S. military facility chapel in Japan 

28  Designed a sprinkler system for a Pharmaceutical facility 

29  Designed wet pipe and dry pipe systems accounting for environmental conditions and 

30 freezer room applications 

31  Conducted probabilistic risk assessment and heat transfer analysis 

32  Evaluated protection of steel structural member s under high temperature exposure 

33 conditions 

34  Evaluated airflow simulations over essential pharmaceutical machinery to meet safety 

35 requirements 

36 

37 Triad Fire Protection - Springfield, PA 6/2008-12/2008 

38 Fire Protection Engineer 

39  Designed smoke detection systems and fire alarm systems 

40  Conducted research to identify the applicable design codes and standards for NPP 

41 applications 

42  Conducted hydraulic network analysis of sprinkler systems 

43 

44 SELECTED PUBLICATIONS 

45 

46  NUREG-2169, "Nuclear Power Plant Fire Ignition Frequency and Non-Suppression 

47 Probability Estimation Using the Updated Fire Events Database: United States Fire 

48 Event Experience Through 2009" 
WG MEMBERS, NON-WG CONTRIBUTORS, AND FACILITATOR RESUMES 

A-9

1  NUREG-2128, "Electrical Cable Test Results and Analysis During Fire Exposure 

2 (ELECTRA-FIRE), A Consolidation of Three Major Fire-Induced Circuit Cable Failure 

3 Experiments Performed Between 2001 and 2011 

4  Enhancements in the OECD FIRE Database - Fire Frequencies and Severity of Events, 

5 W. Werner, R. Bertrand, A. Huerta, J. S.Hyslop, N. Melly, and M. Rowekamp, 

6 Proceedings of SMiRT 21, 12th International Seminar on Fire Safety in Nuclear Power 

7 Plants and Installations, München, Germany 

8  Incorporation of NFPA-805 Internal Fire Scenarios into SPAR all Hazard Models S. 

9 Sancaktar, F. Ferrante, N. Melly U.S. Nuclear Regulatory Commission, Washington DC, 

10 USA 20555-0001, 2011 

11  OECD FIRE Database Applications and Challenges -A Recent Perspective, Marina 

12 Roewekamp, Matti Lehto, Heinz-Peter Berg, Nicholas Melly, Wolfgang Werner Paper 

13 presented at OECD/NEA/CSNI/WGRISK International Workshop on Fire PRA, Garching, 

14 Germany 

15  Expert Judgment: An Application in Fire-Induced Circuit Analysis, Gabriel Taylor P.E., 

16 Nicholas Melly, Tammie Pennywell, Paper presented at OECD/NEA/CSNI/WGRISK 

17 International Workshop on Fire PRA, Garching, Germany 

18 

19 

20 
WG MEMBERS, NON-WG CONTRIBUTORS, AND FACILITATOR RESUMES 

A-10 

1 David Miskiewicz, Engineering Planning & Management, Inc. 

2 

3 EDUCATION 

4 

5 1975–1979 B.S., Nuclear Engineering, Pennsylvania State University, State College, PA 

6 

7 Summary 

8 

9 Nuclear engineer with over 30 years of experience working in the nuclear power industry. 

10 Currently Mr. Miskiewicz is managing the Risk Services Division for EPM. David has been a 

11 practicing PRA engineer for more than 20 years with extensive industry involvement including 

12 leading, presenting and instructional roles, and is a recognized expert in PRA. He has additional 

13 experience with software development and systems and design engineering activities including 

14 work related to reactor internals and reactor vessel integrity. 

15 

16 EXPERIENCE 

17 

18 2012–Present EPM, Inc., Raleigh, NC 

19 

20  Manage operations and personnel within the Risk Services Division of EPM. 

21  Project manager and technical lead for development of Robinson Fire PRA to support 

22 NFPA-805. 

23  Project oversight and consulting support for completion of Point Beach Fire PRA and LAR 

24 preparation to support NFPA-805 transition. 

25  Member NEI 805 Task Force and Fire PRA Task Force 

26  Member of ASME CNRM Subcommittee on Model Maintenance, Special Committee on 

27 Inquiries, and the Part 4 (Fire PRA Standards) writing team 

28  Participant in various EPRI/NRC MOU projects 

29 

30 2005–2012 Progress Energy, Raleigh, NC 

31 

32  Support the Progress Energy Fleet of Nuclear Plants. Responsibilities include maintaining 

33 PSA models, performing PSA applications, and responding to emergent plant issues. 

34  Project management and technical lead for development of fire PRAs to support transition 

35 of the Progress Energy fleet to NFPA-805. 

36  Software owner for PSA software used at Progress Energy. Upgraded and completed in37 house SQA for the latest versions of EPRI R&R software in 2006. 

38  Participated in Limerick Peer Review against the ASME Standard 

39  Member NEI 805 Task Force and Fire PRA Task Force 

40  Member of ASME CNRM Subcommittee on Technology, Special Committee on Inquiries, 

41 and the Fire PRA Standards writing team 

42  Participant in various EPRI/NRC MOU projects 

43 

44 

45 2001–2005 Progress Energy, Crystal River, FL 

46 

47  Support the Progress Energy Fleet of Nuclear Plants 

48  Primary responsible individual for CR3 PRA models and applications. Extensive interface 

49 experience with plant engineering, operations, work controls, and licensing groups. 
WG MEMBERS, NON-WG CONTRIBUTORS, AND FACILITATOR RESUMES 

A-11

1  Applications performed include 14day Emergency Diesel AOT extension, One time AOT 

2 extensions for Service water, Chilled water, Emergency Diesels, Emergency Feedwater, 

3 and ILRT extensions for several plants. 

4  Experienced with product development and regulatory interface related to the Significance 

5 Determination Process [19]. 

6  Chairman of B&W Owners Group Risk Applications Committee 

7  Member NEI Risk Applications Task Force 

8  Member ASME PSA Standard Addendum B writing team 

9  Participated in 3 external NEI PSA Peer Certification Teams. 

10  Developed Tool and database for reviewing PRAs against the ASME Standard which was 

11 a prototype for the ePSA module offered by EPRI. 

12 

13 1987–2001 Florida Power Corporation, Crystal River, FL 

14 

15  Responsible for the CR3 PRA model and applications 

16  Completed extensive models updates resulting from CR3 1.5 year design outage. 

17  Temporarily served as the Maintenance Rule Supervisor responsible for setting up CR3 

18 expert panel and preparing for baseline 10CFR50.65 inspection. Also, served as 

19 Chairman of Maintenance Rule Expert Panel for several years. 

20  Member of B&W Owners Group Risk Applications Committee 

21  Involved in the preparation and submittal of IPE and IPEEE for Crystal River unit 3. 

22  Developed various in-house software applications which significantly increased the 

23 efficiency of certain aspect of PSA analysis. These included and online risk monitoring at 

24 CR3 (pre-EOOS), a plant specific data management tool, a fire scenario evaluation tool, 

25 HRA and maintenance unavailability calculators, a level 2 bridge tree tool, and a 

26 component risk ranking tool. 

27 

28 1983–1998 Florida Power Corporation, Crystal River, FL & St. Petersburg, FL 

29 

30  Chairman and/or member of B&W Owners Group Materials Committee and Reactor 

31 Vessel Working Group respectively from 1986-1998. 

32  Technical lead for development of LTOP technical specifications for CR3. Also responsible 

33 for implementation of PLTR and management of the reactor vessel surveillance program 

34 at CR3. 

35  Engineer in Mechanical Design group responsible for plant modifications including 

36 replacement of reactor vessel internals bolting and HPI nozzle safe ends. 

37 

38 1979–1983 Gilbert/Commonwealth, Inc., Reading, PA 

39 

40  Field engineer working as consultant/contractor for nuclear utilities. Primary field was 

41 radioactive waste system upgrades. 

42  Design engineer in the radwaste management section. Participated in radwaste 

43 reduction, spent fuel storage and decommissioning projects. 
WG MEMBERS, NON-WG CONTRIBUTORS, AND FACILITATOR RESUMES 

A-12 

1 Steven Nowlen, Consultant 

2 

3 Retired from SNL in June 2014 

4 

5 EDUCATION AND HONORS 

6 

7 Appointed to the rank of Distinguished Member of the Technical Staff at Sandia National 

8 Laboratories, October 2001, an honor reserved for no more than 10% of the SNL 

9 engineering/science staff. 

10 Master of Science, Mechanical Engineering, Michigan State University, East Lansing Michigan, 

11 March 1984. 

12 DuPont Research Fellow, Department of Mechanical Engineering, Michigan State University, 

13 1981-1983 

14 Bachelor of Science with High Honor, Mechanical Engineering, Michigan State University, East 

15 Lansing Michigan, December 1980, Graduated Phi Beta Kappa 

16 

17 PROFESSIONAL EXPERIENCE 

18 

19 Since joining Sandia in 1983, I have been active in both experimental and analytical research in 

20 the fields of nuclear power plant safety with a focus on fire safety and quantitative fire risk 

21 analysis. I have been Sandia’s technical and programmatic lead for the nuclear power fire 

22 research programs since 1987. My responsibilities include direct technical contributions, 

23 technical team leadership, sponsor interactions, program planning and program management. 

24 The most important application of my research has been in the development and application of 

25 probabilistic risk assessment (PRA) methods for fires in nuclear power plants; that is, 

26 quantitative assessments of the impact of fires on nuclear power plant safety and operations. I 

27 also have experience in harsh environment equipment qualification testing and accelerated 

28 thermal and radiation aging of materials. 

29 My experimental work has included the planning, execution, evaluation, and reporting of fire 

30 safety experiments, as well as the interpretation, evaluation, and application of experimental 

31 results generated by other researchers. Specifically, I have experience in the testing of fire 

32 growth behavior, large-scale room fires, enclosure ventilation and smoke purging, cable and 

33 electrical equipment fire-induced damage, smoke particulate characterization, fire barriers, 

34 smoke damage effects on digital equipment, and cable ampacity and ampacity derating. 

35 As a secondary aspect of my experimental experience, I have also participated in Equipment 

36 Qualification tests assessing the performance of electrical equipment in the harsh steam and 

37 radiation environments associated with nuclear power plant severe accidents. This work has 

38 included both accelerated thermal and radiation aging of electrical cables and the evaluation of 

39 equipment performance during harsh environmental exposures such as loss of coolant 

40 accidents. 

41 Related analytical efforts in the area of fire safety have included the evaluation and validation of 

42 computer fire simulation models, the review and analysis of actual fire events in nuclear power 

43 plants, fire risk assessment analytical support work, the development and evaluation of fire risk 

44 assessment methods, and the development and evaluation of analytical methods for cable 

45 ampacity and fire barrier ampacity derating assessments. I have also participated as an expert 

46 consultant in various inspection activities for U.S. Nuclear Regulatory Commission (NRC). 

47 I have performed training for the NRC staff in the application of the NRC Significance 

48 Determination Process (SDP) for fire protection inspection findings. I am currently participating 
WG MEMBERS, NON-WG CONTRIBUTORS, AND FACILITATOR RESUMES 

A-13

1 in an effort to develop and deploy inspector training for application to those NRC licensees 

2 transitioning to the new risk-informed, performance-based fire protection requirements. I also 

3 act as technical coordinator and classroom instructor for the annual Fire PRA training course 

4 offered as a part the NRC Office of Nuclear Reactor Research (RES) and Electric Power 

5 Research Institute (EPRI) collaboration on fire research. This training course has been 

6 conducted annually since 2005 and routinely attracts well over 100 participants per year. 

7 I was a member of the U.S. NRC Senior Review Board for the review of Individual Plant 

8 Examination for External Events (IPEEE). I am currently a member of the ASME/ANS Joint 

9 Committee on Nuclear Risk Management Subcommittee on Standard Maintenance. I also co10 chair the associated working group on fire risk. 

11 My publication list is available on request and includes 10 journal articles, approximately 30 

12 formal SNL technical reports, five invited conference papers and over 20 other general 

13 conference papers. I also co-authored a section of the SFPE Handbook of Fire Protection 

14 Engineering entitled “Risk Assessment for Nuclear Power Plants.” 

15 

16 Notable Roles and Accomplishments 

17 

18 SNL technical area lead and program manager for nuclear power plant related fire research 

19 (1987-present) 

20 Voting member of the American Society of Mechanical Engineers (ASME) American Nuclear 

21 Society (ANS) Joint Committee for Nuclear Risk Management (JCNRM) Subcommittee on 

22 Standards Maintenance 

23 Co-Chair of the ASME/JCNRM Standard for Level 1 / Large Early Release Frequency 

24 Probabilistic Risk Assessment for Nuclear Power Plant Applications Fire Working Group (RA25 Sa-2009) 

26 Leading member of the core writing team for the American Nuclear Society (ANS) Standard on 

27 Fire PRA methodology (ANSI/ANS-58.23-2007) 

28 Lead author and NRC technical team lead for the consensus Fire PRA methodology 

29 NUREG/CR-6850 which was developed as a collaboration between the NRC and the Electric 

30 Power Research Institute (EPRI)) 

31 Technical Coordinator for development of the U.S. NRC Significance Determination Process 

32 (SDP) for risk-informed fire inspections (2003-2004) 

33 Technical coordinator and instructor for the annual NRC/EPRI Fire PRA methodology training 

34 sessions (2004-present) 

35 Member of the Nuclear Regulatory Commission (NRC’s) Senior Review Board for the review 

36 and evaluation of licensee submittals under the Individual Plant Evaluation of External Events 

37 Program (1995-2001) 

38 Technical advisor to the U.S. NRC staff during development of the National Fire Protection 

39 Association (NFPA) Performance-Standard for Fire Protection for Light Water Nuclear Reactor 

40 Electric Generating Plants (NFPA 805) (1995-2001) 

41 Qualified as an expert witness in nuclear power plant fire safety in U.S. Federal Criminal District 

42 Court (1995) 

43 
WG MEMBERS, NON-WG CONTRIBUTORS, AND FACILITATOR RESUMES 

A-14 

Victor Ontiveros1 1 , Jensen Hughes 2 

EDUCATION 3 

4 

Ph.D., Reliability Engineering, University of Maryland, 2013 5 

M.S., Fire Protection Engineering, University of Maryland, 2010 6 

B.S., Fire Protection Engineering, University of Maryland, 2007 7 

A.A., General Studies, Montgomery College, 2004 8 

9 Victor Ontiveros, PhD, is a recent graduate from the University of Maryland with degrees in Fire 

10 Protection and Reliability Engineering. During his studies, Dr. Ontiveros spent considerable time 

11 working on model development and uncertainty quantification. Dr. Ontiveros has extensive 

12 laboratory experience including material fatigue testing and laboratory setup and organization. He 

13 has experience performing Occupational Safety and Health inspections in spaces ranging from 

14 office space to machine shops and outdoor spaces. He has provided support in fire PRA projects 

15 at Prairie Island and Monticello Nuclear Generating Plants. 

16 PROFESSIONAL HIGHLIGHTS

17 Engineer II, Hughes Associates, Baltimore, MD, present. Responsibilities include fire analysis 

18 scenario analysis, fire modeling, plant walkdowns, and fire probabilistic risk assessment. 

19 Graduate Research Intern, Dept. of Mechanical Engineering, University of Maryland, 

20 College Park, MD, 2008–2014. Organized and set up Department of Mechanical Engineering 

21 Mechanics and Reliability Lab. Worked with Campus Facilities to ensure requirements for 

22 laboratory space were met. Administered retrofitting of load frames. Instructed and assisted 

23 fellow students in laboratory capabilities and experimental testing. Planned and researched for 

24 Ph.D. dissertation: developed and implemented accelerated fatigue experiments of aluminum 

25 alloys; and developed strain energy expended and thermodynamic entropy based models for 

26 determination of life expended. For master’s thesis: accounted for uncertainty for sub-models 

27 used within fire simulation codes; updated state of knowledge using Bayesian methodology; and 

28 determined 'real' parameter values given uncertain model predictions and experimental 

29 measurements. 

AWARDS 30 

31 

Recipient, Montgomery Scholar at Montgomery College Rockville, two-year tuition and 32 

summer study at Cambridge University, England, Summer 2003; Beacon Conference 33 

finalist in Technology and Technological Studies, 2004 34 

Recipient, Alfred P. Sloan Foundation Minority Ph.D. Program in Mathematics, 2011–2012 35 

Recipient, Willie M. Webb Reliability Engineering Fellowship, 2012–2013 36 

37 PUBLICATIONS AND PRESENTATIONS 

38 Ontiveros, V., “Strain Energy and Thermodynamic Entropy as Prognostic Measures of Crack 

39 Initiation in Aluminum Alloys,” Ph.D. Dissertation, University of Maryland, College Park, MD, 

40 January 2014.

 

1

 Not a working group member. 
WG MEMBERS, NON-WG CONTRIBUTORS, AND FACILITATOR RESUMES 

A-15

1 Zhu, S.P., Huang, H.Z., Ontiveros, V., He, L.P., and Modarres, M., “Probabilistic Low Cycle 

2 Fatigue Prediction Using Energy-based Damage Parameter and Accounting for Model 

3 Uncertainty,” Int. J. Damg, Mech., 21, December 2011, pp. 1128–1153. 

4 Zhu, S.P., Huang, H.Z., Ontiveros, V., He, L.P., and Modarres, M., “Probabilistic Life Prediction 

5 for High Temperature Low Cycle Fatigue Using Energy-Based Damage Parameter and 

6 Accounting for Model Uncertainty,” IDETC/CIE2001, Washington DC, August 28–31, 2011, pp. 

7 435–443. 

Smith, R., Ontiveros, V., Paradee, G., Modarres, M., and Hoffman, P., “Probabilistic Strain 8 

Energy Life Assessment Model,” ICM11, Milano, Italy, June 5–9, 2011. 9 

10 Ontiveros, V. and Modarres, M., “An Integrated Methodology for Assessing Model 

11 Uncertainty in Fire Simulation Codes,” PSA, Wilmington, NC, March 13–17, 2011. 

12 Ontiveros, V., Cartillier, A., and Modarres, M., “An Integrated Methodology for Assessing 

13 Fire Simulation Codes,” Nuc. Sci. Eng., 166, November 2010, pp. 179–201. 

14 Ontiveros, V., “An Integrated Methodology for Assessing Fire Simulation Code Uncertainty,” 

15 Master Thesis, University of Maryland, College Park, MD, April 2010. 

16 Ontiveros, V., Cartillier, A., Le Gac, C., and Modarres, M., "A Probabilistic Framework for 

17 Model Uncertainty in Fire Simulation Codes," Risk Management for Tomorrow’s Challenges 

18 (RM4TC), Washington, DC, November 15–19, 2009. 

19 Azarkhail, M., Ontiveros, V., and Modarres, M., “A Bayesian Framework for Model 

20 Uncertainty Considerations in Fire Simulation Codes,” International Conference on Nuclear 

21 Engineering (ICONE 17), Brussels, Belgium, July 12–16, 2008, pp. 639–648. 

22 

23 
WG MEMBERS, NON-WG CONTRIBUTORS, AND FACILITATOR RESUMES 

A-16 

1 David Stroup, NRC 

2 

3 EDUCATION 

4 

5 The University of Maryland – College Park, MD 

6 Masters of Science in Mechanical Engineering, 1987 

7 The University of Maryland – College Park, MD 

8 Bachelor of Science in Fire Protection Engineering, 1981 

9 Montgomery College – Rockville, MD 

10 Associate of Arts in Fire Science, 1977 

11 

12 Registered Professional Engineer 

13 Delaware, License No. 7996 

14 Maryland, License No. 20052 

15 

16 EXPERIENCE 

17 

18 U.S. Nuclear Regulatory Commission – Rockville, MD 2/2011-Present

19 Senior Fire Protection Engineer Office of Nuclear Regulatory Research 

20 • Develop and implement research projects to identify emerging technical issues in fire 

21 phenomena, fire modeling, and fire probabilistic risk assessment (PRA) 

22 • Prepare or review fire modeling, fire PRA, and fire research reports 

23 • Participate in the planning, formulation, and implementation of agency programs, 

24 policies, and procedures 

25 • Provide oral and written communications on complex technical fire protection subjects to 

26 a wide variety of audiences 

27 

28 U.S. Nuclear Regulatory Commission – Rockville, MD 1/2008–1/2011 

29 Fire Protection Engineer Office of Nuclear Regulatory Research 

30 • Implemented research projects to identify emerging technical issues in fire phenomena, 

31 fire modeling, and fire probabilistic risk assessment (PRA) 

32 • Prepared or reviewed fire modeling, fire PRA, and fire research reports 

33 

34 National Institute of Standards& Technology – Gaithersburg, MD 12/1995-1/2008 

35 Research Fire Prevention Engineer Building and Fire Research Laboratory 

36 • Conducted research and other investigative work on prediction of fire hazard 

37 development, fire risk evaluation, performance design and acceptance, evacuation 

38 analysis, performance of materials, and fire model development 

39 • Performed research in the application of the empirical laws of thermodynamics and in 

40 heat conduction and mass diffusion in two and three dimensions 

41 • Served as a peer reviewer for several performance-based design projects and technical 

42 guidance documents 

43 

44 U.S. General Services Administration – Washington, DC 11/1989–12/1995 

45 Fire Protection Engineer Public Buildings Service 

46 • Developed and evaluated GSA fire protection engineering practices 

47 • Served as official GSA representative to other public and private organizations 

48 concerned with fire protection 
WG MEMBERS, NON-WG CONTRIBUTORS, AND FACILITATOR RESUMES 

A-17

1 • Provided guidance to GSA regional personnel, other Services, and Staff Offices 

2 regarding the selection, procurement, and use of fire protection equipment and 

3 construction techniques 

4 

5 Montgomery College –Rockville, MD 1/1990–6/1990

6 Instructor, Part-time Department of Engineering, Physical and Computer Sciences 

7 

8 Schirmer Engineering Corporation – Falls Church, VA 7/1989–11/1989

9 Fire Protection Engineer 

10 • Evaluated proposed and existing buildings and other structures for compliance with 

11 various building and fire codes 

12 • Developed alternative strategies for achieving fire safety levels equivalent to those 

13 specified in recognized fire and building codes 

14 

15 National Institute of Standards& Technology – Gaithersburg, MD 6/1981–7/1989 

16 Research Fire Prevention Engineer Building and Fire Research Laboratory 

17 • Performed theoretical and experimental research on fire build-up in compartments 

18 including planning and interpretation of experiments (bench scale and full scale), 

19 translation to usable form, data reduction, analysis, and presentation of results 

20 • Performed experiments and analysis of data to construct computational models of fire 

21 growth and suppression 

22 

23 National Institute of Standards& Technology – Gaithersburg, MD 11/1980–6/1981

24 Fire Prevention Engineering Technician Center for Fire Research 

25 

26 SELECTED PUBLICATIONS 

27 

28 • NUREG-1805, Supplement 1, Volumes 1 and 2, Fire Dynamics Tools (FDTs) 

29 Quantitative Fire Hazard Analysis Methods for the Nuclear Regulatory Commission Fire 

30 Protection Inspection Program, July 2013. 

31 • NUREG-1824, Supplement 1/EPRI 3002002182, Verification and Validation of Select 

32 Fire Models for Nuclear Power Plant Applications, Draft for Public Comment, December 

33 2014. 

34 • NUREG-1934/EPRI 1023259, Nuclear Power Plant Fire Modeling Analysis Guidelines 

35 (NPP FIRE MAG), November 2012. 

36 • NUREG-2122, Glossary of Risk-Related Terms in Support of Risk-Informed 

37 Decisionmaking, November 2013. 

• “Flammability Hazards of Materials”, (Co-author), Fire Protection Handbook, 20th 38 edition, 

39 Chapter 2, Section 2.3, National Fire Protection Association, 2008. 

40 

41 ACHIEVEMENTS 

42 

43 Salamander - Fire Protection Engineering Honor Society 

44 General Services Administration Federal Engineer of the Year, 1995 

45 Fellow – Society of Fire Protection Engineers, 2006 

46 U.S. Department of Commerce Bronze Metal, 2007 

47 Nuclear Regulatory Commission Federal Engineer of the Year, 2014 

48 Member, SFPE Standards-Making Committee on Design Fire Scenarios 

49 Society Memberships: Society of Fire Protection Engineers, National Fire Protection 

50 Association, American Nuclear Society, and International Association of Fire Safety Science
WG MEMBERS, NON-WG CONTRIBUTORS, AND FACILITATOR RESUMES 

A-18 

Mano Subudhi2 1 , BNL 

2 

3 EDUCATION 

4 

5 1969 - B.S., Mechanical Engineering, Banaras Hindu University, India 

6 1970 - M.S., Mechanical Engineering, Massachusetts Institute of Technology 

7 1974 - Ph.D., Mechanical Engineering, Polytechnic Institute of New York 

8 

9 EXPERIENCE 

10 

11 1976-Present 

12 Brookhaven National Laboratory, Over his career at BNL, Dr. Subudhi developed statistical 

13 methods for characterizing degradation within various components (NUREG/CR-6869). He also 

14 studied geomagnetic effects on nuclear facilities (NUREG/CR-5990), laboratory testing of 

15 electrical components (NUREG/CR-5280), and developed recommendations to improve current 

16 maintenance practices (NUREG/CR-5812). He also performed loss of coolant accident (LOCA) 

17 testing of Cables used in NPPs (NUREG/CR-6384) and did a configuration management study 

18 of radiological facilities. He participated in an International Atomic Energy Agency (IAEA) 

19 neutron monitoring experiment and a safeguard assessment of a US DOE facility, Portsmouth 

20 Gas Diffusion Plant in Ohio, for down-blending operation of highly-enriched uranium (HEU) from 

21 FSU countries to low-enriched uranium (LEU). 

22 

23 Dr. Subudhi is very conversant with all Subsections of the ASME Boiler and Pressure Vessel 

24 (B&PV) Code, Section III on Nuclear Power Plant Components; with IEEE Std. 323 on 

25 environmental qualification, with IEEE Std. 383 on cable qualification, and with IEEE Std. 344 

26 on seismic qualification. He has served in working groups of these ASME and IEEE standards 

27 committees to develop various standards and guidance documents. Recently, he began work 

28 on the National Fire Protection Association (NFPA) Standard 805 requirements for fire 

29 probabilistic risk assessments (PRAs), using a risk-informed performance-based approach.

30 

31 1975-1976 

32 Bechtel Power Corp., Mechanical Engineer. Involved in the stress analysis of nuclear power 

33 plant components subjected to thermal, dead weight, seismic, thermal transients, pressure and 

34 fatigue loads; special problems including water hammer, flow-induced vibrations, and sudden 

35 valve closures; and preparation of Nuclear Class I Reports for licensing purpose. Represented 

36 Bechtel in interfacing manufacturers, clients and vendors. 

37 

38 SELECTED PUBLICATIONS 

39 

40 "Seismic Analysis of Piping Systems Subjected to Independent Support Excitations by Using 

41 Response Spectrum and Time History Methods," BNL Technical Report No. BNL-NUREG42 31296, April 1982. Also, Presented at the ASME Summer PVP Conference, Portland, Oregon, 

43 PVP-Vol. 73, June 1983. 

44 

45 "The Assessment of Alternate Procedures for the Seismic Analysis of Multiply Supported Piping 

46 Systems," Proceedings of the 1985 ASME PVP Conference, New Orleans, PVP-Vol. 98.3, June 

47 1985. 

48 

 

2

 Moderator/facilitator for the working group 
WG MEMBERS, NON-WG CONTRIBUTORS, AND FACILITATOR RESUMES 

A-19

1 "Seismic Upgrading of the Brookhaven High Flux Beam Research Reactor," Proceedings of 

2 DOE Natural Phenomena Hazards Mitigation Conference, Las Vegas, October 1985. 

3 

4 "Improving Motor Reliability in Nuclear Power Plants," NUREG/CR-4939, BNL-NUREG-52031, 

5 Vols. 1, 2, 3, November 1987. 

6 

7 "Age-Related Degradation of Westinghouse 480-Volt Circuit Breaker," NUREG/CR-5280, BNL8 NUREG-52178, Vols. 1&2, November 1990. 

9 

10 "Degradation Modeling with Application to Aging and Maintenance Effectiveness Evaluations," 

11 (Co-author), NUREG/CR-5612, BNL-NUREG-52252, March 1991. 

12 

13 "Life Testing of a Low Voltage Air Circuit Breaker to Assess Age-Related Degradation", Nuclear 

14 Technology, Vol. 97, pp.362-370, March 1992. 

15 

16 “Managing Aging in Nuclear Power Plants: Insights from NRC’s Maintenance Team Inspection 

17 Reports,” Nuclear Safety, Vol. 35, No. 1, January-June 1994. 

18 

19 “RAPTOR Gas Gun Testing Experiment,” (Co-author) Proprietary, CRADA BNL-C-96-01, June 

20 1998. 

21 

22 “A Reliability Physics Model for Aging of Cable Insulation Materials,” NUREG/CR-6869, BNL23 NUREG-73676-2005, March 2005. 

24 

25 “Application of laser generated ultrasonic pulses in diagnostics of residual stresses in welds,” 

26 Proc. of SPIE, 2005. 

27 

28 “Expert Panel Report on Proactive Material Degradation Assessment,” NUREG/CR-6923, BNL29 NUREG-77111-2006, February 2007. 

30 

31 “Joint Assessment of Cable Damage and Quantification of Effects from Fire (JACQUE-FIRE): 

32 Volume 1 – Phenomena Identification and Ranking Table (PIRT) Exercise for Nuclear Power 

33 Plant Fire-Induced Electrical Circuit Failure,” NUREG/CR-7150, Vol. 1, BNL-NUREG-98204-

34 2012, EPRI 1026424, October 2012. 

35 

36 “Joint Assessment of Cable Damage and Quantification of Effects from Fire (JACQUE-FIRE): 

37 Volume 2 – Expert Elicitation Exercise for Nuclear Power Plant Fire-Induced Electrical Circuit 

38 Failure,” NUREG/CR-7150, Vol. 2, BNL-NUREG-98204-2012, EPRI 3002001989, May 2014. 

39 
WG MEMBERS, NON-WG CONTRIBUTORS, AND FACILITATOR RESUMES 

A-20 

1 Gabriel Taylor, NRC 

2 

3 EDUCATION 

4 

5 Masters of Science in Fire Protection Engineering, May 2012 

6 Bachelor of Science in Electrical Engineering, December 2004 

7 

8 Registered Professional Engineer 

9 Maryland, Fire Protection, 2013 

10 

11 EXPERIENCE 

12 

13 U.S. Nuclear Regulatory Commission - Rockville, MD August 2013- Present Senior Fire 

14 Protection Engineer 

15  Evaluated the effectiveness of aspirated smoke detection systems for use in NPP fire 

16 PRA applications 

17  Instructed NUREG/CR-6850 training related to fire-induced circuit failure probability 

18 estimation 

19  Supported Development of Post-Fire Safe Shutdown Training for Regional Inspectors 

20  Chaired IEEE P1848, Co-chaired IEEE 1202 

21 U.S. Nuclear Regulatory Commission - Rockville, MD October 2007- August 2013 

22 Fire Protection Engineer 

23 

24  Expert Member of the Probabilistic Risk Assessment (PRA) expert elicitation on fire25 induced cable damage spurious operation probability 

26  Expert Member of the Phenomena Identification and Ranking Table (PIRT) exercise on 

27 Nuclear Power Plant Fire-Induced Electrical Circuit Failure 

28  Instructed NUREG/CR-6850 training related to fire-induced circuit failure probability 

29 estimation 

30  Witnessed fire tests, analyzed results and wrote test reports on Duke Armored cable 

31 testing, Navy Digital I&C testing, Progress Penetration Seal Testing. 

32  International OECD Fire-Events Database and High Energy Arching Fault Task Group 

33  Managed DOE work on fire-induced failure circuit testing and conducted supplementary 

34 data analysis (DESIREE-FIRE, KATE-FIRE) 

35  Presented research at numerous conferences and to the Advisory Committee on 

36 Reactor Safeguards (ACRS) 

37 U.S. Nuclear Regulatory Commission - Rockville, MD April 2005 - October 2007 

38 NSPDP General Engineer 

39  Graduate of NSPDP Class of 2007 

40  DORL: Evaluated proposed changes to license amendments in regards to their effect to 

41 public safety 
WG MEMBERS, NON-WG CONTRIBUTORS, AND FACILITATOR RESUMES 

A-21

1  ACRS: Prepared summary report for committee members and assisted with meeting 

2 preparations 

3  RII/Watts Bar Resident Office: Became basic inspector qualified IMC 1245 Appendix A 

4 The Pennsylvania State University - University Park, PA August 2003 - February 2004 

5 Undergraduate Research Assistant, Dr. P. M. Lenahan 

6  Modified magnet power supply to operate correctly using U.S. power system 

7  Designed data acquisition system to signal average ESR and SDR signals using 

8 LabVIEW 7 

9  Reviewed, ordered, and installed SDR spectroscopy system 

10 OSRAM Sylvania Inc. - St. Marys, PA January - March 2005 & January- August 2003 

11 Process Engineer & Engineering Co-Op (R&D, Process, EH&S, Electrical Departments)

12  Developed and conducted tests to examine customer complaints and analyzed the 

13 safety of products 

14  Developed a recycling program to reduce net residual waste and increase gain from 

15 recyclable goods 

16  PLC programming using VersaPro for GE PLC's (Latter-logic) 

17  Designed and constructed electrical cabinet using AutoCAD (ergonomic layout for 

18 operator and maintenance) 

19 

20 ACHIEVEMENTS 

21 Nuclear Regulatory Commission Federal Engineer of the Year, 2015 

22 Member of NSPE 

23 Member of IEEE, PES, ICC 

24 Member of NFPA 

25 Eagle Scout - Troup #95, Bucktail Council 

26 Eta Kappa Nu (HKN) - Epsilon Chapter - National Electrical/Computer Engineering Honors 

27 Society 

28 Dale Carnegie Program Graduate 

29 Penn State Conservation Leadership School Graduate 

30 Rivers Conservation Leadership School Graduate 

31 

32 PUBLICATIONS 

33 Subudhi, M., Martinez-Guridi, G., Taylor, G., et. al., NUREG/CR-7150, Volume 2, "Joint 

34 Assessment of Cable Damage and Quantification of Effects from Fire (JACQUE-FIRE), Expert 

35 Elicitation Exercise for Nuclear Power Plant Fire-Induced Electrical Circuit Failure," U.S. NRC, 

36 Washington, DC, 2014. 

37 

38 Taylor, G., Melly, N.B., Pennywell, T., "Expert Judgment, An Application in Fire-Induced Circuit 

39 Analysis," International Workshop on Fire PRA, OECD/NEA Committee on the Safety of Nuclear 

40 Installations, Garching, Germany, April 2014. 

41 

42 Melly, N.B., Taylor, G., Stroup, D.W., "U.S. NRC Fire Safety Research Activities," International 

43 Workshop on Fire PRA, OECD/NEA Committee on the Safety of Nuclear Installations, 

44 Garching, Germany, April 2014. 
WG MEMBERS, NON-WG CONTRIBUTORS, AND FACILITATOR RESUMES 

A-22 

1 

2 Taylor, G., Gallucci, R.H.V., Subudhi, M., Martinez-Guiridi, G., "Fire PRA Advancements in 

3 Estimating the Likelihood of Fire-Induced Spurious Operations," American Nuclear Society, PSA 

4 2013, International Topical Meeting on Probabilistic Safety Assessment Analysis, Columbia, SC, 

5 September 2013. 

6 

7 Taylor, G., Melly, N., Woods, H., Pennywell, T., Olivier, T., Lopez, C., NUREG-2128, "Electrical 

8 Cable Test Results and Analysis During Fire Exposure (ELECTRA-FIRE), A Consolidation of 

9 Three Major Fire-Induced Circuit and Cable Failure Experiments Performed Between 2001 and 

10 2011," U.S. NRC, Washington, DC, 2013. 

11 

12 Subudhi, M., Higgins, J., Taylor, G.J., et.al., NUREG/CR-7150, Volume 1, "Joint Assessment of 

13 Cable Damage and Quantification of Effects from Fire (JACQUE-FIRE), Phenomena 

14 Identification and Ranking Table (PIRT) Exercise for Nuclear Power Plant Fire-Induced 

15 Electrical Circuit Failure," U.S. NRC, Washington, DC, 2012. 

16 

17 Taylor, G., "Evaluation of Critical Nuclear Power Plant Electrical Cable Response to Severe 

18 Thermal Fire Conditions," Masters of Science Thesis, Graduate School of the University of 

19 Maryland, College Park, MD 2012. 

20 

21 Taylor, G., Barrett, H., Funk, D., Nowlen, S., "Advances in Understanding the Phenomena of 

22 Electrical Cable Fire-Induced Hot Shorting," American Nuclear Society, Annual Meeting, June 

23 2011. 

24 

25 Nowlen, S.P., Brown, J.W., Taylor, G.J., "Electrical Failure Behavior of Kerite® FR Insulated 

26 Electrical Cables," American Nuclear Society, Annual Meeting, June 2011. 

27 

28 Taylor, G., Salley, M.H., NUREG-1924, "Electrical Raceway Fire Barrier Systems in U.S. 

29 Nuclear Power Plants," U.S. NRC, Washington, DC, 2010. 

30 

31 Taylor, G., McGrattan, K., Nowlen, S.P., "Electrical Circuit and Cable Testing," Interflam 2010, 

32 12th International Fire Science and Engineering Conference, University of Nottingham, UK, July 

33 2010. 

34 

35 Taylor, G., Nowlen, S.P., Brown, J.W., "Direct Current Electrical Shoring in Response to 

36 Exposure Fire - The DESIREE-FIRE Project," 20th International Conference on Structural 

37 Mechanics in Reactor Technology (SMIRT 20) - 11th International Post-Conference Seminar on 

38 Fire Safety in Nuclear Power Plants and Installations," Espoo Finland, August 2009. 

39 

40 Taylor, G., Salley, M.H., "10 Rules of Fire Induced Cable Failure," National Institute of 

41 Standards and Technology, Annual Conference on Fire Research, Gaithersburg, MD, 2008. 

42 

43 

44 

45 
WG MEMBERS, NON-WG CONTRIBUTORS, AND FACILITATOR RESUMES 

A-23

Justin Williamson3 1 , Jensen Hughes 

2 

3 EDUCATION

4 

Ph.D., Mechanical Engineering, University of Maryland, 2009 5 

M.S., Fire Protection Engineering, University of Maryland, 2004 6 

B.S., Fire Protection Engineering, University of Maryland, 2001 7 

8 

9 Justin Williamson, PhD, is a Fire Protection Engineer with six years’ experience. He has 

10 extensive experience in fire, smoke, heat and mass transfer modeling to identify and solve fire 

11 protection problems for the commercial, government, and military sectors. Dr. Williamson’s 

12 experience includes research, development and analysis of advanced fire modeling. He has 

13 worked as a fire modeling software developer and has expertise in the application of model 

14 verification, validation, sensitivity and uncertainty analysis required for high level regulatory 

15 acceptance of modeling results. He is passionate about applying his scientific expertise to 

16 provide effective solutions to complex problems. 

17 PROFESSIONAL HIGHLIGHTS

18 Fire Protection Engineer, Hughes Associates, Baltimore, MD, 2008–present. Responsibilities 

19 include research, development and analysis of advanced fire simulations. Models used include 

20 Fire Dynamics Simulator (FDS), Consolidated Fire and Smoke Transport (CFAST), HEATING 

21 7.3, and Fire and Smoke SIMulator (FSSIM). Performs fundamental analysis of dynamic, 

22 thermo-physical problems associated with fire, including heat transfer, mass transfer, and fire 

23 dynamics. Developed various software tools including FSSIM and customized tools for various 

24 applications. Performed complex analyses including fire modeling code compliance evaluations, 

25 code equivalence evaluations, Fire Hazard Analyses (FHA), and support for Fire Probabilistic 

26 Risk assessment (PRA) in support of commercial, NRC and DOE facilities. Performed 

27 engineering inspections in support of fire PRA modeling for Main Control Room abandonment 

28 and NFPA 805 transition. Expertise in the application and development of model verification, 

29 validation, sensitivity and uncertainty analysis required for high level regulatory acceptance of 

30 modeling results. 

31 Internship, Exponent, Thermal Sciences Department, Bowie, MD, 2007–2008. Handled the 

32 experimental study of spill characteristics for cryogenic liquids on water and performed CFD 

33 simulations of large scale cryogenic liquid spill and dispersion. 

34 Graduate Research Assistant, University of Maryland, Department of Mechanical 

35 Engineering, College Park, MD, 2004–2007. Developed local extinction criteria for fire from 

36 counterflow flame studies to add more detailed combustion physics for under-ventilated fires in 

37 FDS. 

38 Faculty Research Assistant, University of Maryland, Department of Mechanical 

39 Engineering, College Park, MD, 2004. Assisted with the Maritime Hazard Assessment Project 

40 sponsored by the Department of Defense. Examined hazards of accidental release of cryogenic 

41 fuels from cargo ships. Incorporated a partially premixed combustion model in the NIST Fire 

42 Dynamics Simulator (FDS) to examine deflagrations. 

43 

 

3

 Not a working group member. 
WG MEMBERS, NON-WG CONTRIBUTORS, AND FACILITATOR RESUMES 

A-24 

1 Graduate Research Assistant, University of Maryland, Department of Mechanical 

2 Engineering, College Park, MD, 2002–2003. Characterized thermal behavior and ignition from 

3 cigarette lighter flames. Developed an inherently safe cigarette lighter to reduce the risk of 

4 unwanted ignition from juvenile misuse. 

5 

6 NOTABLE PUBLICATIONS AND PRESENTATIONS

7 

8 Williamson, J., "Measurements and Analysis of Extinction in Vitiated Flame Sheets," University 

9 of Maryland, College Park, MD, 2009. 

10 Williamson, J., "Characterizing Cigarette Lighter Flames to Reduce Unwanted Ignition," 

11 University of Maryland, College Park, MD, 2003. 

12 Williamson, J., Beyler, C., and Floyd, J., “Validation of Numerical Simulations of Compartments 

13 with Forced or Natural Ventilation using the Fire and Smoke Simulator (FSSIM), CFAST and 

14 FDS,” Interflam 2010: Proceedings of the Twelfth International Conference, University of 

15 Nottingham, United Kingdom, July 5–7, 2010, pp. 1043–1052. 

16 Williamson, J. and Marshall, A.W., “Characterizing the ignition hazard from cigarette lighter 

17 flames,” Fire Safety Journal, 40 (1), February 2005, DOI: 10.1016/j.firesaf.2004.08.004. 

18 
B-1 

1 

2 Appendix B

3 Overview of Working Group Activities 

4 This appendix provides a summary of the working group (WG) activities. The members of the 

5 WG convened four separate times in 2 to 21⁄2-day meetings from April 2014 through September 

6 2014 at the NRC’s RES building in Rockville, Maryland. Specifically, meetings were held on: 

7 

8 1. First meeting: April 1-3, 2014 

9 2. Second meeting: May 21-23, 2014 

10 3. Third meeting: July 22-24, 2014 

11 4. Fourth meeting: September 15-16, 2014 

12 

13 In addition, webinars and conference calls were scheduled throughout this period on an as14 needed basis. During the first two meetings, the WG evaluated two major avenues to address 

15 the modeling of electrical enclosure fire hazards: 

16 

17  Re-binning and redefining the peak HRR profiles for electrical enclosures (provided in 

18 Table G-1 of NUREG/CR-6850) based on the amount of combustible materials 

19 contained within electrical enclosures and the potential for an enclosure fire to grow to its 

20 maximum size (peak) when left undetected (i.e., fire severity), and then, 

21 

22  For each enclosure group or class, developing information in adjusting other effects of 

23 the peak HRR profile (or distribution) in the fire analysis. 

24 

25 During the first meeting, the WG members identified and discussed several topics to improve 

26 the current methodology for modeling electrical enclosure fire hazards in the fire PRA. Some of 

27 the items considered are presented in Table B-1. 

28 

Table B-1 

Identification of Topics for Consideration 

Topics or Concepts Identified Action Taken 

Classification (i.e., binning) of electrical enclosure 

types 

A new set of enclosure classifications was 

developed and described in Chapter 3 of 

this report. 

Characterizing the peak heat release rate for all 

enclosure types and other equipment (e.g., motors, 

pumps, dry transformers) with an electrical ignition 

source 

A new set of peak heat release rate 

probability distributions is described in 

Chapter 4 of this report. 

The characterization of peak heat release 

rates for ignition sources other than 

electrical enclosures is under review* and 

therefore, not included in this report. 

Effects of obstructed fire plume inside the 

enclosure on the vertical component of the zone of 

influence (i.e., fire plume temperatures) 

Chapters 5 and 6 of this report describe 

the recommended approach for 

incorporating the effects of obstructions in 

fire plume temperatures in a fire modeling 

analysis. 
OVERVIEW OF WORKING GROUP ACTIVITIES 

B-2 

Table B-1 

Identification of Topics for Consideration 

Topics or Concepts Identified Action Taken 

Assessment of heat release rate growth profile 

based on actual fire test results and fire 

experience, including the pre-growth, growth, and 

decay phases. 

This topic is under review* 

Evaluation of the effect of enclosure counting on 

the fire ignition frequency including treatment of 

“well-sealed” electrical enclosures in the counting 

process 

This topic is under review* 

Understanding the effects of ventilation-limited 

conditions associated with electrical enclosure fires

Chapter 4 of this report provides peak 

heat release rate distributions that are 

dependent on an electrical enclosure’s 

ventilation conditions (open or closed door 

configuration) 

This report does not cover the modeling 

heat release rates in ventilation limited 

conditions. This topic is under review* 

Guidelines on treatment of: 

a. Small electrical enclosures 

b. Large enclosures, walkthrough enclosures, 

and main control board 

c. Fire propagation to adjacent enclosures 

d. Fire resistance of SIS (manufacturer-wired 

safety cables), silicon rubber (SR), and 

Tefzel cable insulation types 

a. See Table 4-2 enclosure class 4c for 

treatment of small electrical 

enclosures 

b. See Table 4-2 enclosure class 4 for 

treatment of large electrical enclosures 

Treatment of main control board fire 

modeling and scenario development is 

under review* 

c. This topic is under review* 

d. This topic is under review* 

Examples of fire analysis of electrical enclosure 

fires 

Appendix G provides examples of the 

approach described in the report. 

1 * “Under review” does not imply that the NRC or EPRI intends to address this issue in future efforts. It is intended to 

2 recognize issues that were identified but not addressed in the current effort as documented in this report. 

3 

4 During the second meeting, the NRC staff presented the preliminary data of their recent fire 

5 testing of electrical enclosures at the CBD facility of the Naval Research Laboratory. In 

6 addition, the NRC staff presented a preliminary evaluation of experimental data on electrical 

7 enclosure fires from all four sources (i.e., SNL, VTT, IRSN, and CBD). 

8 

9 Also during the second meeting, the WG decided to evaluate the results of a set of Fire 

10 Dynamics Simulator (FDS) runs that simulated the fire plume behavior for fires within electrical 
OVERVIEW OF WORKING GROUP ACTIVITIES 

B-3

1 enclosures. This approach is referred to in this report as the obstructed plume. Preliminary 

2 simulations yielded some encouraging results and a test matrix was developed by the group for 

3 additional simulations and refinements. The simulation results were later presented and 

4 discussed during the third and fourth meetings in order to finalize the approach provided in 

5 Chapters 5 and 6 of this report. 

6 

7 Pictures of electrical enclosures typically installed in nuclear power plants and considered in fire 

8 PRA analyses were reviewed among the working group, during the second meeting. The 

9 pictures illustrated the electrical enclosure size and plant configurations, as well as the internal 

10 components that could act as the fire ignition source. Considering the overall size/configuration, 

11 the ignition source strength, and the amount of internal combustibles, the WG subsequently 

12 reached a consensus in classifying electrical enclosures into two major categories: one based 

13 on the electrical function and the other based on the size of an enclosure. After binning the 

14 switchgear, load centers, motor control centers (MCCs), battery chargers, and power inverters 

15 into three groups within the “electrical function” major group, the WG decided to group all other 

16 remaining enclosure types (mostly control and instrument panels) into three specific subgroups 

17 based on their volumetric size (e.g., small, medium, and large). Thus, the WG classified all 

18 enclosures into six specific classification groups. 

19 

20 In preparation for the third meeting, a webinar was held on June 26, 2014, for the WG to 

21 discuss how to correlate peak heat release rate values with a specific amount of combustible 

22 materials using the videos from various fire test programs. 

23 

24 The third working group meeting on July 22-24, 2014, fast-tracked the technical work on the 

25 heat release rate distributions and the obstructed plume approach. The WG’s focus during the 

26 July meeting was concentrated on the HRR distributions for the enclosure classification groups 

27 developed in the prior meeting. For each enclosure type, a consensus approach was used to 

assign the 75th and 98th 28 values based on the individual research, data analysis, and engineering 

29 judgment. 

30 

31 During the fourth meeting, the WG finalized the definitions of the volumetric classification of 

32 other enclosures, including the subcategories for large and medium categories. The WG also 

33 reached a consensus on the final HRR distribution estimates. In addition to finalizing the peak 

34 HRR values for all electrical enclosure classes, the WG reviewed the findings of the obstructed 

35 plume study. Based on the comments by several WG members, the resulting approach was 

36 finalized with additional information for completeness and clarity of all assumptions and 

37 limitations addressed in the FDS simulations. 

38 

39 

C-1 

1 Appendix C

2 Photographs Supporting Classification of Electrical 

3 Enclosures 

4 

5 This appendix provides a collection of photographs for the six classification groups of electrical 

6 enclosures defined in Chapter 3 of this report. The intent of the information is to support the 

7 classification of electrical enclosures. The photographs represent electrical enclosures typically 

8 found in nuclear power facilities. Some of them are taken from non-nuclear sources. 

9 

10 It should be noted that all figures included in this appendix are intended to assist the analyst for 

selecting and classifying Bin 151 11 cabinets in a typical NPP. The final judgment on assigning a 

12 classification group should be based on the information given in Section 3 and adequately 

13 documented (with photo illustrating actual internal and fuel configurations). 

14 C.1 Group 1: Switchgear and Load Centers 

15 C.1.1 Switchgear 

16 Switchgear is a general term covering switching and interrupting devices and their combination 

17 with associated control, instrumentation, metering, protective, and regulating devices. Common 

18 switchgear voltage classifications found in an NPP include medium voltage (4.16 kV, 6.9 kV, 7.2 

19 kV, 12.7 kV, 13.9 kV, etc.), and low voltage (480 V, 600 V). Switchgears are used to direct flow 

20 of power to various feeders and to isolate apparatus and circuit from the power system. Figures 

21 C-1 through C-4 provide examples of external and internal photographs of medium voltage 

22 switchgear equipment. 

23 

24 

25 26 

27 Figure C-1 

28 Front View of Medium Voltage Switchgear Banks 

29 

 

1

 In addition to Bin 15 enclosures, the enclosures here include main control board (Bin 4) and battery 

charger (Bin 10). 
PHOTOGRAPHS SUPPORTING CLASSIFICATION OF ELECTRICAL ENCLOSURES 

C-2 

1 

2 

3 

4 

5 

6 

7 

8 

9 

10 

11 

12 Figure C-2 

13 Front View of 6.9 kV Switchgear Relay and Control Logic Enclosures 

14 

15 
PHOTOGRAPHS SUPPORTING CLASSIFICATION OF ELECTRICAL ENCLOSURES 

C-3 

1 2 

3 

4 

5 Figure C-3 

6 Internal Views of Medium Voltage Switchgear 

7 

8 

9 

10 

11 
PHOTOGRAPHS SUPPORTING CLASSIFICATION OF ELECTRICAL ENCLOSURES 

C-4 

1 

2 3 

4 

5 Figure C-4 

6 Internal Views of Medium Voltage Switchgear, Back Showing Bus Cables (Left), Front Showing 

7 Control and Relay Enclosure (Right) 

8 

9 

10 
PHOTOGRAPHS SUPPORTING CLASSIFICATION OF ELECTRICAL ENCLOSURES 

C-5 

1 C.1.2 Low Voltage Switchgear and Load Centers 

2 Load centers are low voltage switchgears that are typically used to distribute power to motor 

3 control centers (MCCs). Load centers commonly have a medium voltage to low voltage 

4 transformer and a lineup of low voltage switchgear. Figures C-5 through C-10 provide example 

5 photographs of low voltage switchgear/load centers. 

6 

7 

8 

9 Figure C-5 

10 Front View of Load Center (Disconnect Switch) 

11 

12 

13 14 

15 Figure C-6 

16 Internal Views of a Load Center (a) Low Voltage Breaker, (b) Empty Breaker Cubicle, and (c) 

17 Load Center Control Cubicle 

18 

(a) (b) (c) 
PHOTOGRAPHS SUPPORTING CLASSIFICATION OF ELECTRICAL ENCLOSURES 

C-6 

1 

2 

3 Figure C-7 

4 Load Center (Left) with Oil-Cooled Transformer (Right) 

5 

6 

7 

8 Figure C-8 

9 Front View of Load Center (Right) and Transformer (Left) 

10 

11 
PHOTOGRAPHS SUPPORTING CLASSIFICATION OF ELECTRICAL ENCLOSURES 

C-7 

1 

2 

3 Figure C-9 

4 Front View of Load Center (Low Voltage Switchgear) 

5 

6 

7 8 

9 Figure C-10 

10 Low Voltage Load Center Breaker 

11 
PHOTOGRAPHS SUPPORTING CLASSIFICATION OF ELECTRICAL ENCLOSURES 

C-8 

1 C.2 Group 2: Motor Control Centers and Battery Chargers 

2 C.2.1 Motor Control Centers 

3 Low voltage motor control centers (MCCs) contain an externally operable circuit disconnecting 

4 means, circuit overprotection, and a magnetic motor controller with auxiliary devices combined 

5 in plug-in units in vertical assemblies. Control power transformers may be included to provide a 

6 120 VAC power source for the control portion of the equipment, rather than use in the 480 V or 

7 600 V supply voltage. Vertical and horizontal compartmentalized wire-ways are commonly 

8 provided to allow for ease of installation and configuration changes. Figures C-11 and C-12 

9 provide external and internal photographs of MCCs. 

10 

11 

12 

13 

14 

15 Figure C-11 

16 Front View of MCC with Three Vertical Sections 
PHOTOGRAPHS SUPPORTING CLASSIFICATION OF ELECTRICAL ENCLOSURES 

C-9 

1 

2 

3 Figure C-12 

4 Internal Views of MCC Cubicle 

5 

6 C.2.2 Battery Chargers 

7 Battery chargers convert alternating current (AC) into a highly regulated direct current (DC) 

8 output that is used to charge the station backup batteries and to supply all continuous loads that 

9 may be connected to the bus. Battery chargers can be specified to accept any available input 

10 voltage, either single- or three-phase. The most common nominal AC input voltages are 120 V, 

11 208 V, and 240 V single-phase voltage, and 120/208 V or 277/480 V for three-phase voltage. 

12 Nominal DC output voltages are 12 V, 24 V, 48 V, 125 V, and 250 V. Figures C-13 and C-14 

13 present the external and internal photographs of battery chargers, respectively. 

14 

15 

16 

17 Figure C-13 

18 Front View of a Battery Charger 

19 
PHOTOGRAPHS SUPPORTING CLASSIFICATION OF ELECTRICAL ENCLOSURES 

C-10 

1 

2 3 

4 Figure C-14 

5 Internal Views of Battery Chargers 

6 C.3 Group 3: Power Inverters 

7 An inverter changes direct current (DC) power to alternating current (AC) power. Figure C-15 

8 presents external photographs of inverters, while Figure C-16 presents internal photographs of 

9 inverters. 

10 

11 12 Figure C-15 

13 Power Inverters – Front and Back 

14 
PHOTOGRAPHS SUPPORTING CLASSIFICATION OF ELECTRICAL ENCLOSURES 

C-11 

1 

2 3 

4 Figure C-16 

5 Power Inverters – Internal Views 

6 
PHOTOGRAPHS SUPPORTING CLASSIFICATION OF ELECTRICAL ENCLOSURES 

C-12 

1 C.4 Group 4a: Large Enclosures 

2 Large enclosures are electrical enclosures of physical volumetric dimensions greater than 50 

3 cubic feet. The large enclosure category does not include power distribution enclosures such 

4 as switchgear, load centers, and motor control centers. Figures C-17 through C-20 show large 

5 enclosures in the closed and open configurations. 

6 

7 

8 

9 Figure C-17 

10 Auxiliary Shutdown Panels – Large Enclosure (Closed) 

11 

12 

13 

14 Figure C-18 

15 Large Closed Electrical Enclosure 

16 
PHOTOGRAPHS SUPPORTING CLASSIFICATION OF ELECTRICAL ENCLOSURES 

C-13 

1 

2 

3 

4 

5 Figure C-19 

6 Large Closed Electrical Enclosure (Main Control Board – MCB) 
PHOTOGRAPHS SUPPORTING CLASSIFICATION OF ELECTRICAL ENCLOSURES 

C-14 

1 

2 

3 Figure C-20 

4 Large Open Electrical Enclosure (Walkthrough Enclosure) 

5 

6 C.5 Group 4b: Medium Enclosures 

7 Medium enclosures are electrical enclosures of physical volumetric dimensions greater than 12 

8 cubic feet and less than or equal to 50 cubic feet. Figure C-21 presents photographs of 

9 electrical enclosures representative of the medium enclosure category. 

10 

11 12 

13 Figure C-21 

14 Medium Enclosure (Approximately 2 ft. x 2 ft. x 7 ft.) 

15 
PHOTOGRAPHS SUPPORTING CLASSIFICATION OF ELECTRICAL ENCLOSURES 

C-15 

1 C.6 Group 4c: Small Enclosures 

2 Small enclosures are small enclosures or panels less than 12 cubic feet in physical dimensions. 

3 Small switching enclosures include wall mounted distribution panels (Figures C-22 and C-24), 

4 and disconnect switches (Figure C-23). 

5 

6 7 

8 Figure C-22 

9 Wall Mounted Small Enclosures 

10 

11 

12 13 

14 Figure C-23 

15 Wall Mounted Low Voltage AC Fused Disconnect Switches 

16 

17 

18 
PHOTOGRAPHS SUPPORTING CLASSIFICATION OF ELECTRICAL ENCLOSURES 

C-16 

1 2 

3 Figure C-24 

4 125 VDC Distribution Panel (Left) and 120 VAC Distribution Panel (Right) 

5 

6 C.7 Large (Group 4a) and Medium (Group 4b) Enclosure 

7 Internals 

8 C.7.1 “Default” Loading Configurations [Sub-Category 4a(a) and 

9 4b(a)] 

10 Figures C-25 through C-27 provide examples of internal electrical enclosure combustible mass 

11 and loading configurations for which the “Default” HRR values in Table 4-2 are recommended to 

12 be used. 

13 

14 

15 

16 

17 

18 

19 

20 

21 

22 
PHOTOGRAPHS SUPPORTING CLASSIFICATION OF ELECTRICAL ENCLOSURES 

C-17 

1 

2 

3 4 

5 

6 

7 Figure C-25 

8 Internal Enclosure Fuel Loading for Default Sub-Category (1 of 3) 

9 Note in particular the enclosure to the upper left, which has disorderly internal enclosure wiring and 

10 loose legacy or extra field wires at the bottom.

11 

12 

13 
PHOTOGRAPHS SUPPORTING CLASSIFICATION OF ELECTRICAL ENCLOSURES 

C-18 

1 2 

3 4 

5 Figure C-26 

6 Internal Enclosure Fuel Loading for Default Sub-Category (2 of 3) 

7 The bottom examples are somewhat extreme in terms of cable loading and loose bundling. Note 

8 in particular the enclosure to the lower left, which has a combination of orderly internal enclosure 

9 wiring (white wires on the right side of the enclosure) and loose disorderly field wires (center).

10 

11 
PHOTOGRAPHS SUPPORTING CLASSIFICATION OF ELECTRICAL ENCLOSURES 

C-19 

1 2 

3 Figure C-27 

4 Internal Enclosure Fuel Loading for Default Sub-Category (3 of 3) 

5 Note that the enclosures on the left and right have many small cables that are not tightly bundled. 

6 The enclosure in the center has a significant load of printed circuit cards which are also combustible. 

7 

8 C.7.2 “Low Fuel Loading” Configurations [Sub-Category 4a(b) and 

9 4b(b)] 

10 “Low Fuel Loading” HRR estimates can be used for electrical enclosures whose internal panel 

11 wiring is tightly bundled throughout the enclosure. The tight bundling configuration is believed 

12 to reduce the surface area of polymeric material being heated from thermal fire conditions and 

13 limits to some extent the availability of oxygen to interact with the surface of the combustible. 

14 Thus, the tight bundling is believed to reduce the spread rate and heat release rate as shown 

15 from experimental testing, and the recommended HRR distributions in Table 4-2 could be used. 

16 Figures C-28 and C-29 present internal photographs of electrical enclosures containing panel 

17 wiring tightly bundled. 

18 
PHOTOGRAPHS SUPPORTING CLASSIFICATION OF ELECTRICAL ENCLOSURES 

C-20 

1 2 

3 4 

5 Figure C-28 

6 Examples of “Low Fuel Loading” Sub-Category (1 of 2) 

7 Note that cables are neatly routed and tightly bundled and that there is a relatively 

8 low fuel loading given the overall enclosure volume. 

9 
PHOTOGRAPHS SUPPORTING CLASSIFICATION OF ELECTRICAL ENCLOSURES 

C-21 

1 

2 3 

4 Figure C-29 

5 Examples of “Low Fuel Loading” Sub-Category (2 of 2) 

6 Note that larger size cables are neatly routed and tightly bundled and that 

7 there is a relatively low fuel loading given the overall enclosure volume. 

8 

9 C.7.3 “Very Low Fuel Loading” Configurations [Sub-Category 4a(c) 

10 and 4b(c)] 

11 “Very Low Fuel Loading” HRR estimates can be used for electrical enclosures that have limited 

12 internal panel wiring throughout the enclosure. To classify an electrical enclosure “Very Low 

13 Fuel Loading” the internal combustible loading of an electrical enclosure must be minimal (less 

14 than 5% combustible volume) and the HRR distributions in Table 4-2 could be used. Figure 

15 C-30 presents internal photographs of electrical enclosures with limited panel wiring 

16 representative of the “Very Low Fuel Loading” configuration. 

17 

18 
PHOTOGRAPHS SUPPORTING CLASSIFICATION OF ELECTRICAL ENCLOSURES 

C-22 

1 

2 

3 

4 Figure C-30 

5 Examples of “Very Low Fuel Loading” Sub-Category 

6 

7 

8 
D-1

1 Appendix D

2 Electrical Cabinet Heat Release Rate Data Analysis 

3 

4 This appendix provides technical details for determining the alpha and beta parameters for the 

5 gamma distributions representing the peak heat release rate (HRR) for electrical enclosures. A 

6 total of 25 different electrical enclosure classifications have been assigned gamma probability 

7 distributions. The classifications are based on type of cabinets (i.e., cabinet function), size, 

8 doors open or closed, thermoset (TS) or thermoplastic (TP) cables, and cable loading. The list 

9 of data sources used in the current analysis is provided in Appendix D.1. The data classification 

10 for each cabinet fire test is presented in a matrix format in Appendix D.2. The alpha and beta 

11 parameters characterizing each gamma distribution are provided in Appendix D.3. Appendix 

12 D.3 also describes the methodology for calculating the values within the Microsoft Excel 

13 Workbook. Finally, in Appendix D.4, a figure is provided for each cabinet classification, 

14 comparing the empirical distribution and the gamma distributions recommended by the working 

15 group. 

16 D.1 Data Sources 

17 The following test reports contain the results of fire experiments involving electrical cabinets that 

18 are commonly used in nuclear power plants (NPPs). Following each reference, the tests that 

19 are included and excluded in the current analysis are identified. 

20  Chavez, J. (1987), An Experimental Investigation of Internally Ignited Fires in Nuclear 

21 Power Plant Control Cabinets: Part I: Cabinet Effects Tests, NUREG/CR-4527 

22 Volume 1, U.S. Nuclear Regulatory Commission, Washington, DC. 

23 o All tests SNL-ST1 through SNL-ST11 are included in the analysis. 

24 o Tests SNL-PCT1, SNL-PCT3, SNL-PCT5, and PCT6 are included in the 

25 analysis. 

26  SNL-PCT2 is excluded because the test involved a large ignition source 

27 that is not representative of NPPs. 

28  SNL-PCT4A and SNL-PCT4C are excluded because the tests did not 

29 involve cables. 

30  Chavez, J., Nowlen, S. (1988), An Experimental Investigation of Internally Ignited Fires 

31 in Nuclear Power Plant Control Cabinets: Part II: Room Effects Tests, NUREG/CR-4527 

32 Volume 2, U.S. Nuclear Regulatory Commission, Washington, DC. 

33 o Tests 24 and 25 are included in the analysis 

34  Test 21 and Test 22 are excluded because the tests did not involve 

35 cables. 

36  Test 23 is excluded because the test involved a transient ignition source 

37 that is not representative of NPPs. 

38  Mangs, J., Keski-Rahkonen, O. (1994), Full Scale Fire Experiments on Electronic 

39 Cabinets, VTT Publications 186, VTT Technical Research Centre of Finland. 

40 o All VTT186 tests are included. 
ELECTRICAL CABINET HEAT RELEASE RATE DATA ANALYSIS 

D-2 

1  Mangs, J., Keski-Rahkonen, O. (1996), Full Scale Fire Experiments on Electronic 

2 Cabinets II, VTT Publications 269, VTT Technical Research Centre of Finland. 

3 o All VTT269 tests are included. 

4  Mangs, J. (2004), On the Fire Dynamics of Vehicles and Electrical Equipment, VTT 

5 Publications 521, VTT Technical Research Centre of Finland. 

6 o All VTT521 tests are included. 

7  Plumecocq, W., M. Coutin, S. Melis, L. Rigollet (2011), Characterization of closed-doors 

8 electrical cabinet fires in compartments, Fire Safety Journal 46, pp. 243-253. 

9 o CAA and CAB test series are excluded because the contents of the cabinets 

10 were not typical of electrical cabinets in NPPs; i.e., polymethyl methacrylate 

11 (PMMA). 

12 o CAO tests are excluded because the contents of the cabinets are not well 

13 characterized. 

14  McGrattan, K., S. Bareham (2014), Heat Release Rates of Electrical Enclosure Fires 

15 (HELEN-FIRE), NUREG/CR-7197, National Institute of Standards and Technology, 

16 Gaithersburg, Maryland. 

17 o All tests CBD-1 through CBD-112 are included. 

18 D.2 Data Classification 

19 The experimental data referenced in Appendix D.1 are classified in Table D-1 below. The 

20 categories are based on: 

21 Doors: Open (O) or Closed (C). In addition, closed and open door data for Power SWGR, 

22 Power MCC, and Control Small are grouped together. 

23 Thermoset (TS) or Thermoplastic (TP). For the purposes of this data classification, 

24 experiments using qualified cable are designated as thermoset. Experiments with unqualified 

25 cables are designated as thermoplastic. 

Enclosure Size: Small (S), <0.3 m3

 (12 ft3); Medium (M), 0.3 m3 to 1.7 m3 (12 ft3 to 60 ft3 26 ); 

Large (L), >1.4 m3

 (50 ft3 27 ). Comments in the last column of Table D-1 provide exceptions to 

28 these categories, for example medium cabinets with heavy cable loading are put in the Large 

classification. Notice that cabinets between 1.4 m3

 and 1.7 m3 (50 ft3 and 60 ft3 29 ) are classified 

30 as both Medium and Large. 

31 Cable Loading: Default (D) or Low (L). This category describes how the cables are 

32 configured, based on visual inspection of photographs. Default refers to cables that are hanging 

33 loose and not neatly bundled. Low refers to cables that are neatly bundled. Default is also 

34 used when the cable loading is unknown. 

35 Fuel Mass: Kilograms of fuel within the cabinet 

36 Types of Cabinets: 

37 Power switchgear and load center (Power SWGR & LC): contains one small bundle 

38 within the breaker box; most cables are located at the top; contains three unspliced 

39 cables in the back; contains spliced cables for the control/monitoring equipment 
ELECTRICAL CABINET HEAT RELEASE RATE DATA ANALYSIS 

D-3 

1 Power motor control center and charger (Power MCC): contains one small bundle 

2 within the breaker box; most cables are located at the top; contains only three unspliced 

3 cables in the back 

Control Large: Large Control cabinets (volume >1.4 m3

 (50 ft3 4 )), see comment column 

5 for exceptions 

6 Control Medium and Inverter (Control Medium): Medium Control cabinets and 

inverters (volume 0.3 m3

 to 1.7 m3 (12 ft3 to 60 ft3 7 )), see comment column for exceptions 

Control Small: Small Control cabinets (cabinet volume <0.3 m3

 (12 ft3 8 ) or fuel mass <1 

9 kg) 

10 Low or VLow: The Control cabinets with “Low” or “VLow” in the title refer to the Cable 

11 Loading of the cabinet. The experimental data is divided into two classifications—default 

12 and low—based on visual inspection. If the Cable Loading is Low, the experimental data 

13 is included in the columns marked Low and VLow. The distinction between Low and 

14 VLow is used by the expert panel. The panel developed gamma distributions for three 

15 classifications—default, low, and very low—which are used for comparison to the 

16 experimental data, as shown in Appendix D.3 and Appendix D.4. 

17 Classification: Heat release rate (kW) or FALSE (F). For each test that is included, the peak 

18 HRR is provided in kilowatts. If the experiment is not included, FALSE (F) is indicated. 

19 
Table D-1 

Matrix of Experiments and Cabinet Characteristics

Test ID Characteristics of the Experiments Types of Cabinets (Heat Release Rate of Experiment, kW) 

Doors 

Thermo-set or Thermo-plastic 

Enclosure Size 

Cable Loading 

Fuel Mass (kg) 

Power SWGR & LC TS 

Power SWGR & LC TP 

Power MCC TS 

Power MCC TP 

Control Large Close TS 

Control Large Close TS (Low) 

Control Large Close TS (VLow) 

Control Large Close TP 

Control Large Close TP (Low) 

Control Large Close TP (VLow) 

Control Large Open TS 

Control Large Open TS (Low) 

Control Large Open TS (VLow) 

Control Large Open TP 

Control Large Open TP (Low) 

Control Large Open TP (VLow) 

Control Medium Close TS 

Control Medium Close TS (Low) 

Control Medium Close TP 

Control Medium Close TP (Low) 

Control Medium Open TS 

Control Medium Open TS (Low) 

Control Medium Open TP 

Control Medium Open TP (Low) 

Control Small 

Comment 

SNL-ST1 O TS M, L D N/A 24 F 24 F F F F F F F 24 F F F F F F F F F 24 F F F FSNL-ST2 O TS M, L D N/A 27 F 27 F F F F F F F 27 F F F F F F F F F 27 F F F FSNL-ST3 O TS M, L D N/A 77 F 77 F F F F F F F 77 F F F F F F F F F 77 F F F FSNL-ST4 O TS M, L D N/A 82 F 82 F F F F F F F 82 F F F F F F F F F 82 F F F FSNL-ST5 O TP M, L D N/A F F F F F F F F F F F F F 132 F F F F F F F F 132 F FSNL-ST6 O TS L D N/A F F F F F F F F F F 82 F F F F F F F F F F F F F FSNL-ST7 C TS L D N/A F F F F 95 F F F F F F F F F F F F F F F F F F F FSNL-ST8 C TS L D N/A F F F F 93 F F F F F F F F F F F F F F F F F F F FSNL-ST9 O TS L D N/A F F F F F F F F F F 74 F F F F F F F F F F F F F FSNL-ST10 C TP L N N/A F F F F F F F 280 F F F F F F F F F F F F F F F F FSNL-ST11 O TP L D N/A F F F F F F F F F F F F F 506 F F F F F F F F F F FSNL-PCT1 C TP L D N/A F F F F F F F 185 F F F F F F F F F F F F F F F F FSNL-PCT3 O TS L D N/A F F F F F F F F F F 56 F F F F F F F F F F F F F FSNL-PCT5 O TP L D N/A F F F F F F F F F F F F F 791 F F F F F F F F F F FSNL-PCT6 O TS L D N/A F F F F F F F F F F 215 F F F F F F F F F F F F F F

D-4 ____________________________________________________________________________ 

ELECTRICAL CABINET HEAT RELEASE RATE DATA ANALYSIS
Table D-1 

Matrix of Experiments and Cabinet Characteristics

Test ID Characteristics of the Experiments Types of Cabinets (Heat Release Rate of Experiment, kW) 

Doors 

Thermo-set or Thermo-plastic 

Enclosure Size 

Cable Loading 

Fuel Mass (kg) 

Power SWGR & LC TS 

Power SWGR & LC TP 

Power MCC TS 

Power MCC TP 

Control Large Close TS 

Control Large Close TS (Low) 

Control Large Close TS (VLow) 

Control Large Close TP 

Control Large Close TP (Low) 

Control Large Close TP (VLow) 

Control Large Open TS 

Control Large Open TS (Low) 

Control Large Open TS (VLow) 

Control Large Open TP 

Control Large Open TP (Low) 

Control Large Open TP (VLow) 

Control Medium Close TS 

Control Medium Close TS (Low) 

Control Medium Close TP 

Control Medium Close TP (Low) 

Control Medium Open TS 

Control Medium Open TS (Low) 

Control Medium Open TP 

Control Medium Open TP (Low) 

Control Small 

Comment 

SNL-Test24 O TP L D N/A F F F F F F F F F F F F F 1300 F F F F F F F F F F FSNL-Test25 O TP L D N/A F F F F F F F F F F F F F 840 F F F F F F F F F F FVTT186-Exp1 C TP M D N/A F F F F F F F 400 F F F F F F F F F F F F F F F F F 1 VTT186-Exp2 C TP M D N/A F F F F F F F 50 F F F F F F F F F F F F F F F F F 1 VTT186-Exp3-1 C TP M D N/A F F F F F F F 0 F F F F F F F F F F F F F F F F F 1 VTT186-Exp3-2 C TP M D N/A F F F F F F F 200 F F F F F F F F F F F F F F F F F 1 VTT269-Exp1 C TP M D N/A F F F F F F F 180 F F F F F F F F F F F F F F F F F 1 VTT269-Exp2A C TP M D N/A F F F F F F F 0 F F F F F F F F F F F F F F F F F 1 VTT269-Exp2B C TP M D N/A F F F F F F F 0 F F F F F F F F F F F F F F F F F 1 VTT269-Exp2C C TP M D N/A F F F F F F F 120 F F F F F F F F F F F F F F F F F 1 VTT269-Exp3 C TP M D N/A F F F F F F F 100 F F F F F F F F F F F F F F F F F 1 VTT521-Exp1 C TP M D N/A F F F F F F F 175 F F F F F F F F F F F F F F F F F 1 VTT521-Exp2A C TP M D N/A F F F F F F F 0 F F F F F F F F F F F F F F F F F 1 VTT521-Exp2B C TP M D N/A F F F F F F F 0 F F F F F F F F F F F F F F F F F 1 VTT521-Exp2C C TP M D N/A F F F F F F F 125 F F F F F F F F F F F F F F F F F 1 VTT521-Exp3 C TP M D N/A F F F F F F F 100 F F F F F F F F F F F F F F F F F 1 

D-5 ____________________________________________________________________________ 

ELECTRICAL CABINET HEAT RELEASE RATE DATA ANALYSIS
Table D-1 

Matrix of Experiments and Cabinet Characteristics

Test ID Characteristics of the Experiments Types of Cabinets (Heat Release Rate of Experiment, kW) 

Doors 

Thermo-set or Thermo-plastic 

Enclosure Size 

Cable Loading 

Fuel Mass (kg) 

Power SWGR & LC TS 

Power SWGR & LC TP 

Power MCC TS 

Power MCC TP 

Control Large Close TS 

Control Large Close TS (Low) 

Control Large Close TS (VLow) 

Control Large Close TP 

Control Large Close TP (Low) 

Control Large Close TP (VLow) 

Control Large Open TS 

Control Large Open TS (Low) 

Control Large Open TS (VLow) 

Control Large Open TP 

Control Large Open TP (Low) 

Control Large Open TP (VLow) 

Control Medium Close TS 

Control Medium Close TS (Low) 

Control Medium Close TP 

Control Medium Close TP (Low) 

Control Medium Open TS 

Control Medium Open TS (Low) 

Control Medium Open TP 

Control Medium Open TP (Low) 

Control Small 

Comment 

VTT521-Exp4 C TP M D N/A F F F F F F F 400 F F F F F F F F F F F F F F F F F 1 VTT521-Exp5 C TP M D N/A F F F F F F F 50 F F F F F F F F F F F F F F F F F 1 VTT521-Exp6A C TP M D N/A F F F F F F F 0 F F F F F F F F F F F F F F F F F 1 VTT521-Exp6B C TP M D N/A F F F F F F F 200 F F F F F F F F F F F F F F F F F 1 VTT521-Exp7 C TP S D N/A F F F F F F F F F F F F F F F F F F F F F F F F 35VTT521-Exp8 C TP S D N/A F F F F F F F F F F F F F F F F F F F F F F F F 20VTT521-Exp9 C TP S D N/A F F F F F F F F F F F F F F F F F F F F F F F F 40VTT521-Exp10 C TP S D N/A F F F F F F F F F F F F F F F F F F F F F F F F 20CBD-1 O TS M D 0.1 F F F F F F F F F F F F F F F F F F F F F F F F 2 2 CBD-2 O TS M L 0.1 F F F F F F F F F F F F F F F F F F F F F F F F 2 2 CBD-3 O TS M L 0.1 F F F F F F F F F F F F F F F F F F F F F F F F 2 2 CBD-4 O TS M L 0.1 F F F F F F F F F F F F F F F F F F F F F F F F 2 2 CBD-5 O TS M L 0.1 F F F F F F F F F F F F F F F F F F F F F F F F 1 2 CBD-6 O TS M, L L 0.1 F F F F F F F F F F F F F F F F F F F F F F F F 2 2 CBD-7 O TS M, L L 0.1 F F F F F F F F F F F F F F F F F F F F F F F F 9 2 CBD-8 O TS L D 0.1 F F F F F F F F F F F F F F F F F F F F F F F F 0 2 

D-6 ____________________________________________________________________________ 

ELECTRICAL CABINET HEAT RELEASE RATE DATA ANALYSIS
Table D-1 

Matrix of Experiments and Cabinet Characteristics

Test ID Characteristics of the Experiments Types of Cabinets (Heat Release Rate of Experiment, kW) 

Doors 

Thermo-set or Thermo-plastic 

Enclosure Size 

Cable Loading 

Fuel Mass (kg) 

Power SWGR & LC TS 

Power SWGR & LC TP 

Power MCC TS 

Power MCC TP 

Control Large Close TS 

Control Large Close TS (Low) 

Control Large Close TS (VLow) 

Control Large Close TP 

Control Large Close TP (Low) 

Control Large Close TP (VLow) 

Control Large Open TS 

Control Large Open TS (Low) 

Control Large Open TS (VLow) 

Control Large Open TP 

Control Large Open TP (Low) 

Control Large Open TP (VLow) 

Control Medium Close TS 

Control Medium Close TS (Low) 

Control Medium Close TP 

Control Medium Close TP (Low) 

Control Medium Open TS 

Control Medium Open TS (Low) 

Control Medium Open TP 

Control Medium Open TP (Low) 

Control Small 

Comment 

CBD-9 O TS L D 0.1 F F F F F F F F F F F F F F F F F F F F F F F F 1 2 CBD-10 O TS L D 0.1 F F F F F F F F F F F F F F F F F F F F F F F F 1 2 CBD-11 O TS M D 11 F F F F F F F F F F F F F F F F F F F F 1 F F F FCBD-12 C TS M D 11 F F F F F F F F F F F F F F F F 52 F F F F F F F FCBD-13 C TS M D 0.1 F F F F F F F F F F F F F F F F F F F F F F F F 2 2 CBD-14 C TS M D 0.1 F F F F F F F F F F F F F F F F F F F F F F F F 4 2 CBD-15 O TS M, L L 3.4 3 F 3 F F F F F F F F 3 3 F F F F F F F F 3 F F FCBD-16 O TS M, L L 1.9 F F F F F F F F F F F 2 2 F F F F F F F F 2 F F FCBD-17 O TS M, L L 2.7 0 F 0 F F F F F F F F 0 0 F F F F F F F F 0 F F FCBD-18 O TP M, L L 1.8 F F F F F F F F F F F F F F 3 3 F F F F F F F 3 FCBD-19 C TS M, L L 3.4 F F F F F 3 3 F F F F F F F F F F 3 F F F F F F FCBD-20 C TS M, L L 1.9 F F F F F 5 5 F F F F F F F F F F 5 F F F F F F FCBD-21 C TS M, L L 1.9 4 F 4 F F 4 4 F F F F F F F F F F 4 F F F F F F FCBD-22 C TS M, L L 1.9 F F F F F 4 4 F F F F F F F F F F 4 F F F F F F FCBD-23 O TP M, L L 1.6 F F F F F F F F F F F F F F 18 18 F F F F F F F 18 FCBD-24 C TS M, L L 0.7 F F F F F F F F F F F F F F F F F F F F F F F F 4 2 

D-7 ____________________________________________________________________________ 

ELECTRICAL CABINET HEAT RELEASE RATE DATA ANALYSIS
Table D-1 

Matrix of Experiments and Cabinet Characteristics

Test ID Characteristics of the Experiments Types of Cabinets (Heat Release Rate of Experiment, kW) 

Doors 

Thermo-set or Thermo-plastic 

Enclosure Size 

Cable Loading 

Fuel Mass (kg) 

Power SWGR & LC TS 

Power SWGR & LC TP 

Power MCC TS 

Power MCC TP 

Control Large Close TS 

Control Large Close TS (Low) 

Control Large Close TS (VLow) 

Control Large Close TP 

Control Large Close TP (Low) 

Control Large Close TP (VLow) 

Control Large Open TS 

Control Large Open TS (Low) 

Control Large Open TS (VLow) 

Control Large Open TP 

Control Large Open TP (Low) 

Control Large Open TP (VLow) 

Control Medium Close TS 

Control Medium Close TS (Low) 

Control Medium Close TP 

Control Medium Close TP (Low) 

Control Medium Open TS 

Control Medium Open TS (Low) 

Control Medium Open TP 

Control Medium Open TP (Low) 

Control Small 

Comment 

CBD-25 C TS M D 3.1 F F F F F F F F F F F F F F F F 4 F F F F F F F FCBD-26 C TS M D 3.1 F F F F F F F F F F F F F F F F 1 F F F F F F F FCBD-27 C TS M D 3.1 F F F F F F F F F F F F F F F F 1 F F F F F F F FCBD-28 C TS M D 3.1 F F F F F F F F F F F F F F F F 1 F F F F F F F FCBD-28B O TS M D 3.1 F F F F F F F F F F F F F F F F F F F F 10 F F F FCBD-29 C TS M D 3.1 F F F F F F F F F F F F F F F F 82 F F F F F F F FCBD-30 C TS M D 3.1 F F F F F F F F F F F F F F F F 72 F F F F F F F FCBD-31 C TS M, L D 0.7 F F F F F F F F F F F F F F F F F F F F F F F F 28 2 CBD-32 C TS M, L D 0.7 F F F F F F F F F F F F F F F F F F F F F F F F 6 2 CBD-33 C TS M, L D 1.5 F F F F 50 F F F F F F F F F F F 50 F F F F F F F FCBD-34 C TS M, L D 1.5 F F F F 35 F F F F F F F F F F F 35 F F F F F F F FCBD-35 O TS M D 12 F F F F F F F F F F F F F F F F F F F F 146 F F F FCBD-36 C TS M D 2.8 F F F F F F F F F F F F F F F F 4 F F F F F F F FCBD-37 C TS M D 5.5 F F F F F F F F F F F F F F F F 35 F F F F F F F FCBD-38 C TS M D 5.5 F F F F F F F F F F F F F F F F 169 F F F F F F F FCBD-39 C TS M D 5.8 F F F F F F F F F F F F F F F F 60 F F F F F F F F

D-8 ____________________________________________________________________________ 

ELECTRICAL CABINET HEAT RELEASE RATE DATA ANALYSIS
Table D-1 

Matrix of Experiments and Cabinet Characteristics

Test ID Characteristics of the Experiments Types of Cabinets (Heat Release Rate of Experiment, kW) 

Doors 

Thermo-set or Thermo-plastic 

Enclosure Size 

Cable Loading 

Fuel Mass (kg) 

Power SWGR & LC TS 

Power SWGR & LC TP 

Power MCC TS 

Power MCC TP 

Control Large Close TS 

Control Large Close TS (Low) 

Control Large Close TS (VLow) 

Control Large Close TP 

Control Large Close TP (Low) 

Control Large Close TP (VLow) 

Control Large Open TS 

Control Large Open TS (Low) 

Control Large Open TS (VLow) 

Control Large Open TP 

Control Large Open TP (Low) 

Control Large Open TP (VLow) 

Control Medium Close TS 

Control Medium Close TS (Low) 

Control Medium Close TP 

Control Medium Close TP (Low) 

Control Medium Open TS 

Control Medium Open TS (Low) 

Control Medium Open TP 

Control Medium Open TP (Low) 

Control Small 

Comment 

CBD-40 C TS L D 0.1 F F F F F F F F F F F F F F F F F F F F F F F F 2 2 CBD-41 C TS L D 5 F F F F 115 F F F F F F F F F F F F F F F F F F F FCBD-41B O TS L D 5 F F F F F F F F F F 232 F F F F F F F F F F F F F FCBD-42 C TS M, L L 2.9 34 F 34 F F 34 34 F F F F F F F F F F 34 F F F F F F FCBD-43 C TS M, L L 2.9 F F F F F 18 18 F F F F F F F F F F 18 F F F F F F FCBD-44 C TS M, L D 2.9 F F F F 31 F F F F F F F F F F F 31 F F F F F F F FCBD-45 C TS M, L D 2.9 F F F F 5 F F F F F F F F F F F 5 F F F F F F F FCBD-46 C TS M, L D 2.8 F F F F 45 F F F F F F F F F F F 45 F F F F F F F FCBD-47 C TS M, L L 1.4 F F F F F 40 40 F F F F F F F F F F 40 F F F F F F FCBD-48 O TS M, L D 2.8 F F F F F F F F F F 87 F F F F F F F F F 87 F F F FCBD-49 C TS M, L D 2.8 F F F F 50 F F F F F F F F F F F 50 F F F F F F F FCBD-50 C TS M, L D 1.4 F F F F 1 F F F F F F F F F F F 1 F F F F F F F FCBD-51 O TS M, L L 1.4 F F F F F F F F F F F 31 31 F F F F F F F F 31 F F FCBD-52 O TS M, L D 2.8 F F F F F F F F F F 122 F F F F F F F F F 122 F F F FCBD-53 C TS M, L D 2.8 F F F F 55 F F F F F F F F F F F 55 F F F F F F F FCBD-53B O TS M, L D 2.8 F F F F F F F F F F 85 F F F F F F F F F 85 F F F F

D-9 ____________________________________________________________________________ 

ELECTRICAL CABINET HEAT RELEASE RATE DATA ANALYSIS
Table D-1 

Matrix of Experiments and Cabinet Characteristics

Test ID Characteristics of the Experiments Types of Cabinets (Heat Release Rate of Experiment, kW) 

Doors 

Thermo-set or Thermo-plastic 

Enclosure Size 

Cable Loading 

Fuel Mass (kg) 

Power SWGR & LC TS 

Power SWGR & LC TP 

Power MCC TS 

Power MCC TP 

Control Large Close TS 

Control Large Close TS (Low) 

Control Large Close TS (VLow) 

Control Large Close TP 

Control Large Close TP (Low) 

Control Large Close TP (VLow) 

Control Large Open TS 

Control Large Open TS (Low) 

Control Large Open TS (VLow) 

Control Large Open TP 

Control Large Open TP (Low) 

Control Large Open TP (VLow) 

Control Medium Close TS 

Control Medium Close TS (Low) 

Control Medium Close TP 

Control Medium Close TP (Low) 

Control Medium Open TS 

Control Medium Open TS (Low) 

Control Medium Open TP 

Control Medium Open TP (Low) 

Control Small 

Comment 

CBD-54 O TP M, L N 1.6 F F F F F F F F F F F F F 94 F F F F F F F F 94 F FCBD-55 C TP M, L L 3.1 F F F F F F F F 21 21 F F F F F F F F F 21 F F F F FCBD-56 C TP M, L L 1.7 F F F F F F F F 8 8 F F F F F F F F F 8 F F F F FCBD-57 C TP M, L L 1.7 F F F F F F F F 5 5 F F F F F F F F F 5 F F F F FCBD-58 C TP M, L D 3.4 F F F F F F F 26 F F F F F F F F F F 26 F F F F F FCBD-59 O TP M, L D 3.4 F F F F F F F F F F F F F 22 F F F F F F F F 22 F FCBD-60 C TP M D 7.4 F F F F F F F F F F F F F F F F F F 88 F F F F F FCBD-61 C TS M D 12 F F F F F F F F F F F F F F F F 5 F F F F F F F FCBD-62 C TS M D 12 F F F F F F F F F F F F F F F F 3 F F F F F F F FCBD-63 C TS M D 12 F F F F F F F F F F F F F F F F 92 F F F F F F F FCBD-64 C TS M D 6 6 F F F F F F F F F F F F F F F 6 F F F F F F F FCBD-65 C TS M D 6 7 F F F F F F F F F F F F F F F 7 F F F F F F F FCBD-66 C TP M, L L 3.4 F F F F F F F F 26 26 F F F F F F F F F 26 F F F F FCBD-66B O TP M, L L 3.4 F F F F F F F F F F F F F F 26 26 F F F F F F F 26 FCBD-67 C TP M, L L 3.4 F F F F F F F F 25 25 F F F F F F F F F 25 F F F F FCBD-67B C TP M, L L 3.4 F F F F F F F F 35 35 F F F F F F F F F 35 F F F F F

D-10 ____________________________________________________________________________ 

ELECTRICAL CABINET HEAT RELEASE RATE DATA ANALYSIS
Table D-1 

Matrix of Experiments and Cabinet Characteristics

Test ID Characteristics of the Experiments Types of Cabinets (Heat Release Rate of Experiment, kW) 

Doors 

Thermo-set or Thermo-plastic 

Enclosure Size 

Cable Loading 

Fuel Mass (kg) 

Power SWGR & LC TS 

Power SWGR & LC TP 

Power MCC TS 

Power MCC TP 

Control Large Close TS 

Control Large Close TS (Low) 

Control Large Close TS (VLow) 

Control Large Close TP 

Control Large Close TP (Low) 

Control Large Close TP (VLow) 

Control Large Open TS 

Control Large Open TS (Low) 

Control Large Open TS (VLow) 

Control Large Open TP 

Control Large Open TP (Low) 

Control Large Open TP (VLow) 

Control Medium Close TS 

Control Medium Close TS (Low) 

Control Medium Close TP 

Control Medium Close TP (Low) 

Control Medium Open TS 

Control Medium Open TS (Low) 

Control Medium Open TP 

Control Medium Open TP (Low) 

Control Small 

Comment 

CBD-68 C TP M D 4.5 F F F F F F F 216 F F F F F F F F F F F F F F F F F 3 CBD-69 C TP M D 3.5 10 F F F F F F F F F F F F F F F F F 10 F F F F F FCBD-70 C TS M D 3.1 F F F F 2 F F F F F F F F F F F F F F F F F F F F 3 CBD-71 C TS M D 3.1 F F F F 138 F F F F F F F F F F F F F F F F F F F F 3 CBD-72 C TS M, L L 2.9 5 F 5 F F 5 5 F F F F F F F F F F 5 F F F F F F FCBD-73 C TS M, L D 2.9 4 F 4 F 4 F F F F F F F F F F F 4 F F F F F F F FCBD-74 C TS M, L L 2.4 5 F 5 F F 5 5 F F F F F F F F F F 5 F F F F F F FCBD-75 C TS M, L L 2.9 15 F 15 F F 15 15 F F F F F F F F F F 15 F F F F F F FCBD-76 C TS M, L L 2.9 9 F 9 F F 9 9 F F F F F F F F F F 9 F F F F F F FCBD-77 C TS M, L D 2.4 11 F 11 F 11 F F F F F F F F F F F 11 F F F F F F F FCBD-77B O TS M, L D 2.4 F F F F F F F F F F 17 F F F F F F F F F 17 F F F FCBD-78 C TS M, L D 2.4 F F F F 54 F F F F F F F F F F F 54 F F F F F F F FCBD-79 C TS M, L D 6.1 F F F F 40 F F F F F F F F F F F F F F F F F F F F 3 CBD-79B O TS M, L D 6.1 F F F F F F F F F F 65 F F F F F F F F F F F F F F 3 CBD-80 C TS M, L D 2.8 F F F F 20 F F F F F F F F F F F 20 F F F F F F F FCBD-80B O TS M, L N 2.8 F F F F F F F F F F 100 F F F F F F F F F 100 F F F F

D-11 ____________________________________________________________________________ 

ELECTRICAL CABINET HEAT RELEASE RATE DATA ANALYSIS
Table D-1 

Matrix of Experiments and Cabinet Characteristics

Test ID Characteristics of the Experiments Types of Cabinets (Heat Release Rate of Experiment, kW) 

Doors 

Thermo-set or Thermo-plastic 

Enclosure Size 

Cable Loading 

Fuel Mass (kg) 

Power SWGR & LC TS 

Power SWGR & LC TP 

Power MCC TS 

Power MCC TP 

Control Large Close TS 

Control Large Close TS (Low) 

Control Large Close TS (VLow) 

Control Large Close TP 

Control Large Close TP (Low) 

Control Large Close TP (VLow) 

Control Large Open TS 

Control Large Open TS (Low) 

Control Large Open TS (VLow) 

Control Large Open TP 

Control Large Open TP (Low) 

Control Large Open TP (VLow) 

Control Medium Close TS 

Control Medium Close TS (Low) 

Control Medium Close TP 

Control Medium Close TP (Low) 

Control Medium Open TS 

Control Medium Open TS (Low) 

Control Medium Open TP 

Control Medium Open TP (Low) 

Control Small 

Comment 

CBD-81 C TS M, L L 2.9 24 F 24 F F 24 24 F F F F F F F F F F 24 F F F F F F FCBD-82 C TP M D 7.4 F F F F F F F F F F F F F F F F F F 1 F F F F F FCBD-82B O TP M D 7.4 F F F F F F F F F F F F F F F F F F F F F F 63 F FCBD-83 O TP M D 4.5 F F F F F F F F F F F F F 577 F F F F F F F F F F F 3 CBD-84 O TS L D 3.3 F F F F F F F F F F 37 F F F F F F F F F F F F F FCBD-85 C TS L L 2 F F F F F 2 2 F F F F F F F F F F F F F F F F F FCBD-86 O TS L L 2 F F F F F F F F F F F 19 19 F F F F F F F F F F F FCBD-87 C TS L D 3.3 F F F F 29 F F F F F F F F F F F F F F F F F F F FCBD-88 C TP L D 1.1 F F F F F F F 147 F F F F F F F F F F F F F F F F FCBD-89 C TP L L 1.1 F F F F F F F F 25 25 F F F F F F F F F F F F F F FCBD-90 C TS L L 23 F F F F F 12 12 F F F F F F F F F F F F F F F F F FCBD-91 C TS L L 2.1 F F F F F 3 3 F F F F F F F F F F F F F F F F F FCBD-92 C TS L L 2.1 F F F F F 15 15 F F F F F F F F F F F F F F F F F FCBD-93 C TP L D 3.1 F F F F F F F 59 F F F F F F F F F F F F F F F F FCBD-94 C TS L D 4.9 F F F F 37 F F F F F F F F F F F F F F F F F F F FCBD-95 C TP L L 5.4 F F F F F F F F 30 30 F F F F F F F F F F F F F F F

D-12 ____________________________________________________________________________ 

ELECTRICAL CABINET HEAT RELEASE RATE DATA ANALYSIS
Table D-1 

Matrix of Experiments and Cabinet Characteristics

Test ID Characteristics of the Experiments Types of Cabinets (Heat Release Rate of Experiment, kW) 

Doors 

Thermo-set or Thermo-plastic 

Enclosure Size 

Cable Loading 

Fuel Mass (kg) 

Power SWGR & LC TS 

Power SWGR & LC TP 

Power MCC TS 

Power MCC TP 

Control Large Close TS 

Control Large Close TS (Low) 

Control Large Close TS (VLow) 

Control Large Close TP 

Control Large Close TP (Low) 

Control Large Close TP (VLow) 

Control Large Open TS 

Control Large Open TS (Low) 

Control Large Open TS (VLow) 

Control Large Open TP 

Control Large Open TP (Low) 

Control Large Open TP (VLow) 

Control Medium Close TS 

Control Medium Close TS (Low) 

Control Medium Close TP 

Control Medium Close TP (Low) 

Control Medium Open TS 

Control Medium Open TS (Low) 

Control Medium Open TP 

Control Medium Open TP (Low) 

Control Small 

Comment 

CBD-96 C TP L L 5.4 F F F F F F F F 33 33 F F F F F F F F F F F F F F FCBD-97 C TP L D 4.6 F F F F F F F 5 F F F F F F F F F F F F F F F F FCBD-97B O TP L D 4.6 F F F F F F F F F F F F F 89 F F F F F F F F F F FCBD-98 C TS L D 7.7 F F F F 121 F F F F F F F F F F F F F F F F F F F FCBD-99 O TP L L 3.3 F F F F F F F F F F F F F F 3 3 F F F F F F F F FCBD-100 C TP L D 6.2 F F F F F F F 34 F F F F F F F F F F F F F F F F FCBD-101 C TP L D 6.2 F F F F F F F 66 F F F F F F F F F F F F F F F F FCBD-102 O TS L D 3.6 F F F F F F F F F F 10 F F F F F F F F F F F F F FCBD-103 C TP L D 1.1 F 42 F 42 F F F 42 F F F F F F F F F F F F F F F F FCBD-104 O TP M D 4.5 F F F F F F F F F F F F F F F F F F F F F F 250 F FCBD-105 C TP M D 6.1 F F F F F F F F F F F F F F F F F F 80 F F F F F FCBD-106 C TP M D 6.1 F F F F F F F F F F F F F F F F F F 10 F F F F F FCBD-106B O TP M D 6.1 F F F F F F F F F F F F F F F F F F F F F F 35 F FCBD-107 O TS M D 0.6 F F F F F F F F F F F F F F F F F F F F F F F F 55 2 CBD-108 C TS M D 5.5 F F F F F F F F F F F F F F F F 32 F F F F F F F FCBD-109 C TS M L 6.1 F F F F F F F F F F F F F F F F F 64 F F F F F F F

D-13 ____________________________________________________________________________ 

ELECTRICAL CABINET HEAT RELEASE RATE DATA ANALYSIS
Table D-1 

Matrix of Experiments and Cabinet Characteristics

Test ID Characteristics of the Experiments Types of Cabinets (Heat Release Rate of Experiment, kW) 

Doors 

Thermo-set or Thermo-plastic 

Enclosure Size 

Cable Loading 

Fuel Mass (kg) 

Power SWGR & LC TS 

Power SWGR & LC TP 

Power MCC TS 

Power MCC TP 

Control Large Close TS 

Control Large Close TS (Low) 

Control Large Close TS (VLow) 

Control Large Close TP 

Control Large Close TP (Low) 

Control Large Close TP (VLow) 

Control Large Open TS 

Control Large Open TS (Low) 

Control Large Open TS (VLow) 

Control Large Open TP 

Control Large Open TP (Low) 

Control Large Open TP (VLow) 

Control Medium Close TS 

Control Medium Close TS (Low) 

Control Medium Close TP 

Control Medium Close TP (Low) 

Control Medium Open TS 

Control Medium Open TS (Low) 

Control Medium Open TP 

Control Medium Open TP (Low) 

Control Small 

Comment 

CBD-110 C TP M, L D 2.2 F 7 F 7 F F F 7 F F F F F F F F F F 7 F F F F F FCBD-111 C TP M, L D 3.1 F F F F F F F 50 F F F F F F F F F F 50 F F F F F FCBD-111B O TP M, L D 3.1 F F F F F F F F F F F F F 268 F F F F F F F F 268 F FCBD-112 O TP M, L D 2.2 F F F F F F F F F F F F F 17 F F F F F F F F 17 F F

Comment 1 Classified as Control Large due to the high cable loading Comment 2 Categorized as Control Small due to mass <1 kg Comment 3 Classified as Control Large due to many loose cables that are not neatly bundled 

D-14 ____________________________________________________________________________ 

ELECTRICAL CABINET HEAT RELEASE RATE DATA ANALYSIS
ELECTRICAL CABINET HEAT RELEASE RATE DATA ANALYSIS 

D-15 

1 D.3 Determination of Alpha and Beta for the Gamma 

2 Distributions 

3 For each electrical enclosure classification listed in Appendix D.2, the working group 

4 recommended a probability distribution for the peak heat release rate. The gamma distribution 

5 was selected as the parametric function to represent these distributions. In order to calculate 

6 the gamma distribution parameters, the working group reached consensus on heat release rate 

values representing the 75th and the 98th 7 percentile of a gamma distribution. These values are 

8 provided in Table D-2 for each electrical enclosure classification. The method for calculating 

9 Alpha and Beta from Table D-2 is also provided later in this section. 

10 

Table D-2 

HRR and Gamma Distribution Parameters

Type of 

Cabinet 

Cabinet Characteristics 

HRR (kW), Working 

Group Suggestion 

Gamma distribution 

parameters, best fit 

values 

Doors TS or TP 

Cable 

Loading 75th 98th Alpha Beta 

Power SWGR & 

Load Center 

N/A TS N/A 30 170 0.32 79 

N/A TP N/A 60 170 0.99 44 

Power MCC & 

Charger 

N/A TS N/A 25 130 0.36 57 

N/A TP N/A 50 130 1.21 30 

Control LARGE 

Closed TS Default 50 400 0.23 223 

Closed TS Low 25 200 0.23 111 

Closed TS Very Low 15 75 0.38 32 

Closed TP Default 100 400 0.52 145 

Closed TP Low 50 200 0.52 73 

Closed TP Very Low 25 75 0.88 21 

Open TS Default 100 700 0.26 365 

Open TS Low 50 350 0.26 182 

Open TS Very Low 15 75 0.38 32 

Open TP Default 200 1000 0.38 428 

Open TP Low 100 500 0.38 214 

Open TP Very Low 25 75 0.88 21 

Control 

MEDIUM & 

Inverter 

Closed TS Default 25 200 0.23 111 

Closed TS Low 15 100 0.27 51 

Closed TP Default 50 200 0.52 73 

Closed TP Low 25 100 0.52 36 

Open TS Default 40 325 0.23 182 

Open TS Low 15 150 0.19 92 

Open TP Default 80 325 0.51 119 

Open TP Low 25 150 0.30 72 

Control SMALL N/A N/A N/A 15 45 0.88 12 
ELECTRICAL CABINET HEAT RELEASE RATE DATA ANALYSIS 

D-16 

1 

2 The alpha and beta parameters for the gamma distributions were calculated in Microsoft Excel 

3 using the “Solver” function. As an example, see the screen capture from Microsoft Excel below, 

4 for the case described as “Control Large Closed TS Default”, in which the given values are 50 

kW for the 75th percentile and 400 kW for the 98th 5 percentile. For each HRR value listed in the 

6 spreadsheet in column L, the cumulative distribution of the gamma function is calculated in 

7 column M using the “Gammadist” function. At first, an estimate of alpha=1 and beta=100 is 

8 entered into cells M29 and M30. 

9 

10 

11 Figure D-1 

12 Screen Capture Depicting the Initial Setup in Microsoft Excel for Determining Alpha and 

13 Beta Parameters for the Gamma Distribution 

14 
ELECTRICAL CABINET HEAT RELEASE RATE DATA ANALYSIS 

D-17 

1 The best-fit values of alpha and beta are calculated as follows: 

2  Step 1: Under the “Data” tab, click “Solver” and the following box pops up. Fill in the 

3 boxes as shown and click “Solve”. 

4 

5 

6 Figure D-2 

7 Step 1 in Calculating Alpha and Beta Parameters for the Gamma Distribution Using 

8 Microsoft Excel 

9 

10  Step 2: The following box appears. Click “OK”. 

11 

12 

13 Figure D-3 

14 Step 2 in Calculating Alpha and Beta Parameters for the Gamma Distribution Using 

15 Microsoft Excel 

16 
ELECTRICAL CABINET HEAT RELEASE RATE DATA ANALYSIS 

D-18 

1  Result: The best-fit values of alpha and beta appear in cells M29 and M30, as shown 

2 below. Checking the results shows that indeed the cumulative distribution of HRR=50 

3 kW is 0.75 and the cumulative distribution of 400 kW is 0.98. 

4 

5 

6 Figure D-4 

7 Final Step in Calculating Alpha and Beta Parameters for the Gamma Distribution Using 

8 Microsoft Excel 

9 
ELECTRICAL CABINET HEAT RELEASE RATE DATA ANALYSIS 

D-19 

1 D.4 Data Analysis 

2 This section provides the following information: 

3  Plots depicting: 

4 o The empirical distribution developed using the selected experimental data (red dot-dash 

5 line) as assigned to each electrical enclosure classification. The empirical distributions 

6 depicted in these plots are considered nominal representations of the applicable data. 

7 However, each member of the working group applied their own judgment and may have 

8 included (or excluded) additional tests in informing their opinions. 

9 o The best fit gamma distribution for the experimental data (green dash line). Notice that 

10 this best fit is based on the selected experimental data only for the electrical enclosure 

11 classification. 

12 o The gamma distribution recommended by the working group (blue solid line) for each 

13 electrical enclosure classification. 

14  Plots depicting the experimental data selected as representative of each electrical enclosure 

15 classification. Values above round markers list the test heat release rate value in units of 

16 kW. 

17  For convenience in reviewing this material, tables are provided that list the parameters for 

18 the probability distributions for each of the electrical enclosure classifications discussed in 

19 this section (see Tables D-3 through D-9). The Alpha and Beta columns refer to the 

20 parameters of the Gamma distribution function, and the 75th and 98th columns refer to the 

21 75th and 98th percentile values of the probability distribution in kW. Each table also 

22 specifies whether the distribution applies to open or closed door configuration, thermoset 

23 (including qualified thermoplastic) or unqualified thermoplastic cable insulation, and the 

24 amount of cable loading within the enclosure. 

25 For some of the enclosure classifications, the assigned data sets are strong (many data points) 

26 while others are quite weak (very few data points). Significant differences do exist for certain 

27 cases when the empirical and recommended distributions are compared. In some cases the 

28 final recommended distributions are somewhat more conservative than the nominal data set 

29 while others are less conservative. As suggested earlier, this is because the working group 

30 considered the full range of tests and made decisions as to whether or not the data set fully 

31 represented each classification group. Specific considerations included in the working group 

32 deliberations are described in the sections that follow and include the following general 

33 observations: 

34 

35  In some cases, the working group decided that the selected data set may not have 

36 represented worst-case conditions possible for the given enclosure classification. In 

37 such cases, the working group gave consideration to other test results that might not be 

38 considered fully applicable to the classification group but that could be used to inform the 

39 final decisions regarding the worst-case fire potential. 

40  In other cases, the selected data set may have been found to overstate the fire potential 

41 under more realistic conditions. In these cases, the working group may have discounted 

42 certain test results and did not attempt to fully bound the assigned data set. 

43  In some cases, the data sets are very sparse and provide a poor basis for assignment of 

44 a final profile. In these cases the working group considered the totality of the available 

45 data and consistency with the results for other enclosure classifications. 
ELECTRICAL CABINET HEAT RELEASE RATE DATA ANALYSIS 

D-20 

1  The working group’s recommended distributions were developed as a cohesive and self2 consistent set. In all cases the final recommended distributions were informed, to at 

3 least some degree, based on consistency with the other distributions. Hence, the 

4 recommended distributions reflect both the absolute behavior of each classification 

5 group and the relative behavior anticipated between classification groups. 

6  The distinctions between the TP and TS cable sub-cases follow a similar pattern for 

each classification group. The recommended worst-case 98th 7 percentile values are the 

same for the two sub-cases, but the 75th 8 percentile values for TS cables are half the 

9 value assigned to the corresponding TP cable case (meaning large fires are less likely 

10 given TS cables). This approach reflects previous studies of cable burning (e.g., the 

11 SNL/NRC tests) which have shown that fire spread among cables is a threshold type 

12 behavior; that is, cables are generally resistant to fire spread until a minimum threshold 

13 of energy is reached, after which fire spread begins. TS cables generally have a higher 

14 threshold for fire spread (i.e., it is harder to induce fire spread in TS cables) but tests 

15 also show that once a sustained and growing fire is created, TS cables can burn with an 

16 intensity equivalent to that of TP cables (e.g., compare SNL tests 23 and 24). 

17  A final factor considered in establishing the peak HRR distributions was the level of 

18 electrical energy available within the enclosure under actual operating conditions. Fire 

19 events show that most enclosure ignitions are tied to electrical faults. The working group 

20 agreed that, all other factors being equal, the presence of a higher level of electrical 

21 energy (i.e., voltage and current) would imply a greater potential for more energetic 

22 ignition events, and faster growing fires. While several tests in the available data sets 

23 have used electrical ignition sources, none used higher energy electrical ignition 

24 sources. As a result, for some of the non-control enclosure classification groups the 

working group chose to extend the 98th 25 percentile (worst-case) fire conditions somewhat 

26 to reflect the higher energy levels present compared to the applicable data sets. 

27 D.4.1 Switchgears and Load Centers 

28 Switchgears and load centers were identified as one classification because of their functionality, 

29 which allows for a relatively easy process for identifying the electrical enclosure and assigning a 

30 peak heat release rate probability distribution. It should be noted that heat release rate profiles 

31 for switchgears and load centers have not been explicitly tested in any of the available 

32 experimental programs. The assessment of the probability distributions for the peak heat 

33 release rate was based on a comparison between the cable configuration in these types of 

34 enclosures, as depicted in numerous pictures inspected by the working group, and the 

35 experimental configuration of the different test series. In general terms, the working group 

36 agreed that these types of enclosures are characterized by relatively low cable loading 

37 dominated by larger diameter power cables. Therefore, the assessment is based mostly on 

38 using tests with lower cable loads and vertical electrical enclosures (i.e., no benchboard type 

39 enclosures) and with tightly bundled cables, as depicted in Figure D-5 and Figure D-6. 

40 

41 For the case of TS cable, the working group assessment is close to the empirical distribution 

42 developed for the selected fire tests (see the solid blue line in Figure D-5). The data sample 

43 applicable to this classification includes peak heat release rate values ranging from 0 kW to 82 

kW. Specifically, the working group assessment for the 75th 44 percentile is very close to the data 

45 sample selected and given the lack of specific testing for these types of cabinets a longer tail for 

the 98th 46 percentile was selected based on the energy available in these enclosures when 

47 energized. In addition, some of the working group members considered tests with higher heat 

48 release rates as applicable to this classification. For example, members may have considered 

49 tests having tight cable bundle arrangements with a relatively high energy ignition source. This 
ELECTRICAL CABINET HEAT RELEASE RATE DATA ANALYSIS 

D-21 

influences the selection of the 98th 1 percentile to ensure a potential fire intensity is captured in 

2 the distribution. 

3 

4 In the case of TP cable content, there is a very small set of data given the loading configuration 

5 and cable material of the tests. The data sample applicable to this classification includes peak 

6 heat release rate values ranging from 7 kW to 42 kW. Therefore the recommended distribution 

7 had to be informed by other electrical enclosure classifications. For example, the working group 

agreed that the 75th 8 percentile should be larger than the equivalent classification for the TS 

9 cable (i.e., 30 kW for TS and 60 kW for TP cables). In addition, given the relatively low cable 

loading of these enclosures in the plant configurations, the working group agreed that the 98th 10 

11 percentile for both TP and TS were equivalent (i.e., 170 kW). 

12 

13 Table D-3 

14 Working Group Recommended Distributions for Switchgears and Load Centers 

Classification Doors

Cable

Material

Cable

Loading Alpha Beta   75th (kW) 98th (kW)

SWGR & Load

Center

N/A TS N/A 0.32 79 30 170

N/A TP N/A 0.99 44 60 170

Figure D-5 

Power Switchgear and Load Center TS. Values above round markers list the test heat 

release rate value in units of kW. 

15 

 

Figure D-6 

Power Switchgear and Load Center TP. Values above round markers list the test heat 

release rate value in units of kW. 

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

0 50 100 150 200 250 300

HRR (kW)

Cumulative Distribution Functions

WG Recommendation Empirical Data Fit

24 27

77 82

3 0 4

34

6 7 10 5 4 5

15 9 11

24

SNL‐ST1SNL‐ST2SNL‐ST3SNL‐ST4

CBD‐15CBD‐17CBD‐21CBD‐42CBD‐64CBD‐65CBD‐69CBD‐72CBD‐73CBD‐74CBD‐75CBD‐76CBD‐77CBD‐81

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

0 50 100 150 200 250 300

HRR (kW)

Cumulative Distribution Functions

WG Recommendation Empirical Data Fit

42

7

CBD‐103CBD‐110
ELECTRICAL CABINET HEAT RELEASE RATE DATA ANALYSIS 

D-22 

1 D.4.2 Motor Control Centers 

2 As is the case with switchgears and load centers, the heat release rate profiles for motor control 

3 centers have not been explicitly tested. A classification for motor control centers was developed 

4 due to its characteristic functionality and common usage in NPPs. The assessment of the 

5 probability distributions for the peak heat release rate was based on a comparison between the 

6 cable configuration in these types of enclosures, as depicted in numerous pictures inspected by 

7 the working group, and the experimental configuration of the different test series. In general 

8 terms, the working group agreed that these types of enclosures are characterized by relatively 

9 low cable loading but also by a cable loading dominated by smaller power and control cables 

10 (e.g., as compared to switchgear and load centers). Therefore, the assessment is based mostly 

11 on using tests with lower cable loads and vertical electrical enclosures (i.e., no benchboard type 

12 enclosures). The working group identified the relatively narrow vertical risers adjacent to the 

13 breaker cubicles routing cables along the height of the motor control center as a key factor. 

14 This configuration characteristic (i.e., fire spread into the vertical riser) was considered in 

15 developing the probability distributions, which are depicted in Figure D-7 and Figure D-8. 

16 

17 For the case of TS cable, the working group assessment is close to the empirical distribution 

18 developed for the selected fire events. The data sample applicable to this classification includes 

19 peak heat release rate values ranging from 0 kW to 82 kW (see Figure D-7). Specifically, the 

working group assessment for the 75th 20 percentile is very close to the data sample selected and 

given the lack of specific testing for these types of cabinets a longer tail for the 98th 21 percentile 

22 was selected based on the energy available in these enclosures when energized. In addition, 

23 some of the working group members considered tests with higher heat release rates as 

24 applicable to this classification (e.g., a given test may have had tight cable bundle arrangements 

with a relatively high energy ignition source), which influenced the selection of the 98th 25 

26 percentile to ensure a potential fire intensity is captured in the distribution. 

27 

28 In the case of TP cable content, there is a very small set of data given the loading configuration 

29 and cable material of the tests. The data sample applicable to this classification includes peak 

30 heat release rate values ranging from 7 kW to 42 kW (Figure D-8). Therefore the recommended 

31 distribution had to be informed by other electrical enclosure classifications. For example, the 

working group agreed that the 75th 32 percentile should be larger than the equivalent classification 

33 for the TS cable. In addition, given the relatively low cable loading of these enclosures in the 

plant configurations, the working group agreed that the 98th 34 percentile values for both TP and 

35 TS were equivalent. 

36 

37 Table D-4 

38 Working Group Recommended Distributions for Motor Centers 

Classification Doors

Cable

Material

Cable

Loading Alpha Beta 75th (kW) 98th (kW)

MCC & Battery

Chargers

N/A TS N/A 0.36 57 25 130

N/A TP N/A 1.21 30 50 130

 
ELECTRICAL CABINET HEAT RELEASE RATE DATA ANALYSIS 

D-23 

 

Figure D-7 

Power MCC and Charger TS. Values above round markers list the test heat release rate 

value in units of kW. 

1 

 

Figure D-8 

Power MCC and Charger TP. Values above round markers list the test heat release rate 

value in units of kW. 

2 D.4.3 Control Large Closed Electrical Enclosures 

3 Due to the wide range of cable configurations associated with control cabinets, this classification 

4 includes six probability distributions to account for the total cable/fuel content and the type of 

5 cables in the electrical enclosure. For the case of closed large control panels with TS cable, the 

6 peak heat release rate in the applicable data ranges from 1 kW to 138 kW as depicted in Figure 

7 D-9, Figure D-10, and Figure D-11. The Default, Low, and Very Low fuel loading distributions 

8 recommended by the working group are close to the empirical distributions resulting from 

plotting the applicable data. In addition, the working group extended the 98th 9 percentile in the 

10 Default case to 400 kW to account for potential configurations that may include combustible 

11 loading other than cables (e.g., circuit cards, etc.) and/or the recognition that once ignited, TS 

12 and TP cables could produce similar heat release rate values. Test 1 from VTT test series 186 

and Test 4 from VTT test series 521 were used to inform the selection of the 98th 13 percentile 

14 value. That test may overstate the fire potential due to the arrangement of fuel near the 

15 electrical ignition point. Hence the final distributions for these two classifications represent, to 

16 some extent, a blending of the two data sets. That is, the working group agreed that the worst17 case potential is similar for TS and TP cables to ignite but that TP cables spread fire more 

easily. The distributions for Low and Very Low fuel loading include 98th 18 percentiles within the 

19 applicable data range. 

20 

21 For the case of TP cable, the peak heat release rate values in the applicable data range from 0 

22 kW to 400 kW as depicted in Figure D-12, Figure D-13, and Figure D-14. Given the “closed 

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

0 50 100 150 200 250 300

HRR (kW)

Cumulative Distribution Functions

WG Recommendation Empirical Data Fit

24 27

77 82

3 0 4

34

5 4 5

15 9 11

24

SNL‐ST1SNL‐ST2SNL‐ST3SNL‐ST4

CBD‐15CBD‐17CBD‐21CBD‐42CBD‐72CBD‐73CBD‐74CBD‐75CBD‐76CBD‐77CBD‐81

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

0 50 100 150 200 250 300

HRR (kW)

Cumulative Distribution Functions

WG Recommendation Empirical Data Fit

42

7

CBD‐103CBD‐110
ELECTRICAL CABINET HEAT RELEASE RATE DATA ANALYSIS 

D-24 

cabinet” configuration, the working group agreed to maintain the 98th 1 percentiles assigned 

earlier to TS cables and to increase the 75th 2 percentiles of the distribution to account for the 

3 increased fire hazard associated with TP cable. 

4 

5 Table D-5 

6 Working Group Recommended Distributions for Large Control Enclosures with Closed Doors 

Classification Doors

Cable

Material

Cable

Loading Alpha Beta 75th (kW) 98th (kW)

Control Large

Closed TS Default 0.23 223 50 400

Closed TS Low 0.23 111 25 200

Closed TS Very Low 0.38 32 15 75

Closed TP Default 0.52 145 100 400

Closed TP Low 0.52 73 50 200

Closed TP Very Low 0.88 21 25 75

7 

 

Figure D-9 

Control Large Closed TS-Default. Values above round markers list the test heat release 

rate value in units of kW. 

8 

 

Figure D-10 

Control Large Closed TS-Low. Values above round markers list the test heat release rate 

value in units of kW. 

9 

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

0 100 200 300 400 500 600

HRR (kW)

Cumulative Distribution Functions

WG Recommendation Empirical Data Fit

95 93

50

35

115

31

5

45 50

1

55

2

138

4 11

54

40

20 29 37

121

SNL‐ST7SNL‐ST8

CBD‐33CBD‐34CBD‐41CBD‐44CBD‐45CBD‐46CBD‐49CBD‐50CBD‐53CBD‐70CBD‐71CBD‐73CBD‐77CBD‐78CBD‐79CBD‐80CBD‐87CBD‐94CBD‐98

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

0 100 200 300 400 500 600

HRR (kW)

Cumulative Distribution Functions

WG Recommendation Empirical Data Fit

3 5 4 4

34

18

40

5 5

15

9

24

2

12

3

15

CBD‐19CBD‐20CBD‐21CBD‐22CBD‐42CBD‐43CBD‐47CBD‐72CBD‐74CBD‐75CBD‐76CBD‐81CBD‐85CBD‐90CBD‐91CBD‐92
ELECTRICAL CABINET HEAT RELEASE RATE DATA ANALYSIS 

D-25 

 

Figure D-11 

Control Large Closed TS-Very Low. Values above round markers list the test heat release 

rate value in units of kW. 

1 

 

Figure D-12 

Control Large Closed TP-Default. Values above round markers list the test heat release 

rate value in units of kW. 

2 

 

Figure D-13 

Control Large Closed TP-Low. Values above round markers list the test heat release rate 

value in units of kW. 

3 

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

0 100 200 300 400 500 600

HRR (kW)

Cumulative Distribution Functions

WG Recommendation Empirical Data Fit

3 5 4 4

34

18

40

5 5

15

9

24

2

12

3

15

CBD‐19CBD‐20CBD‐21CBD‐22CBD‐42CBD‐43CBD‐47CBD‐72CBD‐74CBD‐75CBD‐76CBD‐81CBD‐85CBD‐90CBD‐91CBD‐92

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

0 100 200 300 400 500 600

HRR (kW)

Cumulative Distribution Functions

WG Recommendation Empirical Data Fit

280

185

400

50

0

200180

0 0

120100

175

0 0

125100

400

50

0

200

26

216

147

59

5 34

66 42

7

50

SNL‐...SNL‐...

VTT18...VTT18...VTT18...VTT18...VTT26...VTT26...VTT26...VTT26...VTT26...VTT52...VTT52...VTT52...VTT52...VTT52...VTT52...VTT52...VTT52...VTT52...

CBD‐58CBD‐68CBD‐88CBD‐93CBD‐97

CBD‐100CBD‐101CBD‐103CBD‐110CBD‐111

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

0 100 200 300 400 500 600

HRR (kW)

Cumulative Distribution Functions

WG Recommendation Empirical Data Fit

21

8

5

26 25

35

25

30

33

CBD‐55CBD‐56CBD‐57CBD‐66CBD‐67

CBD‐67B

CBD‐89CBD‐95CBD‐96
ELECTRICAL CABINET HEAT RELEASE RATE DATA ANALYSIS 

D-26 

 

Figure D-14 

Control Large Closed TP-Very Low. Values above round markers list the test heat release 

rate value in units of kW. 

1 D.4.4 Control Large Open Electrical Enclosures 

2 The large open control TS and TP classifications are associated with two of the largest 

3 experimental data sets. For the case of TS cable, one of the SNL tests (i.e., Test 23) was 

4 removed due to the large ignition source, which is not representative of ignition sources within 

5 electrical enclosures in commercial nuclear power plants. The TP data set does include two 

6 very large fire tests (SNL Test 24 and SNL Test 25). The TS applicable data ranges from 0 kW 

7 to 232 kW, as depicted in Figure D-15, Figure D-16, and Figure D-17. The TP applicable data 

8 ranges from 3 kW to 1300 kW, as depicted in Figure D-18, Figure D-19, and Figure D-20. 

9 In general, the distributions recommended by the working group are close to the empirical ones. 

10 The only exception is the Default distribution for open cabinets with TP cable. Recall the 

11 discussion for large cabinets earlier (i.e., the working group discounted the effects of Tests 24 

12 and 25 because of the nature of fuel immediately adjacent to the ignition source). Therefore the 

13 empirical data suggests higher heat release rates than what the working group recommended 

14 for this classification. 

15 

16 Table D-6 

17 Working Group Recommended Distributions for Large Control Enclosures with Open Doors 

Classification Doors

Cable

Material

Cable

Loading Alpha Beta 75th (kW) 98th (kW)

Control Large

Open TS Default 0.26 365 100 700

Open TS Low 0.26 182 50 350

Open TS Very Low 0.38 32 15 75

Open TP Default 0.38 428 200 1000

Open TP Low 0.38 214 100 500

Open TP Very Low 0.88 21 25 75

18 

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

0 100 200 300 400 500 600

HRR (kW)

Cumulative Distribution Functions

WG Recommendation Empirical Data Fit

21

8

5

26 25

35

25

30

33

CBD‐55CBD‐56CBD‐57CBD‐66CBD‐67

CBD‐67B

CBD‐89CBD‐95CBD‐96
ELECTRICAL CABINET HEAT RELEASE RATE DATA ANALYSIS 

D-27 

 

Figure D-15 

Control Large Open TS-Default. Values above round markers list the test heat release rate 

value in units of kW. 

1 

 

Figure D-16 

Control Large Open TS-Low. Values above round markers list the test heat release rate 

value in units of kW. 

2 

 

Figure D-17 

Control Large Open TS-Very Low. Values above round markers list the test heat release 

rate value in units of kW. 

3 

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

0 200 400 600 800 1000

HRR (kW)

Cumulative Distribution Functions

WG Recommendation Empirical Data Fit

24 27

77 82 82 74

56

215

232

87

122

85

17

65

100

37

10

SNL‐ST1

SNL‐ST2

SNL‐ST3

SNL‐ST4

SNL‐ST6

SNL‐ST9

SNL‐PCT3SNL‐PCT6

CBD‐41B

CBD‐48CBD‐52

CBD‐53B

CBD‐77B

CBD‐79B

CBD‐80B

CBD‐84

CBD‐102

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

0 200 400 600 800 1000

HRR (kW)

Cumulative Distribution Functions

WG Recommendation Empirical Data Fit

3 2 0

31

19

CBD‐15CBD‐16CBD‐17CBD‐51CBD‐86

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

0 200 400 600 800 1000

HRR (kW)

Cumulative Distribution Functions

WG Recommendation Empirical Data Fit

3 2 0

31

19

CBD‐15CBD‐16CBD‐17CBD‐51CBD‐86
ELECTRICAL CABINET HEAT RELEASE RATE DATA ANALYSIS 

D-28 

 

Figure D-18 

Control Large Open TP-Default. Values above round markers list the test heat release rate 

value in units of kW. 

1 

 

Figure D-19 

Control Large Open TP-Low. Values above round markers list the test heat release rate 

value in units of kW. 

2 

 

Figure D-20 

Control Large Open TP-Very Low. Values above round markers list the test heat release 

rate value in units of kW. 

3 D.4.5 Control Medium Closed Electrical Enclosures 

4 Due to the wide range of cable configurations associated with control cabinets, this classification 

5 includes four probability distributions to account for the cable content, ventilation conditions, and 

6 type of cables in the electrical enclosures. For the case of closed medium control panels with 

7 TS cable, the peak heat release rates in the applicable data range from 1 kW to 169 kW as 

8 depicted in Figure D-21 and Figure D-22. The Default and Low distributions recommended by 

9 the working group are close to the empirical distributions resulting from plotting the applicable 

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

0 200 400 600 800 1000 1200

HRR (kW)

Cumulative Distribution Functions

WG Recommendation Empirical Data Fit

132

506

791

1300

840

94 22

577

89

268

17

SNL‐ST5

SNL‐ST11

SNL‐PCT5

SNL‐

Test24

SNL‐

Test25

CBD‐54CBD‐59CBD‐83

CBD‐97B

CBD‐

111B

CBD‐112

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

0 200 400 600 800 1000 1200

HRR (kW)

Cumulative Distribution Functions

WG Recommendation Empirical Data Fit

3

18

26

3

CBD‐18CBD‐23

CBD‐66B

CBD‐99

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

0 200 400 600 800 1000 1200

HRR (kW)

Cumulative Distribution Functions

WG Recommendation Empirical Data Fit

3

18

26

3

CBD‐18CBD‐23

CBD‐66B

CBD‐99
ELECTRICAL CABINET HEAT RELEASE RATE DATA ANALYSIS 

D-29 

1 data. In addition, the working group agreed that the data set might not include potential worstcase conditions and decided to extend the 98th 2 percentile in the Default case to 200 kW to 

3 account for potential configurations not included in the experimental programs. CBD Test 38 

4 produced a peak heat release rate of 169 kW, which was used by the working group to inform 

the selection of the 98th percentile. The distribution for Low include 98th 5 percentiles within the 

6 applicable data range. 

7 

8 For the case of TP cable, the peak heat release rate values in the applicable data range from 1 

9 kW to 88 kW as depicted in Figure D-23 and Figure D-24. Given the “closed cabinet” 

configuration, the working group agreed to maintain the 98th 10 percentiles assigned earlier to TS 

cables and to increase the 75th 11 percentiles of the distribution to account for the increased fire 

12 hazard associated with TP cable. This was based in part on having a limited set of applicable 

13 data for medium panels with TP cable. 

14 

15 Table D-7 

16 Working Group Recommended Distributions for Medium Control Enclosures with Closed 

17 Doors 

Classification Doors

Cable

Material

Cable

Loading Alpha Beta 75th (kW) 98th (kW)

Control Medium

Closed TS Default 0.23 111 25 200

Closed TS Low 0.27 51 15 100

Closed TP Default 0.52 73 50 200

Closed TP Low 0.52 36 25 100

18 

 

Figure D-21 

Medium Closed TS-Default. Values above round markers list the test heat release rate 

value in units of kW. 

19 

20 

21 

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

0 200 400 600 800 1000 1200

HRR (kW)

Cumulative Distribution Functions

WG Recommendation Empirical Data Fit

52

4 111

82 72

50

35

4

35

169

60

31

5

45 50

1

55

5 3

92

6 7 4 11

54

20

32

CBD‐12CBD‐25CBD‐26CBD‐27CBD‐28CBD‐29CBD‐30CBD‐33CBD‐34CBD‐36CBD‐37CBD‐38CBD‐39CBD‐44CBD‐45CBD‐46CBD‐49CBD‐50CBD‐53CBD‐61CBD‐62CBD‐63CBD‐64CBD‐65CBD‐73CBD‐77CBD‐78CBD‐80

CBD‐108
ELECTRICAL CABINET HEAT RELEASE RATE DATA ANALYSIS 

D-30 

 

Figure D-22 

Control Medium Closed TS-Low. Values above round markers list the test heat release 

rate value in units of kW. 

1 

 

Figure D-23 

Control Medium Closed TP-Default. Values above round markers list the test heat release 

rate value in units of kW. 

2 

 

Figure D-24 

Control Medium Closed TP-Low. Values above round markers list the test heat release 

rate value in units of kW. 

3 D.4.6 Control Medium Open Electrical Enclosures 

4 Due to the wide range of cable configurations associated with control cabinets, this classification 

5 includes four probability distributions to account for the total cable/fuel content and type of 

6 cables in the electrical enclosures. For the case of closed medium control panels with TS cable, 

7 the peak heat release rates in the applicable data set range from 0 kW to 146 kW as depicted in 

8 Figure D-25 and Figure D-26. The Default and Low distributions recommended by the working 

9 group are close to the empirical distributions resulting from plotting the applicable data. In 

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

0 50 100 150 200 250 300

HRR (kW)

Cumulative Distribution Functions

WG Recommendation Empirical Data Fit

3 5 4 4

34

18

40

5 5

15

9

24

64

CBD‐19CBD‐20CBD‐21CBD‐22CBD‐42CBD‐43CBD‐47CBD‐72CBD‐74CBD‐75CBD‐76CBD‐81

CBD‐109

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

0 50 100 150 200 250 300

HRR (kW)

Cumulative Distribution Functions

WG Recommendation Empirical Data Fit

26

88

10

1

80

10 7

50

CBD‐58CBD‐60CBD‐69CBD‐82

CBD‐105CBD‐106CBD‐110CBD‐111

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

0 50 100 150 200 250 300

HRR (kW)

Cumulative Distribution Functions

WG Recommendation Empirical Data Fit

21

8

5

26 25

35

CBD‐55CBD‐56CBD‐57CBD‐66CBD‐67

CBD‐67B
ELECTRICAL CABINET HEAT RELEASE RATE DATA ANALYSIS 

D-31 

1 addition, the working group agreed to inform the distribution based on the corresponding TP 

cable cases and extended the 98th 2 percentile in the Default case to 200 kW to account for 

3 potential configurations not included in the experimental programs. In addition, the working 

group extended the 98th 4 percentile in the Default case to 325 kW to account for potential 

5 configurations that may include combustible loading other than cables (e.g., circuit cards, etc.) 

6 and/or the recognition that once ignited, TS and TP cables could produce similar heat release 

7 rate values. Test CBD 111B, which resulted in a peak heat release rate of 268 kW, was used to 

inform the selection of the 98th 8 percentile value. 

9 

10 That is, the working group agreed that the worst-case potential cables ignite and spread fire 

more easily. The distribution for Low include 98th 11 percentiles within the applicable data range. 

12 For the case of TP cable, peak heat release rate values in the applicable data range from 3 kW 

13 to 268 kW as depicted in Figure D-27 and Figure D-28. Given the “closed cabinet” 

configuration, the working group agreed to maintain the 98th 14 percentiles assigned earlier to TS 

cables and to increase the 75th 15 percentiles of the distribution to account for the increased fire 

16 hazard associated with TP cable. 

17 

18 Table D-8 

19 Working Group Recommended Distributions for Medium Control Enclosures with Open 

20 Doors 

Classification Doors

Cable

Material

Cable

Loading Alpha Beta 75th (kW) 98th (kW)

Control Medium

Open TS Default 0.23 182 40 325

Open TS Low 0.19 92 15 150

Open TP Default 0.51 119 80 325

Open TP Low 0.30 72 25 150

21 

 

Figure D-25 

Medium Open TS-Default. Values above round markers list the test heat release rate value 

in units of kW. 

22 

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

0 100 200 300 400 500 600

HRR (kW)

Cumulative Distribution Functions

WG Recommendation Empirical Data Fit

24 27

77 82

1 10

146

87

122

85

17

100

SNL‐ST1SNL‐ST2SNL‐ST3SNL‐ST4

CBD‐11

CBD‐28B

CBD‐35CBD‐48CBD‐52

CBD‐53BCBD‐77BCBD‐80B
ELECTRICAL CABINET HEAT RELEASE RATE DATA ANALYSIS 

D-32 

 

Figure D-26 

Control Medium Open TS-Low. Values above round markers list the test heat release rate 

value in units of kW. 

1 

 

Figure D-27 

Control Medium Open TP-Default. Values above round markers list the test heat release 

rate value in units of kW. 

2 

 

Figure D-28 

Control Medium Open TP-Low. Values above round markers list the test heat release rate 

value in units of kW. 

3 D.4.7 Control Medium/Very Low and Small Electrical Enclosures 

4 Small control electrical enclosures were not specifically tested in the available experimental 

5 programs. Consequently, the working group agreed on one peak heat release rate distribution 

6 based on available tests consisting of relatively low cable loading and cases of higher fuel 

7 loading where little or no fire spread was observed. This data set includes those tests in the 

8 NIST/NRC set that used the 1 kW and 5 KW electrical ignition source, which generally failed to 

9 induce fire spread. The applicable data, as depicted in Figure D-29, includes peak heat release 

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

0 100 200 300 400 500 600

HRR (kW)

Cumulative Distribution Functions

WG Recommendation Empirical Data Fit

3 2 0

31

CBD‐15CBD‐16CBD‐17CBD‐51

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

0 100 200 300 400 500 600

HRR (kW)

Cumulative Distribution Functions

WG Recommendation Empirical Data Fit

132

94

22

63

250

35

268

17

SNL‐ST5

CBD‐54CBD‐59

CBD‐82B

CBD‐104

CBD‐

106B

CBD‐

111B

CBD‐112

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

0 100 200 300 400 500 600

HRR (kW)

Cumulative Distribution Functions

WG Recommendation Empirical Data Fit

3

18

26

CBD‐18CBD‐23

CBD‐66B
ELECTRICAL CABINET HEAT RELEASE RATE DATA ANALYSIS 

D-33 

1 rate values ranging from 0 kW to 55 kW. The working group agreed that the fire intensities 

2 observed from these enclosures should be small, and that the data set likely overstated the fire 

3 potential for small electrical enclosures with such limited fuel loads. The working group 

therefore agreed on a 75th 4 percentile value of 15 kW. The distribution recommended by the 

5 working group is close to the empirical one developed directly from the applicable data set. 

6 

7 Table D-9 

8 Working Group Recommended Distributions for Small Control Enclosures 

Classification Doors

Cable

Material

Cable

Loading Alpha Beta 75th (kW) 98th (kW)

Control Small N/A N/A N/A 0.88 12 15 45

9 

10 

 

Figure D-29 

Control Small. Values above round markers list the test heat release rate value in units of 

kW. 

11 

12 

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

0 20 40 60 80 100

HRR (kW)

Cumulative Distribution Functions

WG Recommendation Empirical Data Fit

35

20

40

20

2222 1 2

9

0 1 1 2 4 4

28

6

2

55

VTT521...VTT521...VTT521...VTT521...

CBD‐1CBD‐2CBD‐3CBD‐4CBD‐5CBD‐6CBD‐7CBD‐8CBD‐9

CBD‐10CBD‐13CBD‐14CBD‐24CBD‐31CBD‐32CBD‐40

CBD‐107

E-1

1 Appendix E

2 Obstructed Plume Fire Modeling Results 

3 

4 This appendix presents the results of the FDS computer simulations related to the obstructed 

5 plume studies. Table E-1 and Table E-2 list the results of obstructed and unobstructed plume 

6 simulations, respectively. Table E-3, Table E-4, Table E-5, Table E-6, Table E-7, Table E-8 and 

7 Table E-9 present the results of bias and uncertainty, opening sensitivity, vertical source 

8 sensitivity, wall surface sensitivity, soffit sensitivity, steel enclosure thickness, and horizontal 

9 plume shift and angle results for the obstructed plume models, respectively. Table E-10 

10 presents a table identifying the FDS run identification numbers associated with the unobstructed 

11 (baseline) plume case (in Table E-2) and three obstructed plume cases (in Table E-1) so that 

12 one could compare the results of the similar experimental configurations. Finally, Table E-11 

13 presents a matrix of simulation runs in Table E-4 for ease of use on the opening sensitivity 

14 study. The fire models used for the simulations, the input data files, and a copy of NUREG-1934 

15 (EPRI 1023259), Nuclear Power Plant Fire Modeling Analysis Guidelines (NPP FIRE MAG), are 

16 attached to this report. 

17 Subject Page 

18 Table E-1: Obstructed Simulation Results ........................................................................ E-2 

19 Table E-2: Unobstructed Simulation Results .................................................................. E-83 

20 Table E-3: Determination of Bias and Uncertainty ....................................................... E-109 

21 Table E-4: Opening Sensitivity Cases ............................................................................ E-124 

22 Table E-5: Vertical Source Sensitivity Results .............................................................. E-135 

23 Table E-6: Wall Surface Source Sensitivity Results ..................................................... E-139 

24 Table E-7: Soffit Sensitivity Results ............................................................................... E-142 

25 Table E-8: Thickness of Steel Enclosure Sensitivity Results ...................................... E-149 

26 Table E-9: Horizontal Plume Shift and Angle Sensitivity Results ................................ E-156 

27 Table E-10: Index to Obstructed and Unobstructed Simulation Numbers ................. E-171 

28 Table E-11: Index to Opening Sensitivity Simulation Numbers ................................... E-173 

29 
Obstructed Simulation Results 

Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

ARCH_1054 1000 0.91 0.30 2.4 402.99 BASE_404 TRUE Source Located 1 ft. above Ground

ARCH_1054 1000 0.91 0.30 2.7 249.05 BASE_404 TRUE Source Located 1 ft. above GroundARCH_1054 1000 0.91 0.30 3 199.53 BASE_404 TRUE Source Located 1 ft. above GroundARCH_1054 1000 0.91 0.30 3.3 172.57 BASE_404 TRUE Source Located 1 ft. above GroundARCH_1054 1000 0.91 0.30 3.6 153.99 BASE_404 TRUE Source Located 1 ft. above GroundARCH_1054 1000 0.91 0.30 3.9 136.7 BASE_404 TRUE Source Located 1 ft. above GroundARCH_1054 1000 0.91 0.30 4.2 126.62 BASE_404 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_1054 1000 0.91 0.30 4.5 113.14 BASE_404 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_1054 1000 0.91 0.30 4.8 103.21 BASE_404 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_1054 1000 0.91 0.30 5.1 96.109 BASE_404 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_1054 1000 0.91 0.30 5.4 90.815 BASE_404 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_1054 1000 0.91 0.30 5.7 85.55 BASE_404 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_1054 1000 0.91 0.30 6 81.415 BASE_404 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_1055 1000 0.91 1.14 2.4 706.62 BASE_400 FALSE Not FilteredARCH_1055 1000 0.91 1.14 2.7 459.45 BASE_400 FALSE Not FilteredARCH_1055 1000 0.91 1.14 3 337.19 BASE_400 FALSE Not Filtered

E-2 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

ARCH_1055 1000 0.91 1.14 3.3 271.35 BASE_400 FALSE Not Filtered

ARCH_1055 1000 0.91 1.14 3.6 227.5 BASE_400 FALSE Not FilteredARCH_1055 1000 0.91 1.14 3.9 201.32 BASE_400 FALSE Not FilteredARCH_1055 1000 0.91 1.14 4.2 178.36 BASE_400 FALSE Not FilteredARCH_1055 1000 0.91 1.14 4.5 159.08 BASE_400 FALSE Not FilteredARCH_1055 1000 0.91 1.14 4.8 143.06 BASE_400 FALSE Not FilteredARCH_1055 1000 0.91 1.14 5.1 128.93 BASE_400 TRUE Temperature < 130 CARCH_1055 1000 0.91 1.14 5.4 111.59 BASE_400 TRUE Temperature < 130 CARCH_1055 1000 0.91 1.14 5.7 101.23 BASE_400 TRUE Temperature < 130 CARCH_1055 1000 0.91 1.14 6 94.488 BASE_400 TRUE Temperature < 130 CARCH_1056 1000 0.91 1.98 2.4 1071 BASE_401 TRUE Temperature > 800 CARCH_1056 1000 0.91 1.98 2.7 999.09 BASE_401 TRUE Temperature > 800 CARCH_1056 1000 0.91 1.98 3 888.05 BASE_401 TRUE Temperature > 800 CARCH_1056 1000 0.91 1.98 3.3 744.08 BASE_401 FALSE Not FilteredARCH_1056 1000 0.91 1.98 3.6 623.99 BASE_401 FALSE Not FilteredARCH_1056 1000 0.91 1.98 3.9 505.27 BASE_401 FALSE Not FilteredARCH_1056 1000 0.91 1.98 4.2 404.48 BASE_401 FALSE Not FilteredARCH_1056 1000 0.91 1.98 4.5 327.37 BASE_401 FALSE Not FilteredARCH_1056 1000 0.91 1.98 4.8 279.4 BASE_401 FALSE Not FilteredARCH_1056 1000 0.91 1.98 5.1 243.14 BASE_401 FALSE Not FilteredARCH_1056 1000 0.91 1.98 5.4 217.29 BASE_401 FALSE Not Filtered

E-3 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

ARCH_1056 1000 0.91 1.98 5.7 197.62 BASE_401 FALSE Not Filtered

ARCH_1056 1000 0.91 1.98 6 181.65 BASE_401 FALSE Not FilteredARCH_1063 1000 1.22 0.30 2.4 314.81 BASE_405 TRUE Source Located 1 ft. above GroundARCH_1063 1000 1.22 0.30 2.7 200.08 BASE_405 TRUE Source Located 1 ft. above GroundARCH_1063 1000 1.22 0.30 3 161.99 BASE_405 TRUE Source Located 1 ft. above GroundARCH_1063 1000 1.22 0.30 3.3 139.11 BASE_405 TRUE Source Located 1 ft. above GroundARCH_1063 1000 1.22 0.30 3.6 127.87 BASE_405 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_1063 1000 1.22 0.30 3.9 116.51 BASE_405 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_1063 1000 1.22 0.30 4.2 108.46 BASE_405 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_1063 1000 1.22 0.30 4.5 101.39 BASE_405 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_1063 1000 1.22 0.30 4.8 97.629 BASE_405 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_1063 1000 1.22 0.30 5.1 92.41 BASE_405 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_1063 1000 1.22 0.30 5.4 86.168 BASE_405 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_1063 1000 1.22 0.30 5.7 80.069 BASE_405 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_1063 1000 1.22 0.30 6 77.021 BASE_405 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_1064 1000 1.22 1.14 2.4 518.48 BASE_402 FALSE Not Filtered

E-4 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

ARCH_1064 1000 1.22 1.14 2.7 310.87 BASE_402 FALSE Not Filtered

ARCH_1064 1000 1.22 1.14 3 248.02 BASE_402 FALSE Not FilteredARCH_1064 1000 1.22 1.14 3.3 200.07 BASE_402 FALSE Not FilteredARCH_1064 1000 1.22 1.14 3.6 173.69 BASE_402 FALSE Not FilteredARCH_1064 1000 1.22 1.14 3.9 152.29 BASE_402 FALSE Not FilteredARCH_1064 1000 1.22 1.14 4.2 139.64 BASE_402 FALSE Not FilteredARCH_1064 1000 1.22 1.14 4.5 125.97 BASE_402 TRUE Temperature < 130 CARCH_1064 1000 1.22 1.14 4.8 113.42 BASE_402 TRUE Temperature < 130 CARCH_1064 1000 1.22 1.14 5.1 104.74 BASE_402 TRUE Temperature < 130 CARCH_1064 1000 1.22 1.14 5.4 96.844 BASE_402 TRUE Temperature < 130 CARCH_1064 1000 1.22 1.14 5.7 88.525 BASE_402 TRUE Temperature < 130 CARCH_1064 1000 1.22 1.14 6 84.126 BASE_402 TRUE Temperature < 130 CARCH_1065 1000 1.22 1.98 2.4 1017.4 BASE_403 TRUE Temperature > 800 CARCH_1065 1000 1.22 1.98 2.7 912.53 BASE_403 TRUE Temperature > 800 CARCH_1065 1000 1.22 1.98 3 717.19 BASE_403 FALSE Not FilteredARCH_1065 1000 1.22 1.98 3.3 559.48 BASE_403 FALSE Not FilteredARCH_1065 1000 1.22 1.98 3.6 449.2 BASE_403 FALSE Not FilteredARCH_1065 1000 1.22 1.98 3.9 342.39 BASE_403 FALSE Not FilteredARCH_1065 1000 1.22 1.98 4.2 275.39 BASE_403 FALSE Not FilteredARCH_1065 1000 1.22 1.98 4.5 228.68 BASE_403 FALSE Not FilteredARCH_1065 1000 1.22 1.98 4.8 200.89 BASE_403 FALSE Not Filtered

E-5 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

ARCH_1065 1000 1.22 1.98 5.1 179.61 BASE_403 FALSE Not Filtered

ARCH_1065 1000 1.22 1.98 5.4 158.36 BASE_403 FALSE Not FilteredARCH_1065 1000 1.22 1.98 5.7 140.7 BASE_403 FALSE Not FilteredARCH_1065 1000 1.22 1.98 6 132.26 BASE_403 FALSE Not Filtered

ARCH_822 50 0.30 0.30 2.4 78.421 BASE_300 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_822 50 0.30 0.30 2.7 61.983 BASE_300 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_822 50 0.30 0.30 3 54.471 BASE_300 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_822 50 0.30 0.30 3.3 48.091 BASE_300 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_822 50 0.30 0.30 3.6 44.856 BASE_300 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_822 50 0.30 0.30 3.9 41.157 BASE_300 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_823 100 0.30 0.30 2.4 111.96 BASE_301 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_823 100 0.30 0.30 2.7 85.738 BASE_301 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_823 100 0.30 0.30 3 73.613 BASE_301 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_823 100 0.30 0.30 3.3 63.543 BASE_301 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_823 100 0.30 0.30 3.6 57.189 BASE_301 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

E-6 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

ARCH_823 100 0.30 0.30 3.9 51.926 BASE_301 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_823 100 0.30 0.30 4.2 47.036 BASE_301 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_823 100 0.30 0.30 4.5 44.597 BASE_301 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_823 100 0.30 0.30 4.8 42.113 BASE_301 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_829 50 0.30 1.14 2.4 128.48 BASE_311 TRUE Temperature < 130 CARCH_829 50 0.30 1.14 2.7 83.525 BASE_311 TRUE Temperature < 130 CARCH_829 50 0.30 1.14 3 65.94 BASE_311 TRUE Temperature < 130 CARCH_829 50 0.30 1.14 3.3 55.802 BASE_311 TRUE Temperature < 130 CARCH_829 50 0.30 1.14 3.6 50.422 BASE_311 TRUE Temperature < 130 CARCH_829 50 0.30 1.14 3.9 45.23 BASE_311 TRUE Temperature < 130 CARCH_829 50 0.30 1.14 4.2 42.194 BASE_311 TRUE Temperature < 130 CARCH_830 100 0.30 1.14 2.4 218.07 BASE_312 FALSE Not FilteredARCH_830 100 0.30 1.14 2.7 132.16 BASE_312 FALSE Not FilteredARCH_830 100 0.30 1.14 3 104.18 BASE_312 TRUE Temperature < 130 CARCH_830 100 0.30 1.14 3.3 84.312 BASE_312 TRUE Temperature < 130 CARCH_830 100 0.30 1.14 3.6 72.088 BASE_312 TRUE Temperature < 130 CARCH_830 100 0.30 1.14 3.9 64.197 BASE_312 TRUE Temperature < 130 CARCH_830 100 0.30 1.14 4.2 58.619 BASE_312 TRUE Temperature < 130 CARCH_830 100 0.30 1.14 4.5 51.953 BASE_312 TRUE Temperature < 130 C

E-7 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

ARCH_830 100 0.30 1.14 4.8 47.76 BASE_312 TRUE Temperature < 130 C

ARCH_830 100 0.30 1.14 5.1 45.075 BASE_312 TRUE Temperature < 130 CARCH_830 100 0.30 1.14 5.4 42.484 BASE_312 TRUE Temperature < 130 CARCH_836 50 0.30 1.98 2.4 266.03 BASE_322 FALSE Not FilteredARCH_836 50 0.30 1.98 2.7 146.04 BASE_322 FALSE Not FilteredARCH_836 50 0.30 1.98 3 103.12 BASE_322 TRUE Temperature < 130 CARCH_836 50 0.30 1.98 3.3 79.733 BASE_322 TRUE Temperature < 130 CARCH_836 50 0.30 1.98 3.6 68.823 BASE_322 TRUE Temperature < 130 CARCH_836 50 0.30 1.98 3.9 62.17 BASE_322 TRUE Temperature < 130 CARCH_836 50 0.30 1.98 4.2 56.616 BASE_322 TRUE Temperature < 130 CARCH_836 50 0.30 1.98 4.5 50.366 BASE_322 TRUE Temperature < 130 CARCH_836 50 0.30 1.98 4.8 46.16 BASE_322 TRUE Temperature < 130 CARCH_836 50 0.30 1.98 5.1 41.517 BASE_322 TRUE Temperature < 130 CARCH_837 100 0.30 1.98 2.4 531.44 BASE_323 FALSE Not FilteredARCH_837 100 0.30 1.98 2.7 275.75 BASE_323 FALSE Not FilteredARCH_837 100 0.30 1.98 3 191.73 BASE_323 FALSE Not FilteredARCH_837 100 0.30 1.98 3.3 138.23 BASE_323 FALSE Not FilteredARCH_837 100 0.30 1.98 3.6 111.02 BASE_323 TRUE Temperature < 130 CARCH_837 100 0.30 1.98 3.9 90.378 BASE_323 TRUE Temperature < 130 CARCH_837 100 0.30 1.98 4.2 78.574 BASE_323 TRUE Temperature < 130 CARCH_837 100 0.30 1.98 4.5 68.337 BASE_323 TRUE Temperature < 130 C

E-8 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

ARCH_837 100 0.30 1.98 4.8 62.439 BASE_323 TRUE Temperature < 130 C

ARCH_837 100 0.30 1.98 5.1 56.388 BASE_323 TRUE Temperature < 130 CARCH_837 100 0.30 1.98 5.4 50.913 BASE_323 TRUE Temperature < 130 CARCH_837 100 0.30 1.98 5.7 46.702 BASE_323 TRUE Temperature < 130 CARCH_837 100 0.30 1.98 6 43.468 BASE_323 TRUE Temperature < 130 CARCH_887 200 0.61 0.30 2.4 148.43 BASE_302 TRUE

, Source Located 1 ft. above

Ground

ARCH_887 200 0.61 0.30 2.7 100.37 BASE_302 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_887 200 0.61 0.30 3 85.081 BASE_302 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_887 200 0.61 0.30 3.3 74.859 BASE_302 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_887 200 0.61 0.30 3.6 69.47 BASE_302 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_887 200 0.61 0.30 3.9 63.212 BASE_302 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_887 200 0.61 0.30 4.2 59.739 BASE_302 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_887 200 0.61 0.30 4.5 57.879 BASE_302 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_887 200 0.61 0.30 4.8 54.59 BASE_302 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_887 200 0.61 0.30 5.1 51.417 BASE_302 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

E-9 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

ARCH_887 200 0.61 0.30 5.4 48.415 BASE_302 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_887 200 0.61 0.30 5.7 46.025 BASE_302 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_887 200 0.61 0.30 6 43.88 BASE_302 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_888 300 0.61 0.30 2.4 203.24 BASE_303 TRUE Source Located 1 ft. above GroundARCH_888 300 0.61 0.30 2.7 127.89 BASE_303 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_888 300 0.61 0.30 3 107.9 BASE_303 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_888 300 0.61 0.30 3.3 94.353 BASE_303 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_888 300 0.61 0.30 3.6 84.65 BASE_303 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_888 300 0.61 0.30 3.9 77.241 BASE_303 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_888 300 0.61 0.30 4.2 72.78 BASE_303 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_888 300 0.61 0.30 4.5 67.684 BASE_303 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_888 300 0.61 0.30 4.8 61.735 BASE_303 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_888 300 0.61 0.30 5.1 56.565 BASE_303 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_888 300 0.61 0.30 5.4 51.5 BASE_303 TRUE Temperature < 130 C , Source

E-10 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

Located 1 ft. above Ground

ARCH_888 300 0.61 0.30 5.7 48.936 BASE_303 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_888 300 0.61 0.30 6 46.643 BASE_303 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_889 400 0.61 0.30 2.4 255.22 BASE_304 TRUE Source Located 1 ft. above GroundARCH_889 400 0.61 0.30 2.7 157.96 BASE_304 TRUE Source Located 1 ft. above GroundARCH_889 400 0.61 0.30 3 127.64 BASE_304 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_889 400 0.61 0.30 3.3 109.23 BASE_304 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_889 400 0.61 0.30 3.6 98.671 BASE_304 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_889 400 0.61 0.30 3.9 88.758 BASE_304 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_889 400 0.61 0.30 4.2 80.791 BASE_304 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_889 400 0.61 0.30 4.5 73.599 BASE_304 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_889 400 0.61 0.30 4.8 69.728 BASE_304 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_889 400 0.61 0.30 5.1 66.947 BASE_304 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_889 400 0.61 0.30 5.4 62.583 BASE_304 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_889 400 0.61 0.30 5.7 57.735 BASE_304 TRUE Temperature < 130 C , Source

E-11 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

Located 1 ft. above Ground

ARCH_889 400 0.61 0.30 6 54.117 BASE_304 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_890 500 0.61 0.30 2.4 334.39 BASE_305 TRUE Source Located 1 ft. above GroundARCH_890 500 0.61 0.30 2.7 208.25 BASE_305 TRUE Source Located 1 ft. above GroundARCH_890 500 0.61 0.30 3 163.33 BASE_305 TRUE Source Located 1 ft. above GroundARCH_890 500 0.61 0.30 3.3 136.87 BASE_305 TRUE Source Located 1 ft. above GroundARCH_890 500 0.61 0.30 3.6 120.3 BASE_305 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_890 500 0.61 0.30 3.9 108.92 BASE_305 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_890 500 0.61 0.30 4.2 99.827 BASE_305 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_890 500 0.61 0.30 4.5 89.634 BASE_305 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_890 500 0.61 0.30 4.8 83.218 BASE_305 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_890 500 0.61 0.30 5.1 77.533 BASE_305 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_890 500 0.61 0.30 5.4 72.565 BASE_305 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_890 500 0.61 0.30 5.7 68.466 BASE_305 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_890 500 0.61 0.30 6 65.06 BASE_305 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

E-12 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

ARCH_891 600 0.61 0.30 2.4 392.93 BASE_306 TRUE Source Located 1 ft. above Ground

ARCH_891 600 0.61 0.30 2.7 238.68 BASE_306 TRUE Source Located 1 ft. above GroundARCH_891 600 0.61 0.30 3 182.46 BASE_306 TRUE Source Located 1 ft. above GroundARCH_891 600 0.61 0.30 3.3 151.7 BASE_306 TRUE Source Located 1 ft. above GroundARCH_891 600 0.61 0.30 3.6 132.77 BASE_306 TRUE Source Located 1 ft. above GroundARCH_891 600 0.61 0.30 3.9 117.68 BASE_306 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_891 600 0.61 0.30 4.2 105.86 BASE_306 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_891 600 0.61 0.30 4.5 97.088 BASE_306 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_891 600 0.61 0.30 4.8 89.553 BASE_306 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_891 600 0.61 0.30 5.1 83.845 BASE_306 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_891 600 0.61 0.30 5.4 77.08 BASE_306 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_891 600 0.61 0.30 5.7 70.69 BASE_306 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_891 600 0.61 0.30 6 66.18 BASE_306 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_894 200 0.61 1.14 2.4 259.92 BASE_313 FALSE Not FilteredARCH_894 200 0.61 1.14 2.7 140.83 BASE_313 FALSE Not FilteredARCH_894 200 0.61 1.14 3 107.55 BASE_313 TRUE Temperature < 130 C

E-13 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

ARCH_894 200 0.61 1.14 3.3 92.404 BASE_313 TRUE Temperature < 130 C

ARCH_894 200 0.61 1.14 3.6 80.943 BASE_313 TRUE Temperature < 130 CARCH_894 200 0.61 1.14 3.9 73.928 BASE_313 TRUE Temperature < 130 CARCH_894 200 0.61 1.14 4.2 69.147 BASE_313 TRUE Temperature < 130 CARCH_894 200 0.61 1.14 4.5 60.989 BASE_313 TRUE Temperature < 130 CARCH_894 200 0.61 1.14 4.8 56.486 BASE_313 TRUE Temperature < 130 CARCH_894 200 0.61 1.14 5.1 52.641 BASE_313 TRUE Temperature < 130 CARCH_894 200 0.61 1.14 5.4 49.817 BASE_313 TRUE Temperature < 130 CARCH_894 200 0.61 1.14 5.7 47.225 BASE_313 TRUE Temperature < 130 CARCH_894 200 0.61 1.14 6 45.813 BASE_313 TRUE Temperature < 130 CARCH_895 300 0.61 1.14 2.4 350.38 BASE_314 FALSE Not FilteredARCH_895 300 0.61 1.14 2.7 192.02 BASE_314 FALSE Not FilteredARCH_895 300 0.61 1.14 3 145.64 BASE_314 FALSE Not FilteredARCH_895 300 0.61 1.14 3.3 123.78 BASE_314 TRUE Temperature < 130 CARCH_895 300 0.61 1.14 3.6 107.6 BASE_314 TRUE Temperature < 130 CARCH_895 300 0.61 1.14 3.9 96.495 BASE_314 TRUE Temperature < 130 CARCH_895 300 0.61 1.14 4.2 89.162 BASE_314 TRUE Temperature < 130 CARCH_895 300 0.61 1.14 4.5 82.797 BASE_314 TRUE Temperature < 130 CARCH_895 300 0.61 1.14 4.8 76.094 BASE_314 TRUE Temperature < 130 CARCH_895 300 0.61 1.14 5.1 70.124 BASE_314 TRUE Temperature < 130 CARCH_895 300 0.61 1.14 5.4 65.595 BASE_314 TRUE Temperature < 130 C

E-14 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

ARCH_895 300 0.61 1.14 5.7 60.586 BASE_314 TRUE Temperature < 130 C

ARCH_895 300 0.61 1.14 6 57.174 BASE_314 TRUE Temperature < 130 CARCH_896 400 0.61 1.14 2.4 575.97 BASE_315 FALSE Not FilteredARCH_896 400 0.61 1.14 2.7 273.67 BASE_315 FALSE Not FilteredARCH_896 400 0.61 1.14 3 192.71 BASE_315 FALSE Not FilteredARCH_896 400 0.61 1.14 3.3 155.45 BASE_315 FALSE Not FilteredARCH_896 400 0.61 1.14 3.6 135.42 BASE_315 FALSE Not FilteredARCH_896 400 0.61 1.14 3.9 119.35 BASE_315 TRUE Temperature < 130 CARCH_896 400 0.61 1.14 4.2 105.99 BASE_315 TRUE Temperature < 130 CARCH_896 400 0.61 1.14 4.5 95.01 BASE_315 TRUE Temperature < 130 CARCH_896 400 0.61 1.14 4.8 86.706 BASE_315 TRUE Temperature < 130 CARCH_896 400 0.61 1.14 5.1 79.523 BASE_315 TRUE Temperature < 130 CARCH_896 400 0.61 1.14 5.4 73.124 BASE_315 TRUE Temperature < 130 CARCH_896 400 0.61 1.14 5.7 68.01 BASE_315 TRUE Temperature < 130 CARCH_896 400 0.61 1.14 6 64.528 BASE_315 TRUE Temperature < 130 CARCH_897 500 0.61 1.14 2.4 705.87 BASE_316 FALSE Not FilteredARCH_897 500 0.61 1.14 2.7 405.73 BASE_316 FALSE Not FilteredARCH_897 500 0.61 1.14 3 275.53 BASE_316 FALSE Not FilteredARCH_897 500 0.61 1.14 3.3 207.46 BASE_316 FALSE Not FilteredARCH_897 500 0.61 1.14 3.6 175.04 BASE_316 FALSE Not FilteredARCH_897 500 0.61 1.14 3.9 151.32 BASE_316 FALSE Not Filtered

E-15 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

ARCH_897 500 0.61 1.14 4.2 134.1 BASE_316 FALSE Not Filtered

ARCH_897 500 0.61 1.14 4.5 116.32 BASE_316 TRUE Temperature < 130 CARCH_897 500 0.61 1.14 4.8 105.38 BASE_316 TRUE Temperature < 130 CARCH_897 500 0.61 1.14 5.1 98.169 BASE_316 TRUE Temperature < 130 CARCH_897 500 0.61 1.14 5.4 90.329 BASE_316 TRUE Temperature < 130 CARCH_897 500 0.61 1.14 5.7 83.386 BASE_316 TRUE Temperature < 130 CARCH_897 500 0.61 1.14 6 77.358 BASE_316 TRUE Temperature < 130 CARCH_898 600 0.61 1.14 2.4 777.31 BASE_317 FALSE Not FilteredARCH_898 600 0.61 1.14 2.7 455.11 BASE_317 FALSE Not FilteredARCH_898 600 0.61 1.14 3 337.58 BASE_317 FALSE Not FilteredARCH_898 600 0.61 1.14 3.3 252 BASE_317 FALSE Not FilteredARCH_898 600 0.61 1.14 3.6 213.7 BASE_317 FALSE Not FilteredARCH_898 600 0.61 1.14 3.9 178.56 BASE_317 FALSE Not FilteredARCH_898 600 0.61 1.14 4.2 154.6 BASE_317 FALSE Not FilteredARCH_898 600 0.61 1.14 4.5 133.8 BASE_317 FALSE Not FilteredARCH_898 600 0.61 1.14 4.8 121.31 BASE_317 TRUE Temperature < 130 CARCH_898 600 0.61 1.14 5.1 107.65 BASE_317 TRUE Temperature < 130 CARCH_898 600 0.61 1.14 5.4 97.561 BASE_317 TRUE Temperature < 130 CARCH_898 600 0.61 1.14 5.7 89.094 BASE_317 TRUE Temperature < 130 CARCH_898 600 0.61 1.14 6 82.72 BASE_317 TRUE Temperature < 130 CARCH_901 200 0.61 1.98 2.4 693.58 BASE_324 FALSE Not Filtered

E-16 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

ARCH_901 200 0.61 1.98 2.7 369.88 BASE_324 FALSE Not Filtered

ARCH_901 200 0.61 1.98 3 253.64 BASE_324 FALSE Not FilteredARCH_901 200 0.61 1.98 3.3 194.13 BASE_324 FALSE Not FilteredARCH_901 200 0.61 1.98 3.6 161.03 BASE_324 FALSE Not FilteredARCH_901 200 0.61 1.98 3.9 130.93 BASE_324 FALSE Not FilteredARCH_901 200 0.61 1.98 4.2 111.32 BASE_324 TRUE Temperature < 130 CARCH_901 200 0.61 1.98 4.5 97.46 BASE_324 TRUE Temperature < 130 CARCH_901 200 0.61 1.98 4.8 89.489 BASE_324 TRUE Temperature < 130 CARCH_901 200 0.61 1.98 5.1 82.647 BASE_324 TRUE Temperature < 130 CARCH_901 200 0.61 1.98 5.4 72.712 BASE_324 TRUE Temperature < 130 CARCH_901 200 0.61 1.98 5.7 65.348 BASE_324 TRUE Temperature < 130 CARCH_901 200 0.61 1.98 6 59.505 BASE_324 TRUE Temperature < 130 CARCH_902 300 0.61 1.98 2.4 931.25 BASE_325 TRUE Temperature > 800 CARCH_902 300 0.61 1.98 2.7 657.24 BASE_325 FALSE Not FilteredARCH_902 300 0.61 1.98 3 450.61 BASE_325 FALSE Not FilteredARCH_902 300 0.61 1.98 3.3 345.15 BASE_325 FALSE Not FilteredARCH_902 300 0.61 1.98 3.6 272.2 BASE_325 FALSE Not FilteredARCH_902 300 0.61 1.98 3.9 214.8 BASE_325 FALSE Not FilteredARCH_902 300 0.61 1.98 4.2 178.08 BASE_325 FALSE Not FilteredARCH_902 300 0.61 1.98 4.5 146.34 BASE_325 FALSE Not FilteredARCH_902 300 0.61 1.98 4.8 129.83 BASE_325 TRUE Temperature < 130 C

E-17 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

ARCH_902 300 0.61 1.98 5.1 118.19 BASE_325 TRUE Temperature < 130 C

ARCH_902 300 0.61 1.98 5.4 101.98 BASE_325 TRUE Temperature < 130 CARCH_902 300 0.61 1.98 5.7 92.618 BASE_325 TRUE Temperature < 130 CARCH_902 300 0.61 1.98 6 86.111 BASE_325 TRUE Temperature < 130 CARCH_903 400 0.61 1.98 2.4 1006.2 BASE_326 TRUE Temperature > 800 CARCH_903 400 0.61 1.98 2.7 884.94 BASE_326 TRUE Temperature > 800 CARCH_903 400 0.61 1.98 3 712.12 BASE_326 FALSE Not FilteredARCH_903 400 0.61 1.98 3.3 515.23 BASE_326 FALSE Not FilteredARCH_903 400 0.61 1.98 3.6 387.41 BASE_326 FALSE Not FilteredARCH_903 400 0.61 1.98 3.9 289.44 BASE_326 FALSE Not FilteredARCH_903 400 0.61 1.98 4.2 232.59 BASE_326 FALSE Not FilteredARCH_903 400 0.61 1.98 4.5 183.52 BASE_326 FALSE Not FilteredARCH_903 400 0.61 1.98 4.8 157.37 BASE_326 FALSE Not FilteredARCH_903 400 0.61 1.98 5.1 138.3 BASE_326 FALSE Not FilteredARCH_903 400 0.61 1.98 5.4 121.29 BASE_326 TRUE Temperature < 130 CARCH_903 400 0.61 1.98 5.7 108.2 BASE_326 TRUE Temperature < 130 CARCH_903 400 0.61 1.98 6 99.461 BASE_326 TRUE Temperature < 130 CARCH_904 500 0.61 1.98 2.4 1057.3 BASE_327 TRUE Temperature > 800 CARCH_904 500 0.61 1.98 2.7 1014.7 BASE_327 TRUE Temperature > 800 CARCH_904 500 0.61 1.98 3 921.04 BASE_327 TRUE Temperature > 800 CARCH_904 500 0.61 1.98 3.3 753.53 BASE_327 FALSE Not Filtered

E-18 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

ARCH_904 500 0.61 1.98 3.6 594.4 BASE_327 FALSE Not Filtered

ARCH_904 500 0.61 1.98 3.9 434.66 BASE_327 FALSE Not FilteredARCH_904 500 0.61 1.98 4.2 334.39 BASE_327 FALSE Not FilteredARCH_904 500 0.61 1.98 4.5 256.69 BASE_327 FALSE Not FilteredARCH_904 500 0.61 1.98 4.8 213.59 BASE_327 FALSE Not FilteredARCH_904 500 0.61 1.98 5.1 182.15 BASE_327 FALSE Not FilteredARCH_904 500 0.61 1.98 5.4 158.1 BASE_327 FALSE Not FilteredARCH_904 500 0.61 1.98 5.7 135.49 BASE_327 FALSE Not FilteredARCH_904 500 0.61 1.98 6 119.78 BASE_327 TRUE Temperature < 130 CARCH_905 600 0.61 1.98 2.4 1103.1 BASE_328 TRUE Temperature > 800 CARCH_905 600 0.61 1.98 2.7 1061.1 BASE_328 TRUE Temperature > 800 CARCH_905 600 0.61 1.98 3 1012.7 BASE_328 TRUE Temperature > 800 CARCH_905 600 0.61 1.98 3.3 890.92 BASE_328 TRUE Temperature > 800 CARCH_905 600 0.61 1.98 3.6 734.06 BASE_328 FALSE Not FilteredARCH_905 600 0.61 1.98 3.9 533.68 BASE_328 FALSE Not FilteredARCH_905 600 0.61 1.98 4.2 418.77 BASE_328 FALSE Not FilteredARCH_905 600 0.61 1.98 4.5 319.55 BASE_328 FALSE Not FilteredARCH_905 600 0.61 1.98 4.8 263.95 BASE_328 FALSE Not FilteredARCH_905 600 0.61 1.98 5.1 218.04 BASE_328 FALSE Not FilteredARCH_905 600 0.61 1.98 5.4 182.57 BASE_328 FALSE Not FilteredARCH_905 600 0.61 1.98 5.7 154.08 BASE_328 FALSE Not Filtered

E-19 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

ARCH_905 600 0.61 1.98 6 136.82 BASE_328 FALSE Not Filtered

ARCH_951 300 0.91 0.30 2.4 142.3 BASE_307 TRUE Source Located 1 ft. above GroundARCH_951 300 0.91 0.30 2.7 100.22 BASE_307 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_951 300 0.91 0.30 3 85.336 BASE_307 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_951 300 0.91 0.30 3.3 75.533 BASE_307 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_951 300 0.91 0.30 3.6 71.239 BASE_307 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_951 300 0.91 0.30 3.9 65.25 BASE_307 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_951 300 0.91 0.30 4.2 61.878 BASE_307 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_951 300 0.91 0.30 4.5 57.541 BASE_307 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_951 300 0.91 0.30 4.8 54.979 BASE_307 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_951 300 0.91 0.30 5.1 52.798 BASE_307 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_951 300 0.91 0.30 5.4 51.555 BASE_307 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_951 300 0.91 0.30 5.7 49.802 BASE_307 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_951 300 0.91 0.30 6 47.649 BASE_307 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

E-20 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

ARCH_952 400 0.91 0.30 2.4 181.52 BASE_308 TRUE Source Located 1 ft. above Ground

ARCH_952 400 0.91 0.30 2.7 119.53 BASE_308 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_952 400 0.91 0.30 3 101.81 BASE_308 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_952 400 0.91 0.30 3.3 90.742 BASE_308 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_952 400 0.91 0.30 3.6 82.895 BASE_308 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_952 400 0.91 0.30 3.9 76.825 BASE_308 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_952 400 0.91 0.30 4.2 71.033 BASE_308 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_952 400 0.91 0.30 4.5 66.905 BASE_308 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_952 400 0.91 0.30 4.8 63.285 BASE_308 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_952 400 0.91 0.30 5.1 60.726 BASE_308 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_952 400 0.91 0.30 5.4 58.829 BASE_308 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_952 400 0.91 0.30 5.7 56.644 BASE_308 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_952 400 0.91 0.30 6 54.836 BASE_308 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_953 500 0.91 0.30 2.4 222.62 BASE_309 TRUE Source Located 1 ft. above Ground

E-21 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

ARCH_953 500 0.91 0.30 2.7 144.54 BASE_309 TRUE Source Located 1 ft. above Ground

ARCH_953 500 0.91 0.30 3 119.47 BASE_309 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_953 500 0.91 0.30 3.3 104.67 BASE_309 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_953 500 0.91 0.30 3.6 97.276 BASE_309 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_953 500 0.91 0.30 3.9 88.925 BASE_309 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_953 500 0.91 0.30 4.2 81.512 BASE_309 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_953 500 0.91 0.30 4.5 76.345 BASE_309 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_953 500 0.91 0.30 4.8 72.617 BASE_309 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_953 500 0.91 0.30 5.1 70.106 BASE_309 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_953 500 0.91 0.30 5.4 67.562 BASE_309 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_953 500 0.91 0.30 5.7 65.966 BASE_309 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_953 500 0.91 0.30 6 63.074 BASE_309 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_954 600 0.91 0.30 2.4 249.34 BASE_310 TRUE Source Located 1 ft. above GroundARCH_954 600 0.91 0.30 2.7 160.57 BASE_310 TRUE Source Located 1 ft. above GroundARCH_954 600 0.91 0.30 3 131.61 BASE_310 TRUE Source Located 1 ft. above Ground

E-22 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

ARCH_954 600 0.91 0.30 3.3 115.48 BASE_310 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_954 600 0.91 0.30 3.6 105.73 BASE_310 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_954 600 0.91 0.30 3.9 96.502 BASE_310 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_954 600 0.91 0.30 4.2 88.467 BASE_310 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_954 600 0.91 0.30 4.5 81.004 BASE_310 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_954 600 0.91 0.30 4.8 75.232 BASE_310 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_954 600 0.91 0.30 5.1 71.754 BASE_310 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_954 600 0.91 0.30 5.4 68.018 BASE_310 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_954 600 0.91 0.30 5.7 65.049 BASE_310 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_954 600 0.91 0.30 6 63.057 BASE_310 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

ARCH_958 300 0.91 1.14 2.4 221.52 BASE_318 FALSE Not FilteredARCH_958 300 0.91 1.14 2.7 135.52 BASE_318 FALSE Not FilteredARCH_958 300 0.91 1.14 3 109.65 BASE_318 TRUE Temperature < 130 CARCH_958 300 0.91 1.14 3.3 94 BASE_318 TRUE Temperature < 130 CARCH_958 300 0.91 1.14 3.6 82.876 BASE_318 TRUE Temperature < 130 C

E-23 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

ARCH_958 300 0.91 1.14 3.9 74.375 BASE_318 TRUE Temperature < 130 C

ARCH_958 300 0.91 1.14 4.2 69.917 BASE_318 TRUE Temperature < 130 CARCH_958 300 0.91 1.14 4.5 64.995 BASE_318 TRUE Temperature < 130 CARCH_958 300 0.91 1.14 4.8 60.525 BASE_318 TRUE Temperature < 130 CARCH_958 300 0.91 1.14 5.1 57.31 BASE_318 TRUE Temperature < 130 CARCH_958 300 0.91 1.14 5.4 54.302 BASE_318 TRUE Temperature < 130 CARCH_958 300 0.91 1.14 5.7 51.35 BASE_318 TRUE Temperature < 130 CARCH_958 300 0.91 1.14 6 49.543 BASE_318 TRUE Temperature < 130 CARCH_959 400 0.91 1.14 2.4 274.49 BASE_319 FALSE Not FilteredARCH_959 400 0.91 1.14 2.7 170.19 BASE_319 FALSE Not FilteredARCH_959 400 0.91 1.14 3 135.72 BASE_319 FALSE Not FilteredARCH_959 400 0.91 1.14 3.3 111.31 BASE_319 TRUE Temperature < 130 CARCH_959 400 0.91 1.14 3.6 97.466 BASE_319 TRUE Temperature < 130 CARCH_959 400 0.91 1.14 3.9 88.814 BASE_319 TRUE Temperature < 130 CARCH_959 400 0.91 1.14 4.2 83.577 BASE_319 TRUE Temperature < 130 CARCH_959 400 0.91 1.14 4.5 77.256 BASE_319 TRUE Temperature < 130 CARCH_959 400 0.91 1.14 4.8 72.615 BASE_319 TRUE Temperature < 130 CARCH_959 400 0.91 1.14 5.1 66.86 BASE_319 TRUE Temperature < 130 CARCH_959 400 0.91 1.14 5.4 61.074 BASE_319 TRUE Temperature < 130 CARCH_959 400 0.91 1.14 5.7 56.642 BASE_319 TRUE Temperature < 130 CARCH_959 400 0.91 1.14 6 53.967 BASE_319 TRUE Temperature < 130 C

E-24 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

ARCH_960 500 0.91 1.14 2.4 371.76 BASE_320 FALSE Not Filtered

ARCH_960 500 0.91 1.14 2.7 206.86 BASE_320 FALSE Not FilteredARCH_960 500 0.91 1.14 3 166.01 BASE_320 FALSE Not FilteredARCH_960 500 0.91 1.14 3.3 137.15 BASE_320 FALSE Not FilteredARCH_960 500 0.91 1.14 3.6 120.9 BASE_320 TRUE Temperature < 130 CARCH_960 500 0.91 1.14 3.9 110.17 BASE_320 TRUE Temperature < 130 CARCH_960 500 0.91 1.14 4.2 100.36 BASE_320 TRUE Temperature < 130 CARCH_960 500 0.91 1.14 4.5 91.016 BASE_320 TRUE Temperature < 130 CARCH_960 500 0.91 1.14 4.8 84.619 BASE_320 TRUE Temperature < 130 CARCH_960 500 0.91 1.14 5.1 79.613 BASE_320 TRUE Temperature < 130 CARCH_960 500 0.91 1.14 5.4 72.486 BASE_320 TRUE Temperature < 130 CARCH_960 500 0.91 1.14 5.7 65.353 BASE_320 TRUE Temperature < 130 CARCH_960 500 0.91 1.14 6 61.863 BASE_320 TRUE Temperature < 130 CARCH_961 600 0.91 1.14 2.4 432.98 BASE_321 FALSE Not FilteredARCH_961 600 0.91 1.14 2.7 237.42 BASE_321 FALSE Not FilteredARCH_961 600 0.91 1.14 3 184.16 BASE_321 FALSE Not FilteredARCH_961 600 0.91 1.14 3.3 152.43 BASE_321 FALSE Not FilteredARCH_961 600 0.91 1.14 3.6 133.03 BASE_321 FALSE Not FilteredARCH_961 600 0.91 1.14 3.9 119.15 BASE_321 TRUE Temperature < 130 CARCH_961 600 0.91 1.14 4.2 109.24 BASE_321 TRUE Temperature < 130 CARCH_961 600 0.91 1.14 4.5 100.67 BASE_321 TRUE Temperature < 130 C

E-25 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

ARCH_961 600 0.91 1.14 4.8 92.7 BASE_321 TRUE Temperature < 130 C

ARCH_961 600 0.91 1.14 5.1 86.482 BASE_321 TRUE Temperature < 130 CARCH_961 600 0.91 1.14 5.4 80.763 BASE_321 TRUE Temperature < 130 CARCH_961 600 0.91 1.14 5.7 73.875 BASE_321 TRUE Temperature < 130 CARCH_961 600 0.91 1.14 6 68.907 BASE_321 TRUE Temperature < 130 CARCH_965 300 0.91 1.98 2.4 607.47 BASE_329 FALSE Not FilteredARCH_965 300 0.91 1.98 2.7 331.53 BASE_329 FALSE Not FilteredARCH_965 300 0.91 1.98 3 232.09 BASE_329 FALSE Not FilteredARCH_965 300 0.91 1.98 3.3 177.64 BASE_329 FALSE Not FilteredARCH_965 300 0.91 1.98 3.6 146.25 BASE_329 FALSE Not FilteredARCH_965 300 0.91 1.98 3.9 126.7 BASE_329 TRUE Temperature < 130 CARCH_965 300 0.91 1.98 4.2 112.7 BASE_329 TRUE Temperature < 130 CARCH_965 300 0.91 1.98 4.5 98.797 BASE_329 TRUE Temperature < 130 CARCH_965 300 0.91 1.98 4.8 90.066 BASE_329 TRUE Temperature < 130 CARCH_965 300 0.91 1.98 5.1 83.373 BASE_329 TRUE Temperature < 130 CARCH_965 300 0.91 1.98 5.4 78.82 BASE_329 TRUE Temperature < 130 CARCH_965 300 0.91 1.98 5.7 73.241 BASE_329 TRUE Temperature < 130 CARCH_965 300 0.91 1.98 6 68.812 BASE_329 TRUE Temperature < 130 CARCH_966 400 0.91 1.98 2.4 868.44 BASE_330 TRUE Temperature > 800 CARCH_966 400 0.91 1.98 2.7 552.14 BASE_330 FALSE Not FilteredARCH_966 400 0.91 1.98 3 368 BASE_330 FALSE Not Filtered

E-26 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

ARCH_966 400 0.91 1.98 3.3 275.26 BASE_330 FALSE Not Filtered

ARCH_966 400 0.91 1.98 3.6 219.12 BASE_330 FALSE Not FilteredARCH_966 400 0.91 1.98 3.9 180.14 BASE_330 FALSE Not FilteredARCH_966 400 0.91 1.98 4.2 154.08 BASE_330 FALSE Not FilteredARCH_966 400 0.91 1.98 4.5 130.46 BASE_330 FALSE Not FilteredARCH_966 400 0.91 1.98 4.8 114.68 BASE_330 TRUE Temperature < 130 CARCH_966 400 0.91 1.98 5.1 102.07 BASE_330 TRUE Temperature < 130 CARCH_966 400 0.91 1.98 5.4 92.363 BASE_330 TRUE Temperature < 130 CARCH_966 400 0.91 1.98 5.7 85.204 BASE_330 TRUE Temperature < 130 CARCH_966 400 0.91 1.98 6 80.246 BASE_330 TRUE Temperature < 130 CARCH_967 500 0.91 1.98 2.4 887.06 BASE_331 TRUE Temperature > 800 CARCH_967 500 0.91 1.98 2.7 642.57 BASE_331 FALSE Not FilteredARCH_967 500 0.91 1.98 3 449.19 BASE_331 FALSE Not FilteredARCH_967 500 0.91 1.98 3.3 324.39 BASE_331 FALSE Not FilteredARCH_967 500 0.91 1.98 3.6 252.72 BASE_331 FALSE Not FilteredARCH_967 500 0.91 1.98 3.9 216.54 BASE_331 FALSE Not FilteredARCH_967 500 0.91 1.98 4.2 183.63 BASE_331 FALSE Not FilteredARCH_967 500 0.91 1.98 4.5 153.81 BASE_331 FALSE Not FilteredARCH_967 500 0.91 1.98 4.8 134.52 BASE_331 FALSE Not FilteredARCH_967 500 0.91 1.98 5.1 119.4 BASE_331 TRUE Temperature < 130 CARCH_967 500 0.91 1.98 5.4 107.44 BASE_331 TRUE Temperature < 130 C

E-27 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

ARCH_967 500 0.91 1.98 5.7 98.525 BASE_331 TRUE Temperature < 130 C

ARCH_967 500 0.91 1.98 6 91.036 BASE_331 TRUE Temperature < 130 CARCH_968 600 0.91 1.98 2.4 965.8 BASE_332 TRUE Temperature > 800 CARCH_968 600 0.91 1.98 2.7 717.36 BASE_332 FALSE Not FilteredARCH_968 600 0.91 1.98 3 549.99 BASE_332 FALSE Not FilteredARCH_968 600 0.91 1.98 3.3 412.15 BASE_332 FALSE Not FilteredARCH_968 600 0.91 1.98 3.6 311.81 BASE_332 FALSE Not FilteredARCH_968 600 0.91 1.98 3.9 245.14 BASE_332 FALSE Not FilteredARCH_968 600 0.91 1.98 4.2 209.01 BASE_332 FALSE Not FilteredARCH_968 600 0.91 1.98 4.5 173.48 BASE_332 FALSE Not FilteredARCH_968 600 0.91 1.98 4.8 149.83 BASE_332 FALSE Not FilteredARCH_968 600 0.91 1.98 5.1 131.62 BASE_332 FALSE Not FilteredARCH_968 600 0.91 1.98 5.4 118.34 BASE_332 TRUE Temperature < 130 CARCH_968 600 0.91 1.98 5.7 106.75 BASE_332 TRUE Temperature < 130 CARCH_968 600 0.91 1.98 6 99.896 BASE_332 TRUE Temperature < 130 C

OBST_1051 1000 0.91 0.30 2.4 533.89 BASE_404 TRUE Source Located 1 ft. above GroundOBST_1051 1000 0.91 0.30 2.7 422.39 BASE_404 TRUE Source Located 1 ft. above GroundOBST_1051 1000 0.91 0.30 3 340.68 BASE_404 TRUE Source Located 1 ft. above GroundOBST_1051 1000 0.91 0.30 3.3 270.01 BASE_404 TRUE Source Located 1 ft. above GroundOBST_1051 1000 0.91 0.30 3.6 233.57 BASE_404 TRUE Source Located 1 ft. above GroundOBST_1051 1000 0.91 0.30 3.9 215.99 BASE_404 TRUE Source Located 1 ft. above Ground

E-28 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

OBST_1051 1000 0.91 0.30 4.2 206.03 BASE_404 TRUE Source Located 1 ft. above Ground

OBST_1051 1000 0.91 0.30 4.5 193.24 BASE_404 TRUE Source Located 1 ft. above GroundOBST_1051 1000 0.91 0.30 4.8 182.06 BASE_404 TRUE Source Located 1 ft. above GroundOBST_1051 1000 0.91 0.30 5.1 172.23 BASE_404 TRUE Source Located 1 ft. above GroundOBST_1051 1000 0.91 0.30 5.4 163.41 BASE_404 TRUE Source Located 1 ft. above GroundOBST_1051 1000 0.91 0.30 5.7 155.42 BASE_404 TRUE Source Located 1 ft. above GroundOBST_1051 1000 0.91 0.30 6 147.94 BASE_404 TRUE Source Located 1 ft. above GroundOBST_1052 1000 0.91 1.14 2.4 828.59 BASE_400 TRUE Temperature > 800 COBST_1052 1000 0.91 1.14 2.7 639.49 BASE_400 FALSE Not FilteredOBST_1052 1000 0.91 1.14 3 485.41 BASE_400 FALSE Not FilteredOBST_1052 1000 0.91 1.14 3.3 380.12 BASE_400 FALSE Not FilteredOBST_1052 1000 0.91 1.14 3.6 338.6 BASE_400 FALSE Not FilteredOBST_1052 1000 0.91 1.14 3.9 319.22 BASE_400 FALSE Not FilteredOBST_1052 1000 0.91 1.14 4.2 306.21 BASE_400 FALSE Not FilteredOBST_1052 1000 0.91 1.14 4.5 288.02 BASE_400 FALSE Not FilteredOBST_1052 1000 0.91 1.14 4.8 270.8 BASE_400 FALSE Not FilteredOBST_1052 1000 0.91 1.14 5.1 255.33 BASE_400 FALSE Not FilteredOBST_1052 1000 0.91 1.14 5.4 236.32 BASE_400 FALSE Not FilteredOBST_1052 1000 0.91 1.14 5.7 219.16 BASE_400 FALSE Not FilteredOBST_1052 1000 0.91 1.14 6 204.84 BASE_400 FALSE Not FilteredOBST_1053 1000 0.91 1.98 2.4 1086.9 BASE_401 TRUE Temperature > 800 C

E-29 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

OBST_1053 1000 0.91 1.98 2.7 883.59 BASE_401 TRUE Temperature > 800 C

OBST_1053 1000 0.91 1.98 3 823.73 BASE_401 TRUE Temperature > 800 COBST_1053 1000 0.91 1.98 3.3 734.4 BASE_401 FALSE Not FilteredOBST_1053 1000 0.91 1.98 3.6 670.23 BASE_401 FALSE Not FilteredOBST_1053 1000 0.91 1.98 3.9 596.13 BASE_401 FALSE Not FilteredOBST_1053 1000 0.91 1.98 4.2 534.31 BASE_401 FALSE Not FilteredOBST_1053 1000 0.91 1.98 4.5 470.83 BASE_401 FALSE Not FilteredOBST_1053 1000 0.91 1.98 4.8 424.86 BASE_401 FALSE Not FilteredOBST_1053 1000 0.91 1.98 5.1 382.82 BASE_401 FALSE Not FilteredOBST_1053 1000 0.91 1.98 5.4 333 BASE_401 FALSE Not FilteredOBST_1053 1000 0.91 1.98 5.7 293.13 BASE_401 FALSE Not FilteredOBST_1053 1000 0.91 1.98 6 258.54 BASE_401 FALSE Not FilteredOBST_1060 1000 1.22 0.30 2.4 397.06 BASE_405 TRUE Source Located 1 ft. above GroundOBST_1060 1000 1.22 0.30 2.7 319.73 BASE_405 TRUE Source Located 1 ft. above GroundOBST_1060 1000 1.22 0.30 3 250.83 BASE_405 TRUE Source Located 1 ft. above GroundOBST_1060 1000 1.22 0.30 3.3 197.52 BASE_405 TRUE Source Located 1 ft. above GroundOBST_1060 1000 1.22 0.30 3.6 182.14 BASE_405 TRUE Source Located 1 ft. above GroundOBST_1060 1000 1.22 0.30 3.9 171.16 BASE_405 TRUE Source Located 1 ft. above GroundOBST_1060 1000 1.22 0.30 4.2 163.99 BASE_405 TRUE Source Located 1 ft. above GroundOBST_1060 1000 1.22 0.30 4.5 157.72 BASE_405 TRUE Source Located 1 ft. above GroundOBST_1060 1000 1.22 0.30 4.8 152.54 BASE_405 TRUE Source Located 1 ft. above Ground

E-30 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

OBST_1060 1000 1.22 0.30 5.1 147.72 BASE_405 TRUE Source Located 1 ft. above Ground

OBST_1060 1000 1.22 0.30 5.4 141.96 BASE_405 TRUE Source Located 1 ft. above GroundOBST_1060 1000 1.22 0.30 5.7 135.56 BASE_405 TRUE Source Located 1 ft. above GroundOBST_1060 1000 1.22 0.30 6 131.27 BASE_405 TRUE Source Located 1 ft. above GroundOBST_1061 1000 1.22 1.14 2.4 688.56 BASE_402 FALSE Not FilteredOBST_1061 1000 1.22 1.14 2.7 513.44 BASE_402 FALSE Not FilteredOBST_1061 1000 1.22 1.14 3 396.9 BASE_402 FALSE Not FilteredOBST_1061 1000 1.22 1.14 3.3 320.69 BASE_402 FALSE Not FilteredOBST_1061 1000 1.22 1.14 3.6 279.7 BASE_402 FALSE Not FilteredOBST_1061 1000 1.22 1.14 3.9 255.99 BASE_402 FALSE Not FilteredOBST_1061 1000 1.22 1.14 4.2 239.89 BASE_402 FALSE Not FilteredOBST_1061 1000 1.22 1.14 4.5 226.26 BASE_402 FALSE Not FilteredOBST_1061 1000 1.22 1.14 4.8 216.94 BASE_402 FALSE Not FilteredOBST_1061 1000 1.22 1.14 5.1 207.38 BASE_402 FALSE Not FilteredOBST_1061 1000 1.22 1.14 5.4 196.74 BASE_402 FALSE Not FilteredOBST_1061 1000 1.22 1.14 5.7 184 BASE_402 FALSE Not FilteredOBST_1061 1000 1.22 1.14 6 172.26 BASE_402 FALSE Not FilteredOBST_1062 1000 1.22 1.98 2.4 1024.3 BASE_403 TRUE Temperature > 800 COBST_1062 1000 1.22 1.98 2.7 743.77 BASE_403 FALSE Not FilteredOBST_1062 1000 1.22 1.98 3 668.11 BASE_403 FALSE Not FilteredOBST_1062 1000 1.22 1.98 3.3 599.14 BASE_403 FALSE Not Filtered

E-31 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

OBST_1062 1000 1.22 1.98 3.6 551 BASE_403 FALSE Not Filtered

OBST_1062 1000 1.22 1.98 3.9 494.5 BASE_403 FALSE Not FilteredOBST_1062 1000 1.22 1.98 4.2 446.72 BASE_403 FALSE Not FilteredOBST_1062 1000 1.22 1.98 4.5 405.71 BASE_403 FALSE Not FilteredOBST_1062 1000 1.22 1.98 4.8 367.67 BASE_403 FALSE Not FilteredOBST_1062 1000 1.22 1.98 5.1 333.88 BASE_403 FALSE Not FilteredOBST_1062 1000 1.22 1.98 5.4 295.56 BASE_403 FALSE Not FilteredOBST_1062 1000 1.22 1.98 5.7 259.91 BASE_403 FALSE Not FilteredOBST_1062 1000 1.22 1.98 6 233 BASE_403 FALSE Not Filtered

OBST_801 50 0.30 0.30 2.4 87.091 BASE_300 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_801 50 0.30 0.30 2.7 74.382 BASE_300 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_801 50 0.30 0.30 3 67.295 BASE_300 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_801 50 0.30 0.30 3.3 60.832 BASE_300 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_801 50 0.30 0.30 3.6 56.846 BASE_300 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_801 50 0.30 0.30 3.9 53.889 BASE_300 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_801 50 0.30 0.30 4.2 51.386 BASE_300 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_801 50 0.30 0.30 4.5 48.698 BASE_300 TRUE Temperature < 130 C , Source

E-32 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

Located 1 ft. above Ground

OBST_801 50 0.30 0.30 4.8 45.556 BASE_300 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_801 50 0.30 0.30 5.1 43.585 BASE_300 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_801 50 0.30 0.30 5.4 40.939 BASE_300 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_802 100 0.30 0.30 2.4 150.06 BASE_301 TRUE Source Located 1 ft. above GroundOBST_802 100 0.30 0.30 2.7 115.07 BASE_301 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_802 100 0.30 0.30 3 106.42 BASE_301 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_802 100 0.30 0.30 3.3 97.657 BASE_301 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_802 100 0.30 0.30 3.6 88.334 BASE_301 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_802 100 0.30 0.30 3.9 81.554 BASE_301 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_802 100 0.30 0.30 4.2 74.802 BASE_301 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_802 100 0.30 0.30 4.5 67.73 BASE_301 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_802 100 0.30 0.30 4.8 64.039 BASE_301 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_802 100 0.30 0.30 5.1 60.336 BASE_301 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

E-33 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

OBST_802 100 0.30 0.30 5.4 56.214 BASE_301 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_802 100 0.30 0.30 5.7 52.062 BASE_301 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_802 100 0.30 0.30 6 49.453 BASE_301 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_808 50 0.30 1.14 2.4 138.47 BASE_311 FALSE Not FilteredOBST_808 50 0.30 1.14 2.7 100.55 BASE_311 TRUE Temperature < 130 COBST_808 50 0.30 1.14 3 82.454 BASE_311 TRUE Temperature < 130 COBST_808 50 0.30 1.14 3.3 75.188 BASE_311 TRUE Temperature < 130 COBST_808 50 0.30 1.14 3.6 70.849 BASE_311 TRUE Temperature < 130 COBST_808 50 0.30 1.14 3.9 66.382 BASE_311 TRUE Temperature < 130 COBST_808 50 0.30 1.14 4.2 62.626 BASE_311 TRUE Temperature < 130 COBST_808 50 0.30 1.14 4.5 58.6 BASE_311 TRUE Temperature < 130 COBST_808 50 0.30 1.14 4.8 54.769 BASE_311 TRUE Temperature < 130 COBST_808 50 0.30 1.14 5.1 51.378 BASE_311 TRUE Temperature < 130 COBST_808 50 0.30 1.14 5.4 48.644 BASE_311 TRUE Temperature < 130 COBST_808 50 0.30 1.14 5.7 45.892 BASE_311 TRUE Temperature < 130 COBST_808 50 0.30 1.14 6 44.185 BASE_311 TRUE Temperature < 130 COBST_809 100 0.30 1.14 2.4 235.87 BASE_312 FALSE Not FilteredOBST_809 100 0.30 1.14 2.7 155.85 BASE_312 FALSE Not FilteredOBST_809 100 0.30 1.14 3 121.47 BASE_312 TRUE Temperature < 130 C

E-34 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

OBST_809 100 0.30 1.14 3.3 110.1 BASE_312 TRUE Temperature < 130 C

OBST_809 100 0.30 1.14 3.6 100.82 BASE_312 TRUE Temperature < 130 COBST_809 100 0.30 1.14 3.9 91.194 BASE_312 TRUE Temperature < 130 COBST_809 100 0.30 1.14 4.2 84.456 BASE_312 TRUE Temperature < 130 COBST_809 100 0.30 1.14 4.5 77.93 BASE_312 TRUE Temperature < 130 COBST_809 100 0.30 1.14 4.8 72.592 BASE_312 TRUE Temperature < 130 COBST_809 100 0.30 1.14 5.1 67.397 BASE_312 TRUE Temperature < 130 COBST_809 100 0.30 1.14 5.4 62.75 BASE_312 TRUE Temperature < 130 COBST_809 100 0.30 1.14 5.7 59.553 BASE_312 TRUE Temperature < 130 COBST_809 100 0.30 1.14 6 56.916 BASE_312 TRUE Temperature < 130 COBST_815 50 0.30 1.98 2.4 238.53 BASE_322 FALSE Not FilteredOBST_815 50 0.30 1.98 2.7 142.51 BASE_322 FALSE Not FilteredOBST_815 50 0.30 1.98 3 107.22 BASE_322 TRUE Temperature < 130 COBST_815 50 0.30 1.98 3.3 93.883 BASE_322 TRUE Temperature < 130 COBST_815 50 0.30 1.98 3.6 86.855 BASE_322 TRUE Temperature < 130 COBST_815 50 0.30 1.98 3.9 78.339 BASE_322 TRUE Temperature < 130 COBST_815 50 0.30 1.98 4.2 71.221 BASE_322 TRUE Temperature < 130 COBST_815 50 0.30 1.98 4.5 63.611 BASE_322 TRUE Temperature < 130 COBST_815 50 0.30 1.98 4.8 58.549 BASE_322 TRUE Temperature < 130 COBST_815 50 0.30 1.98 5.1 55.323 BASE_322 TRUE Temperature < 130 COBST_815 50 0.30 1.98 5.4 51.364 BASE_322 TRUE Temperature < 130 C

E-35 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

OBST_815 50 0.30 1.98 5.7 47.838 BASE_322 TRUE Temperature < 130 C

OBST_815 50 0.30 1.98 6 45.651 BASE_322 TRUE Temperature < 130 COBST_816 100 0.30 1.98 2.4 434.45 BASE_323 FALSE Not FilteredOBST_816 100 0.30 1.98 2.7 227.23 BASE_323 FALSE Not FilteredOBST_816 100 0.30 1.98 3 170.7 BASE_323 FALSE Not FilteredOBST_816 100 0.30 1.98 3.3 145.87 BASE_323 FALSE Not FilteredOBST_816 100 0.30 1.98 3.6 130.11 BASE_323 FALSE Not FilteredOBST_816 100 0.30 1.98 3.9 116.02 BASE_323 TRUE Temperature < 130 COBST_816 100 0.30 1.98 4.2 104.88 BASE_323 TRUE Temperature < 130 COBST_816 100 0.30 1.98 4.5 91.788 BASE_323 TRUE Temperature < 130 COBST_816 100 0.30 1.98 4.8 84.026 BASE_323 TRUE Temperature < 130 COBST_816 100 0.30 1.98 5.1 78.137 BASE_323 TRUE Temperature < 130 COBST_816 100 0.30 1.98 5.4 71.948 BASE_323 TRUE Temperature < 130 COBST_816 100 0.30 1.98 5.7 66.311 BASE_323 TRUE Temperature < 130 COBST_816 100 0.30 1.98 6 62.282 BASE_323 TRUE Temperature < 130 COBST_866 200 0.61 0.30 2.4 164.84 BASE_302 TRUE Source Located 1 ft. above GroundOBST_866 200 0.61 0.30 2.7 132.51 BASE_302 TRUE Source Located 1 ft. above GroundOBST_866 200 0.61 0.30 3 107.21 BASE_302 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_866 200 0.61 0.30 3.3 95.331 BASE_302 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_866 200 0.61 0.30 3.6 91.403 BASE_302 TRUE Temperature < 130 C , Source

E-36 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

Located 1 ft. above Ground

OBST_866 200 0.61 0.30 3.9 87.841 BASE_302 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_866 200 0.61 0.30 4.2 85.424 BASE_302 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_866 200 0.61 0.30 4.5 81.446 BASE_302 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_866 200 0.61 0.30 4.8 77.871 BASE_302 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_866 200 0.61 0.30 5.1 74.707 BASE_302 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_866 200 0.61 0.30 5.4 70.967 BASE_302 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_866 200 0.61 0.30 5.7 67.65 BASE_302 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_866 200 0.61 0.30 6 65.534 BASE_302 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_867 300 0.61 0.30 2.4 222.46 BASE_303 TRUE Source Located 1 ft. above GroundOBST_867 300 0.61 0.30 2.7 180.68 BASE_303 TRUE Source Located 1 ft. above GroundOBST_867 300 0.61 0.30 3 140.38 BASE_303 TRUE Source Located 1 ft. above GroundOBST_867 300 0.61 0.30 3.3 122.94 BASE_303 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_867 300 0.61 0.30 3.6 116.1 BASE_303 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_867 300 0.61 0.30 3.9 110.06 BASE_303 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

E-37 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

OBST_867 300 0.61 0.30 4.2 105.24 BASE_303 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_867 300 0.61 0.30 4.5 99.731 BASE_303 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_867 300 0.61 0.30 4.8 95.923 BASE_303 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_867 300 0.61 0.30 5.1 91.96 BASE_303 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_867 300 0.61 0.30 5.4 86.163 BASE_303 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_867 300 0.61 0.30 5.7 81.681 BASE_303 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_867 300 0.61 0.30 6 78.494 BASE_303 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_868 400 0.61 0.30 2.4 291.34 BASE_304 TRUE Source Located 1 ft. above GroundOBST_868 400 0.61 0.30 2.7 240.71 BASE_304 TRUE Source Located 1 ft. above GroundOBST_868 400 0.61 0.30 3 182.9 BASE_304 TRUE Source Located 1 ft. above GroundOBST_868 400 0.61 0.30 3.3 153 BASE_304 TRUE Source Located 1 ft. above GroundOBST_868 400 0.61 0.30 3.6 139.81 BASE_304 TRUE Source Located 1 ft. above GroundOBST_868 400 0.61 0.30 3.9 130.81 BASE_304 TRUE Source Located 1 ft. above GroundOBST_868 400 0.61 0.30 4.2 123.93 BASE_304 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_868 400 0.61 0.30 4.5 117.05 BASE_304 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_868 400 0.61 0.30 4.8 111.78 BASE_304 TRUE Temperature < 130 C , Source

E-38 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

Located 1 ft. above Ground

OBST_868 400 0.61 0.30 5.1 107.26 BASE_304 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_868 400 0.61 0.30 5.4 101.33 BASE_304 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_868 400 0.61 0.30 5.7 97.187 BASE_304 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_868 400 0.61 0.30 6 92.575 BASE_304 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_869 500 0.61 0.30 2.4 360.38 BASE_305 TRUE Source Located 1 ft. above GroundOBST_869 500 0.61 0.30 2.7 296.38 BASE_305 TRUE Source Located 1 ft. above GroundOBST_869 500 0.61 0.30 3 226.34 BASE_305 TRUE Source Located 1 ft. above GroundOBST_869 500 0.61 0.30 3.3 187.21 BASE_305 TRUE Source Located 1 ft. above GroundOBST_869 500 0.61 0.30 3.6 176.3 BASE_305 TRUE Source Located 1 ft. above GroundOBST_869 500 0.61 0.30 3.9 161.36 BASE_305 TRUE Source Located 1 ft. above GroundOBST_869 500 0.61 0.30 4.2 151.9 BASE_305 TRUE Source Located 1 ft. above GroundOBST_869 500 0.61 0.30 4.5 142.66 BASE_305 TRUE Source Located 1 ft. above GroundOBST_869 500 0.61 0.30 4.8 135.24 BASE_305 TRUE Source Located 1 ft. above GroundOBST_869 500 0.61 0.30 5.1 128.53 BASE_305 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_869 500 0.61 0.30 5.4 120.48 BASE_305 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_869 500 0.61 0.30 5.7 112.01 BASE_305 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

E-39 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

OBST_869 500 0.61 0.30 6 105.22 BASE_305 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_870 600 0.61 0.30 2.4 444.1 BASE_306 TRUE Source Located 1 ft. above GroundOBST_870 600 0.61 0.30 2.7 366.54 BASE_306 TRUE Source Located 1 ft. above GroundOBST_870 600 0.61 0.30 3 267.05 BASE_306 TRUE Source Located 1 ft. above GroundOBST_870 600 0.61 0.30 3.3 208.14 BASE_306 TRUE Source Located 1 ft. above GroundOBST_870 600 0.61 0.30 3.6 196.87 BASE_306 TRUE Source Located 1 ft. above GroundOBST_870 600 0.61 0.30 3.9 187.62 BASE_306 TRUE Source Located 1 ft. above GroundOBST_870 600 0.61 0.30 4.2 177.69 BASE_306 TRUE Source Located 1 ft. above GroundOBST_870 600 0.61 0.30 4.5 166.61 BASE_306 TRUE Source Located 1 ft. above GroundOBST_870 600 0.61 0.30 4.8 156.15 BASE_306 TRUE Source Located 1 ft. above GroundOBST_870 600 0.61 0.30 5.1 146.03 BASE_306 TRUE Source Located 1 ft. above GroundOBST_870 600 0.61 0.30 5.4 136.86 BASE_306 TRUE Source Located 1 ft. above GroundOBST_870 600 0.61 0.30 5.7 127.13 BASE_306 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_870 600 0.61 0.30 6 118.31 BASE_306 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_873 200 0.61 1.14 2.4 252.79 BASE_313 FALSE Not FilteredOBST_873 200 0.61 1.14 2.7 178.78 BASE_313 FALSE Not FilteredOBST_873 200 0.61 1.14 3 139.76 BASE_313 FALSE Not FilteredOBST_873 200 0.61 1.14 3.3 114.89 BASE_313 TRUE Temperature < 130 COBST_873 200 0.61 1.14 3.6 109.86 BASE_313 TRUE Temperature < 130 C

E-40 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

OBST_873 200 0.61 1.14 3.9 105.51 BASE_313 TRUE Temperature < 130 C

OBST_873 200 0.61 1.14 4.2 98.993 BASE_313 TRUE Temperature < 130 COBST_873 200 0.61 1.14 4.5 92.343 BASE_313 TRUE Temperature < 130 COBST_873 200 0.61 1.14 4.8 91.944 BASE_313 TRUE Temperature < 130 COBST_873 200 0.61 1.14 5.1 88.838 BASE_313 TRUE Temperature < 130 COBST_873 200 0.61 1.14 5.4 79.482 BASE_313 TRUE Temperature < 130 COBST_873 200 0.61 1.14 5.7 75.88 BASE_313 TRUE Temperature < 130 COBST_873 200 0.61 1.14 6 73.076 BASE_313 TRUE Temperature < 130 COBST_874 300 0.61 1.14 2.4 368.65 BASE_314 FALSE Not FilteredOBST_874 300 0.61 1.14 2.7 245.86 BASE_314 FALSE Not FilteredOBST_874 300 0.61 1.14 3 184.52 BASE_314 FALSE Not FilteredOBST_874 300 0.61 1.14 3.3 156.76 BASE_314 FALSE Not FilteredOBST_874 300 0.61 1.14 3.6 146.93 BASE_314 FALSE Not FilteredOBST_874 300 0.61 1.14 3.9 141.51 BASE_314 FALSE Not FilteredOBST_874 300 0.61 1.14 4.2 136.21 BASE_314 FALSE Not FilteredOBST_874 300 0.61 1.14 4.5 128.41 BASE_314 TRUE Temperature < 130 COBST_874 300 0.61 1.14 4.8 121.42 BASE_314 TRUE Temperature < 130 COBST_874 300 0.61 1.14 5.1 113.6 BASE_314 TRUE Temperature < 130 COBST_874 300 0.61 1.14 5.4 105.07 BASE_314 TRUE Temperature < 130 COBST_874 300 0.61 1.14 5.7 97.706 BASE_314 TRUE Temperature < 130 COBST_874 300 0.61 1.14 6 93.251 BASE_314 TRUE Temperature < 130 C

E-41 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

OBST_875 400 0.61 1.14 2.4 527.19 BASE_315 FALSE Not Filtered

OBST_875 400 0.61 1.14 2.7 351.26 BASE_315 FALSE Not FilteredOBST_875 400 0.61 1.14 3 254.18 BASE_315 FALSE Not FilteredOBST_875 400 0.61 1.14 3.3 201.11 BASE_315 FALSE Not FilteredOBST_875 400 0.61 1.14 3.6 188.81 BASE_315 FALSE Not FilteredOBST_875 400 0.61 1.14 3.9 177.84 BASE_315 FALSE Not FilteredOBST_875 400 0.61 1.14 4.2 169.98 BASE_315 FALSE Not FilteredOBST_875 400 0.61 1.14 4.5 162.77 BASE_315 FALSE Not FilteredOBST_875 400 0.61 1.14 4.8 154.43 BASE_315 FALSE Not FilteredOBST_875 400 0.61 1.14 5.1 146.06 BASE_315 FALSE Not FilteredOBST_875 400 0.61 1.14 5.4 135.51 BASE_315 FALSE Not FilteredOBST_875 400 0.61 1.14 5.7 124.66 BASE_315 TRUE Temperature < 130 COBST_875 400 0.61 1.14 6 117.1 BASE_315 TRUE Temperature < 130 COBST_876 500 0.61 1.14 2.4 670.82 BASE_316 FALSE Not FilteredOBST_876 500 0.61 1.14 2.7 454.57 BASE_316 FALSE Not FilteredOBST_876 500 0.61 1.14 3 325.36 BASE_316 FALSE Not FilteredOBST_876 500 0.61 1.14 3.3 246.23 BASE_316 FALSE Not FilteredOBST_876 500 0.61 1.14 3.6 230.64 BASE_316 FALSE Not FilteredOBST_876 500 0.61 1.14 3.9 220.37 BASE_316 FALSE Not FilteredOBST_876 500 0.61 1.14 4.2 209.08 BASE_316 FALSE Not FilteredOBST_876 500 0.61 1.14 4.5 196.49 BASE_316 FALSE Not Filtered

E-42 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

OBST_876 500 0.61 1.14 4.8 185.18 BASE_316 FALSE Not Filtered

OBST_876 500 0.61 1.14 5.1 174.3 BASE_316 FALSE Not FilteredOBST_876 500 0.61 1.14 5.4 162.71 BASE_316 FALSE Not FilteredOBST_876 500 0.61 1.14 5.7 150.55 BASE_316 FALSE Not FilteredOBST_876 500 0.61 1.14 6 140.12 BASE_316 FALSE Not FilteredOBST_877 600 0.61 1.14 2.4 805.93 BASE_317 TRUE Temperature > 800 COBST_877 600 0.61 1.14 2.7 574.34 BASE_317 FALSE Not FilteredOBST_877 600 0.61 1.14 3 403.91 BASE_317 FALSE Not FilteredOBST_877 600 0.61 1.14 3.3 299.89 BASE_317 FALSE Not FilteredOBST_877 600 0.61 1.14 3.6 267.2 BASE_317 FALSE Not FilteredOBST_877 600 0.61 1.14 3.9 252.02 BASE_317 FALSE Not FilteredOBST_877 600 0.61 1.14 4.2 238.02 BASE_317 FALSE Not FilteredOBST_877 600 0.61 1.14 4.5 220.1 BASE_317 FALSE Not FilteredOBST_877 600 0.61 1.14 4.8 206.1 BASE_317 FALSE Not FilteredOBST_877 600 0.61 1.14 5.1 194.77 BASE_317 FALSE Not FilteredOBST_877 600 0.61 1.14 5.4 183.24 BASE_317 FALSE Not FilteredOBST_877 600 0.61 1.14 5.7 170.25 BASE_317 FALSE Not FilteredOBST_877 600 0.61 1.14 6 157.23 BASE_317 FALSE Not FilteredOBST_880 200 0.61 1.98 2.4 604.85 BASE_324 FALSE Not FilteredOBST_880 200 0.61 1.98 2.7 379.73 BASE_324 FALSE Not FilteredOBST_880 200 0.61 1.98 3 281.92 BASE_324 FALSE Not Filtered

E-43 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

OBST_880 200 0.61 1.98 3.3 206.03 BASE_324 FALSE Not Filtered

OBST_880 200 0.61 1.98 3.6 163.97 BASE_324 FALSE Not FilteredOBST_880 200 0.61 1.98 3.9 135.19 BASE_324 FALSE Not FilteredOBST_880 200 0.61 1.98 4.2 120.13 BASE_324 TRUE Temperature < 130 COBST_880 200 0.61 1.98 4.5 114.48 BASE_324 TRUE Temperature < 130 COBST_880 200 0.61 1.98 4.8 108.02 BASE_324 TRUE Temperature < 130 COBST_880 200 0.61 1.98 5.1 101.9 BASE_324 TRUE Temperature < 130 COBST_880 200 0.61 1.98 5.4 92.323 BASE_324 TRUE Temperature < 130 COBST_880 200 0.61 1.98 5.7 84.71 BASE_324 TRUE Temperature < 130 COBST_880 200 0.61 1.98 6 79.047 BASE_324 TRUE Temperature < 130 COBST_881 300 0.61 1.98 2.4 756.24 BASE_325 FALSE Not FilteredOBST_881 300 0.61 1.98 2.7 518.35 BASE_325 FALSE Not FilteredOBST_881 300 0.61 1.98 3 352.98 BASE_325 FALSE Not FilteredOBST_881 300 0.61 1.98 3.3 273.32 BASE_325 FALSE Not FilteredOBST_881 300 0.61 1.98 3.6 234.24 BASE_325 FALSE Not FilteredOBST_881 300 0.61 1.98 3.9 213.54 BASE_325 FALSE Not FilteredOBST_881 300 0.61 1.98 4.2 199.06 BASE_325 FALSE Not FilteredOBST_881 300 0.61 1.98 4.5 179.94 BASE_325 FALSE Not FilteredOBST_881 300 0.61 1.98 4.8 165.89 BASE_325 FALSE Not FilteredOBST_881 300 0.61 1.98 5.1 153.19 BASE_325 FALSE Not FilteredOBST_881 300 0.61 1.98 5.4 138.07 BASE_325 FALSE Not Filtered

E-44 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

OBST_881 300 0.61 1.98 5.7 124.6 BASE_325 TRUE Temperature < 130 C

OBST_881 300 0.61 1.98 6 114.21 BASE_325 TRUE Temperature < 130 COBST_882 400 0.61 1.98 2.4 894.05 BASE_326 TRUE Temperature > 800 COBST_882 400 0.61 1.98 2.7 596.62 BASE_326 FALSE Not FilteredOBST_882 400 0.61 1.98 3 471.3 BASE_326 FALSE Not FilteredOBST_882 400 0.61 1.98 3.3 398.26 BASE_326 FALSE Not FilteredOBST_882 400 0.61 1.98 3.6 356 BASE_326 FALSE Not FilteredOBST_882 400 0.61 1.98 3.9 315.04 BASE_326 FALSE Not FilteredOBST_882 400 0.61 1.98 4.2 285.76 BASE_326 FALSE Not FilteredOBST_882 400 0.61 1.98 4.5 253.9 BASE_326 FALSE Not FilteredOBST_882 400 0.61 1.98 4.8 223.38 BASE_326 FALSE Not FilteredOBST_882 400 0.61 1.98 5.1 200.05 BASE_326 FALSE Not FilteredOBST_882 400 0.61 1.98 5.4 175.4 BASE_326 FALSE Not FilteredOBST_882 400 0.61 1.98 5.7 154.3 BASE_326 FALSE Not FilteredOBST_882 400 0.61 1.98 6 139.3 BASE_326 FALSE Not FilteredOBST_883 500 0.61 1.98 2.4 1025 BASE_327 TRUE Temperature > 800 COBST_883 500 0.61 1.98 2.7 767.26 BASE_327 FALSE Not FilteredOBST_883 500 0.61 1.98 3 593.89 BASE_327 FALSE Not FilteredOBST_883 500 0.61 1.98 3.3 517.17 BASE_327 FALSE Not FilteredOBST_883 500 0.61 1.98 3.6 457.04 BASE_327 FALSE Not FilteredOBST_883 500 0.61 1.98 3.9 396.41 BASE_327 FALSE Not Filtered

E-45 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

OBST_883 500 0.61 1.98 4.2 349.43 BASE_327 FALSE Not Filtered

OBST_883 500 0.61 1.98 4.5 305.67 BASE_327 FALSE Not FilteredOBST_883 500 0.61 1.98 4.8 272.27 BASE_327 FALSE Not FilteredOBST_883 500 0.61 1.98 5.1 247.61 BASE_327 FALSE Not FilteredOBST_883 500 0.61 1.98 5.4 220 BASE_327 FALSE Not FilteredOBST_883 500 0.61 1.98 5.7 194.5 BASE_327 FALSE Not FilteredOBST_883 500 0.61 1.98 6 175.45 BASE_327 FALSE Not FilteredOBST_884 600 0.61 1.98 2.4 1097.7 BASE_328 TRUE Temperature > 800 COBST_884 600 0.61 1.98 2.7 859.9 BASE_328 TRUE Temperature > 800 COBST_884 600 0.61 1.98 3 742.72 BASE_328 FALSE Not FilteredOBST_884 600 0.61 1.98 3.3 652.09 BASE_328 FALSE Not FilteredOBST_884 600 0.61 1.98 3.6 576.72 BASE_328 FALSE Not FilteredOBST_884 600 0.61 1.98 3.9 500.69 BASE_328 FALSE Not FilteredOBST_884 600 0.61 1.98 4.2 448.14 BASE_328 FALSE Not FilteredOBST_884 600 0.61 1.98 4.5 394.23 BASE_328 FALSE Not FilteredOBST_884 600 0.61 1.98 4.8 347.72 BASE_328 FALSE Not FilteredOBST_884 600 0.61 1.98 5.1 304.84 BASE_328 FALSE Not FilteredOBST_884 600 0.61 1.98 5.4 262.25 BASE_328 FALSE Not FilteredOBST_884 600 0.61 1.98 5.7 230.22 BASE_328 FALSE Not FilteredOBST_884 600 0.61 1.98 6 206.23 BASE_328 FALSE Not FilteredOBST_930 300 0.91 0.30 2.4 160.04 BASE_307 TRUE Source Located 1 ft. above Ground

E-46 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

OBST_930 300 0.91 0.30 2.7 128.35 BASE_307 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_930 300 0.91 0.30 3 99.968 BASE_307 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_930 300 0.91 0.30 3.3 87.329 BASE_307 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_930 300 0.91 0.30 3.6 84.8 BASE_307 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_930 300 0.91 0.30 3.9 81.026 BASE_307 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_930 300 0.91 0.30 4.2 79.399 BASE_307 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_930 300 0.91 0.30 4.5 77.372 BASE_307 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_930 300 0.91 0.30 4.8 75.677 BASE_307 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_930 300 0.91 0.30 5.1 73.803 BASE_307 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_930 300 0.91 0.30 5.4 71.873 BASE_307 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_930 300 0.91 0.30 5.7 69.841 BASE_307 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_930 300 0.91 0.30 6 67.783 BASE_307 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_931 400 0.91 0.30 2.4 200.28 BASE_308 TRUE Source Located 1 ft. above GroundOBST_931 400 0.91 0.30 2.7 159.04 BASE_308 TRUE Source Located 1 ft. above Ground

E-47 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

OBST_931 400 0.91 0.30 3 127.39 BASE_308 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_931 400 0.91 0.30 3.3 109.61 BASE_308 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_931 400 0.91 0.30 3.6 104.4 BASE_308 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_931 400 0.91 0.30 3.9 100.86 BASE_308 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_931 400 0.91 0.30 4.2 97.017 BASE_308 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_931 400 0.91 0.30 4.5 93.238 BASE_308 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_931 400 0.91 0.30 4.8 90.169 BASE_308 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_931 400 0.91 0.30 5.1 86.888 BASE_308 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_931 400 0.91 0.30 5.4 83.318 BASE_308 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_931 400 0.91 0.30 5.7 80.717 BASE_308 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_931 400 0.91 0.30 6 77.924 BASE_308 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_932 500 0.91 0.30 2.4 252.84 BASE_309 TRUE Source Located 1 ft. above GroundOBST_932 500 0.91 0.30 2.7 197.23 BASE_309 TRUE Source Located 1 ft. above GroundOBST_932 500 0.91 0.30 3 155.39 BASE_309 TRUE Source Located 1 ft. above GroundOBST_932 500 0.91 0.30 3.3 133.65 BASE_309 TRUE Source Located 1 ft. above Ground

E-48 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

OBST_932 500 0.91 0.30 3.6 125.14 BASE_309 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_932 500 0.91 0.30 3.9 120.05 BASE_309 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_932 500 0.91 0.30 4.2 115.56 BASE_309 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_932 500 0.91 0.30 4.5 111.08 BASE_309 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_932 500 0.91 0.30 4.8 108.49 BASE_309 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_932 500 0.91 0.30 5.1 106.33 BASE_309 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_932 500 0.91 0.30 5.4 103.09 BASE_309 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_932 500 0.91 0.30 5.7 99.274 BASE_309 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_932 500 0.91 0.30 6 95.942 BASE_309 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_933 600 0.91 0.30 2.4 305.13 BASE_310 TRUE Source Located 1 ft. above GroundOBST_933 600 0.91 0.30 2.7 237.66 BASE_310 TRUE Source Located 1 ft. above GroundOBST_933 600 0.91 0.30 3 189.79 BASE_310 TRUE Source Located 1 ft. above GroundOBST_933 600 0.91 0.30 3.3 160.75 BASE_310 TRUE Source Located 1 ft. above GroundOBST_933 600 0.91 0.30 3.6 148.5 BASE_310 TRUE Source Located 1 ft. above GroundOBST_933 600 0.91 0.30 3.9 139.86 BASE_310 TRUE Source Located 1 ft. above GroundOBST_933 600 0.91 0.30 4.2 135 BASE_310 TRUE Source Located 1 ft. above Ground

E-49 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

OBST_933 600 0.91 0.30 4.5 130.94 BASE_310 TRUE Source Located 1 ft. above Ground

OBST_933 600 0.91 0.30 4.8 126.3 BASE_310 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_933 600 0.91 0.30 5.1 121.48 BASE_310 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_933 600 0.91 0.30 5.4 116.38 BASE_310 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_933 600 0.91 0.30 5.7 112.08 BASE_310 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_933 600 0.91 0.30 6 108.23 BASE_310 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

OBST_937 300 0.91 1.14 2.4 256.44 BASE_318 FALSE Not FilteredOBST_937 300 0.91 1.14 2.7 190.78 BASE_318 FALSE Not FilteredOBST_937 300 0.91 1.14 3 146.6 BASE_318 FALSE Not FilteredOBST_937 300 0.91 1.14 3.3 128.92 BASE_318 TRUE Temperature < 130 COBST_937 300 0.91 1.14 3.6 122.18 BASE_318 TRUE Temperature < 130 COBST_937 300 0.91 1.14 3.9 115.48 BASE_318 TRUE Temperature < 130 COBST_937 300 0.91 1.14 4.2 110.78 BASE_318 TRUE Temperature < 130 COBST_937 300 0.91 1.14 4.5 105.77 BASE_318 TRUE Temperature < 130 COBST_937 300 0.91 1.14 4.8 101.51 BASE_318 TRUE Temperature < 130 COBST_937 300 0.91 1.14 5.1 97.445 BASE_318 TRUE Temperature < 130 COBST_937 300 0.91 1.14 5.4 93.173 BASE_318 TRUE Temperature < 130 COBST_937 300 0.91 1.14 5.7 88.159 BASE_318 TRUE Temperature < 130 C

E-50 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

OBST_937 300 0.91 1.14 6 84.368 BASE_318 TRUE Temperature < 130 C

OBST_938 400 0.91 1.14 2.4 345.72 BASE_319 FALSE Not FilteredOBST_938 400 0.91 1.14 2.7 232.8 BASE_319 FALSE Not FilteredOBST_938 400 0.91 1.14 3 182.85 BASE_319 FALSE Not FilteredOBST_938 400 0.91 1.14 3.3 156.65 BASE_319 FALSE Not FilteredOBST_938 400 0.91 1.14 3.6 147.22 BASE_319 FALSE Not FilteredOBST_938 400 0.91 1.14 3.9 141.22 BASE_319 FALSE Not FilteredOBST_938 400 0.91 1.14 4.2 136.82 BASE_319 FALSE Not FilteredOBST_938 400 0.91 1.14 4.5 130.48 BASE_319 FALSE Not FilteredOBST_938 400 0.91 1.14 4.8 124.77 BASE_319 TRUE Temperature < 130 COBST_938 400 0.91 1.14 5.1 119.2 BASE_319 TRUE Temperature < 130 COBST_938 400 0.91 1.14 5.4 112.58 BASE_319 TRUE Temperature < 130 COBST_938 400 0.91 1.14 5.7 106.5 BASE_319 TRUE Temperature < 130 COBST_938 400 0.91 1.14 6 100.49 BASE_319 TRUE Temperature < 130 COBST_939 500 0.91 1.14 2.4 440.75 BASE_320 FALSE Not FilteredOBST_939 500 0.91 1.14 2.7 305.96 BASE_320 FALSE Not FilteredOBST_939 500 0.91 1.14 3 224.42 BASE_320 FALSE Not FilteredOBST_939 500 0.91 1.14 3.3 186.46 BASE_320 FALSE Not FilteredOBST_939 500 0.91 1.14 3.6 176.39 BASE_320 FALSE Not FilteredOBST_939 500 0.91 1.14 3.9 169.66 BASE_320 FALSE Not FilteredOBST_939 500 0.91 1.14 4.2 164.02 BASE_320 FALSE Not Filtered

E-51 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

OBST_939 500 0.91 1.14 4.5 156.28 BASE_320 FALSE Not Filtered

OBST_939 500 0.91 1.14 4.8 149.36 BASE_320 FALSE Not FilteredOBST_939 500 0.91 1.14 5.1 141.6 BASE_320 FALSE Not FilteredOBST_939 500 0.91 1.14 5.4 132.1 BASE_320 FALSE Not FilteredOBST_939 500 0.91 1.14 5.7 122.61 BASE_320 TRUE Temperature < 130 COBST_939 500 0.91 1.14 6 114.99 BASE_320 TRUE Temperature < 130 COBST_940 600 0.91 1.14 2.4 562.49 BASE_321 FALSE Not FilteredOBST_940 600 0.91 1.14 2.7 385.62 BASE_321 FALSE Not FilteredOBST_940 600 0.91 1.14 3 292.81 BASE_321 FALSE Not FilteredOBST_940 600 0.91 1.14 3.3 240.08 BASE_321 FALSE Not FilteredOBST_940 600 0.91 1.14 3.6 214.75 BASE_321 FALSE Not FilteredOBST_940 600 0.91 1.14 3.9 196.25 BASE_321 FALSE Not FilteredOBST_940 600 0.91 1.14 4.2 187.07 BASE_321 FALSE Not FilteredOBST_940 600 0.91 1.14 4.5 179.33 BASE_321 FALSE Not FilteredOBST_940 600 0.91 1.14 4.8 172.41 BASE_321 FALSE Not FilteredOBST_940 600 0.91 1.14 5.1 165.68 BASE_321 FALSE Not FilteredOBST_940 600 0.91 1.14 5.4 156.24 BASE_321 FALSE Not FilteredOBST_940 600 0.91 1.14 5.7 145.56 BASE_321 FALSE Not FilteredOBST_940 600 0.91 1.14 6 136.35 BASE_321 FALSE Not FilteredOBST_944 300 0.91 1.98 2.4 448.28 BASE_329 FALSE Not FilteredOBST_944 300 0.91 1.98 2.7 294.2 BASE_329 FALSE Not Filtered

E-52 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

OBST_944 300 0.91 1.98 3 230.14 BASE_329 FALSE Not Filtered

OBST_944 300 0.91 1.98 3.3 198.17 BASE_329 FALSE Not FilteredOBST_944 300 0.91 1.98 3.6 190.23 BASE_329 FALSE Not FilteredOBST_944 300 0.91 1.98 3.9 182.18 BASE_329 FALSE Not FilteredOBST_944 300 0.91 1.98 4.2 172.71 BASE_329 FALSE Not FilteredOBST_944 300 0.91 1.98 4.5 161.02 BASE_329 FALSE Not FilteredOBST_944 300 0.91 1.98 4.8 150.26 BASE_329 FALSE Not FilteredOBST_944 300 0.91 1.98 5.1 139.52 BASE_329 FALSE Not FilteredOBST_944 300 0.91 1.98 5.4 127.37 BASE_329 TRUE Temperature < 130 COBST_944 300 0.91 1.98 5.7 116.2 BASE_329 TRUE Temperature < 130 COBST_944 300 0.91 1.98 6 106.93 BASE_329 TRUE Temperature < 130 COBST_945 400 0.91 1.98 2.4 634.19 BASE_330 FALSE Not FilteredOBST_945 400 0.91 1.98 2.7 393.3 BASE_330 FALSE Not FilteredOBST_945 400 0.91 1.98 3 320.01 BASE_330 FALSE Not FilteredOBST_945 400 0.91 1.98 3.3 271.01 BASE_330 FALSE Not FilteredOBST_945 400 0.91 1.98 3.6 256.39 BASE_330 FALSE Not FilteredOBST_945 400 0.91 1.98 3.9 242.45 BASE_330 FALSE Not FilteredOBST_945 400 0.91 1.98 4.2 224.26 BASE_330 FALSE Not FilteredOBST_945 400 0.91 1.98 4.5 202.73 BASE_330 FALSE Not FilteredOBST_945 400 0.91 1.98 4.8 185.73 BASE_330 FALSE Not FilteredOBST_945 400 0.91 1.98 5.1 169.17 BASE_330 FALSE Not Filtered

E-53 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

OBST_945 400 0.91 1.98 5.4 151.88 BASE_330 FALSE Not Filtered

OBST_945 400 0.91 1.98 5.7 135.11 BASE_330 FALSE Not FilteredOBST_945 400 0.91 1.98 6 123.31 BASE_330 TRUE Temperature < 130 COBST_946 500 0.91 1.98 2.4 766.89 BASE_331 FALSE Not FilteredOBST_946 500 0.91 1.98 2.7 474.78 BASE_331 FALSE Not FilteredOBST_946 500 0.91 1.98 3 395.78 BASE_331 FALSE Not FilteredOBST_946 500 0.91 1.98 3.3 350.79 BASE_331 FALSE Not FilteredOBST_946 500 0.91 1.98 3.6 323.72 BASE_331 FALSE Not FilteredOBST_946 500 0.91 1.98 3.9 302.66 BASE_331 FALSE Not FilteredOBST_946 500 0.91 1.98 4.2 280.58 BASE_331 FALSE Not FilteredOBST_946 500 0.91 1.98 4.5 255.83 BASE_331 FALSE Not FilteredOBST_946 500 0.91 1.98 4.8 233.31 BASE_331 FALSE Not FilteredOBST_946 500 0.91 1.98 5.1 210.86 BASE_331 FALSE Not FilteredOBST_946 500 0.91 1.98 5.4 188.4 BASE_331 FALSE Not FilteredOBST_946 500 0.91 1.98 5.7 165.77 BASE_331 FALSE Not FilteredOBST_946 500 0.91 1.98 6 150.43 BASE_331 FALSE Not FilteredOBST_947 600 0.91 1.98 2.4 908.27 BASE_332 TRUE Temperature > 800 COBST_947 600 0.91 1.98 2.7 586.87 BASE_332 FALSE Not FilteredOBST_947 600 0.91 1.98 3 489.56 BASE_332 FALSE Not FilteredOBST_947 600 0.91 1.98 3.3 448.06 BASE_332 FALSE Not FilteredOBST_947 600 0.91 1.98 3.6 410.02 BASE_332 FALSE Not Filtered

E-54 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

OBST_947 600 0.91 1.98 3.9 371.04 BASE_332 FALSE Not Filtered

OBST_947 600 0.91 1.98 4.2 338.75 BASE_332 FALSE Not FilteredOBST_947 600 0.91 1.98 4.5 299.61 BASE_332 FALSE Not FilteredOBST_947 600 0.91 1.98 4.8 266.02 BASE_332 FALSE Not FilteredOBST_947 600 0.91 1.98 5.1 237.54 BASE_332 FALSE Not FilteredOBST_947 600 0.91 1.98 5.4 209.53 BASE_332 FALSE Not FilteredOBST_947 600 0.91 1.98 5.7 184.54 BASE_332 FALSE Not FilteredOBST_947 600 0.91 1.98 6 167.13 BASE_332 FALSE Not Filtered

THREEWALL_1057 1000 0.91 0.30 2.4 621.54 BASE_404 TRUE Source Located 1 ft. above GroundTHREEWALL_1057 1000 0.91 0.30 2.7 405.17 BASE_404 TRUE Source Located 1 ft. above GroundTHREEWALL_1057 1000 0.91 0.30 3 294.64 BASE_404 TRUE Source Located 1 ft. above GroundTHREEWALL_1057 1000 0.91 0.30 3.3 232.75 BASE_404 TRUE Source Located 1 ft. above GroundTHREEWALL_1057 1000 0.91 0.30 3.6 196.9 BASE_404 TRUE Source Located 1 ft. above GroundTHREEWALL_1057 1000 0.91 0.30 3.9 169.25 BASE_404 TRUE Source Located 1 ft. above GroundTHREEWALL_1057 1000 0.91 0.30 4.2 152.11 BASE_404 TRUE Source Located 1 ft. above GroundTHREEWALL_1057 1000 0.91 0.30 4.5 138.74 BASE_404 TRUE Source Located 1 ft. above GroundTHREEWALL_1057 1000 0.91 0.30 4.8 131.68 BASE_404 TRUE Source Located 1 ft. above GroundTHREEWALL_1057 1000 0.91 0.30 5.1 121.29 BASE_404 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_1057 1000 0.91 0.30 5.4 109.71 BASE_404 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_1057 1000 0.91 0.30 5.7 103.98 BASE_404 TRUE Temperature < 130 C , Source

E-55 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

Located 1 ft. above Ground

THREEWALL_1057 1000 0.91 0.30 6 99.867 BASE_404 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_1058 1000 0.91 1.14 2.4 889.87 BASE_400 TRUE Temperature > 800 CTHREEWALL_1058 1000 0.91 1.14 2.7 640.76 BASE_400 FALSE Not FilteredTHREEWALL_1058 1000 0.91 1.14 3 504.86 BASE_400 FALSE Not FilteredTHREEWALL_1058 1000 0.91 1.14 3.3 401.71 BASE_400 FALSE Not FilteredTHREEWALL_1058 1000 0.91 1.14 3.6 339.8 BASE_400 FALSE Not FilteredTHREEWALL_1058 1000 0.91 1.14 3.9 284.72 BASE_400 FALSE Not FilteredTHREEWALL_1058 1000 0.91 1.14 4.2 250.82 BASE_400 FALSE Not FilteredTHREEWALL_1058 1000 0.91 1.14 4.5 215.58 BASE_400 FALSE Not FilteredTHREEWALL_1058 1000 0.91 1.14 4.8 188.42 BASE_400 FALSE Not FilteredTHREEWALL_1058 1000 0.91 1.14 5.1 166.49 BASE_400 FALSE Not FilteredTHREEWALL_1058 1000 0.91 1.14 5.4 146.15 BASE_400 FALSE Not FilteredTHREEWALL_1058 1000 0.91 1.14 5.7 135.05 BASE_400 FALSE Not FilteredTHREEWALL_1058 1000 0.91 1.14 6 126.88 BASE_400 TRUE Temperature < 130 CTHREEWALL_1059 1000 0.91 1.98 2.4 1062.2 BASE_401 TRUE Temperature > 800 CTHREEWALL_1059 1000 0.91 1.98 2.7 1070.8 BASE_401 TRUE Temperature > 800 CTHREEWALL_1059 1000 0.91 1.98 3 1025.2 BASE_401 TRUE Temperature > 800 CTHREEWALL_1059 1000 0.91 1.98 3.3 921.05 BASE_401 TRUE Temperature > 800 CTHREEWALL_1059 1000 0.91 1.98 3.6 827.48 BASE_401 TRUE Temperature > 800 CTHREEWALL_1059 1000 0.91 1.98 3.9 666.54 BASE_401 FALSE Not Filtered

E-56 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

THREEWALL_1059 1000 0.91 1.98 4.2 547.72 BASE_401 FALSE Not Filtered

THREEWALL_1059 1000 0.91 1.98 4.5 431.6 BASE_401 FALSE Not FilteredTHREEWALL_1059 1000 0.91 1.98 4.8 354.89 BASE_401 FALSE Not FilteredTHREEWALL_1059 1000 0.91 1.98 5.1 306.67 BASE_401 FALSE Not FilteredTHREEWALL_1059 1000 0.91 1.98 5.4 264.2 BASE_401 FALSE Not FilteredTHREEWALL_1059 1000 0.91 1.98 5.7 227.16 BASE_401 FALSE Not FilteredTHREEWALL_1059 1000 0.91 1.98 6 206.73 BASE_401 FALSE Not FilteredTHREEWALL_1066 1000 1.22 0.30 2.4 429.91 BASE_405 TRUE Source Located 1 ft. above GroundTHREEWALL_1066 1000 1.22 0.30 2.7 269.44 BASE_405 TRUE Source Located 1 ft. above GroundTHREEWALL_1066 1000 1.22 0.30 3 211.98 BASE_405 TRUE Source Located 1 ft. above GroundTHREEWALL_1066 1000 1.22 0.30 3.3 185.78 BASE_405 TRUE Source Located 1 ft. above GroundTHREEWALL_1066 1000 1.22 0.30 3.6 165.07 BASE_405 TRUE Source Located 1 ft. above GroundTHREEWALL_1066 1000 1.22 0.30 3.9 141.74 BASE_405 TRUE Source Located 1 ft. above GroundTHREEWALL_1066 1000 1.22 0.30 4.2 133.48 BASE_405 TRUE Source Located 1 ft. above GroundTHREEWALL_1066 1000 1.22 0.30 4.5 125.97 BASE_405 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_1066 1000 1.22 0.30 4.8 115.34 BASE_405 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_1066 1000 1.22 0.30 5.1 107.39 BASE_405 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_1066 1000 1.22 0.30 5.4 99.885 BASE_405 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_1066 1000 1.22 0.30 5.7 93.595 BASE_405 TRUE Temperature < 130 C , Source

E-57 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

Located 1 ft. above Ground

THREEWALL_1066 1000 1.22 0.30 6 89.031 BASE_405 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_1067 1000 1.22 1.14 2.4 683.06 BASE_402 FALSE Not FilteredTHREEWALL_1067 1000 1.22 1.14 2.7 460.84 BASE_402 FALSE Not FilteredTHREEWALL_1067 1000 1.22 1.14 3 363.31 BASE_402 FALSE Not FilteredTHREEWALL_1067 1000 1.22 1.14 3.3 299.81 BASE_402 FALSE Not FilteredTHREEWALL_1067 1000 1.22 1.14 3.6 255.01 BASE_402 FALSE Not FilteredTHREEWALL_1067 1000 1.22 1.14 3.9 210.95 BASE_402 FALSE Not FilteredTHREEWALL_1067 1000 1.22 1.14 4.2 187.89 BASE_402 FALSE Not FilteredTHREEWALL_1067 1000 1.22 1.14 4.5 161.24 BASE_402 FALSE Not FilteredTHREEWALL_1067 1000 1.22 1.14 4.8 145.62 BASE_402 FALSE Not FilteredTHREEWALL_1067 1000 1.22 1.14 5.1 132.94 BASE_402 FALSE Not FilteredTHREEWALL_1067 1000 1.22 1.14 5.4 122.79 BASE_402 TRUE Temperature < 130 CTHREEWALL_1067 1000 1.22 1.14 5.7 114.24 BASE_402 TRUE Temperature < 130 CTHREEWALL_1067 1000 1.22 1.14 6 108.6 BASE_402 TRUE Temperature < 130 CTHREEWALL_1068 1000 1.22 1.98 2.4 1071.1 BASE_403 TRUE Temperature > 800 CTHREEWALL_1068 1000 1.22 1.98 2.7 1067.8 BASE_403 TRUE Temperature > 800 CTHREEWALL_1068 1000 1.22 1.98 3 1011.9 BASE_403 TRUE Temperature > 800 CTHREEWALL_1068 1000 1.22 1.98 3.3 858.81 BASE_403 TRUE Temperature > 800 CTHREEWALL_1068 1000 1.22 1.98 3.6 679.45 BASE_403 FALSE Not FilteredTHREEWALL_1068 1000 1.22 1.98 3.9 516.14 BASE_403 FALSE Not Filtered

E-58 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

THREEWALL_1068 1000 1.22 1.98 4.2 417.07 BASE_403 FALSE Not Filtered

THREEWALL_1068 1000 1.22 1.98 4.5 338.85 BASE_403 FALSE Not FilteredTHREEWALL_1068 1000 1.22 1.98 4.8 292.29 BASE_403 FALSE Not FilteredTHREEWALL_1068 1000 1.22 1.98 5.1 254.15 BASE_403 FALSE Not FilteredTHREEWALL_1068 1000 1.22 1.98 5.4 224.04 BASE_403 FALSE Not FilteredTHREEWALL_1068 1000 1.22 1.98 5.7 199.74 BASE_403 FALSE Not FilteredTHREEWALL_1068 1000 1.22 1.98 6 181.86 BASE_403 FALSE Not Filtered

THREEWALL_843 50 0.30 0.30 2.4 106.22 BASE_300 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_843 50 0.30 0.30 2.7 69.818 BASE_300 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_843 50 0.30 0.30 3 58.899 BASE_300 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_843 50 0.30 0.30 3.3 50.866 BASE_300 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_843 50 0.30 0.30 3.6 46.842 BASE_300 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_843 50 0.30 0.30 3.9 43.306 BASE_300 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_843 50 0.30 0.30 4.2 40.867 BASE_300 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_844 100 0.30 0.30 2.4 151.65 BASE_301 TRUE Source Located 1 ft. above GroundTHREEWALL_844 100 0.30 0.30 2.7 99.551 BASE_301 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

E-59 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

THREEWALL_844 100 0.30 0.30 3 85.142 BASE_301 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_844 100 0.30 0.30 3.3 73.312 BASE_301 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_844 100 0.30 0.30 3.6 64.692 BASE_301 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_844 100 0.30 0.30 3.9 59.171 BASE_301 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_844 100 0.30 0.30 4.2 54.595 BASE_301 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_844 100 0.30 0.30 4.5 51.396 BASE_301 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_844 100 0.30 0.30 4.8 47.861 BASE_301 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_844 100 0.30 0.30 5.1 45.037 BASE_301 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_844 100 0.30 0.30 5.4 42.201 BASE_301 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_844 100 0.30 0.30 5.7 40.709 BASE_301 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_850 50 0.30 1.14 2.4 175.3 BASE_311 FALSE Not FilteredTHREEWALL_850 50 0.30 1.14 2.7 107.81 BASE_311 TRUE Temperature < 130 CTHREEWALL_850 50 0.30 1.14 3 89.936 BASE_311 TRUE Temperature < 130 CTHREEWALL_850 50 0.30 1.14 3.3 75.701 BASE_311 TRUE Temperature < 130 CTHREEWALL_850 50 0.30 1.14 3.6 66.33 BASE_311 TRUE Temperature < 130 C

E-60 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

THREEWALL_850 50 0.30 1.14 3.9 58.179 BASE_311 TRUE Temperature < 130 C

THREEWALL_850 50 0.30 1.14 4.2 52.582 BASE_311 TRUE Temperature < 130 CTHREEWALL_850 50 0.30 1.14 4.5 47.396 BASE_311 TRUE Temperature < 130 CTHREEWALL_850 50 0.30 1.14 4.8 43.576 BASE_311 TRUE Temperature < 130 CTHREEWALL_850 50 0.30 1.14 5.1 42.094 BASE_311 TRUE Temperature < 130 CTHREEWALL_851 100 0.30 1.14 2.4 275.53 BASE_312 FALSE Not FilteredTHREEWALL_851 100 0.30 1.14 2.7 159.25 BASE_312 FALSE Not FilteredTHREEWALL_851 100 0.30 1.14 3 127.63 BASE_312 TRUE Temperature < 130 CTHREEWALL_851 100 0.30 1.14 3.3 105.49 BASE_312 TRUE Temperature < 130 CTHREEWALL_851 100 0.30 1.14 3.6 91.185 BASE_312 TRUE Temperature < 130 CTHREEWALL_851 100 0.30 1.14 3.9 80.914 BASE_312 TRUE Temperature < 130 CTHREEWALL_851 100 0.30 1.14 4.2 74.131 BASE_312 TRUE Temperature < 130 CTHREEWALL_851 100 0.30 1.14 4.5 66.294 BASE_312 TRUE Temperature < 130 CTHREEWALL_851 100 0.30 1.14 4.8 61.449 BASE_312 TRUE Temperature < 130 CTHREEWALL_851 100 0.30 1.14 5.1 57.622 BASE_312 TRUE Temperature < 130 CTHREEWALL_851 100 0.30 1.14 5.4 53.854 BASE_312 TRUE Temperature < 130 CTHREEWALL_851 100 0.30 1.14 5.7 49.889 BASE_312 TRUE Temperature < 130 CTHREEWALL_851 100 0.30 1.14 6 47.38 BASE_312 TRUE Temperature < 130 CTHREEWALL_857 50 0.30 1.98 2.4 435.6 BASE_322 FALSE Not FilteredTHREEWALL_857 50 0.30 1.98 2.7 255.48 BASE_322 FALSE Not FilteredTHREEWALL_857 50 0.30 1.98 3 177.34 BASE_322 FALSE Not Filtered

E-61 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

THREEWALL_857 50 0.30 1.98 3.3 131.29 BASE_322 FALSE Not Filtered

THREEWALL_857 50 0.30 1.98 3.6 103.33 BASE_322 TRUE Temperature < 130 CTHREEWALL_857 50 0.30 1.98 3.9 86.596 BASE_322 TRUE Temperature < 130 CTHREEWALL_857 50 0.30 1.98 4.2 75.4 BASE_322 TRUE Temperature < 130 CTHREEWALL_857 50 0.30 1.98 4.5 64.238 BASE_322 TRUE Temperature < 130 CTHREEWALL_857 50 0.30 1.98 4.8 57.548 BASE_322 TRUE Temperature < 130 CTHREEWALL_857 50 0.30 1.98 5.1 52.801 BASE_322 TRUE Temperature < 130 CTHREEWALL_857 50 0.30 1.98 5.4 49.598 BASE_322 TRUE Temperature < 130 CTHREEWALL_857 50 0.30 1.98 5.7 45.826 BASE_322 TRUE Temperature < 130 CTHREEWALL_857 50 0.30 1.98 6 43.713 BASE_322 TRUE Temperature < 130 CTHREEWALL_858 100 0.30 1.98 2.4 820.14 BASE_323 TRUE Temperature > 800 CTHREEWALL_858 100 0.30 1.98 2.7 530.25 BASE_323 FALSE Not FilteredTHREEWALL_858 100 0.30 1.98 3 347.37 BASE_323 FALSE Not FilteredTHREEWALL_858 100 0.30 1.98 3.3 238.83 BASE_323 FALSE Not FilteredTHREEWALL_858 100 0.30 1.98 3.6 189.87 BASE_323 FALSE Not FilteredTHREEWALL_858 100 0.30 1.98 3.9 155.33 BASE_323 FALSE Not FilteredTHREEWALL_858 100 0.30 1.98 4.2 129.01 BASE_323 TRUE Temperature < 130 CTHREEWALL_858 100 0.30 1.98 4.5 106.66 BASE_323 TRUE Temperature < 130 CTHREEWALL_858 100 0.30 1.98 4.8 92.817 BASE_323 TRUE Temperature < 130 CTHREEWALL_858 100 0.30 1.98 5.1 82.359 BASE_323 TRUE Temperature < 130 CTHREEWALL_858 100 0.30 1.98 5.4 72.31 BASE_323 TRUE Temperature < 130 C

E-62 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

THREEWALL_858 100 0.30 1.98 5.7 65.47 BASE_323 TRUE Temperature < 130 C

THREEWALL_858 100 0.30 1.98 6 59.874 BASE_323 TRUE Temperature < 130 CTHREEWALL_908 200 0.61 0.30 2.4 209.07 BASE_302 TRUE Source Located 1 ft. above GroundTHREEWALL_908 200 0.61 0.30 2.7 138.48 BASE_302 TRUE Source Located 1 ft. above GroundTHREEWALL_908 200 0.61 0.30 3 110.24 BASE_302 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_908 200 0.61 0.30 3.3 92.241 BASE_302 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_908 200 0.61 0.30 3.6 86.418 BASE_302 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_908 200 0.61 0.30 3.9 79.258 BASE_302 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_908 200 0.61 0.30 4.2 72.942 BASE_302 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_908 200 0.61 0.30 4.5 68.566 BASE_302 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_908 200 0.61 0.30 4.8 64.97 BASE_302 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_908 200 0.61 0.30 5.1 61.531 BASE_302 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_908 200 0.61 0.30 5.4 57.966 BASE_302 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_908 200 0.61 0.30 5.7 55.271 BASE_302 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_908 200 0.61 0.30 6 53.819 BASE_302 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

E-63 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

THREEWALL_909 300 0.61 0.30 2.4 294.83 BASE_303 TRUE Source Located 1 ft. above Ground

THREEWALL_909 300 0.61 0.30 2.7 191.52 BASE_303 TRUE Source Located 1 ft. above GroundTHREEWALL_909 300 0.61 0.30 3 149.7 BASE_303 TRUE Source Located 1 ft. above GroundTHREEWALL_909 300 0.61 0.30 3.3 122.65 BASE_303 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_909 300 0.61 0.30 3.6 109.56 BASE_303 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_909 300 0.61 0.30 3.9 100.78 BASE_303 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_909 300 0.61 0.30 4.2 93.85 BASE_303 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_909 300 0.61 0.30 4.5 84.794 BASE_303 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_909 300 0.61 0.30 4.8 78.946 BASE_303 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_909 300 0.61 0.30 5.1 73.842 BASE_303 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_909 300 0.61 0.30 5.4 69.304 BASE_303 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_909 300 0.61 0.30 5.7 66.545 BASE_303 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_909 300 0.61 0.30 6 63.528 BASE_303 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_910 400 0.61 0.30 2.4 383.52 BASE_304 TRUE Source Located 1 ft. above GroundTHREEWALL_910 400 0.61 0.30 2.7 228.97 BASE_304 TRUE Source Located 1 ft. above Ground

E-64 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

THREEWALL_910 400 0.61 0.30 3 183.34 BASE_304 TRUE Source Located 1 ft. above Ground

THREEWALL_910 400 0.61 0.30 3.3 151.37 BASE_304 TRUE Source Located 1 ft. above GroundTHREEWALL_910 400 0.61 0.30 3.6 133.13 BASE_304 TRUE Source Located 1 ft. above GroundTHREEWALL_910 400 0.61 0.30 3.9 117.64 BASE_304 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_910 400 0.61 0.30 4.2 104.51 BASE_304 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_910 400 0.61 0.30 4.5 94.862 BASE_304 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_910 400 0.61 0.30 4.8 88.761 BASE_304 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_910 400 0.61 0.30 5.1 84.237 BASE_304 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_910 400 0.61 0.30 5.4 78.224 BASE_304 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_910 400 0.61 0.30 5.7 72.443 BASE_304 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_910 400 0.61 0.30 6 68.486 BASE_304 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_911 500 0.61 0.30 2.4 540.81 BASE_305 TRUE Source Located 1 ft. above GroundTHREEWALL_911 500 0.61 0.30 2.7 328 BASE_305 TRUE Source Located 1 ft. above GroundTHREEWALL_911 500 0.61 0.30 3 244.14 BASE_305 TRUE Source Located 1 ft. above GroundTHREEWALL_911 500 0.61 0.30 3.3 192.58 BASE_305 TRUE Source Located 1 ft. above GroundTHREEWALL_911 500 0.61 0.30 3.6 164.65 BASE_305 TRUE Source Located 1 ft. above Ground

E-65 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

THREEWALL_911 500 0.61 0.30 3.9 141.73 BASE_305 TRUE Source Located 1 ft. above Ground

THREEWALL_911 500 0.61 0.30 4.2 127.64 BASE_305 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_911 500 0.61 0.30 4.5 114.66 BASE_305 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_911 500 0.61 0.30 4.8 105.09 BASE_305 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_911 500 0.61 0.30 5.1 98.004 BASE_305 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_911 500 0.61 0.30 5.4 90.971 BASE_305 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_911 500 0.61 0.30 5.7 83.486 BASE_305 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_911 500 0.61 0.30 6 78.099 BASE_305 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_912 600 0.61 0.30 2.4 627.21 BASE_306 TRUE Source Located 1 ft. above GroundTHREEWALL_912 600 0.61 0.30 2.7 383.78 BASE_306 TRUE Source Located 1 ft. above GroundTHREEWALL_912 600 0.61 0.30 3 277.38 BASE_306 TRUE Source Located 1 ft. above GroundTHREEWALL_912 600 0.61 0.30 3.3 220.14 BASE_306 TRUE Source Located 1 ft. above GroundTHREEWALL_912 600 0.61 0.30 3.6 186.98 BASE_306 TRUE Source Located 1 ft. above GroundTHREEWALL_912 600 0.61 0.30 3.9 160.79 BASE_306 TRUE Source Located 1 ft. above GroundTHREEWALL_912 600 0.61 0.30 4.2 139.96 BASE_306 TRUE Source Located 1 ft. above GroundTHREEWALL_912 600 0.61 0.30 4.5 120.03 BASE_306 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

E-66 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

THREEWALL_912 600 0.61 0.30 4.8 108.42 BASE_306 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_912 600 0.61 0.30 5.1 99.334 BASE_306 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_912 600 0.61 0.30 5.4 91.383 BASE_306 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_912 600 0.61 0.30 5.7 84.312 BASE_306 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_912 600 0.61 0.30 6 81.252 BASE_306 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_915 200 0.61 1.14 2.4 320.06 BASE_313 FALSE Not FilteredTHREEWALL_915 200 0.61 1.14 2.7 179.86 BASE_313 FALSE Not FilteredTHREEWALL_915 200 0.61 1.14 3 154.36 BASE_313 FALSE Not FilteredTHREEWALL_915 200 0.61 1.14 3.3 128.98 BASE_313 TRUE Temperature < 130 CTHREEWALL_915 200 0.61 1.14 3.6 113.2 BASE_313 TRUE Temperature < 130 CTHREEWALL_915 200 0.61 1.14 3.9 106.12 BASE_313 TRUE Temperature < 130 CTHREEWALL_915 200 0.61 1.14 4.2 94.481 BASE_313 TRUE Temperature < 130 CTHREEWALL_915 200 0.61 1.14 4.5 87.577 BASE_313 TRUE Temperature < 130 CTHREEWALL_915 200 0.61 1.14 4.8 85.132 BASE_313 TRUE Temperature < 130 CTHREEWALL_915 200 0.61 1.14 5.1 71.536 BASE_313 TRUE Temperature < 130 CTHREEWALL_915 200 0.61 1.14 5.4 66.804 BASE_313 TRUE Temperature < 130 CTHREEWALL_915 200 0.61 1.14 5.7 62.677 BASE_313 TRUE Temperature < 130 CTHREEWALL_915 200 0.61 1.14 6 58.233 BASE_313 TRUE Temperature < 130 C

E-67 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

THREEWALL_916 300 0.61 1.14 2.4 508.54 BASE_314 FALSE Not Filtered

THREEWALL_916 300 0.61 1.14 2.7 270.02 BASE_314 FALSE Not FilteredTHREEWALL_916 300 0.61 1.14 3 194.28 BASE_314 FALSE Not FilteredTHREEWALL_916 300 0.61 1.14 3.3 161.38 BASE_314 FALSE Not FilteredTHREEWALL_916 300 0.61 1.14 3.6 143.99 BASE_314 FALSE Not FilteredTHREEWALL_916 300 0.61 1.14 3.9 130.29 BASE_314 FALSE Not FilteredTHREEWALL_916 300 0.61 1.14 4.2 116.98 BASE_314 TRUE Temperature < 130 CTHREEWALL_916 300 0.61 1.14 4.5 103.62 BASE_314 TRUE Temperature < 130 CTHREEWALL_916 300 0.61 1.14 4.8 93.72 BASE_314 TRUE Temperature < 130 CTHREEWALL_916 300 0.61 1.14 5.1 85.707 BASE_314 TRUE Temperature < 130 CTHREEWALL_916 300 0.61 1.14 5.4 77.268 BASE_314 TRUE Temperature < 130 CTHREEWALL_916 300 0.61 1.14 5.7 69.468 BASE_314 TRUE Temperature < 130 CTHREEWALL_916 300 0.61 1.14 6 66.588 BASE_314 TRUE Temperature < 130 CTHREEWALL_917 400 0.61 1.14 2.4 683.59 BASE_315 FALSE Not FilteredTHREEWALL_917 400 0.61 1.14 2.7 390.31 BASE_315 FALSE Not FilteredTHREEWALL_917 400 0.61 1.14 3 270.68 BASE_315 FALSE Not FilteredTHREEWALL_917 400 0.61 1.14 3.3 203.21 BASE_315 FALSE Not FilteredTHREEWALL_917 400 0.61 1.14 3.6 172.33 BASE_315 FALSE Not FilteredTHREEWALL_917 400 0.61 1.14 3.9 152.92 BASE_315 FALSE Not FilteredTHREEWALL_917 400 0.61 1.14 4.2 138.8 BASE_315 FALSE Not FilteredTHREEWALL_917 400 0.61 1.14 4.5 121.89 BASE_315 TRUE Temperature < 130 C

E-68 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

THREEWALL_917 400 0.61 1.14 4.8 110.66 BASE_315 TRUE Temperature < 130 C

THREEWALL_917 400 0.61 1.14 5.1 101.05 BASE_315 TRUE Temperature < 130 CTHREEWALL_917 400 0.61 1.14 5.4 91.643 BASE_315 TRUE Temperature < 130 CTHREEWALL_917 400 0.61 1.14 5.7 84.816 BASE_315 TRUE Temperature < 130 CTHREEWALL_917 400 0.61 1.14 6 80.483 BASE_315 TRUE Temperature < 130 CTHREEWALL_918 500 0.61 1.14 2.4 826.87 BASE_316 TRUE Temperature > 800 CTHREEWALL_918 500 0.61 1.14 2.7 486.61 BASE_316 FALSE Not FilteredTHREEWALL_918 500 0.61 1.14 3 333.59 BASE_316 FALSE Not FilteredTHREEWALL_918 500 0.61 1.14 3.3 242.06 BASE_316 FALSE Not FilteredTHREEWALL_918 500 0.61 1.14 3.6 204.52 BASE_316 FALSE Not FilteredTHREEWALL_918 500 0.61 1.14 3.9 175.58 BASE_316 FALSE Not FilteredTHREEWALL_918 500 0.61 1.14 4.2 154.38 BASE_316 FALSE Not FilteredTHREEWALL_918 500 0.61 1.14 4.5 130.96 BASE_316 FALSE Not FilteredTHREEWALL_918 500 0.61 1.14 4.8 118.68 BASE_316 TRUE Temperature < 130 CTHREEWALL_918 500 0.61 1.14 5.1 108.22 BASE_316 TRUE Temperature < 130 CTHREEWALL_918 500 0.61 1.14 5.4 99.367 BASE_316 TRUE Temperature < 130 CTHREEWALL_918 500 0.61 1.14 5.7 89.439 BASE_316 TRUE Temperature < 130 CTHREEWALL_918 500 0.61 1.14 6 83.231 BASE_316 TRUE Temperature < 130 CTHREEWALL_919 600 0.61 1.14 2.4 846.23 BASE_317 TRUE Temperature > 800 CTHREEWALL_919 600 0.61 1.14 2.7 582.28 BASE_317 FALSE Not FilteredTHREEWALL_919 600 0.61 1.14 3 436.03 BASE_317 FALSE Not Filtered

E-69 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

THREEWALL_919 600 0.61 1.14 3.3 325.81 BASE_317 FALSE Not Filtered

THREEWALL_919 600 0.61 1.14 3.6 268 BASE_317 FALSE Not FilteredTHREEWALL_919 600 0.61 1.14 3.9 223.92 BASE_317 FALSE Not FilteredTHREEWALL_919 600 0.61 1.14 4.2 196.1 BASE_317 FALSE Not FilteredTHREEWALL_919 600 0.61 1.14 4.5 172.14 BASE_317 FALSE Not FilteredTHREEWALL_919 600 0.61 1.14 4.8 158.53 BASE_317 FALSE Not FilteredTHREEWALL_919 600 0.61 1.14 5.1 143.64 BASE_317 FALSE Not FilteredTHREEWALL_919 600 0.61 1.14 5.4 129.78 BASE_317 TRUE Temperature < 130 CTHREEWALL_919 600 0.61 1.14 5.7 118.04 BASE_317 TRUE Temperature < 130 CTHREEWALL_919 600 0.61 1.14 6 110.28 BASE_317 TRUE Temperature < 130 CTHREEWALL_922 200 0.61 1.98 2.4 894.59 BASE_324 TRUE Temperature > 800 CTHREEWALL_922 200 0.61 1.98 2.7 607.45 BASE_324 FALSE Not FilteredTHREEWALL_922 200 0.61 1.98 3 438.25 BASE_324 FALSE Not FilteredTHREEWALL_922 200 0.61 1.98 3.3 329.14 BASE_324 FALSE Not FilteredTHREEWALL_922 200 0.61 1.98 3.6 256.87 BASE_324 FALSE Not FilteredTHREEWALL_922 200 0.61 1.98 3.9 203.85 BASE_324 FALSE Not FilteredTHREEWALL_922 200 0.61 1.98 4.2 168.83 BASE_324 FALSE Not FilteredTHREEWALL_922 200 0.61 1.98 4.5 145.65 BASE_324 FALSE Not FilteredTHREEWALL_922 200 0.61 1.98 4.8 129.93 BASE_324 TRUE Temperature < 130 CTHREEWALL_922 200 0.61 1.98 5.1 115.64 BASE_324 TRUE Temperature < 130 CTHREEWALL_922 200 0.61 1.98 5.4 103.08 BASE_324 TRUE Temperature < 130 C

E-70 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

THREEWALL_922 200 0.61 1.98 5.7 91.731 BASE_324 TRUE Temperature < 130 C

THREEWALL_922 200 0.61 1.98 6 84.103 BASE_324 TRUE Temperature < 130 CTHREEWALL_923 300 0.61 1.98 2.4 983.87 BASE_325 TRUE Temperature > 800 CTHREEWALL_923 300 0.61 1.98 2.7 922.29 BASE_325 TRUE Temperature > 800 CTHREEWALL_923 300 0.61 1.98 3 726.09 BASE_325 FALSE Not FilteredTHREEWALL_923 300 0.61 1.98 3.3 510.62 BASE_325 FALSE Not FilteredTHREEWALL_923 300 0.61 1.98 3.6 388.3 BASE_325 FALSE Not FilteredTHREEWALL_923 300 0.61 1.98 3.9 290.83 BASE_325 FALSE Not FilteredTHREEWALL_923 300 0.61 1.98 4.2 230.29 BASE_325 FALSE Not FilteredTHREEWALL_923 300 0.61 1.98 4.5 182.55 BASE_325 FALSE Not FilteredTHREEWALL_923 300 0.61 1.98 4.8 157.83 BASE_325 FALSE Not FilteredTHREEWALL_923 300 0.61 1.98 5.1 140.83 BASE_325 FALSE Not FilteredTHREEWALL_923 300 0.61 1.98 5.4 122.74 BASE_325 TRUE Temperature < 130 CTHREEWALL_923 300 0.61 1.98 5.7 110.35 BASE_325 TRUE Temperature < 130 CTHREEWALL_923 300 0.61 1.98 6 101.38 BASE_325 TRUE Temperature < 130 CTHREEWALL_924 400 0.61 1.98 2.4 1014.1 BASE_326 TRUE Temperature > 800 CTHREEWALL_924 400 0.61 1.98 2.7 978.89 BASE_326 TRUE Temperature > 800 CTHREEWALL_924 400 0.61 1.98 3 883.71 BASE_326 TRUE Temperature > 800 CTHREEWALL_924 400 0.61 1.98 3.3 681.79 BASE_326 FALSE Not FilteredTHREEWALL_924 400 0.61 1.98 3.6 519.42 BASE_326 FALSE Not FilteredTHREEWALL_924 400 0.61 1.98 3.9 388.24 BASE_326 FALSE Not Filtered

E-71 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

THREEWALL_924 400 0.61 1.98 4.2 306.26 BASE_326 FALSE Not Filtered

THREEWALL_924 400 0.61 1.98 4.5 246.33 BASE_326 FALSE Not FilteredTHREEWALL_924 400 0.61 1.98 4.8 213.8 BASE_326 FALSE Not FilteredTHREEWALL_924 400 0.61 1.98 5.1 183.16 BASE_326 FALSE Not FilteredTHREEWALL_924 400 0.61 1.98 5.4 157.27 BASE_326 FALSE Not FilteredTHREEWALL_924 400 0.61 1.98 5.7 137.47 BASE_326 FALSE Not FilteredTHREEWALL_924 400 0.61 1.98 6 126.19 BASE_326 TRUE Temperature < 130 CTHREEWALL_925 500 0.61 1.98 2.4 1106.3 BASE_327 TRUE Temperature > 800 CTHREEWALL_925 500 0.61 1.98 2.7 1011.3 BASE_327 TRUE Temperature > 800 CTHREEWALL_925 500 0.61 1.98 3 928.71 BASE_327 TRUE Temperature > 800 CTHREEWALL_925 500 0.61 1.98 3.3 799.73 BASE_327 FALSE Not FilteredTHREEWALL_925 500 0.61 1.98 3.6 664.76 BASE_327 FALSE Not FilteredTHREEWALL_925 500 0.61 1.98 3.9 518.6 BASE_327 FALSE Not FilteredTHREEWALL_925 500 0.61 1.98 4.2 405.1 BASE_327 FALSE Not FilteredTHREEWALL_925 500 0.61 1.98 4.5 310.44 BASE_327 FALSE Not FilteredTHREEWALL_925 500 0.61 1.98 4.8 262.34 BASE_327 FALSE Not FilteredTHREEWALL_925 500 0.61 1.98 5.1 221.57 BASE_327 FALSE Not FilteredTHREEWALL_925 500 0.61 1.98 5.4 192.52 BASE_327 FALSE Not FilteredTHREEWALL_925 500 0.61 1.98 5.7 166.57 BASE_327 FALSE Not FilteredTHREEWALL_925 500 0.61 1.98 6 146.18 BASE_327 FALSE Not FilteredTHREEWALL_926 600 0.61 1.98 2.4 1089.8 BASE_328 TRUE Temperature > 800 C

E-72 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

THREEWALL_926 600 0.61 1.98 2.7 1070.9 BASE_328 TRUE Temperature > 800 C

THREEWALL_926 600 0.61 1.98 3 984.08 BASE_328 TRUE Temperature > 800 CTHREEWALL_926 600 0.61 1.98 3.3 844.18 BASE_328 TRUE Temperature > 800 CTHREEWALL_926 600 0.61 1.98 3.6 706.97 BASE_328 FALSE Not FilteredTHREEWALL_926 600 0.61 1.98 3.9 561.53 BASE_328 FALSE Not FilteredTHREEWALL_926 600 0.61 1.98 4.2 440.71 BASE_328 FALSE Not FilteredTHREEWALL_926 600 0.61 1.98 4.5 340.56 BASE_328 FALSE Not FilteredTHREEWALL_926 600 0.61 1.98 4.8 284.69 BASE_328 FALSE Not FilteredTHREEWALL_926 600 0.61 1.98 5.1 244.92 BASE_328 FALSE Not FilteredTHREEWALL_926 600 0.61 1.98 5.4 208.27 BASE_328 FALSE Not FilteredTHREEWALL_926 600 0.61 1.98 5.7 183.19 BASE_328 FALSE Not FilteredTHREEWALL_926 600 0.61 1.98 6 166.48 BASE_328 FALSE Not FilteredTHREEWALL_972 300 0.91 0.30 2.4 184.56 BASE_307 TRUE Source Located 1 ft. above GroundTHREEWALL_972 300 0.91 0.30 2.7 118.56 BASE_307 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_972 300 0.91 0.30 3 97.066 BASE_307 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_972 300 0.91 0.30 3.3 83.193 BASE_307 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_972 300 0.91 0.30 3.6 76.028 BASE_307 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_972 300 0.91 0.30 3.9 70.479 BASE_307 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

E-73 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

THREEWALL_972 300 0.91 0.30 4.2 66.231 BASE_307 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_972 300 0.91 0.30 4.5 64.326 BASE_307 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_972 300 0.91 0.30 4.8 62.587 BASE_307 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_972 300 0.91 0.30 5.1 60.063 BASE_307 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_972 300 0.91 0.30 5.4 56.428 BASE_307 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_972 300 0.91 0.30 5.7 52.662 BASE_307 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_972 300 0.91 0.30 6 50.738 BASE_307 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_973 400 0.91 0.30 2.4 240.59 BASE_308 TRUE Source Located 1 ft. above GroundTHREEWALL_973 400 0.91 0.30 2.7 144.47 BASE_308 TRUE Source Located 1 ft. above GroundTHREEWALL_973 400 0.91 0.30 3 115.08 BASE_308 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_973 400 0.91 0.30 3.3 102.6 BASE_308 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_973 400 0.91 0.30 3.6 92.14 BASE_308 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_973 400 0.91 0.30 3.9 82.221 BASE_308 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_973 400 0.91 0.30 4.2 76.611 BASE_308 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

E-74 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

THREEWALL_973 400 0.91 0.30 4.5 72.131 BASE_308 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_973 400 0.91 0.30 4.8 69.414 BASE_308 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_973 400 0.91 0.30 5.1 66.911 BASE_308 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_973 400 0.91 0.30 5.4 63.254 BASE_308 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_973 400 0.91 0.30 5.7 58.782 BASE_308 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_973 400 0.91 0.30 6 56.053 BASE_308 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_974 500 0.91 0.30 2.4 303.21 BASE_309 TRUE Source Located 1 ft. above GroundTHREEWALL_974 500 0.91 0.30 2.7 185.97 BASE_309 TRUE Source Located 1 ft. above GroundTHREEWALL_974 500 0.91 0.30 3 144.03 BASE_309 TRUE Source Located 1 ft. above GroundTHREEWALL_974 500 0.91 0.30 3.3 120.84 BASE_309 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_974 500 0.91 0.30 3.6 110.2 BASE_309 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_974 500 0.91 0.30 3.9 101.09 BASE_309 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_974 500 0.91 0.30 4.2 92.989 BASE_309 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_974 500 0.91 0.30 4.5 85.945 BASE_309 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_974 500 0.91 0.30 4.8 82.585 BASE_309 TRUE Temperature < 130 C , Source

E-75 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

Located 1 ft. above Ground

THREEWALL_974 500 0.91 0.30 5.1 78.139 BASE_309 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_974 500 0.91 0.30 5.4 72.292 BASE_309 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_974 500 0.91 0.30 5.7 65.906 BASE_309 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_974 500 0.91 0.30 6 61.784 BASE_309 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_975 600 0.91 0.30 2.4 351.27 BASE_310 TRUE Source Located 1 ft. above GroundTHREEWALL_975 600 0.91 0.30 2.7 208.86 BASE_310 TRUE Source Located 1 ft. above GroundTHREEWALL_975 600 0.91 0.30 3 165.74 BASE_310 TRUE Source Located 1 ft. above GroundTHREEWALL_975 600 0.91 0.30 3.3 142 BASE_310 TRUE Source Located 1 ft. above GroundTHREEWALL_975 600 0.91 0.30 3.6 128.21 BASE_310 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_975 600 0.91 0.30 3.9 116.86 BASE_310 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_975 600 0.91 0.30 4.2 106 BASE_310 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_975 600 0.91 0.30 4.5 95.935 BASE_310 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_975 600 0.91 0.30 4.8 89.561 BASE_310 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_975 600 0.91 0.30 5.1 85.5 BASE_310 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

E-76 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

THREEWALL_975 600 0.91 0.30 5.4 81.763 BASE_310 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_975 600 0.91 0.30 5.7 77.857 BASE_310 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_975 600 0.91 0.30 6 74.923 BASE_310 TRUE

Temperature < 130 C , Source

Located 1 ft. above Ground

THREEWALL_979 300 0.91 1.14 2.4 310.52 BASE_318 FALSE Not FilteredTHREEWALL_979 300 0.91 1.14 2.7 184.64 BASE_318 FALSE Not FilteredTHREEWALL_979 300 0.91 1.14 3 146.48 BASE_318 FALSE Not FilteredTHREEWALL_979 300 0.91 1.14 3.3 124.98 BASE_318 TRUE Temperature < 130 CTHREEWALL_979 300 0.91 1.14 3.6 112.59 BASE_318 TRUE Temperature < 130 CTHREEWALL_979 300 0.91 1.14 3.9 100.44 BASE_318 TRUE Temperature < 130 CTHREEWALL_979 300 0.91 1.14 4.2 91.793 BASE_318 TRUE Temperature < 130 CTHREEWALL_979 300 0.91 1.14 4.5 84.386 BASE_318 TRUE Temperature < 130 CTHREEWALL_979 300 0.91 1.14 4.8 78.823 BASE_318 TRUE Temperature < 130 CTHREEWALL_979 300 0.91 1.14 5.1 74.82 BASE_318 TRUE Temperature < 130 CTHREEWALL_979 300 0.91 1.14 5.4 69.589 BASE_318 TRUE Temperature < 130 CTHREEWALL_979 300 0.91 1.14 5.7 65.922 BASE_318 TRUE Temperature < 130 CTHREEWALL_979 300 0.91 1.14 6 63.23 BASE_318 TRUE Temperature < 130 CTHREEWALL_980 400 0.91 1.14 2.4 380.97 BASE_319 FALSE Not FilteredTHREEWALL_980 400 0.91 1.14 2.7 231.62 BASE_319 FALSE Not FilteredTHREEWALL_980 400 0.91 1.14 3 184.42 BASE_319 FALSE Not Filtered

E-77 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

THREEWALL_980 400 0.91 1.14 3.3 151.59 BASE_319 FALSE Not Filtered

THREEWALL_980 400 0.91 1.14 3.6 134.53 BASE_319 FALSE Not FilteredTHREEWALL_980 400 0.91 1.14 3.9 121.09 BASE_319 TRUE Temperature < 130 CTHREEWALL_980 400 0.91 1.14 4.2 111.18 BASE_319 TRUE Temperature < 130 CTHREEWALL_980 400 0.91 1.14 4.5 103.03 BASE_319 TRUE Temperature < 130 CTHREEWALL_980 400 0.91 1.14 4.8 97.236 BASE_319 TRUE Temperature < 130 CTHREEWALL_980 400 0.91 1.14 5.1 91.365 BASE_319 TRUE Temperature < 130 CTHREEWALL_980 400 0.91 1.14 5.4 84.422 BASE_319 TRUE Temperature < 130 CTHREEWALL_980 400 0.91 1.14 5.7 79.351 BASE_319 TRUE Temperature < 130 CTHREEWALL_980 400 0.91 1.14 6 75.216 BASE_319 TRUE Temperature < 130 CTHREEWALL_981 500 0.91 1.14 2.4 522.3 BASE_320 FALSE Not FilteredTHREEWALL_981 500 0.91 1.14 2.7 283.14 BASE_320 FALSE Not FilteredTHREEWALL_981 500 0.91 1.14 3 223.96 BASE_320 FALSE Not FilteredTHREEWALL_981 500 0.91 1.14 3.3 187.48 BASE_320 FALSE Not FilteredTHREEWALL_981 500 0.91 1.14 3.6 163.06 BASE_320 FALSE Not FilteredTHREEWALL_981 500 0.91 1.14 3.9 146.31 BASE_320 FALSE Not FilteredTHREEWALL_981 500 0.91 1.14 4.2 133.8 BASE_320 FALSE Not FilteredTHREEWALL_981 500 0.91 1.14 4.5 122.56 BASE_320 TRUE Temperature < 130 CTHREEWALL_981 500 0.91 1.14 4.8 112.15 BASE_320 TRUE Temperature < 130 CTHREEWALL_981 500 0.91 1.14 5.1 104.23 BASE_320 TRUE Temperature < 130 CTHREEWALL_981 500 0.91 1.14 5.4 96.185 BASE_320 TRUE Temperature < 130 C

E-78 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

THREEWALL_981 500 0.91 1.14 5.7 90.141 BASE_320 TRUE Temperature < 130 C

THREEWALL_981 500 0.91 1.14 6 84.866 BASE_320 TRUE Temperature < 130 CTHREEWALL_982 600 0.91 1.14 2.4 604.51 BASE_321 FALSE Not FilteredTHREEWALL_982 600 0.91 1.14 2.7 350.93 BASE_321 FALSE Not FilteredTHREEWALL_982 600 0.91 1.14 3 268.81 BASE_321 FALSE Not FilteredTHREEWALL_982 600 0.91 1.14 3.3 221.1 BASE_321 FALSE Not FilteredTHREEWALL_982 600 0.91 1.14 3.6 193.38 BASE_321 FALSE Not FilteredTHREEWALL_982 600 0.91 1.14 3.9 171.54 BASE_321 FALSE Not FilteredTHREEWALL_982 600 0.91 1.14 4.2 153.52 BASE_321 FALSE Not FilteredTHREEWALL_982 600 0.91 1.14 4.5 138.27 BASE_321 FALSE Not FilteredTHREEWALL_982 600 0.91 1.14 4.8 126.36 BASE_321 TRUE Temperature < 130 CTHREEWALL_982 600 0.91 1.14 5.1 116.64 BASE_321 TRUE Temperature < 130 CTHREEWALL_982 600 0.91 1.14 5.4 108.26 BASE_321 TRUE Temperature < 130 CTHREEWALL_982 600 0.91 1.14 5.7 100.09 BASE_321 TRUE Temperature < 130 CTHREEWALL_982 600 0.91 1.14 6 94.122 BASE_321 TRUE Temperature < 130 CTHREEWALL_986 300 0.91 1.98 2.4 844.4 BASE_329 TRUE Temperature > 800 CTHREEWALL_986 300 0.91 1.98 2.7 681.25 BASE_329 FALSE Not FilteredTHREEWALL_986 300 0.91 1.98 3 490.11 BASE_329 FALSE Not FilteredTHREEWALL_986 300 0.91 1.98 3.3 353.3 BASE_329 FALSE Not FilteredTHREEWALL_986 300 0.91 1.98 3.6 278.73 BASE_329 FALSE Not FilteredTHREEWALL_986 300 0.91 1.98 3.9 227.21 BASE_329 FALSE Not Filtered

E-79 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

THREEWALL_986 300 0.91 1.98 4.2 182.1 BASE_329 FALSE Not Filtered

THREEWALL_986 300 0.91 1.98 4.5 148.46 BASE_329 FALSE Not FilteredTHREEWALL_986 300 0.91 1.98 4.8 126.79 BASE_329 TRUE Temperature < 130 CTHREEWALL_986 300 0.91 1.98 5.1 112.9 BASE_329 TRUE Temperature < 130 CTHREEWALL_986 300 0.91 1.98 5.4 99.758 BASE_329 TRUE Temperature < 130 CTHREEWALL_986 300 0.91 1.98 5.7 88.638 BASE_329 TRUE Temperature < 130 CTHREEWALL_986 300 0.91 1.98 6 81.318 BASE_329 TRUE Temperature < 130 CTHREEWALL_987 400 0.91 1.98 2.4 909.89 BASE_330 TRUE Temperature > 800 CTHREEWALL_987 400 0.91 1.98 2.7 857.59 BASE_330 TRUE Temperature > 800 CTHREEWALL_987 400 0.91 1.98 3 676.43 BASE_330 FALSE Not FilteredTHREEWALL_987 400 0.91 1.98 3.3 441.27 BASE_330 FALSE Not FilteredTHREEWALL_987 400 0.91 1.98 3.6 339.87 BASE_330 FALSE Not FilteredTHREEWALL_987 400 0.91 1.98 3.9 266.42 BASE_330 FALSE Not FilteredTHREEWALL_987 400 0.91 1.98 4.2 220.39 BASE_330 FALSE Not FilteredTHREEWALL_987 400 0.91 1.98 4.5 182.32 BASE_330 FALSE Not FilteredTHREEWALL_987 400 0.91 1.98 4.8 164.19 BASE_330 FALSE Not FilteredTHREEWALL_987 400 0.91 1.98 5.1 148.53 BASE_330 FALSE Not FilteredTHREEWALL_987 400 0.91 1.98 5.4 135.35 BASE_330 FALSE Not FilteredTHREEWALL_987 400 0.91 1.98 5.7 121.94 BASE_330 TRUE Temperature < 130 CTHREEWALL_987 400 0.91 1.98 6 113.94 BASE_330 TRUE Temperature < 130 CTHREEWALL_988 500 0.91 1.98 2.4 973.68 BASE_331 TRUE Temperature > 800 C

E-80 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

THREEWALL_988 500 0.91 1.98 2.7 891.03 BASE_331 TRUE Temperature > 800 C

THREEWALL_988 500 0.91 1.98 3 799.43 BASE_331 FALSE Not FilteredTHREEWALL_988 500 0.91 1.98 3.3 606.92 BASE_331 FALSE Not FilteredTHREEWALL_988 500 0.91 1.98 3.6 454.55 BASE_331 FALSE Not FilteredTHREEWALL_988 500 0.91 1.98 3.9 343.91 BASE_331 FALSE Not FilteredTHREEWALL_988 500 0.91 1.98 4.2 282.91 BASE_331 FALSE Not FilteredTHREEWALL_988 500 0.91 1.98 4.5 229.44 BASE_331 FALSE Not FilteredTHREEWALL_988 500 0.91 1.98 4.8 198.62 BASE_331 FALSE Not FilteredTHREEWALL_988 500 0.91 1.98 5.1 177.02 BASE_331 FALSE Not FilteredTHREEWALL_988 500 0.91 1.98 5.4 157.24 BASE_331 FALSE Not FilteredTHREEWALL_988 500 0.91 1.98 5.7 137.4 BASE_331 FALSE Not FilteredTHREEWALL_988 500 0.91 1.98 6 125.87 BASE_331 TRUE Temperature < 130 CTHREEWALL_989 600 0.91 1.98 2.4 1027.7 BASE_332 TRUE Temperature > 800 CTHREEWALL_989 600 0.91 1.98 2.7 965.5 BASE_332 TRUE Temperature > 800 CTHREEWALL_989 600 0.91 1.98 3 918.36 BASE_332 TRUE Temperature > 800 CTHREEWALL_989 600 0.91 1.98 3.3 752.38 BASE_332 FALSE Not FilteredTHREEWALL_989 600 0.91 1.98 3.6 582.49 BASE_332 FALSE Not FilteredTHREEWALL_989 600 0.91 1.98 3.9 431.65 BASE_332 FALSE Not FilteredTHREEWALL_989 600 0.91 1.98 4.2 349.02 BASE_332 FALSE Not FilteredTHREEWALL_989 600 0.91 1.98 4.5 270.92 BASE_332 FALSE Not FilteredTHREEWALL_989 600 0.91 1.98 4.8 233.27 BASE_332 FALSE Not Filtered

E-81 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-1 

Obstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Baseline Test Data Filtered Filtration Criteria 

THREEWALL_989 600 0.91 1.98 5.1 202.93 BASE_332 FALSE Not Filtered

THREEWALL_989 600 0.91 1.98 5.4 176.71 BASE_332 FALSE Not FilteredTHREEWALL_989 600 0.91 1.98 5.7 151.1 BASE_332 FALSE Not FilteredTHREEWALL_989 600 0.91 1.98 6 137.61 BASE_332 FALSE Not Filtered

E-82 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Unobstructed Simulation Results 

Table E-2 

Unobstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Heskestad Plume Temperature (Equation 4-3) Data Filtered Filtration Criteria 

BASE_404 1000 0.91 0.30 2.4 795.4 819.38 TRUE

Source Located 1 ft. above Ground

, Heskestad > 800 C

BASE_404 1000 0.91 0.30 2.7 698.73 626.09 TRUE Source Located 1 ft. above GroundBASE_404 1000 0.91 0.30 3 605.33 496.65 TRUE Source Located 1 ft. above GroundBASE_404 1000 0.91 0.30 3.3 507.53 405.28 TRUE Source Located 1 ft. above GroundBASE_404 1000 0.91 0.30 3.6 423.26 338.12 TRUE Source Located 1 ft. above GroundBASE_404 1000 0.91 0.30 3.9 338.41 287.15 TRUE Source Located 1 ft. above GroundBASE_404 1000 0.91 0.30 4.2 282.38 247.45 TRUE Source Located 1 ft. above GroundBASE_404 1000 0.91 0.30 4.5 235.94 215.85 TRUE Source Located 1 ft. above GroundBASE_404 1000 0.91 0.30 4.8 211.9 190.25 TRUE Source Located 1 ft. above GroundBASE_404 1000 0.91 0.30 5.1 189.94 169.19 TRUE Source Located 1 ft. above GroundBASE_404 1000 0.91 0.30 5.4 166.35 151.62 TRUE Source Located 1 ft. above GroundBASE_404 1000 0.91 0.30 5.7 146.53 136.80 TRUE Source Located 1 ft. above GroundBASE_404 1000 0.91 0.30 6 133.59 124.17 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_400 1000 0.91 1.14 2.4 883.35 1000.00 TRUE Heskestad > 800 CBASE_400 1000 0.91 1.14 2.7 869.76 1000.00 TRUE Heskestad > 800 CBASE_400 1000 0.91 1.14 3 821.26 1000.00 TRUE Heskestad > 800 CBASE_400 1000 0.91 1.14 3.3 737.09 772.37 FALSE Not FilteredBASE_400 1000 0.91 1.14 3.6 641.71 595.31 FALSE Not FilteredBASE_400 1000 0.91 1.14 3.9 540.23 475.29 FALSE Not Filtered

E-83 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-2 

Unobstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Heskestad Plume Temperature (Equation 4-3) Data Filtered Filtration Criteria 

BASE_400 1000 0.91 1.14 4.2 442.68 389.79 FALSE Not Filtered

BASE_400 1000 0.91 1.14 4.5 364.05 326.49 FALSE Not FilteredBASE_400 1000 0.91 1.14 4.8 309.85 278.17 FALSE Not FilteredBASE_400 1000 0.91 1.14 5.1 266.48 240.36 FALSE Not FilteredBASE_400 1000 0.91 1.14 5.4 227.22 210.14 FALSE Not FilteredBASE_400 1000 0.91 1.14 5.7 187.04 185.58 FALSE Not FilteredBASE_400 1000 0.91 1.14 6 162.96 165.31 FALSE Not FilteredBASE_401 1000 0.91 1.98 2.4 867.85 1000.00 TRUE Heskestad > 800 CBASE_401 1000 0.91 1.98 2.7 821.69 1000.00 TRUE Heskestad > 800 CBASE_401 1000 0.91 1.98 3 843.29 1000.00 TRUE Heskestad > 800 CBASE_401 1000 0.91 1.98 3.3 863.68 1000.00 TRUE Heskestad > 800 CBASE_401 1000 0.91 1.98 3.6 847.71 1000.00 TRUE Heskestad > 800 CBASE_401 1000 0.91 1.98 3.9 778.57 982.15 TRUE Heskestad > 800 CBASE_401 1000 0.91 1.98 4.2 712.61 729.52 FALSE Not FilteredBASE_401 1000 0.91 1.98 4.5 619.77 566.88 FALSE Not FilteredBASE_401 1000 0.91 1.98 4.8 546.09 455.37 FALSE Not FilteredBASE_401 1000 0.91 1.98 5.1 448.48 375.23 FALSE Not FilteredBASE_401 1000 0.91 1.98 5.4 362.78 315.49 FALSE Not FilteredBASE_401 1000 0.91 1.98 5.7 297.95 269.64 FALSE Not FilteredBASE_401 1000 0.91 1.98 6 255.43 233.59 FALSE Not FilteredBASE_405 1000 1.22 0.30 2.4 781.27 819.38 TRUE

Source Located 1 ft. above Ground

, Heskestad > 800 C

E-84 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-2 

Unobstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Heskestad Plume Temperature (Equation 4-3) Data Filtered Filtration Criteria 

BASE_405 1000 1.22 0.30 2.7 709.22 626.09 TRUE Source Located 1 ft. above Ground

BASE_405 1000 1.22 0.30 3 615.79 496.65 TRUE Source Located 1 ft. above GroundBASE_405 1000 1.22 0.30 3.3 498.02 405.28 TRUE Source Located 1 ft. above GroundBASE_405 1000 1.22 0.30 3.6 410.4 338.12 TRUE Source Located 1 ft. above GroundBASE_405 1000 1.22 0.30 3.9 327.49 287.15 TRUE Source Located 1 ft. above GroundBASE_405 1000 1.22 0.30 4.2 278.55 247.45 TRUE Source Located 1 ft. above GroundBASE_405 1000 1.22 0.30 4.5 237.14 215.85 TRUE Source Located 1 ft. above GroundBASE_405 1000 1.22 0.30 4.8 206.01 190.25 TRUE Source Located 1 ft. above GroundBASE_405 1000 1.22 0.30 5.1 182.4 169.19 TRUE Source Located 1 ft. above GroundBASE_405 1000 1.22 0.30 5.4 160.44 151.62 TRUE Source Located 1 ft. above GroundBASE_405 1000 1.22 0.30 5.7 142.62 136.80 TRUE Source Located 1 ft. above GroundBASE_405 1000 1.22 0.30 6 129.63 124.17 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_402 1000 1.22 1.14 2.4 884.72 1000.00 TRUE Heskestad > 800 CBASE_402 1000 1.22 1.14 2.7 872.06 1000.00 TRUE Heskestad > 800 CBASE_402 1000 1.22 1.14 3 844.23 764.70 FALSE Not FilteredBASE_402 1000 1.22 1.14 3.3 780 590.25 FALSE Not FilteredBASE_402 1000 1.22 1.14 3.6 703.37 471.76 FALSE Not FilteredBASE_402 1000 1.22 1.14 3.9 609.22 387.22 FALSE Not FilteredBASE_402 1000 1.22 1.14 4.2 536.91 324.55 FALSE Not FilteredBASE_402 1000 1.22 1.14 4.5 442.2 276.67 FALSE Not FilteredBASE_402 1000 1.22 1.14 4.8 371.59 239.17 FALSE Not Filtered

E-85 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-2 

Unobstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Heskestad Plume Temperature (Equation 4-3) Data Filtered Filtration Criteria 

BASE_402 1000 1.22 1.14 5.1 319.12 209.19 FALSE Not Filtered

BASE_402 1000 1.22 1.14 5.4 270.59 184.79 FALSE Not FilteredBASE_402 1000 1.22 1.14 5.7 231.36 164.65 FALSE Not FilteredBASE_402 1000 1.22 1.14 6 203.95 147.81 FALSE Not FilteredBASE_403 1000 1.22 1.98 2.4 832.64 1000.00 TRUE Heskestad > 800 CBASE_403 1000 1.22 1.98 2.7 849.5 1000.00 TRUE Heskestad > 800 CBASE_403 1000 1.22 1.98 3 881.01 1000.00 TRUE Heskestad > 800 CBASE_403 1000 1.22 1.98 3.3 897.01 1000.00 TRUE Heskestad > 800 CBASE_403 1000 1.22 1.98 3.6 882.44 970.90 TRUE Heskestad > 800 CBASE_403 1000 1.22 1.98 3.9 843.66 722.52 FALSE Not FilteredBASE_403 1000 1.22 1.98 4.2 798.56 562.20 FALSE Not FilteredBASE_403 1000 1.22 1.98 4.5 714.56 452.07 FALSE Not FilteredBASE_403 1000 1.22 1.98 4.8 619.77 372.81 FALSE Not FilteredBASE_403 1000 1.22 1.98 5.1 524.43 313.65 FALSE Not FilteredBASE_403 1000 1.22 1.98 5.4 430.81 268.21 FALSE Not FilteredBASE_403 1000 1.22 1.98 5.7 350.83 232.45 FALSE Not FilteredBASE_403 1000 1.22 1.98 6 294.37 203.75 FALSE Not FilteredBASE_300 50 0.30 0.30 2.4 78.578 85.19 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_300 50 0.30 0.30 2.7 62.259 67.56 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_300 50 0.30 0.30 3 51.393 55.11 TRUE Heskestad < 130 C , Source

E-86 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-2 

Unobstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Heskestad Plume Temperature (Equation 4-3) Data Filtered Filtration Criteria 

Located 1 ft. above Ground

BASE_300 50 0.30 0.30 3.3 42.918 45.97 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_300 50 0.30 0.30 3.6 38.301 39.03 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_300 50 0.30 0.30 3.9 33.654 33.63 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_301 100 0.30 0.30 2.4 144.68 150.77 TRUE Source Located 1 ft. above GroundBASE_301 100 0.30 0.30 2.7 115.38 117.84 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_301 100 0.30 0.30 3 94.51 95.07 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_301 100 0.30 0.30 3.3 78.22 78.61 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_301 100 0.30 0.30 3.6 66.281 66.27 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_301 100 0.30 0.30 3.9 54.636 56.77 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_301 100 0.30 0.30 4.2 48.663 49.27 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_301 100 0.30 0.30 4.5 44.269 43.24 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_301 100 0.30 0.30 4.8 41.438 38.31 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_311 50 0.30 1.14 2.4 191.73 209.49 FALSE Not FilteredBASE_311 50 0.30 1.14 2.7 132.04 143.24 FALSE Not Filtered

E-87 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-2 

Unobstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Heskestad Plume Temperature (Equation 4-3) Data Filtered Filtration Criteria 

BASE_311 50 0.30 1.14 3 103.75 105.13 TRUE Heskestad < 130 C

BASE_311 50 0.30 1.14 3.3 80.93 81.00 TRUE Heskestad < 130 CBASE_311 50 0.30 1.14 3.6 66.604 64.65 TRUE Heskestad < 130 CBASE_311 50 0.30 1.14 3.9 54.69 53.01 TRUE Heskestad < 130 CBASE_311 50 0.30 1.14 4.2 47.827 44.39 TRUE Heskestad < 130 CBASE_312 100 0.30 1.14 2.4 362.7 402.61 FALSE Not FilteredBASE_312 100 0.30 1.14 2.7 221.13 264.28 FALSE Not FilteredBASE_312 100 0.30 1.14 3 162.78 188.91 FALSE Not FilteredBASE_312 100 0.30 1.14 3.3 123.92 142.87 FALSE Not FilteredBASE_312 100 0.30 1.14 3.6 99.71 112.48 TRUE Heskestad < 130 CBASE_312 100 0.30 1.14 3.9 82.29 91.25 TRUE Heskestad < 130 CBASE_312 100 0.30 1.14 4.2 70.911 75.78 TRUE Heskestad < 130 CBASE_312 100 0.30 1.14 4.5 58.39 64.12 TRUE Heskestad < 130 CBASE_312 100 0.30 1.14 4.8 51.09 55.08 TRUE Heskestad < 130 CBASE_312 100 0.30 1.14 5.1 44.749 47.92 TRUE Heskestad < 130 CBASE_312 100 0.30 1.14 5.4 39.094 42.15 TRUE Heskestad < 130 CBASE_322 50 0.30 1.98 2.4 790.05 1000.00 TRUE Heskestad > 800 CBASE_322 50 0.30 1.98 2.7 434.88 584.26 FALSE Not FilteredBASE_322 50 0.30 1.98 3 242.82 306.03 FALSE Not FilteredBASE_322 50 0.30 1.98 3.3 154.53 192.28 FALSE Not FilteredBASE_322 50 0.30 1.98 3.6 115.32 133.75 FALSE Not Filtered

E-88 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-2 

Unobstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Heskestad Plume Temperature (Equation 4-3) Data Filtered Filtration Criteria 

BASE_322 50 0.30 1.98 3.9 89.33 99.29 TRUE Heskestad < 130 C

BASE_322 50 0.30 1.98 4.2 71.831 77.12 TRUE Heskestad < 130 CBASE_322 50 0.30 1.98 4.5 56.449 61.93 TRUE Heskestad < 130 CBASE_322 50 0.30 1.98 4.8 46.519 51.02 TRUE Heskestad < 130 CBASE_322 50 0.30 1.98 5.1 40.578 42.89 TRUE Heskestad < 130 CBASE_323 100 0.30 1.98 2.4 1020.6 1000.00 TRUE Heskestad > 800 CBASE_323 100 0.30 1.98 2.7 908.31 1000.00 TRUE Heskestad > 800 CBASE_323 100 0.30 1.98 3 614.44 619.87 FALSE Not FilteredBASE_323 100 0.30 1.98 3.3 348.63 365.81 FALSE Not FilteredBASE_323 100 0.30 1.98 3.6 238.38 245.21 FALSE Not FilteredBASE_323 100 0.30 1.98 3.9 165.26 177.64 FALSE Not FilteredBASE_323 100 0.30 1.98 4.2 127.9 135.61 FALSE Not FilteredBASE_323 100 0.30 1.98 4.5 99.95 107.50 TRUE Heskestad < 130 CBASE_323 100 0.30 1.98 4.8 84.38 87.67 TRUE Heskestad < 130 CBASE_323 100 0.30 1.98 5.1 70.453 73.11 TRUE Heskestad < 130 CBASE_323 100 0.30 1.98 5.4 58.577 62.07 TRUE Heskestad < 130 CBASE_323 100 0.30 1.98 5.7 50.134 53.47 TRUE Heskestad < 130 CBASE_323 100 0.30 1.98 6 43.943 46.64 TRUE Heskestad < 130 CBASE_302 200 0.61 0.30 2.4 213.45 211.71 TRUE Source Located 1 ft. above GroundBASE_302 200 0.61 0.30 2.7 170.01 168.19 TRUE Source Located 1 ft. above GroundBASE_302 200 0.61 0.30 3 142.96 137.40 TRUE Source Located 1 ft. above Ground

E-89 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-2 

Unobstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Heskestad Plume Temperature (Equation 4-3) Data Filtered Filtration Criteria 

BASE_302 200 0.61 0.30 3.3 121.27 114.73 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_302 200 0.61 0.30 3.6 105.52 97.51 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_302 200 0.61 0.30 3.9 88.62 84.08 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_302 200 0.61 0.30 4.2 76.736 73.38 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_302 200 0.61 0.30 4.5 67.501 64.71 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_302 200 0.61 0.30 4.8 61.141 57.56 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_302 200 0.61 0.30 5.1 56.723 51.60 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_302 200 0.61 0.30 5.4 51.975 46.57 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_302 200 0.61 0.30 5.7 45.998 42.28 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_302 200 0.61 0.30 6 43.08 38.59 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_303 300 0.61 0.30 2.4 296.14 307.62 TRUE Source Located 1 ft. above GroundBASE_303 300 0.61 0.30 2.7 220.38 241.06 TRUE Source Located 1 ft. above GroundBASE_303 300 0.61 0.30 3 183.17 194.88 TRUE Source Located 1 ft. above GroundBASE_303 300 0.61 0.30 3.3 148.23 161.39 TRUE Source Located 1 ft. above GroundBASE_303 300 0.61 0.30 3.6 128.16 136.24 TRUE Source Located 1 ft. above Ground

E-90 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-2 

Unobstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Heskestad Plume Temperature (Equation 4-3) Data Filtered Filtration Criteria 

BASE_303 300 0.61 0.30 3.9 108.27 116.82 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_303 300 0.61 0.30 4.2 93.85 101.48 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_303 300 0.61 0.30 4.5 81.84 89.13 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_303 300 0.61 0.30 4.8 74.599 79.02 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_303 300 0.61 0.30 5.1 67.063 70.63 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_303 300 0.61 0.30 5.4 60.342 63.57 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_303 300 0.61 0.30 5.7 53.847 57.58 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_303 300 0.61 0.30 6 50.33 52.45 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_304 400 0.61 0.30 2.4 411.81 407.41 TRUE Source Located 1 ft. above GroundBASE_304 400 0.61 0.30 2.7 304.43 315.31 TRUE Source Located 1 ft. above GroundBASE_304 400 0.61 0.30 3 247.49 252.53 TRUE Source Located 1 ft. above GroundBASE_304 400 0.61 0.30 3.3 200.37 207.60 TRUE Source Located 1 ft. above GroundBASE_304 400 0.61 0.30 3.6 162.17 174.22 TRUE Source Located 1 ft. above GroundBASE_304 400 0.61 0.30 3.9 133.24 148.67 TRUE Source Located 1 ft. above GroundBASE_304 400 0.61 0.30 4.2 115.82 128.63 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_304 400 0.61 0.30 4.5 101.45 112.58 TRUE Heskestad < 130 C , Source

E-91 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-2 

Unobstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Heskestad Plume Temperature (Equation 4-3) Data Filtered Filtration Criteria 

Located 1 ft. above Ground

BASE_304 400 0.61 0.30 4.8 90.29 99.52 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_304 400 0.61 0.30 5.1 82.61 88.72 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_304 400 0.61 0.30 5.4 75.416 79.68 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_304 400 0.61 0.30 5.7 69.567 72.03 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_304 400 0.61 0.30 6 64.731 65.49 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_305 500 0.61 0.30 2.4 521.63 512.32 TRUE Source Located 1 ft. above GroundBASE_305 500 0.61 0.30 2.7 399.1 391.90 TRUE Source Located 1 ft. above GroundBASE_305 500 0.61 0.30 3 316.2 311.14 TRUE Source Located 1 ft. above GroundBASE_305 500 0.61 0.30 3.3 246.46 254.06 TRUE Source Located 1 ft. above GroundBASE_305 500 0.61 0.30 3.6 196.89 212.07 TRUE Source Located 1 ft. above GroundBASE_305 500 0.61 0.30 3.9 156 180.17 TRUE Source Located 1 ft. above GroundBASE_305 500 0.61 0.30 4.2 135.57 155.31 TRUE Source Located 1 ft. above GroundBASE_305 500 0.61 0.30 4.5 118.31 135.52 TRUE Source Located 1 ft. above GroundBASE_305 500 0.61 0.30 4.8 101.09 119.48 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_305 500 0.61 0.30 5.1 90.49 106.27 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_305 500 0.61 0.30 5.4 82.81 95.25 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

E-92 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-2 

Unobstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Heskestad Plume Temperature (Equation 4-3) Data Filtered Filtration Criteria 

BASE_305 500 0.61 0.30 5.7 77.621 85.96 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_305 500 0.61 0.30 6 72.416 78.03 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_306 600 0.61 0.30 2.4 621.32 623.47 TRUE Source Located 1 ft. above GroundBASE_306 600 0.61 0.30 2.7 493.05 471.55 TRUE Source Located 1 ft. above GroundBASE_306 600 0.61 0.30 3 392.91 371.26 TRUE Source Located 1 ft. above GroundBASE_306 600 0.61 0.30 3.3 300.99 301.22 TRUE Source Located 1 ft. above GroundBASE_306 600 0.61 0.30 3.6 239.8 250.16 TRUE Source Located 1 ft. above GroundBASE_306 600 0.61 0.30 3.9 196.28 211.66 TRUE Source Located 1 ft. above GroundBASE_306 600 0.61 0.30 4.2 168.47 181.84 TRUE Source Located 1 ft. above GroundBASE_306 600 0.61 0.30 4.5 143.2 158.21 TRUE Source Located 1 ft. above GroundBASE_306 600 0.61 0.30 4.8 127.89 139.14 TRUE Source Located 1 ft. above GroundBASE_306 600 0.61 0.30 5.1 116.33 123.50 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_306 600 0.61 0.30 5.4 106.77 110.49 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_306 600 0.61 0.30 5.7 95.54 99.55 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_306 600 0.61 0.30 6 87.35 90.24 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_313 200 0.61 1.14 2.4 600.42 515.47 FALSE Not FilteredBASE_313 200 0.61 1.14 2.7 414.5 354.17 FALSE Not FilteredBASE_313 200 0.61 1.14 3 309.8 260.78 FALSE Not Filtered

E-93 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-2 

Unobstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Heskestad Plume Temperature (Equation 4-3) Data Filtered Filtration Criteria 

BASE_313 200 0.61 1.14 3.3 229.95 201.37 FALSE Not Filtered

BASE_313 200 0.61 1.14 3.6 175.92 160.99 FALSE Not FilteredBASE_313 200 0.61 1.14 3.9 133.61 132.18 FALSE Not FilteredBASE_313 200 0.61 1.14 4.2 112.07 110.81 TRUE Heskestad < 130 CBASE_313 200 0.61 1.14 4.5 97.7 94.47 TRUE Heskestad < 130 CBASE_313 200 0.61 1.14 4.8 86.66 81.68 TRUE Heskestad < 130 CBASE_313 200 0.61 1.14 5.1 76.924 71.45 TRUE Heskestad < 130 CBASE_313 200 0.61 1.14 5.4 69.128 63.12 TRUE Heskestad < 130 CBASE_313 200 0.61 1.14 5.7 62.155 56.25 TRUE Heskestad < 130 CBASE_313 200 0.61 1.14 6 57.725 50.50 TRUE Heskestad < 130 CBASE_314 300 0.61 1.14 2.4 794.04 808.95 TRUE Heskestad > 800 CBASE_314 300 0.61 1.14 2.7 633.17 535.11 FALSE Not FilteredBASE_314 300 0.61 1.14 3 494.2 384.36 FALSE Not FilteredBASE_314 300 0.61 1.14 3.3 355.45 291.68 FALSE Not FilteredBASE_314 300 0.61 1.14 3.6 273.81 230.20 FALSE Not FilteredBASE_314 300 0.61 1.14 3.9 207.36 187.12 FALSE Not FilteredBASE_314 300 0.61 1.14 4.2 174.38 155.63 FALSE Not FilteredBASE_314 300 0.61 1.14 4.5 143.36 131.83 FALSE Not FilteredBASE_314 300 0.61 1.14 4.8 125.13 113.37 TRUE Heskestad < 130 CBASE_314 300 0.61 1.14 5.1 106.46 98.72 TRUE Heskestad < 130 CBASE_314 300 0.61 1.14 5.4 91.29 86.88 TRUE Heskestad < 130 C

E-94 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-2 

Unobstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Heskestad Plume Temperature (Equation 4-3) Data Filtered Filtration Criteria 

BASE_314 300 0.61 1.14 5.7 81.09 77.16 TRUE Heskestad < 130 C

BASE_314 300 0.61 1.14 6 73.481 69.07 TRUE Heskestad < 130 CBASE_315 400 0.61 1.14 2.4 894.49 1000.00 TRUE Heskestad > 800 CBASE_315 400 0.61 1.14 2.7 791.96 735.01 FALSE Not FilteredBASE_315 400 0.61 1.14 3 664.52 515.78 FALSE Not FilteredBASE_315 400 0.61 1.14 3.3 488.44 385.18 FALSE Not FilteredBASE_315 400 0.61 1.14 3.6 370.93 300.47 FALSE Not FilteredBASE_315 400 0.61 1.14 3.9 277.21 242.07 FALSE Not FilteredBASE_315 400 0.61 1.14 4.2 223.36 199.93 FALSE Not FilteredBASE_315 400 0.61 1.14 4.5 175.71 168.41 FALSE Not FilteredBASE_315 400 0.61 1.14 4.8 149.38 144.15 FALSE Not FilteredBASE_315 400 0.61 1.14 5.1 132.48 125.03 TRUE Heskestad < 130 CBASE_315 400 0.61 1.14 5.4 116.77 109.68 TRUE Heskestad < 130 CBASE_315 400 0.61 1.14 5.7 102.83 97.13 TRUE Heskestad < 130 CBASE_315 400 0.61 1.14 6 93.62 86.73 TRUE Heskestad < 130 CBASE_316 500 0.61 1.14 2.4 879.86 1000.00 TRUE Heskestad > 800 CBASE_316 500 0.61 1.14 2.7 792.75 957.56 TRUE Heskestad > 800 CBASE_316 500 0.61 1.14 3 694.1 656.81 FALSE Not FilteredBASE_316 500 0.61 1.14 3.3 573.87 483.05 FALSE Not FilteredBASE_316 500 0.61 1.14 3.6 456.09 372.71 FALSE Not FilteredBASE_316 500 0.61 1.14 3.9 339.35 297.80 FALSE Not Filtered

E-95 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-2 

Unobstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Heskestad Plume Temperature (Equation 4-3) Data Filtered Filtration Criteria 

BASE_316 500 0.61 1.14 4.2 277.73 244.38 FALSE Not Filtered

BASE_316 500 0.61 1.14 4.5 223.54 204.79 FALSE Not FilteredBASE_316 500 0.61 1.14 4.8 182.29 174.55 FALSE Not FilteredBASE_316 500 0.61 1.14 5.1 155.41 150.87 FALSE Not FilteredBASE_316 500 0.61 1.14 5.4 133.98 131.94 FALSE Not FilteredBASE_316 500 0.61 1.14 5.7 119.94 116.55 TRUE Heskestad < 130 CBASE_316 500 0.61 1.14 6 108.39 103.84 TRUE Heskestad < 130 CBASE_317 600 0.61 1.14 2.4 908.01 1000.00 TRUE Heskestad > 800 CBASE_317 600 0.61 1.14 2.7 864.94 1000.00 TRUE Heskestad > 800 CBASE_317 600 0.61 1.14 3 781.95 809.22 TRUE Heskestad > 800 CBASE_317 600 0.61 1.14 3.3 647.71 586.29 FALSE Not FilteredBASE_317 600 0.61 1.14 3.6 534.14 447.60 FALSE Not FilteredBASE_317 600 0.61 1.14 3.9 416.5 354.83 FALSE Not FilteredBASE_317 600 0.61 1.14 4.2 328.89 289.41 FALSE Not FilteredBASE_317 600 0.61 1.14 4.5 264.69 241.36 FALSE Not FilteredBASE_317 600 0.61 1.14 4.8 222.42 204.91 FALSE Not FilteredBASE_317 600 0.61 1.14 5.1 186.54 176.53 FALSE Not FilteredBASE_317 600 0.61 1.14 5.4 158.69 153.95 FALSE Not FilteredBASE_317 600 0.61 1.14 5.7 136.29 135.67 FALSE Not FilteredBASE_317 600 0.61 1.14 6 123.49 120.63 TRUE Heskestad < 130 CBASE_324 200 0.61 1.98 2.4 802.19 1000.00 TRUE Heskestad > 800 C

E-96 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-2 

Unobstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Heskestad Plume Temperature (Equation 4-3) Data Filtered Filtration Criteria 

BASE_324 200 0.61 1.98 2.7 812.66 1000.00 TRUE Heskestad > 800 C

BASE_324 200 0.61 1.98 3 680.91 748.51 FALSE Not FilteredBASE_324 200 0.61 1.98 3.3 486.99 473.69 FALSE Not FilteredBASE_324 200 0.61 1.98 3.6 354.53 330.95 FALSE Not FilteredBASE_324 200 0.61 1.98 3.9 255.02 246.42 FALSE Not FilteredBASE_324 200 0.61 1.98 4.2 205.62 191.81 FALSE Not FilteredBASE_324 200 0.61 1.98 4.5 166.23 154.28 FALSE Not FilteredBASE_324 200 0.61 1.98 4.8 136.56 127.26 TRUE Heskestad < 130 CBASE_324 200 0.61 1.98 5.1 115.36 107.09 TRUE Heskestad < 130 CBASE_324 200 0.61 1.98 5.4 98.47 91.59 TRUE Heskestad < 130 CBASE_324 200 0.61 1.98 5.7 83.73 79.39 TRUE Heskestad < 130 CBASE_324 200 0.61 1.98 6 73.846 69.59 TRUE Heskestad < 130 CBASE_325 300 0.61 1.98 2.4 834.33 1000.00 TRUE Heskestad > 800 CBASE_325 300 0.61 1.98 2.7 924.98 1000.00 TRUE Heskestad > 800 CBASE_325 300 0.61 1.98 3 881.51 1000.00 TRUE Heskestad > 800 CBASE_325 300 0.61 1.98 3.3 729.09 736.43 FALSE Not FilteredBASE_325 300 0.61 1.98 3.6 570.95 497.07 FALSE Not FilteredBASE_325 300 0.61 1.98 3.9 413.79 361.73 FALSE Not FilteredBASE_325 300 0.61 1.98 4.2 313.04 277.01 FALSE Not FilteredBASE_325 300 0.61 1.98 4.5 224.91 220.11 FALSE Not FilteredBASE_325 300 0.61 1.98 4.8 177.16 179.84 FALSE Not Filtered

E-97 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-2 

Unobstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Heskestad Plume Temperature (Equation 4-3) Data Filtered Filtration Criteria 

BASE_325 300 0.61 1.98 5.1 150.9 150.19 FALSE Not Filtered

BASE_325 300 0.61 1.98 5.4 129.86 127.65 TRUE Heskestad < 130 CBASE_325 300 0.61 1.98 5.7 107.49 110.08 TRUE Heskestad < 130 CBASE_325 300 0.61 1.98 6 94.42 96.08 TRUE Heskestad < 130 CBASE_326 400 0.61 1.98 2.4 847.41 1000.00 TRUE Heskestad > 800 CBASE_326 400 0.61 1.98 2.7 909.47 1000.00 TRUE Heskestad > 800 CBASE_326 400 0.61 1.98 3 917.03 1000.00 TRUE Heskestad > 800 CBASE_326 400 0.61 1.98 3.3 850.04 1000.00 TRUE Heskestad > 800 CBASE_326 400 0.61 1.98 3.6 715.9 678.92 FALSE Not FilteredBASE_326 400 0.61 1.98 3.9 558.26 483.57 FALSE Not FilteredBASE_326 400 0.61 1.98 4.2 402.99 364.83 FALSE Not FilteredBASE_326 400 0.61 1.98 4.5 294.05 286.71 FALSE Not FilteredBASE_326 400 0.61 1.98 4.8 235.69 232.29 FALSE Not FilteredBASE_326 400 0.61 1.98 5.1 201.69 192.70 FALSE Not FilteredBASE_326 400 0.61 1.98 5.4 168.14 162.90 FALSE Not FilteredBASE_326 400 0.61 1.98 5.7 139.4 139.84 FALSE Not FilteredBASE_326 400 0.61 1.98 6 119.04 121.60 TRUE Heskestad < 130 CBASE_327 500 0.61 1.98 2.4 869.39 1000.00 TRUE Heskestad > 800 CBASE_327 500 0.61 1.98 2.7 904.4 1000.00 TRUE Heskestad > 800 CBASE_327 500 0.61 1.98 3 946.1 1000.00 TRUE Heskestad > 800 CBASE_327 500 0.61 1.98 3.3 913.68 1000.00 TRUE Heskestad > 800 C

E-98 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-2 

Unobstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Heskestad Plume Temperature (Equation 4-3) Data Filtered Filtration Criteria 

BASE_327 500 0.61 1.98 3.6 812.4 879.58 TRUE Heskestad > 800 C

BASE_327 500 0.61 1.98 3.9 650.44 613.57 FALSE Not FilteredBASE_327 500 0.61 1.98 4.2 526.14 456.37 FALSE Not FilteredBASE_327 500 0.61 1.98 4.5 415.12 354.97 FALSE Not FilteredBASE_327 500 0.61 1.98 4.8 327.36 285.36 FALSE Not FilteredBASE_327 500 0.61 1.98 5.1 261.93 235.27 FALSE Not FilteredBASE_327 500 0.61 1.98 5.4 213.41 197.91 FALSE Not FilteredBASE_327 500 0.61 1.98 5.7 181.16 169.21 FALSE Not FilteredBASE_327 500 0.61 1.98 6 158.89 146.63 FALSE Not FilteredBASE_328 600 0.61 1.98 2.4 896.1  ‐20.00 TRUE Heskestad < 130 CBASE_328 600 0.61 1.98 2.7 892.48 1000.00 TRUE Heskestad > 800 CBASE_328 600 0.61 1.98 3 908.94 1000.00 TRUE Heskestad > 800 CBASE_328 600 0.61 1.98 3.3 936.98 1000.00 TRUE Heskestad > 800 CBASE_328 600 0.61 1.98 3.6 907.68 1000.00 TRUE Heskestad > 800 CBASE_328 600 0.61 1.98 3.9 782.46 753.25 FALSE Not FilteredBASE_328 600 0.61 1.98 4.2 650.93 552.54 FALSE Not FilteredBASE_328 600 0.61 1.98 4.5 501.29 425.53 FALSE Not FilteredBASE_328 600 0.61 1.98 4.8 397.92 339.54 FALSE Not FilteredBASE_328 600 0.61 1.98 5.1 314.02 278.32 FALSE Not FilteredBASE_328 600 0.61 1.98 5.4 250.3 233.04 FALSE Not FilteredBASE_328 600 0.61 1.98 5.7 213.26 198.49 FALSE Not Filtered

E-99 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-2 

Unobstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Heskestad Plume Temperature (Equation 4-3) Data Filtered Filtration Criteria 

BASE_328 600 0.61 1.98 6 176.59 171.46 FALSE Not Filtered

BASE_307 300 0.91 0.30 2.4 294.61 239.11 TRUE Source Located 1 ft. above GroundBASE_307 300 0.91 0.30 2.7 233.57 193.49 TRUE Source Located 1 ft. above GroundBASE_307 300 0.91 0.30 3 194.58 160.36 TRUE Source Located 1 ft. above GroundBASE_307 300 0.91 0.30 3.3 158.8 135.45 TRUE Source Located 1 ft. above GroundBASE_307 300 0.91 0.30 3.6 133.72 116.21 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_307 300 0.91 0.30 3.9 110.18 100.99 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_307 300 0.91 0.30 4.2 97.21 88.73 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_307 300 0.91 0.30 4.5 84.82 78.69 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_307 300 0.91 0.30 4.8 76.364 70.35 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_307 300 0.91 0.30 5.1 68.72 63.34 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_307 300 0.91 0.30 5.4 61.382 57.39 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_307 300 0.91 0.30 5.7 56.444 52.28 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_307 300 0.91 0.30 6 52.33 47.86 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_308 400 0.91 0.30 2.4 378.29 312.56 TRUE Source Located 1 ft. above GroundBASE_308 400 0.91 0.30 2.7 287.23 250.60 TRUE Source Located 1 ft. above Ground

E-100 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-2 

Unobstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Heskestad Plume Temperature (Equation 4-3) Data Filtered Filtration Criteria 

BASE_308 400 0.91 0.30 3 227.12 206.19 TRUE Source Located 1 ft. above Ground

BASE_308 400 0.91 0.30 3.3 180.15 173.15 TRUE Source Located 1 ft. above GroundBASE_308 400 0.91 0.30 3.6 154.74 147.84 TRUE Source Located 1 ft. above GroundBASE_308 400 0.91 0.30 3.9 130.12 127.97 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_308 400 0.91 0.30 4.2 112.85 112.05 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_308 400 0.91 0.30 4.5 99.44 99.08 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_308 400 0.91 0.30 4.8 89.37 88.36 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_308 400 0.91 0.30 5.1 80.38 79.38 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_308 400 0.91 0.30 5.4 72.991 71.77 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_308 400 0.91 0.30 5.7 66.197 65.27 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_308 400 0.91 0.30 6 62.1 59.66 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_309 500 0.91 0.30 2.4 530.61 388.34 TRUE Source Located 1 ft. above GroundBASE_309 500 0.91 0.30 2.7 399.64 308.67 TRUE Source Located 1 ft. above GroundBASE_309 500 0.91 0.30 3 316.36 252.27 TRUE Source Located 1 ft. above GroundBASE_309 500 0.91 0.30 3.3 253.48 210.73 TRUE Source Located 1 ft. above GroundBASE_309 500 0.91 0.30 3.6 211.54 179.14 TRUE Source Located 1 ft. above Ground

E-101 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-2 

Unobstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Heskestad Plume Temperature (Equation 4-3) Data Filtered Filtration Criteria 

BASE_309 500 0.91 0.30 3.9 173.13 154.50 TRUE Source Located 1 ft. above Ground

BASE_309 500 0.91 0.30 4.2 149.53 134.87 TRUE Source Located 1 ft. above GroundBASE_309 500 0.91 0.30 4.5 131.51 118.94 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_309 500 0.91 0.30 4.8 116.85 105.83 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_309 500 0.91 0.30 5.1 100.39 94.88 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_309 500 0.91 0.30 5.4 89.79 85.64 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_309 500 0.91 0.30 5.7 81.01 77.76 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_309 500 0.91 0.30 6 75.255 70.98 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_310 600 0.91 0.30 2.4 596.83 467.23 TRUE Source Located 1 ft. above GroundBASE_310 600 0.91 0.30 2.7 462.19 368.31 TRUE Source Located 1 ft. above GroundBASE_310 600 0.91 0.30 3 379.52 299.11 TRUE Source Located 1 ft. above GroundBASE_310 600 0.91 0.30 3.3 298.51 248.59 TRUE Source Located 1 ft. above GroundBASE_310 600 0.91 0.30 3.6 243.35 210.46 TRUE Source Located 1 ft. above GroundBASE_310 600 0.91 0.30 3.9 196.5 180.89 TRUE Source Located 1 ft. above GroundBASE_310 600 0.91 0.30 4.2 172.41 157.46 TRUE Source Located 1 ft. above GroundBASE_310 600 0.91 0.30 4.5 150.21 138.53 TRUE Source Located 1 ft. above GroundBASE_310 600 0.91 0.30 4.8 136 122.99 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

E-102 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-2 

Unobstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Heskestad Plume Temperature (Equation 4-3) Data Filtered Filtration Criteria 

BASE_310 600 0.91 0.30 5.1 121.42 110.07 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_310 600 0.91 0.30 5.4 106.73 99.19 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_310 600 0.91 0.30 5.7 96.21 89.93 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_310 600 0.91 0.30 6 87.94 81.98 TRUE

Heskestad < 130 C , Source

Located 1 ft. above Ground

BASE_318 300 0.91 1.14 2.4 692.22 528.15 FALSE Not FilteredBASE_318 300 0.91 1.14 2.7 538.13 380.26 FALSE Not FilteredBASE_318 300 0.91 1.14 3 417.48 289.03 FALSE Not FilteredBASE_318 300 0.91 1.14 3.3 314.68 228.39 FALSE Not FilteredBASE_318 300 0.91 1.14 3.6 259.57 185.82 FALSE Not FilteredBASE_318 300 0.91 1.14 3.9 205.38 154.66 FALSE Not FilteredBASE_318 300 0.91 1.14 4.2 170.6 131.09 FALSE Not FilteredBASE_318 300 0.91 1.14 4.5 142.25 112.79 TRUE Heskestad < 130 CBASE_318 300 0.91 1.14 4.8 125.76 98.25 TRUE Heskestad < 130 CBASE_318 300 0.91 1.14 5.1 109.41 86.50 TRUE Heskestad < 130 CBASE_318 300 0.91 1.14 5.4 97.66 76.85 TRUE Heskestad < 130 CBASE_318 300 0.91 1.14 5.7 88.61 68.81 TRUE Heskestad < 130 CBASE_318 300 0.91 1.14 6 79.48 62.04 TRUE Heskestad < 130 CBASE_319 400 0.91 1.14 2.4 776.45 724.41 FALSE Not FilteredBASE_319 400 0.91 1.14 2.7 661.63 509.75 FALSE Not Filtered

E-103 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-2 

Unobstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Heskestad Plume Temperature (Equation 4-3) Data Filtered Filtration Criteria 

BASE_319 400 0.91 1.14 3 527.06 381.39 FALSE Not Filtered

BASE_319 400 0.91 1.14 3.3 401.4 297.92 FALSE Not FilteredBASE_319 400 0.91 1.14 3.6 320.13 240.27 FALSE Not FilteredBASE_319 400 0.91 1.14 3.9 245.06 198.60 FALSE Not FilteredBASE_319 400 0.91 1.14 4.2 201.27 167.40 FALSE Not FilteredBASE_319 400 0.91 1.14 4.5 164.98 143.36 FALSE Not FilteredBASE_319 400 0.91 1.14 4.8 140.84 124.41 TRUE Heskestad < 130 CBASE_319 400 0.91 1.14 5.1 123.14 109.17 TRUE Heskestad < 130 CBASE_319 400 0.91 1.14 5.4 104.51 96.71 TRUE Heskestad < 130 CBASE_319 400 0.91 1.14 5.7 91.71 86.38 TRUE Heskestad < 130 CBASE_319 400 0.91 1.14 6 81.9 77.71 TRUE Heskestad < 130 CBASE_320 500 0.91 1.14 2.4 840.34 942.74 TRUE Heskestad > 800 CBASE_320 500 0.91 1.14 2.7 756.11 648.67 FALSE Not FilteredBASE_320 500 0.91 1.14 3 644.4 478.07 FALSE Not FilteredBASE_320 500 0.91 1.14 3.3 513.15 369.41 FALSE Not FilteredBASE_320 500 0.91 1.14 3.6 405.57 295.50 FALSE Not FilteredBASE_320 500 0.91 1.14 3.9 313.67 242.70 FALSE Not FilteredBASE_320 500 0.91 1.14 4.2 259.89 203.52 FALSE Not FilteredBASE_320 500 0.91 1.14 4.5 213.94 173.57 FALSE Not FilteredBASE_320 500 0.91 1.14 4.8 176.05 150.10 FALSE Not FilteredBASE_320 500 0.91 1.14 5.1 151.54 131.32 FALSE Not Filtered

E-104 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-2 

Unobstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Heskestad Plume Temperature (Equation 4-3) Data Filtered Filtration Criteria 

BASE_320 500 0.91 1.14 5.4 128.29 116.03 TRUE Heskestad < 130 C

BASE_320 500 0.91 1.14 5.7 109.45 103.41 TRUE Heskestad < 130 CBASE_320 500 0.91 1.14 6 96.93 92.85 TRUE Heskestad < 130 CBASE_321 600 0.91 1.14 2.4 889.62 1000.00 TRUE Heskestad > 800 CBASE_321 600 0.91 1.14 2.7 821.75 799.00 FALSE Not FilteredBASE_321 600 0.91 1.14 3 702.23 580.18 FALSE Not FilteredBASE_321 600 0.91 1.14 3.3 572.03 443.62 FALSE Not FilteredBASE_321 600 0.91 1.14 3.6 458.85 352.09 FALSE Not FilteredBASE_321 600 0.91 1.14 3.9 366.35 287.43 FALSE Not FilteredBASE_321 600 0.91 1.14 4.2 299.58 239.87 FALSE Not FilteredBASE_321 600 0.91 1.14 4.5 246.77 203.76 FALSE Not FilteredBASE_321 600 0.91 1.14 4.8 205.76 175.63 FALSE Not FilteredBASE_321 600 0.91 1.14 5.1 181.11 153.23 FALSE Not FilteredBASE_321 600 0.91 1.14 5.4 153.17 135.08 FALSE Not FilteredBASE_321 600 0.91 1.14 5.7 130.5 120.14 TRUE Heskestad < 130 CBASE_321 600 0.91 1.14 6 116.01 107.67 TRUE Heskestad < 130 CBASE_329 300 0.91 1.98 2.4 786.08 1000.00 TRUE Heskestad > 800 CBASE_329 300 0.91 1.98 2.7 833.93 1000.00 TRUE Heskestad > 800 CBASE_329 300 0.91 1.98 3 779.18 724.86 FALSE Not FilteredBASE_329 300 0.91 1.98 3.3 642.61 490.88 FALSE Not FilteredBASE_329 300 0.91 1.98 3.6 503.08 358.00 FALSE Not Filtered

E-105 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-2 

Unobstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Heskestad Plume Temperature (Equation 4-3) Data Filtered Filtration Criteria 

BASE_329 300 0.91 1.98 3.9 371.31 274.58 FALSE Not Filtered

BASE_329 300 0.91 1.98 4.2 288.47 218.42 FALSE Not FilteredBASE_329 300 0.91 1.98 4.5 214 178.62 FALSE Not FilteredBASE_329 300 0.91 1.98 4.8 173.05 149.28 FALSE Not FilteredBASE_329 300 0.91 1.98 5.1 148.51 126.95 TRUE Heskestad < 130 CBASE_329 300 0.91 1.98 5.4 127.52 109.52 TRUE Heskestad < 130 CBASE_329 300 0.91 1.98 5.7 112.57 95.63 TRUE Heskestad < 130 CBASE_329 300 0.91 1.98 6 97.15 84.36 TRUE Heskestad < 130 CBASE_330 400 0.91 1.98 2.4 774.29 1000.00 TRUE Heskestad > 800 CBASE_330 400 0.91 1.98 2.7 859.64 1000.00 TRUE Heskestad > 800 CBASE_330 400 0.91 1.98 3 856.89 1000.00 TRUE Heskestad > 800 CBASE_330 400 0.91 1.98 3.3 771.36 669.58 FALSE Not FilteredBASE_330 400 0.91 1.98 3.6 659.28 478.13 FALSE Not FilteredBASE_330 400 0.91 1.98 3.9 496.43 361.36 FALSE Not FilteredBASE_330 400 0.91 1.98 4.2 394.1 284.35 FALSE Not FilteredBASE_330 400 0.91 1.98 4.5 308.32 230.60 FALSE Not FilteredBASE_330 400 0.91 1.98 4.8 249.53 191.45 FALSE Not FilteredBASE_330 400 0.91 1.98 5.1 198.13 161.94 FALSE Not FilteredBASE_330 400 0.91 1.98 5.4 160.84 139.09 FALSE Not FilteredBASE_330 400 0.91 1.98 5.7 138.31 121.00 TRUE Heskestad < 130 CBASE_330 400 0.91 1.98 6 120.88 106.40 TRUE Heskestad < 130 C

E-106 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-2 

Unobstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Heskestad Plume Temperature (Equation 4-3) Data Filtered Filtration Criteria 

BASE_331 500 0.91 1.98 2.4 788.64 1000.00 TRUE Heskestad > 800 C

BASE_331 500 0.91 1.98 2.7 857.78 1000.00 TRUE Heskestad > 800 CBASE_331 500 0.91 1.98 3 859.73 1000.00 TRUE Heskestad > 800 CBASE_331 500 0.91 1.98 3.3 814.29 866.63 TRUE Heskestad > 800 CBASE_331 500 0.91 1.98 3.6 722.21 606.27 FALSE Not FilteredBASE_331 500 0.91 1.98 3.9 590.36 451.82 FALSE Not FilteredBASE_331 500 0.91 1.98 4.2 478.39 351.92 FALSE Not FilteredBASE_331 500 0.91 1.98 4.5 385.71 283.21 FALSE Not FilteredBASE_331 500 0.91 1.98 4.8 308.82 233.69 FALSE Not FilteredBASE_331 500 0.91 1.98 5.1 257.61 196.71 FALSE Not FilteredBASE_331 500 0.91 1.98 5.4 203.98 168.27 FALSE Not FilteredBASE_331 500 0.91 1.98 5.7 161.05 145.89 FALSE Not FilteredBASE_331 500 0.91 1.98 6 135.64 127.92 TRUE Heskestad < 130 CBASE_332 600 0.91 1.98 2.4 805.72 1000.00 TRUE Heskestad > 800 CBASE_332 600 0.91 1.98 2.7 850.96 1000.00 TRUE Heskestad > 800 CBASE_332 600 0.91 1.98 3 885.48 1000.00 TRUE Heskestad > 800 CBASE_332 600 0.91 1.98 3.3 870.38 1000.00 TRUE Heskestad > 800 CBASE_332 600 0.91 1.98 3.6 811.98 744.13 FALSE Not FilteredBASE_332 600 0.91 1.98 3.9 691.37 546.97 FALSE Not FilteredBASE_332 600 0.91 1.98 4.2 589.37 421.86 FALSE Not FilteredBASE_332 600 0.91 1.98 4.5 462.96 336.98 FALSE Not Filtered

E-107 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-2 

Unobstructed Simulation Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Heskestad Plume Temperature (Equation 4-3) Data Filtered Filtration Criteria 

BASE_332 600 0.91 1.98 4.8 366.56 276.46 FALSE Not Filtered

BASE_332 600 0.91 1.98 5.1 290.06 231.64 FALSE Not FilteredBASE_332 600 0.91 1.98 5.4 232.74 197.40 FALSE Not FilteredBASE_332 600 0.91 1.98 5.7 198.21 170.60 FALSE Not FilteredBASE_332 600 0.91 1.98 6 174.61 149.18 FALSE Not Filtered

E-108 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
OBSTRUCTED PLUME FIRE MODELING RESULTS 

E-109 

Determination of Bias and Uncertainty 

Table E-3 

Determination of Bias and Uncertainty 

Test Obstructed FDS Temperature 

(C) 

Heskestad Temperature 

(C) Ln(∆FDS/∆Heskestad) 

ARCH_1055 251.35 772.37  ‐1.12

ARCH_1055 207.5 595.31  ‐1.05

ARCH_1055 181.32 475.29  ‐0.96

ARCH_1055 158.36 389.79  ‐0.90

ARCH_1055 139.08 326.49  ‐0.85

ARCH_1055 123.06 278.17  ‐0.82

ARCH_1056 384.48 729.52  ‐0.64

ARCH_1056 307.37 566.88  ‐0.61

ARCH_1056 259.4 455.37  ‐0.56

ARCH_1056 223.14 375.23  ‐0.52

ARCH_1056 197.29 315.49  ‐0.47

ARCH_1056 177.62 269.64  ‐0.42

ARCH_1056 161.65 233.59  ‐0.37

ARCH_1064 228.02 764.70  ‐1.21

ARCH_1064 180.07 590.25  ‐1.19

ARCH_1064 153.69 471.76  ‐1.12

ARCH_1064 132.29 387.22  ‐1.07

ARCH_1064 119.64 324.55  ‐1.00

ARCH_1065 322.39 722.52  ‐0.81

ARCH_1065 255.39 562.20  ‐0.79

ARCH_1065 208.68 452.07  ‐0.77

ARCH_1065 180.89 372.81  ‐0.72

ARCH_1065 159.61 313.65  ‐0.68

ARCH_1065 138.36 268.21  ‐0.66

ARCH_1065 120.7 232.45  ‐0.66

ARCH_1065 112.26 203.75  ‐0.60

ARCH_830 198.07 402.61  ‐0.71

ARCH_830 112.16 264.28  ‐0.86

ARCH_836 126.04 584.26  ‐1.53

ARCH_837 171.73 619.87  ‐1.28
OBSTRUCTED PLUME FIRE MODELING RESULTS 

E-110 

Table E-3 

Determination of Bias and Uncertainty 

Test Obstructed FDS Temperature 

(C) 

Heskestad Temperature 

(C) Ln(∆FDS/∆Heskestad) 

ARCH_837 118.23 365.81  ‐1.13

ARCH_894 239.92 515.47  ‐0.76

ARCH_894 120.83 354.17  ‐1.08

ARCH_895 172.02 535.11  ‐1.13

ARCH_895 125.64 384.36  ‐1.12

ARCH_896 253.67 735.01  ‐1.06

ARCH_896 172.71 515.78  ‐1.09

ARCH_896 135.45 385.18  ‐1.05

ARCH_896 115.42 300.47  ‐0.96

ARCH_897 255.53 656.81  ‐0.94

ARCH_897 187.46 483.05  ‐0.95

ARCH_897 155.04 372.71  ‐0.88

ARCH_897 131.32 297.80  ‐0.82

ARCH_897 114.1 244.38  ‐0.76

ARCH_898 232 586.29  ‐0.93

ARCH_898 193.7 447.60  ‐0.84

ARCH_898 158.56 354.83  ‐0.81

ARCH_898 134.6 289.41  ‐0.77

ARCH_898 113.8 241.36  ‐0.75

ARCH_901 233.64 748.51  ‐1.16

ARCH_901 174.13 473.69  ‐1.00

ARCH_901 141.03 330.95  ‐0.85

ARCH_901 110.93 246.42  ‐0.80

ARCH_902 325.15 736.43  ‐0.82

ARCH_902 252.2 497.07  ‐0.68

ARCH_902 194.8 361.73  ‐0.62

ARCH_902 158.08 277.01  ‐0.56

ARCH_902 126.34 220.11  ‐0.56

ARCH_903 367.41 678.92  ‐0.61

ARCH_903 269.44 483.57  ‐0.58

ARCH_903 212.59 364.83  ‐0.54
OBSTRUCTED PLUME FIRE MODELING RESULTS 

E-111 

Table E-3 

Determination of Bias and Uncertainty 

Test Obstructed FDS Temperature 

(C) 

Heskestad Temperature 

(C) Ln(∆FDS/∆Heskestad) 

ARCH_903 163.52 286.71  ‐0.56

ARCH_903 137.37 232.29  ‐0.53

ARCH_903 118.3 192.70  ‐0.49

ARCH_904 414.66 613.57  ‐0.39

ARCH_904 314.39 456.37  ‐0.37

ARCH_904 236.69 354.97  ‐0.41

ARCH_904 193.59 285.36  ‐0.39

ARCH_904 162.15 235.27  ‐0.37

ARCH_904 138.1 197.91  ‐0.36

ARCH_904 115.49 169.21  ‐0.38

ARCH_905 513.68 753.25  ‐0.38

ARCH_905 398.77 552.54  ‐0.33

ARCH_905 299.55 425.53  ‐0.35

ARCH_905 243.95 339.54  ‐0.33

ARCH_905 198.04 278.32  ‐0.34

ARCH_905 162.57 233.04  ‐0.36

ARCH_905 134.08 198.49  ‐0.39

ARCH_905 116.82 171.46  ‐0.38

ARCH_958 201.52 528.15  ‐0.96

ARCH_958 115.52 380.26  ‐1.19

ARCH_959 254.49 724.41  ‐1.05

ARCH_959 150.19 509.75  ‐1.22

ARCH_959 115.72 381.39  ‐1.19

ARCH_960 186.86 648.67  ‐1.24

ARCH_960 146.01 478.07  ‐1.19

ARCH_960 117.15 369.41  ‐1.15

ARCH_961 164.16 580.18  ‐1.26

ARCH_961 132.43 443.62  ‐1.21

ARCH_961 113.03 352.09  ‐1.14

ARCH_965 212.09 724.86  ‐1.23

ARCH_965 157.64 490.88  ‐1.14
OBSTRUCTED PLUME FIRE MODELING RESULTS 

E-112 

Table E-3 

Determination of Bias and Uncertainty 

Test Obstructed FDS Temperature 

(C) 

Heskestad Temperature 

(C) Ln(∆FDS/∆Heskestad) 

ARCH_965 126.25 358.00  ‐1.04

ARCH_966 255.26 669.58  ‐0.96

ARCH_966 199.12 478.13  ‐0.88

ARCH_966 160.14 361.36  ‐0.81

ARCH_966 134.08 284.35  ‐0.75

ARCH_966 110.46 230.60  ‐0.74

ARCH_967 232.72 606.27  ‐0.96

ARCH_967 196.54 451.82  ‐0.83

ARCH_967 163.63 351.92  ‐0.77

ARCH_967 133.81 283.21  ‐0.75

ARCH_967 114.52 233.69  ‐0.71

ARCH_968 291.81 744.13  ‐0.94

ARCH_968 225.14 546.97  ‐0.89

ARCH_968 189.01 421.86  ‐0.80

ARCH_968 153.48 336.98  ‐0.79

ARCH_968 129.83 276.46  ‐0.76

ARCH_968 111.62 231.64  ‐0.73

OBST_1052 360.12 772.37  ‐0.76

OBST_1052 318.6 595.31  ‐0.63

OBST_1052 299.22 475.29  ‐0.46

OBST_1052 286.21 389.79  ‐0.31

OBST_1052 268.02 326.49  ‐0.20

OBST_1052 250.8 278.17  ‐0.10

OBST_1052 235.33 240.36  ‐0.02

OBST_1052 216.32 210.14 0.03

OBST_1052 199.16 185.58 0.07

OBST_1052 184.84 165.31 0.11

OBST_1053 514.31 729.52  ‐0.35

OBST_1053 450.83 566.88  ‐0.23

OBST_1053 404.86 455.37  ‐0.12

OBST_1053 362.82 375.23  ‐0.03
OBSTRUCTED PLUME FIRE MODELING RESULTS 

E-113 

Table E-3 

Determination of Bias and Uncertainty 

Test Obstructed FDS Temperature 

(C) 

Heskestad Temperature 

(C) Ln(∆FDS/∆Heskestad) 

OBST_1053 313 315.49  ‐0.01

OBST_1053 273.13 269.64 0.01

OBST_1053 238.54 233.59 0.02

OBST_1061 376.9 764.70  ‐0.71

OBST_1061 300.69 590.25  ‐0.67

OBST_1061 259.7 471.76  ‐0.60

OBST_1061 235.99 387.22  ‐0.50

OBST_1061 219.89 324.55  ‐0.39

OBST_1061 206.26 276.67  ‐0.29

OBST_1061 196.94 239.17  ‐0.19

OBST_1061 187.38 209.19  ‐0.11

OBST_1061 176.74 184.79  ‐0.04

OBST_1061 164 164.65 0.00

OBST_1061 152.26 147.81 0.03

OBST_1062 474.5 722.52  ‐0.42

OBST_1062 426.72 562.20  ‐0.28

OBST_1062 385.71 452.07  ‐0.16

OBST_1062 347.67 372.81  ‐0.07

OBST_1062 313.88 313.65 0.00

OBST_1062 275.56 268.21 0.03

OBST_1062 239.91 232.45 0.03

OBST_1062 213 203.75 0.04

OBST_808 118.47 209.49  ‐0.57

OBST_809 215.87 402.61  ‐0.62

OBST_809 135.85 264.28  ‐0.67

OBST_815 122.51 584.26  ‐1.56

OBST_816 150.7 619.87  ‐1.41

OBST_816 125.87 365.81  ‐1.07

OBST_816 110.11 245.21  ‐0.80

OBST_873 232.79 515.47  ‐0.79

OBST_873 158.78 354.17  ‐0.80
OBSTRUCTED PLUME FIRE MODELING RESULTS 

E-114 

Table E-3 

Determination of Bias and Uncertainty 

Test Obstructed FDS Temperature 

(C) 

Heskestad Temperature 

(C) Ln(∆FDS/∆Heskestad) 

OBST_873 119.76 260.78  ‐0.78

OBST_874 225.86 535.11  ‐0.86

OBST_874 164.52 384.36  ‐0.85

OBST_874 136.76 291.68  ‐0.76

OBST_874 126.93 230.20  ‐0.60

OBST_874 121.51 187.12  ‐0.43

OBST_874 116.21 155.63  ‐0.29

OBST_875 331.26 735.01  ‐0.80

OBST_875 234.18 515.78  ‐0.79

OBST_875 181.11 385.18  ‐0.75

OBST_875 168.81 300.47  ‐0.58

OBST_875 157.84 242.07  ‐0.43

OBST_875 149.98 199.93  ‐0.29

OBST_875 142.77 168.41  ‐0.17

OBST_875 134.43 144.15  ‐0.07

OBST_875 126.06 125.03 0.01

OBST_876 305.36 656.81  ‐0.77

OBST_876 226.23 483.05  ‐0.76

OBST_876 210.64 372.71  ‐0.57

OBST_876 200.37 297.80  ‐0.40

OBST_876 189.08 244.38  ‐0.26

OBST_876 176.49 204.79  ‐0.15

OBST_876 165.18 174.55  ‐0.06

OBST_876 154.3 150.87 0.02

OBST_876 142.71 131.94 0.08

OBST_876 130.55 116.55 0.11

OBST_877 279.89 586.29  ‐0.74

OBST_877 247.2 447.60  ‐0.59

OBST_877 232.02 354.83  ‐0.42

OBST_877 218.02 289.41  ‐0.28

OBST_877 200.1 241.36  ‐0.19
OBSTRUCTED PLUME FIRE MODELING RESULTS 

E-115 

Table E-3 

Determination of Bias and Uncertainty 

Test Obstructed FDS Temperature 

(C) 

Heskestad Temperature 

(C) Ln(∆FDS/∆Heskestad) 

OBST_877 186.1 204.91  ‐0.10

OBST_877 174.77 176.53  ‐0.01

OBST_877 163.24 153.95 0.06

OBST_877 150.25 135.67 0.10

OBST_877 137.23 120.63 0.13

OBST_880 261.92 748.51  ‐1.05

OBST_880 186.03 473.69  ‐0.93

OBST_880 143.97 330.95  ‐0.83

OBST_880 115.19 246.42  ‐0.76

OBST_881 253.32 736.43  ‐1.07

OBST_881 214.24 497.07  ‐0.84

OBST_881 193.54 361.73  ‐0.63

OBST_881 179.06 277.01  ‐0.44

OBST_881 159.94 220.11  ‐0.32

OBST_881 145.89 179.84  ‐0.21

OBST_881 133.19 150.19  ‐0.12

OBST_881 118.07 127.65  ‐0.08

OBST_882 336 678.92  ‐0.70

OBST_882 295.04 483.57  ‐0.49

OBST_882 265.76 364.83  ‐0.32

OBST_882 233.9 286.71  ‐0.20

OBST_882 203.38 232.29  ‐0.13

OBST_882 180.05 192.70  ‐0.07

OBST_882 155.4 162.90  ‐0.05

OBST_882 134.3 139.84  ‐0.04

OBST_882 119.3 121.60  ‐0.02

OBST_883 376.41 613.57  ‐0.49

OBST_883 329.43 456.37  ‐0.33

OBST_883 285.67 354.97  ‐0.22

OBST_883 252.27 285.36  ‐0.12

OBST_883 227.61 235.27  ‐0.03
OBSTRUCTED PLUME FIRE MODELING RESULTS 

E-116 

Table E-3 

Determination of Bias and Uncertainty 

Test Obstructed FDS Temperature 

(C) 

Heskestad Temperature 

(C) Ln(∆FDS/∆Heskestad) 

OBST_883 200 197.91 0.01

OBST_883 174.5 169.21 0.03

OBST_883 155.45 146.63 0.06

OBST_884 480.69 753.25  ‐0.45

OBST_884 428.14 552.54  ‐0.26

OBST_884 374.23 425.53  ‐0.13

OBST_884 327.72 339.54  ‐0.04

OBST_884 284.84 278.32 0.02

OBST_884 242.25 233.04 0.04

OBST_884 210.22 198.49 0.06

OBST_884 186.23 171.46 0.08

OBST_937 236.44 528.15  ‐0.80

OBST_937 170.78 380.26  ‐0.80

OBST_937 126.6 289.03  ‐0.83

OBST_938 325.72 724.41  ‐0.80

OBST_938 212.8 509.75  ‐0.87

OBST_938 162.85 381.39  ‐0.85

OBST_938 136.65 297.92  ‐0.78

OBST_938 127.22 240.27  ‐0.64

OBST_938 121.22 198.60  ‐0.49

OBST_938 116.82 167.40  ‐0.36

OBST_938 110.48 143.36  ‐0.26

OBST_939 285.96 648.67  ‐0.82

OBST_939 204.42 478.07  ‐0.85

OBST_939 166.46 369.41  ‐0.80

OBST_939 156.39 295.50  ‐0.64

OBST_939 149.66 242.70  ‐0.48

OBST_939 144.02 203.52  ‐0.35

OBST_939 136.28 173.57  ‐0.24

OBST_939 129.36 150.10  ‐0.15

OBST_939 121.6 131.32  ‐0.08
OBSTRUCTED PLUME FIRE MODELING RESULTS 

E-117 

Table E-3 

Determination of Bias and Uncertainty 

Test Obstructed FDS Temperature 

(C) 

Heskestad Temperature 

(C) Ln(∆FDS/∆Heskestad) 

OBST_939 112.1 116.03  ‐0.03

OBST_940 272.81 580.18  ‐0.75

OBST_940 220.08 443.62  ‐0.70

OBST_940 194.75 352.09  ‐0.59

OBST_940 176.25 287.43  ‐0.49

OBST_940 167.07 239.87  ‐0.36

OBST_940 159.33 203.76  ‐0.25

OBST_940 152.41 175.63  ‐0.14

OBST_940 145.68 153.23  ‐0.05

OBST_940 136.24 135.08 0.01

OBST_940 125.56 120.14 0.04

OBST_944 210.14 724.86  ‐1.24

OBST_944 178.17 490.88  ‐1.01

OBST_944 170.23 358.00  ‐0.74

OBST_944 162.18 274.58  ‐0.53

OBST_944 152.71 218.42  ‐0.36

OBST_944 141.02 178.62  ‐0.24

OBST_944 130.26 149.28  ‐0.14

OBST_944 119.52 126.95  ‐0.06

OBST_945 251.01 669.58  ‐0.98

OBST_945 236.39 478.13  ‐0.70

OBST_945 222.45 361.36  ‐0.49

OBST_945 204.26 284.35  ‐0.33

OBST_945 182.73 230.60  ‐0.23

OBST_945 165.73 191.45  ‐0.14

OBST_945 149.17 161.94  ‐0.08

OBST_945 131.88 139.09  ‐0.05

OBST_945 115.11 121.00  ‐0.05

OBST_946 303.72 606.27  ‐0.69

OBST_946 282.66 451.82  ‐0.47

OBST_946 260.58 351.92  ‐0.30
OBSTRUCTED PLUME FIRE MODELING RESULTS 

E-118 

Table E-3 

Determination of Bias and Uncertainty 

Test Obstructed FDS Temperature 

(C) 

Heskestad Temperature 

(C) Ln(∆FDS/∆Heskestad) 

OBST_946 235.83 283.21  ‐0.18

OBST_946 213.31 233.69  ‐0.09

OBST_946 190.86 196.71  ‐0.03

OBST_946 168.4 168.27 0.00

OBST_946 145.77 145.89 0.00

OBST_946 130.43 127.92 0.02

OBST_947 390.02 744.13  ‐0.65

OBST_947 351.04 546.97  ‐0.44

OBST_947 318.75 421.86  ‐0.28

OBST_947 279.61 336.98  ‐0.19

OBST_947 246.02 276.46  ‐0.12

OBST_947 217.54 231.64  ‐0.06

OBST_947 189.53 197.40  ‐0.04

OBST_947 164.54 170.60  ‐0.04

OBST_947 147.13 149.18  ‐0.01

THREEWALL_1058 381.71 772.37  ‐0.70

THREEWALL_1058 319.8 595.31  ‐0.62

THREEWALL_1058 264.72 475.29  ‐0.59

THREEWALL_1058 230.82 389.79  ‐0.52

THREEWALL_1058 195.58 326.49  ‐0.51

THREEWALL_1058 168.42 278.17  ‐0.50

THREEWALL_1058 146.49 240.36  ‐0.50

THREEWALL_1058 126.15 210.14  ‐0.51

THREEWALL_1058 115.05 185.58  ‐0.48

THREEWALL_1059 527.72 729.52  ‐0.32

THREEWALL_1059 411.6 566.88  ‐0.32

THREEWALL_1059 334.89 455.37  ‐0.31

THREEWALL_1059 286.67 375.23  ‐0.27

THREEWALL_1059 244.2 315.49  ‐0.26

THREEWALL_1059 207.16 269.64  ‐0.26

THREEWALL_1059 186.73 233.59  ‐0.22
OBSTRUCTED PLUME FIRE MODELING RESULTS 

E-119 

Table E-3 

Determination of Bias and Uncertainty 

Test Obstructed FDS Temperature 

(C) 

Heskestad Temperature 

(C) Ln(∆FDS/∆Heskestad) 

THREEWALL_1067 343.31 764.70  ‐0.80

THREEWALL_1067 279.81 590.25  ‐0.75

THREEWALL_1067 235.01 471.76  ‐0.70

THREEWALL_1067 190.95 387.22  ‐0.71

THREEWALL_1067 167.89 324.55  ‐0.66

THREEWALL_1067 141.24 276.67  ‐0.67

THREEWALL_1067 125.62 239.17  ‐0.64

THREEWALL_1067 112.94 209.19  ‐0.62

THREEWALL_1068 496.14 722.52  ‐0.38

THREEWALL_1068 397.07 562.20  ‐0.35

THREEWALL_1068 318.85 452.07  ‐0.35

THREEWALL_1068 272.29 372.81  ‐0.31

THREEWALL_1068 234.15 313.65  ‐0.29

THREEWALL_1068 204.04 268.21  ‐0.27

THREEWALL_1068 179.74 232.45  ‐0.26

THREEWALL_1068 161.86 203.75  ‐0.23

THREEWALL_850 155.3 209.49  ‐0.30

THREEWALL_851 255.53 402.61  ‐0.45

THREEWALL_851 139.25 264.28  ‐0.64

THREEWALL_857 235.48 584.26  ‐0.91

THREEWALL_857 157.34 306.03  ‐0.67

THREEWALL_857 111.29 192.28  ‐0.55

THREEWALL_858 327.37 619.87  ‐0.64

THREEWALL_858 218.83 365.81  ‐0.51

THREEWALL_858 169.87 245.21  ‐0.37

THREEWALL_858 135.33 177.64  ‐0.27

THREEWALL_915 300.06 515.47  ‐0.54

THREEWALL_915 159.86 354.17  ‐0.80

THREEWALL_915 134.36 260.78  ‐0.66

THREEWALL_916 250.02 535.11  ‐0.76

THREEWALL_916 174.28 384.36  ‐0.79
OBSTRUCTED PLUME FIRE MODELING RESULTS 

E-120 

Table E-3 

Determination of Bias and Uncertainty 

Test Obstructed FDS Temperature 

(C) 

Heskestad Temperature 

(C) Ln(∆FDS/∆Heskestad) 

THREEWALL_916 141.38 291.68  ‐0.72

THREEWALL_916 123.99 230.20  ‐0.62

THREEWALL_916 110.29 187.12  ‐0.53

THREEWALL_917 370.31 735.01  ‐0.69

THREEWALL_917 250.68 515.78  ‐0.72

THREEWALL_917 183.21 385.18  ‐0.74

THREEWALL_917 152.33 300.47  ‐0.68

THREEWALL_917 132.92 242.07  ‐0.60

THREEWALL_917 118.8 199.93  ‐0.52

THREEWALL_918 313.59 656.81  ‐0.74

THREEWALL_918 222.06 483.05  ‐0.78

THREEWALL_918 184.52 372.71  ‐0.70

THREEWALL_918 155.58 297.80  ‐0.65

THREEWALL_918 134.38 244.38  ‐0.60

THREEWALL_918 110.96 204.79  ‐0.61

THREEWALL_919 305.81 586.29  ‐0.65

THREEWALL_919 248 447.60  ‐0.59

THREEWALL_919 203.92 354.83  ‐0.55

THREEWALL_919 176.1 289.41  ‐0.50

THREEWALL_919 152.14 241.36  ‐0.46

THREEWALL_919 138.53 204.91  ‐0.39

THREEWALL_919 123.64 176.53  ‐0.36

THREEWALL_922 418.25 748.51  ‐0.58

THREEWALL_922 309.14 473.69  ‐0.43

THREEWALL_922 236.87 330.95  ‐0.33

THREEWALL_922 183.85 246.42  ‐0.29

THREEWALL_922 148.83 191.81  ‐0.25

THREEWALL_922 125.65 154.28  ‐0.21

THREEWALL_923 490.62 736.43  ‐0.41

THREEWALL_923 368.3 497.07  ‐0.30

THREEWALL_923 270.83 361.73  ‐0.29
OBSTRUCTED PLUME FIRE MODELING RESULTS 

E-121 

Table E-3 

Determination of Bias and Uncertainty 

Test Obstructed FDS Temperature 

(C) 

Heskestad Temperature 

(C) Ln(∆FDS/∆Heskestad) 

THREEWALL_923 210.29 277.01  ‐0.28

THREEWALL_923 162.55 220.11  ‐0.30

THREEWALL_923 137.83 179.84  ‐0.27

THREEWALL_923 120.83 150.19  ‐0.22

THREEWALL_924 499.42 678.92  ‐0.31

THREEWALL_924 368.24 483.57  ‐0.27

THREEWALL_924 286.26 364.83  ‐0.24

THREEWALL_924 226.33 286.71  ‐0.24

THREEWALL_924 193.8 232.29  ‐0.18

THREEWALL_924 163.16 192.70  ‐0.17

THREEWALL_924 137.27 162.90  ‐0.17

THREEWALL_924 117.47 139.84  ‐0.17

THREEWALL_925 498.6 613.57  ‐0.21

THREEWALL_925 385.1 456.37  ‐0.17

THREEWALL_925 290.44 354.97  ‐0.20

THREEWALL_925 242.34 285.36  ‐0.16

THREEWALL_925 201.57 235.27  ‐0.15

THREEWALL_925 172.52 197.91  ‐0.14

THREEWALL_925 146.57 169.21  ‐0.14

THREEWALL_925 126.18 146.63  ‐0.15

THREEWALL_926 541.53 753.25  ‐0.33

THREEWALL_926 420.71 552.54  ‐0.27

THREEWALL_926 320.56 425.53  ‐0.28

THREEWALL_926 264.69 339.54  ‐0.25

THREEWALL_926 224.92 278.32  ‐0.21

THREEWALL_926 188.27 233.04  ‐0.21

THREEWALL_926 163.19 198.49  ‐0.20

THREEWALL_926 146.48 171.46  ‐0.16

THREEWALL_979 290.52 528.15  ‐0.60

THREEWALL_979 164.64 380.26  ‐0.84

THREEWALL_979 126.48 289.03  ‐0.83
OBSTRUCTED PLUME FIRE MODELING RESULTS 

E-122 

Table E-3 

Determination of Bias and Uncertainty 

Test Obstructed FDS Temperature 

(C) 

Heskestad Temperature 

(C) Ln(∆FDS/∆Heskestad) 

THREEWALL_980 360.97 724.41  ‐0.70

THREEWALL_980 211.62 509.75  ‐0.88

THREEWALL_980 164.42 381.39  ‐0.84

THREEWALL_980 131.59 297.92  ‐0.82

THREEWALL_980 114.53 240.27  ‐0.74

THREEWALL_981 263.14 648.67  ‐0.90

THREEWALL_981 203.96 478.07  ‐0.85

THREEWALL_981 167.48 369.41  ‐0.79

THREEWALL_981 143.06 295.50  ‐0.73

THREEWALL_981 126.31 242.70  ‐0.65

THREEWALL_981 113.8 203.52  ‐0.58

THREEWALL_982 248.81 580.18  ‐0.85

THREEWALL_982 201.1 443.62  ‐0.79

THREEWALL_982 173.38 352.09  ‐0.71

THREEWALL_982 151.54 287.43  ‐0.64

THREEWALL_982 133.52 239.87  ‐0.59

THREEWALL_982 118.27 203.76  ‐0.54

THREEWALL_986 470.11 724.86  ‐0.43

THREEWALL_986 333.3 490.88  ‐0.39

THREEWALL_986 258.73 358.00  ‐0.32

THREEWALL_986 207.21 274.58  ‐0.28

THREEWALL_986 162.1 218.42  ‐0.30

THREEWALL_986 128.46 178.62  ‐0.33

THREEWALL_987 421.27 669.58  ‐0.46

THREEWALL_987 319.87 478.13  ‐0.40

THREEWALL_987 246.42 361.36  ‐0.38

THREEWALL_987 200.39 284.35  ‐0.35

THREEWALL_987 162.32 230.60  ‐0.35

THREEWALL_987 144.19 191.45  ‐0.28

THREEWALL_987 128.53 161.94  ‐0.23

THREEWALL_987 115.35 139.09  ‐0.19
OBSTRUCTED PLUME FIRE MODELING RESULTS 

E-123 

Table E-3 

Determination of Bias and Uncertainty 

Test Obstructed FDS Temperature 

(C) 

Heskestad Temperature 

(C) Ln(∆FDS/∆Heskestad) 

THREEWALL_988 434.55 606.27  ‐0.33

THREEWALL_988 323.91 451.82  ‐0.33

THREEWALL_988 262.91 351.92  ‐0.29

THREEWALL_988 209.44 283.21  ‐0.30

THREEWALL_988 178.62 233.69  ‐0.27

THREEWALL_988 157.02 196.71  ‐0.23

THREEWALL_988 137.24 168.27  ‐0.20

THREEWALL_988 117.4 145.89  ‐0.22

THREEWALL_989 562.49 744.13  ‐0.28

THREEWALL_989 411.65 546.97  ‐0.28

THREEWALL_989 329.02 421.86  ‐0.25

THREEWALL_989 250.92 336.98  ‐0.29

THREEWALL_989 213.27 276.46  ‐0.26

THREEWALL_989 182.93 231.64  ‐0.24

THREEWALL_989 156.71 197.40  ‐0.23

THREEWALL_989 131.1 170.60  ‐0.26

THREEWALL_989 117.61 149.18  ‐0.24

USING EQUATIONS FROM SECTION 5.2.4.5 

ln ቀெ

ாቁ തതതതതതതത ൌ ଵ௡ ∑ ln ቀெ೔

ா೔

ቁ ௡

௜ୀଵ ൌ 	 െ0.50 (5-11) 

ெ෤ߪ

ଶ ൅ ߪ෤ாଶ ൌ ଵ

ଵି௡ ∑ ቂln ቀெ೔

ா೔

ቁ െ ln ቀெ

ாቁ തതതതതതതത

ቃ

ଶ

௡

௜ୀଵ ൌ 0.11 (5-12) 

ߪ෤ா ൌ 0.20

ߪ෤ெ ൌ 0.28

ߜ ൌ expቀln ቀ

ெ

ாቁ തതതതതതതത ൅ ఙ෥ಾ

మ

ଶ െ ఙ෥ಶ

మ

ଶ ቁ ൌ 0.62 (5-13) 
Opening Sensitivity Cases 

Table E-4 

Opening Sensitivity Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Opening Percentage 

ARCH_1101 200 0.61 1.98 2.4 937.56 6

ARCH_1101 200 0.61 1.98 2.7 804.3 6ARCH_1101 200 0.61 1.98 3 530.41 6ARCH_1101 200 0.61 1.98 3.3 327 6ARCH_1101 200 0.61 1.98 3.6 228.87 6ARCH_1101 200 0.61 1.98 3.9 164.39 6ARCH_1101 200 0.61 1.98 4.2 128.92 6ARCH_1101 200 0.61 1.98 4.5 103.83 6ARCH_1101 200 0.61 1.98 4.8 89.37 6ARCH_1101 200 0.61 1.98 5.1 79.014 6ARCH_1101 200 0.61 1.98 5.4 70.186 6ARCH_1101 200 0.61 1.98 5.7 63.806 6ARCH_1101 200 0.61 1.98 6 57.845 6ARCH_1104 200 0.61 1.98 2.4 938.78 10ARCH_1104 200 0.61 1.98 2.7 797.27 10ARCH_1104 200 0.61 1.98 3 538.71 10ARCH_1104 200 0.61 1.98 3.3 306.25 10ARCH_1104 200 0.61 1.98 3.6 219.26 10ARCH_1104 200 0.61 1.98 3.9 172.2 10ARCH_1104 200 0.61 1.98 4.2 143.44 10ARCH_1104 200 0.61 1.98 4.5 117.38 10

E-124 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-4 

Opening Sensitivity Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Opening Percentage 

ARCH_1104 200 0.61 1.98 4.8 103.22 10

ARCH_1104 200 0.61 1.98 5.1 91.39 10ARCH_1104 200 0.61 1.98 5.4 78.053 10ARCH_1104 200 0.61 1.98 5.7 69.999 10ARCH_1104 200 0.61 1.98 6 66.112 10ARCH_1107 200 0.61 1.98 2.4 936.64 14ARCH_1107 200 0.61 1.98 2.7 809.41 14ARCH_1107 200 0.61 1.98 3 558.92 14ARCH_1107 200 0.61 1.98 3.3 338.16 14ARCH_1107 200 0.61 1.98 3.6 250.38 14ARCH_1107 200 0.61 1.98 3.9 186.33 14ARCH_1107 200 0.61 1.98 4.2 148.42 14ARCH_1107 200 0.61 1.98 4.5 124.24 14ARCH_1107 200 0.61 1.98 4.8 107.65 14ARCH_1107 200 0.61 1.98 5.1 93.37 14ARCH_1107 200 0.61 1.98 5.4 80.35 14ARCH_1107 200 0.61 1.98 5.7 69.691 14ARCH_1107 200 0.61 1.98 6 60.263 14ARCH_1110 600 0.91 1.98 2.4 864.32 7ARCH_1110 600 0.91 1.98 2.7 811.89 7ARCH_1110 600 0.91 1.98 3 712.42 7ARCH_1110 600 0.91 1.98 3.3 619.63 7

E-125 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-4 

Opening Sensitivity Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Opening Percentage 

ARCH_1110 600 0.91 1.98 3.6 537.1 7

ARCH_1110 600 0.91 1.98 3.9 410.59 7ARCH_1110 600 0.91 1.98 4.2 313.78 7ARCH_1110 600 0.91 1.98 4.5 239.77 7ARCH_1110 600 0.91 1.98 4.8 192.91 7ARCH_1110 600 0.91 1.98 5.1 170.72 7ARCH_1110 600 0.91 1.98 5.4 149.15 7ARCH_1110 600 0.91 1.98 5.7 135.01 7ARCH_1110 600 0.91 1.98 6 121.85 7ARCH_1113 600 0.91 1.98 2.4 935.11 10ARCH_1113 600 0.91 1.98 2.7 879.75 10ARCH_1113 600 0.91 1.98 3 808.18 10ARCH_1113 600 0.91 1.98 3.3 684.08 10ARCH_1113 600 0.91 1.98 3.6 597.73 10ARCH_1113 600 0.91 1.98 3.9 456.27 10ARCH_1113 600 0.91 1.98 4.2 367.47 10ARCH_1113 600 0.91 1.98 4.5 297.95 10ARCH_1113 600 0.91 1.98 4.8 245.22 10ARCH_1113 600 0.91 1.98 5.1 199.07 10ARCH_1113 600 0.91 1.98 5.4 168.48 10ARCH_1113 600 0.91 1.98 5.7 146.04 10ARCH_1113 600 0.91 1.98 6 128.03 10

E-126 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-4 

Opening Sensitivity Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Opening Percentage 

ARCH_1116 600 0.91 1.98 2.4 938.2 12

ARCH_1116 600 0.91 1.98 2.7 893.53 12ARCH_1116 600 0.91 1.98 3 792.6 12ARCH_1116 600 0.91 1.98 3.3 662.2 12ARCH_1116 600 0.91 1.98 3.6 551 12ARCH_1116 600 0.91 1.98 3.9 440.94 12ARCH_1116 600 0.91 1.98 4.2 332.47 12ARCH_1116 600 0.91 1.98 4.5 261.76 12ARCH_1116 600 0.91 1.98 4.8 232.45 12ARCH_1116 600 0.91 1.98 5.1 190.96 12ARCH_1116 600 0.91 1.98 5.4 158.47 12ARCH_1116 600 0.91 1.98 5.7 141.04 12ARCH_1116 600 0.91 1.98 6 123.93 12

OBST_1100 200 0.61 1.98 2.4 901.43 6OBST_1100 200 0.61 1.98 2.7 602.1 6OBST_1100 200 0.61 1.98 3 389.92 6OBST_1100 200 0.61 1.98 3.3 270.13 6OBST_1100 200 0.61 1.98 3.6 216.79 6OBST_1100 200 0.61 1.98 3.9 177.04 6OBST_1100 200 0.61 1.98 4.2 151.64 6OBST_1100 200 0.61 1.98 4.5 127.06 6OBST_1100 200 0.61 1.98 4.8 109.56 6

E-127 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-4 

Opening Sensitivity Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Opening Percentage 

OBST_1100 200 0.61 1.98 5.1 96.42 6

OBST_1100 200 0.61 1.98 5.4 85.68 6OBST_1100 200 0.61 1.98 5.7 76.722 6OBST_1100 200 0.61 1.98 6 69.612 6OBST_1103 200 0.61 1.98 2.4 965.45 10OBST_1103 200 0.61 1.98 2.7 768.83 10OBST_1103 200 0.61 1.98 3 559.68 10OBST_1103 200 0.61 1.98 3.3 391 10OBST_1103 200 0.61 1.98 3.6 297.69 10OBST_1103 200 0.61 1.98 3.9 228.19 10OBST_1103 200 0.61 1.98 4.2 187.49 10OBST_1103 200 0.61 1.98 4.5 152.8 10OBST_1103 200 0.61 1.98 4.8 133.98 10OBST_1103 200 0.61 1.98 5.1 115.76 10OBST_1103 200 0.61 1.98 5.4 98.46 10OBST_1103 200 0.61 1.98 5.7 85.02 10OBST_1103 200 0.61 1.98 6 75.158 10OBST_1106 200 0.61 1.98 2.4 918.35 14OBST_1106 200 0.61 1.98 2.7 728.72 14OBST_1106 200 0.61 1.98 3 533.61 14OBST_1106 200 0.61 1.98 3.3 370.73 14OBST_1106 200 0.61 1.98 3.6 286.68 14

E-128 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-4 

Opening Sensitivity Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Opening Percentage 

OBST_1106 200 0.61 1.98 3.9 217.32 14

OBST_1106 200 0.61 1.98 4.2 172.61 14OBST_1106 200 0.61 1.98 4.5 136.16 14OBST_1106 200 0.61 1.98 4.8 111.35 14OBST_1106 200 0.61 1.98 5.1 95.45 14OBST_1106 200 0.61 1.98 5.4 82.94 14OBST_1106 200 0.61 1.98 5.7 73.083 14OBST_1106 200 0.61 1.98 6 67.295 14OBST_1109 600 0.91 1.98 2.4 854.62 7OBST_1109 600 0.91 1.98 2.7 849.81 7OBST_1109 600 0.91 1.98 3 785.25 7OBST_1109 600 0.91 1.98 3.3 695.57 7OBST_1109 600 0.91 1.98 3.6 592.45 7OBST_1109 600 0.91 1.98 3.9 473.33 7OBST_1109 600 0.91 1.98 4.2 390.05 7OBST_1109 600 0.91 1.98 4.5 318.33 7OBST_1109 600 0.91 1.98 4.8 274 7OBST_1109 600 0.91 1.98 5.1 239.74 7OBST_1109 600 0.91 1.98 5.4 204.37 7OBST_1109 600 0.91 1.98 5.7 175.5 7OBST_1109 600 0.91 1.98 6 151.72 7OBST_1112 600 0.91 1.98 2.4 923.28 10

E-129 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-4 

Opening Sensitivity Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Opening Percentage 

OBST_1112 600 0.91 1.98 2.7 915.92 10

OBST_1112 600 0.91 1.98 3 864.74 10OBST_1112 600 0.91 1.98 3.3 774.66 10OBST_1112 600 0.91 1.98 3.6 662.67 10OBST_1112 600 0.91 1.98 3.9 565.45 10OBST_1112 600 0.91 1.98 4.2 481.41 10OBST_1112 600 0.91 1.98 4.5 382.74 10OBST_1112 600 0.91 1.98 4.8 316 10OBST_1112 600 0.91 1.98 5.1 262.73 10OBST_1112 600 0.91 1.98 5.4 216.83 10OBST_1112 600 0.91 1.98 5.7 183.67 10OBST_1112 600 0.91 1.98 6 160.17 10OBST_1115 600 0.91 1.98 2.4 951.08 12OBST_1115 600 0.91 1.98 2.7 897.98 12OBST_1115 600 0.91 1.98 3 892.86 12OBST_1115 600 0.91 1.98 3.3 794.16 12OBST_1115 600 0.91 1.98 3.6 690.03 12OBST_1115 600 0.91 1.98 3.9 577.49 12OBST_1115 600 0.91 1.98 4.2 458.86 12OBST_1115 600 0.91 1.98 4.5 368.8 12OBST_1115 600 0.91 1.98 4.8 307.16 12OBST_1115 600 0.91 1.98 5.1 253.02 12

E-130 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-4 

Opening Sensitivity Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Opening Percentage 

OBST_1115 600 0.91 1.98 5.4 212.6 12

OBST_1115 600 0.91 1.98 5.7 177.64 12OBST_1115 600 0.91 1.98 6 157.52 12

THREEWALL_1102 200 0.61 1.98 2.4 948.99 6THREEWALL_1102 200 0.61 1.98 2.7 824.5 6THREEWALL_1102 200 0.61 1.98 3 625.36 6THREEWALL_1102 200 0.61 1.98 3.3 381.42 6THREEWALL_1102 200 0.61 1.98 3.6 255.08 6THREEWALL_1102 200 0.61 1.98 3.9 178.07 6THREEWALL_1102 200 0.61 1.98 4.2 135.23 6THREEWALL_1102 200 0.61 1.98 4.5 106.91 6THREEWALL_1102 200 0.61 1.98 4.8 90.78 6THREEWALL_1102 200 0.61 1.98 5.1 78.946 6THREEWALL_1102 200 0.61 1.98 5.4 70.587 6THREEWALL_1102 200 0.61 1.98 5.7 60.087 6THREEWALL_1102 200 0.61 1.98 6 53.403 6THREEWALL_1105 200 0.61 1.98 2.4 955.95 10THREEWALL_1105 200 0.61 1.98 2.7 780.37 10THREEWALL_1105 200 0.61 1.98 3 569.42 10THREEWALL_1105 200 0.61 1.98 3.3 358.73 10THREEWALL_1105 200 0.61 1.98 3.6 252.27 10THREEWALL_1105 200 0.61 1.98 3.9 177.91 10

E-131 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-4 

Opening Sensitivity Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Opening Percentage 

THREEWALL_1105 200 0.61 1.98 4.2 136.88 10

THREEWALL_1105 200 0.61 1.98 4.5 113.62 10THREEWALL_1105 200 0.61 1.98 4.8 94.94 10THREEWALL_1105 200 0.61 1.98 5.1 81.84 10THREEWALL_1105 200 0.61 1.98 5.4 71.209 10THREEWALL_1105 200 0.61 1.98 5.7 63.762 10THREEWALL_1105 200 0.61 1.98 6 57.409 10THREEWALL_1108 200 0.61 1.98 2.4 928.8 14THREEWALL_1108 200 0.61 1.98 2.7 751.6 14THREEWALL_1108 200 0.61 1.98 3 583.09 14THREEWALL_1108 200 0.61 1.98 3.3 395.52 14THREEWALL_1108 200 0.61 1.98 3.6 280.94 14THREEWALL_1108 200 0.61 1.98 3.9 203.94 14THREEWALL_1108 200 0.61 1.98 4.2 160.04 14THREEWALL_1108 200 0.61 1.98 4.5 128.85 14THREEWALL_1108 200 0.61 1.98 4.8 112.91 14THREEWALL_1108 200 0.61 1.98 5.1 97.66 14THREEWALL_1108 200 0.61 1.98 5.4 85.96 14THREEWALL_1108 200 0.61 1.98 5.7 71.963 14THREEWALL_1108 200 0.61 1.98 6 64.651 14THREEWALL_1111 600 0.91 1.98 2.4 792.68 7THREEWALL_1111 600 0.91 1.98 2.7 782.33 7

E-132 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-4 

Opening Sensitivity Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Opening Percentage 

THREEWALL_1111 600 0.91 1.98 3 806.99 7

THREEWALL_1111 600 0.91 1.98 3.3 686.87 7THREEWALL_1111 600 0.91 1.98 3.6 597.97 7THREEWALL_1111 600 0.91 1.98 3.9 461.87 7THREEWALL_1111 600 0.91 1.98 4.2 344.28 7THREEWALL_1111 600 0.91 1.98 4.5 260.38 7THREEWALL_1111 600 0.91 1.98 4.8 221.84 7THREEWALL_1111 600 0.91 1.98 5.1 188.45 7THREEWALL_1111 600 0.91 1.98 5.4 164.6 7THREEWALL_1111 600 0.91 1.98 5.7 144.27 7THREEWALL_1111 600 0.91 1.98 6 129.47 7THREEWALL_1114 600 0.91 1.98 2.4 911.41 10THREEWALL_1114 600 0.91 1.98 2.7 869.36 10THREEWALL_1114 600 0.91 1.98 3 834.75 10THREEWALL_1114 600 0.91 1.98 3.3 702.84 10THREEWALL_1114 600 0.91 1.98 3.6 591.34 10THREEWALL_1114 600 0.91 1.98 3.9 464.06 10THREEWALL_1114 600 0.91 1.98 4.2 370.37 10THREEWALL_1114 600 0.91 1.98 4.5 300.22 10THREEWALL_1114 600 0.91 1.98 4.8 243.72 10THREEWALL_1114 600 0.91 1.98 5.1 206.52 10THREEWALL_1114 600 0.91 1.98 5.4 172.52 10

E-133 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-4 

Opening Sensitivity Results 

Test HRR (kW) Diameter (m) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Opening Percentage 

THREEWALL_1114 600 0.91 1.98 5.7 151.32 10

THREEWALL_1114 600 0.91 1.98 6 136.66 10THREEWALL_1117 600 0.91 1.98 2.4 905 12THREEWALL_1117 600 0.91 1.98 2.7 892.38 12THREEWALL_1117 600 0.91 1.98 3 865.65 12THREEWALL_1117 600 0.91 1.98 3.3 722.89 12THREEWALL_1117 600 0.91 1.98 3.6 603.73 12THREEWALL_1117 600 0.91 1.98 3.9 511.39 12THREEWALL_1117 600 0.91 1.98 4.2 406.63 12THREEWALL_1117 600 0.91 1.98 4.5 321.86 12THREEWALL_1117 600 0.91 1.98 4.8 259.92 12THREEWALL_1117 600 0.91 1.98 5.1 212.13 12THREEWALL_1117 600 0.91 1.98 5.4 179.44 12THREEWALL_1117 600 0.91 1.98 5.7 154.98 12THREEWALL_1117 600 0.91 1.98 6 139.12 12

E-134 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
OBSTRUCTED PLUME FIRE MODELING RESULTS 

E-135 

Vertical Source Sensitivity Results 

Table E-5 

Vertical Fire Source Sensitivity Results 

Test HRR (kW) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) 

ARCH_1201 200 1.96 2.4 268.98

ARCH_1201 200 1.96 2.7 144.1

ARCH_1201 200 1.96 3 113.12

ARCH_1201 200 1.96 3.3 96.37

ARCH_1201 200 1.96 3.6 78.483

ARCH_1201 200 1.96 3.9 71.331

ARCH_1201 200 1.96 4.2 65.5

ARCH_1201 200 1.96 4.5 53.038

ARCH_1201 200 1.96 4.8 46.024

ARCH_1201 200 1.96 5.1 42.5

ARCH_1201 200 1.96 5.4 37.767

ARCH_1201 200 1.96 5.7 33.437

ARCH_1201 200 1.96 6 31.546

ARCH_1204 600 1.96 2.4 373.37

ARCH_1204 600 1.96 2.7 208.88

ARCH_1204 600 1.96 3 159.73

ARCH_1204 600 1.96 3.3 127.46

ARCH_1204 600 1.96 3.6 111.86

ARCH_1204 600 1.96 3.9 93.95

ARCH_1204 600 1.96 4.2 81.8

ARCH_1204 600 1.96 4.5 70.262

ARCH_1204 600 1.96 4.8 61.122

ARCH_1204 600 1.96 5.1 55.523

ARCH_1204 600 1.96 5.4 49.187

ARCH_1204 600 1.96 5.7 45.015

ARCH_1204 600 1.96 6 41.931

ARCH_1207 1000 1.96 2.4 548.76

ARCH_1207 1000 1.96 2.7 333.12

ARCH_1207 1000 1.96 3 244.24

ARCH_1207 1000 1.96 3.3 193.98

ARCH_1207 1000 1.96 3.6 165.92
OBSTRUCTED PLUME FIRE MODELING RESULTS 

E-136 

Table E-5 

Vertical Fire Source Sensitivity Results 

Test HRR (kW) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) 

ARCH_1207 1000 1.96 3.9 134.32

ARCH_1207 1000 1.96 4.2 116.62

ARCH_1207 1000 1.96 4.5 102.34

ARCH_1207 1000 1.96 4.8 93.31

ARCH_1207 1000 1.96 5.1 84.96

ARCH_1207 1000 1.96 5.4 76.94

ARCH_1207 1000 1.96 5.7 71.158

ARCH_1207 1000 1.96 6 67.532

OBST_1200 200 1.96 2.4 278.25

OBST_1200 200 1.96 2.7 191.68

OBST_1200 200 1.96 3 137.65

OBST_1200 200 1.96 3.3 116.8

OBST_1200 200 1.96 3.6 106.52

OBST_1200 200 1.96 3.9 103.48

OBST_1200 200 1.96 4.2 96.76

OBST_1200 200 1.96 4.5 93.14

OBST_1200 200 1.96 4.8 85.47

OBST_1200 200 1.96 5.1 82.24

OBST_1200 200 1.96 5.4 77.125

OBST_1200 200 1.96 5.7 68.407

OBST_1200 200 1.96 6 67.908

OBST_1203 600 1.96 2.4 395.28

OBST_1203 600 1.96 2.7 269.3

OBST_1203 600 1.96 3 200.42

OBST_1203 600 1.96 3.3 168.84

OBST_1203 600 1.96 3.6 162.48

OBST_1203 600 1.96 3.9 152.5

OBST_1203 600 1.96 4.2 142.48

OBST_1203 600 1.96 4.5 132.94

OBST_1203 600 1.96 4.8 124.94

OBST_1203 600 1.96 5.1 118.76

OBST_1203 600 1.96 5.4 112.77
OBSTRUCTED PLUME FIRE MODELING RESULTS 

E-137 

Table E-5 

Vertical Fire Source Sensitivity Results 

Test HRR (kW) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) 

OBST_1203 600 1.96 5.7 105.93

OBST_1203 600 1.96 6 99.98

OBST_1206 1000 1.96 2.4 571.45

OBST_1206 1000 1.96 2.7 426.7

OBST_1206 1000 1.96 3 324.5

OBST_1206 1000 1.96 3.3 250.95

OBST_1206 1000 1.96 3.6 218.76

OBST_1206 1000 1.96 3.9 203.03

OBST_1206 1000 1.96 4.2 194.93

OBST_1206 1000 1.96 4.5 184.31

OBST_1206 1000 1.96 4.8 176.19

OBST_1206 1000 1.96 5.1 167.67

OBST_1206 1000 1.96 5.4 157.48

OBST_1206 1000 1.96 5.7 147.61

OBST_1206 1000 1.96 6 138.06

THREEWALL_1202 200 1.96 2.4 389.57

THREEWALL_1202 200 1.96 2.7 196.97

THREEWALL_1202 200 1.96 3 166.17

THREEWALL_1202 200 1.96 3.3 127.37

THREEWALL_1202 200 1.96 3.6 108.9

THREEWALL_1202 200 1.96 3.9 100.05

THREEWALL_1202 200 1.96 4.2 87.32

THREEWALL_1202 200 1.96 4.5 75.058

THREEWALL_1202 200 1.96 4.8 66.517

THREEWALL_1202 200 1.96 5.1 61.544

THREEWALL_1202 200 1.96 5.4 61.094

THREEWALL_1202 200 1.96 5.7 53.701

THREEWALL_1202 200 1.96 6 49.642

THREEWALL_1205 600 1.96 2.4 656.67

THREEWALL_1205 600 1.96 2.7 324.79

THREEWALL_1205 600 1.96 3 246.83

THREEWALL_1205 600 1.96 3.3 193.16
OBSTRUCTED PLUME FIRE MODELING RESULTS 

E-138 

Table E-5 

Vertical Fire Source Sensitivity Results 

Test HRR (kW) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) 

THREEWALL_1205 600 1.96 3.6 166.46

THREEWALL_1205 600 1.96 3.9 144.38

THREEWALL_1205 600 1.96 4.2 127.18

THREEWALL_1205 600 1.96 4.5 114.05

THREEWALL_1205 600 1.96 4.8 104.54

THREEWALL_1205 600 1.96 5.1 95.21

THREEWALL_1205 600 1.96 5.4 84.74

THREEWALL_1205 600 1.96 5.7 78.468

THREEWALL_1205 600 1.96 6 74.278

THREEWALL_1208 1000 1.96 2.4 851.7

THREEWALL_1208 1000 1.96 2.7 522.48

THREEWALL_1208 1000 1.96 3 381.06

THREEWALL_1208 1000 1.96 3.3 293.78

THREEWALL_1208 1000 1.96 3.6 241

THREEWALL_1208 1000 1.96 3.9 203.84

THREEWALL_1208 1000 1.96 4.2 176.73

THREEWALL_1208 1000 1.96 4.5 151.32

THREEWALL_1208 1000 1.96 4.8 136.85

THREEWALL_1208 1000 1.96 5.1 123.86

THREEWALL_1208 1000 1.96 5.4 113.06

THREEWALL_1208 1000 1.96 5.7 106.48

THREEWALL_1208 1000 1.96 6 102.17
OBSTRUCTED PLUME FIRE MODELING RESULTS 

E-139 

Wall Surface Source Sensitivity Results 

Table E-6

Wall Surface Fire Source Sensitivity Results 

Test HRR (kW) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) 

ARCH_1300 200 N/A 2.4 217.1

ARCH_1300 200 N/A 2.7 138.23

ARCH_1300 200 N/A 3 112.58

ARCH_1300 200 N/A 3.3 86.48

ARCH_1300 200 N/A 3.6 70.548

ARCH_1300 200 N/A 3.9 59.215

ARCH_1300 200 N/A 4.2 50.1

ARCH_1300 200 N/A 4.5 40.591

ARCH_1300 200 N/A 4.8 38.02

ARCH_1300 200 N/A 5.1 32.326

ARCH_1300 200 N/A 5.4 30.396

ARCH_1300 200 N/A 5.7 26.979

ARCH_1300 200 N/A 6 25.194

ARCH_1301 600 N/A 2.4 393.79

ARCH_1301 600 N/A 2.7 209.47

ARCH_1301 600 N/A 3 151.92

ARCH_1301 600 N/A 3.3 116.88

ARCH_1301 600 N/A 3.6 103.04

ARCH_1301 600 N/A 3.9 94.12

ARCH_1301 600 N/A 4.2 86.7

ARCH_1301 600 N/A 4.5 77.009

ARCH_1301 600 N/A 4.8 69.681

ARCH_1301 600 N/A 5.1 63.48

ARCH_1301 600 N/A 5.4 57.863

ARCH_1301 600 N/A 5.7 53.021

ARCH_1301 600 N/A 6 48.236

ARCH_1302 1000 N/A 2.4 536.82

ARCH_1302 1000 N/A 2.7 273.11

ARCH_1302 1000 N/A 3 195.72

ARCH_1302 1000 N/A 3.3 151.17

ARCH_1302 1000 N/A 3.6 130.34

ARCH_1302 1000 N/A 3.9 119.55

ARCH_1302 1000 N/A 4.2 109.61

ARCH_1302 1000 N/A 4.5 99.71

ARCH_1302 1000 N/A 4.8 92.99
OBSTRUCTED PLUME FIRE MODELING RESULTS 

E-140 

Table E-6

Wall Surface Fire Source Sensitivity Results 

Test HRR (kW) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) 

ARCH_1302 1000 N/A 5.1 86.59

ARCH_1302 1000 N/A 5.4 79.901

ARCH_1302 1000 N/A 5.7 74.873

ARCH_1302 1000 N/A 6 69.845

THREEWALL_1303 200 N/A 2.4 194.03

THREEWALL_1303 200 N/A 2.7 111.49

THREEWALL_1303 200 N/A 3 86.47

THREEWALL_1303 200 N/A 3.3 72.89

THREEWALL_1303 200 N/A 3.6 58.965

THREEWALL_1303 200 N/A 3.9 53.597

THREEWALL_1303 200 N/A 4.2 48.005

THREEWALL_1303 200 N/A 4.5 41.282

THREEWALL_1303 200 N/A 4.8 37.605

THREEWALL_1303 200 N/A 5.1 34.67

THREEWALL_1303 200 N/A 5.4 34.316

THREEWALL_1303 200 N/A 5.7 29.146

THREEWALL_1303 200 N/A 6 28.554

THREEWALL_1304 600 N/A 2.4 351.26

THREEWALL_1304 600 N/A 2.7 202.93

THREEWALL_1304 600 N/A 3 160.17

THREEWALL_1304 600 N/A 3.3 124.65

THREEWALL_1304 600 N/A 3.6 108.96

THREEWALL_1304 600 N/A 3.9 94.17

THREEWALL_1304 600 N/A 4.2 86.77

THREEWALL_1304 600 N/A 4.5 79.251

THREEWALL_1304 600 N/A 4.8 70.232

THREEWALL_1304 600 N/A 5.1 63.272

THREEWALL_1304 600 N/A 5.4 56.567

THREEWALL_1304 600 N/A 5.7 50.222

THREEWALL_1304 600 N/A 6 48.415

THREEWALL_1306 1000 N/A 2.4 462.11

THREEWALL_1306 1000 N/A 2.7 283.33

THREEWALL_1306 1000 N/A 3 229.63

THREEWALL_1306 1000 N/A 3.3 185.73

THREEWALL_1306 1000 N/A 3.6 159.07

THREEWALL_1306 1000 N/A 3.9 133.87
OBSTRUCTED PLUME FIRE MODELING RESULTS 

E-141 

Table E-6

Wall Surface Fire Source Sensitivity Results 

Test HRR (kW) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) 

THREEWALL_1306 1000 N/A 4.2 119.87

THREEWALL_1306 1000 N/A 4.5 103.54

THREEWALL_1306 1000 N/A 4.8 94.86

THREEWALL_1306 1000 N/A 5.1 86.99

THREEWALL_1306 1000 N/A 5.4 80.12

THREEWALL_1306 1000 N/A 5.7 73.768

THREEWALL_1306 1000 N/A 6 68.647
OBSTRUCTED PLUME FIRE MODELING RESULTS 

E-142 

Soffit Sensitivity Results 

Table E-7

Soffit Sensitivity Results 

Test HRR (kW) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) 

ARCH_1401 200 1.14 2.4 171.43

ARCH_1401 200 1.14 2.7 107.11

ARCH_1401 200 1.14 3 92.4

ARCH_1401 200 1.14 3.3 74.129

ARCH_1401 200 1.14 3.6 68.538

ARCH_1401 200 1.14 3.9 53.736

ARCH_1401 200 1.14 4.2 49.268

ARCH_1401 200 1.14 4.5 43.278

ARCH_1401 200 1.14 4.8 38.74

ARCH_1401 200 1.14 5.1 35.033

ARCH_1401 200 1.14 5.4 30.479

ARCH_1401 200 1.14 5.7 29.695

ARCH_1401 200 1.14 6 26.62

ARCH_1404 600 1.14 2.4 271.05

ARCH_1404 600 1.14 2.7 177.17

ARCH_1404 600 1.14 3 143.77

ARCH_1404 600 1.14 3.3 115.75

ARCH_1404 600 1.14 3.6 102.35

ARCH_1404 600 1.14 3.9 90.26

ARCH_1404 600 1.14 4.2 79.924

ARCH_1404 600 1.14 4.5 71.303

ARCH_1404 600 1.14 4.8 66.625

ARCH_1404 600 1.14 5.1 60.925

ARCH_1404 600 1.14 5.4 53.258

ARCH_1404 600 1.14 5.7 46.84

ARCH_1404 600 1.14 6 44.228

ARCH_1407 1000 1.14 2.4 411.81

ARCH_1407 1000 1.14 2.7 257.94

ARCH_1407 1000 1.14 3 204.41

ARCH_1407 1000 1.14 3.3 171.02

ARCH_1407 1000 1.14 3.6 146.92

ARCH_1407 1000 1.14 3.9 124.11

ARCH_1407 1000 1.14 4.2 110.35

ARCH_1407 1000 1.14 4.5 95.13

ARCH_1407 1000 1.14 4.8 85.1
OBSTRUCTED PLUME FIRE MODELING RESULTS 

E-143 

Table E-7

Soffit Sensitivity Results 

Test HRR (kW) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) 

ARCH_1407 1000 1.14 5.1 78.778

ARCH_1407 1000 1.14 5.4 70.232

ARCH_1407 1000 1.14 5.7 65.497

ARCH_1410 200 1.98 2.4 738.18

ARCH_1410 200 1.98 2.7 531.25

ARCH_1410 200 1.98 3 321.95

ARCH_1410 200 1.98 3.3 231.67

ARCH_1410 200 1.98 3.6 200.36

ARCH_1410 200 1.98 3.9 165.42

ARCH_1410 200 1.98 4.2 132.76

ARCH_1410 200 1.98 4.5 96.17

ARCH_1410 200 1.98 4.8 86.44

ARCH_1410 200 1.98 5.1 85.38

ARCH_1410 200 1.98 5.4 70.331

ARCH_1410 200 1.98 5.7 57.028

ARCH_1410 200 1.98 6 53.461

ARCH_1413 600 1.98 2.4 954.42

ARCH_1413 600 1.98 2.7 789.76

ARCH_1413 600 1.98 3 604.22

ARCH_1413 600 1.98 3.3 423.99

ARCH_1413 600 1.98 3.6 326.94

ARCH_1413 600 1.98 3.9 257.85

ARCH_1413 600 1.98 4.2 212.79

ARCH_1413 600 1.98 4.5 172.49

ARCH_1413 600 1.98 4.8 146.63

ARCH_1413 600 1.98 5.1 127.04

ARCH_1413 600 1.98 5.4 111.77

ARCH_1413 600 1.98 5.7 99.91

ARCH_1413 600 1.98 6 91.55

ARCH_1416 1000 1.98 2.4 994.8

ARCH_1416 1000 1.98 2.7 962.81

ARCH_1416 1000 1.98 3 785.87

ARCH_1416 1000 1.98 3.3 592.31

ARCH_1416 1000 1.98 3.6 444.35

ARCH_1416 1000 1.98 3.9 331.3

ARCH_1416 1000 1.98 4.2 266.22
OBSTRUCTED PLUME FIRE MODELING RESULTS 

E-144 

Table E-7

Soffit Sensitivity Results 

Test HRR (kW) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) 

ARCH_1416 1000 1.98 4.5 223.96

ARCH_1416 1000 1.98 4.8 197.1

ARCH_1416 1000 1.98 5.1 175.42

ARCH_1416 1000 1.98 5.4 151.29

ARCH_1416 1000 1.98 5.7 130.44

ARCH_1416 1000 1.98 6 121.45

OBST_1400 200 1.14 2.4 184.04

OBST_1400 200 1.14 2.7 118.62

OBST_1400 200 1.14 3 91.06

OBST_1400 200 1.14 3.3 85.89

OBST_1400 200 1.14 3.6 79.421

OBST_1400 200 1.14 3.9 72.139

OBST_1400 200 1.14 4.2 71.684

OBST_1400 200 1.14 4.5 62.392

OBST_1400 200 1.14 4.8 58.739

OBST_1400 200 1.14 5.1 60.088

OBST_1400 200 1.14 5.4 50.108

OBST_1400 200 1.14 5.7 47.747

OBST_1400 200 1.14 6 41.442

OBST_1403 600 1.14 2.4 158.1

OBST_1403 600 1.14 2.7 95.82

OBST_1403 600 1.14 3 80.94

OBST_1403 600 1.14 3.3 75.894

OBST_1403 600 1.14 3.6 72.973

OBST_1403 600 1.14 3.9 68.895

OBST_1403 600 1.14 4.2 65.861

OBST_1403 600 1.14 4.5 60.361

OBST_1403 600 1.14 4.8 55.75

OBST_1403 600 1.14 5.1 52.542

OBST_1403 600 1.14 5.4 49.347

OBST_1403 600 1.14 5.7 46.011

OBST_1403 600 1.14 6 43.146

OBST_1406 1000 1.14 2.4 556.48

OBST_1406 1000 1.14 2.7 305.76

OBST_1406 1000 1.14 3 234.27

OBST_1406 1000 1.14 3.3 209.24
OBSTRUCTED PLUME FIRE MODELING RESULTS 

E-145 

Table E-7

Soffit Sensitivity Results 

Test HRR (kW) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) 

OBST_1406 1000 1.14 3.6 194.4

OBST_1406 1000 1.14 3.9 182.5

OBST_1406 1000 1.14 4.2 173.52

OBST_1406 1000 1.14 4.5 164.84

OBST_1406 1000 1.14 4.8 156.91

OBST_1406 1000 1.14 5.1 148.39

OBST_1406 1000 1.14 5.4 138.98

OBST_1406 1000 1.14 5.7 128.8

OBST_1409 200 1.98 2.4 402.02

OBST_1409 200 1.98 2.7 256.32

OBST_1409 200 1.98 3 190.56

OBST_1409 200 1.98 3.3 147.92

OBST_1409 200 1.98 3.6 132.96

OBST_1409 200 1.98 3.9 126.64

OBST_1409 200 1.98 4.2 114.66

OBST_1409 200 1.98 4.5 109.51

OBST_1409 200 1.98 4.8 96.45

OBST_1409 200 1.98 5.1 86.48

OBST_1409 200 1.98 5.4 80.21

OBST_1409 200 1.98 5.7 76.865

OBST_1409 200 1.98 6 58.705

OBST_1412 600 1.98 2.4 370.99

OBST_1412 600 1.98 2.7 223.24

OBST_1412 600 1.98 3 176.23

OBST_1412 600 1.98 3.3 147.97

OBST_1412 600 1.98 3.6 143.57

OBST_1412 600 1.98 3.9 135.99

OBST_1412 600 1.98 4.2 125.67

OBST_1412 600 1.98 4.5 113.93

OBST_1412 600 1.98 4.8 104.76

OBST_1412 600 1.98 5.1 97.8

OBST_1412 600 1.98 5.4 88.74

OBST_1412 600 1.98 5.7 77.893

OBST_1412 600 1.98 6 69.543

OBST_1415 1000 1.98 2.4 905.23

OBST_1415 1000 1.98 2.7 642.45
OBSTRUCTED PLUME FIRE MODELING RESULTS 

E-146 

Table E-7

Soffit Sensitivity Results 

Test HRR (kW) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) 

OBST_1415 1000 1.98 3 470.26

OBST_1415 1000 1.98 3.3 424.23

OBST_1415 1000 1.98 3.6 397.15

OBST_1415 1000 1.98 3.9 357.09

OBST_1415 1000 1.98 4.2 327.61

OBST_1415 1000 1.98 4.5 301.04

OBST_1415 1000 1.98 4.8 275.26

OBST_1415 1000 1.98 5.1 249.89

OBST_1415 1000 1.98 5.4 222.05

OBST_1415 1000 1.98 5.7 192.79

OBST_1415 1000 1.98 6 169.22

THREEWALL_1402 200 1.14 2.4 193.98

THREEWALL_1402 200 1.14 2.7 145.26

THREEWALL_1402 200 1.14 3 125.38

THREEWALL_1402 200 1.14 3.3 101.96

THREEWALL_1402 200 1.14 3.6 84.66

THREEWALL_1402 200 1.14 3.9 72.809

THREEWALL_1402 200 1.14 4.2 60.607

THREEWALL_1402 200 1.14 4.5 54.012

THREEWALL_1402 200 1.14 4.8 51.346

THREEWALL_1402 200 1.14 5.1 41.729

THREEWALL_1402 200 1.14 5.4 36.629

THREEWALL_1402 200 1.14 5.7 35.579

THREEWALL_1402 200 1.14 6 32.219

THREEWALL_1405 600 1.14 2.4 476.72

THREEWALL_1405 600 1.14 2.7 316.14

THREEWALL_1405 600 1.14 3 233.69

THREEWALL_1405 600 1.14 3.3 189.15

THREEWALL_1405 600 1.14 3.6 163.93

THREEWALL_1405 600 1.14 3.9 138.63

THREEWALL_1405 600 1.14 4.2 121.14

THREEWALL_1405 600 1.14 4.5 105.84

THREEWALL_1405 600 1.14 4.8 94.26

THREEWALL_1405 600 1.14 5.1 87.32

THREEWALL_1405 600 1.14 5.4 80.06

THREEWALL_1405 600 1.14 5.7 72.691
OBSTRUCTED PLUME FIRE MODELING RESULTS 

E-147 

Table E-7

Soffit Sensitivity Results 

Test HRR (kW) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) 

THREEWALL_1405 600 1.14 6 67.461

THREEWALL_1408 1000 1.14 2.4 625.88

THREEWALL_1408 1000 1.14 3 379.77

THREEWALL_1408 1000 1.14 3.3 307.8

THREEWALL_1408 1000 1.14 3.6 254.14

THREEWALL_1408 1000 1.14 3.9 206.26

THREEWALL_1408 1000 1.14 4.2 177.04

THREEWALL_1408 1000 1.14 4.5 147.71

THREEWALL_1408 1000 1.14 4.8 132.24

THREEWALL_1408 1000 1.14 5.1 115.84

THREEWALL_1408 1000 1.14 5.4 102.15

THREEWALL_1408 1000 1.14 5.7 95.34

THREEWALL_1408 1000 1.14 6 91.38

THREEWALL_1411 200 1.98 2.4 878.98

THREEWALL_1411 200 1.98 2.7 769.44

THREEWALL_1411 200 1.98 3 459.87

THREEWALL_1411 200 1.98 3.3 320.98

THREEWALL_1411 200 1.98 3.6 277.11

THREEWALL_1411 200 1.98 3.9 225.03

THREEWALL_1411 200 1.98 4.2 158.3

THREEWALL_1411 200 1.98 4.5 136.72

THREEWALL_1411 200 1.98 4.8 105.45

THREEWALL_1411 200 1.98 5.1 91.15

THREEWALL_1411 200 1.98 5.4 89.57

THREEWALL_1411 200 1.98 5.7 67.042

THREEWALL_1411 200 1.98 6 65.321

THREEWALL_1414 600 1.98 2.4 1004.1

THREEWALL_1414 600 1.98 2.7 1018.4

THREEWALL_1414 600 1.98 3 889.06

THREEWALL_1414 600 1.98 3.3 677.2

THREEWALL_1414 600 1.98 3.6 549.32

THREEWALL_1414 600 1.98 3.9 393.67

THREEWALL_1414 600 1.98 4.2 311.25

THREEWALL_1414 600 1.98 4.5 250.77

THREEWALL_1414 600 1.98 4.8 208.71

THREEWALL_1414 600 1.98 5.1 176.82
OBSTRUCTED PLUME FIRE MODELING RESULTS 

E-148 

Table E-7

Soffit Sensitivity Results 

Test HRR (kW) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) 

THREEWALL_1414 600 1.98 5.4 151.71

THREEWALL_1414 600 1.98 5.7 129

THREEWALL_1414 600 1.98 6 117.24

THREEWALL_1417 1000 1.98 2.4 985.6

THREEWALL_1417 1000 1.98 3 1016.6

THREEWALL_1417 1000 1.98 3.3 878.92

THREEWALL_1417 1000 1.98 3.6 749.52

THREEWALL_1417 1000 1.98 3.9 564.62

THREEWALL_1417 1000 1.98 4.2 441.37

THREEWALL_1417 1000 1.98 4.5 331.07

THREEWALL_1417 1000 1.98 4.8 264.23

THREEWALL_1417 1000 1.98 5.1 231.36

THREEWALL_1417 1000 1.98 5.4 198.27

THREEWALL_1417 1000 1.98 5.7 175.81

THREEWALL_1417 1000 1.98 6 160.01
OBSTRUCTED PLUME FIRE MODELING RESULTS 

E-149 

Thickness of Steel Enclosure Sensitivity Results 

Table E-8

Thickness of Steel Enclosure Sensitivity Results 

Test HRR 

(kW) 

Source Height 

(m) 

Elevation 

(m) 

Maximum Plume Temperature 

Rise (C) 

Thickness

(m) 

ARCH_1501 200 1.14 2.4 250.82 0.001

ARCH_1501 200 1.14 2.7 122.91 0.001

ARCH_1501 200 1.14 3 91.45 0.001

ARCH_1501 200 1.14 3.3 73.979 0.001

ARCH_1501 200 1.14 3.6 65.335 0.001

ARCH_1501 200 1.14 3.9 57.142 0.001

ARCH_1501 200 1.14 4.2 51.134 0.001

ARCH_1501 200 1.14 4.5 44.485 0.001

ARCH_1501 200 1.14 4.8 40.524 0.001

ARCH_1501 200 1.14 5.1 35.815 0.001

ARCH_1501 200 1.14 5.4 30.292 0.001

ARCH_1501 200 1.14 5.7 26.372 0.001

ARCH_1501 200 1.14 6 23.782 0.001

ARCH_1504 600 1.14 2.4 435.35 0.001

ARCH_1504 600 1.14 2.7 224.49 0.001

ARCH_1504 600 1.14 3 170.42 0.001

ARCH_1504 600 1.14 3.3 138.38 0.001

ARCH_1504 600 1.14 3.6 118.28 0.001

ARCH_1504 600 1.14 3.9 101.34 0.001

ARCH_1504 600 1.14 4.2 88.47 0.001

ARCH_1504 600 1.14 4.5 77.319 0.001

ARCH_1504 600 1.14 4.8 70.064 0.001

ARCH_1504 600 1.14 5.1 63.279 0.001

ARCH_1504 600 1.14 5.4 55.88 0.001

ARCH_1504 600 1.14 5.7 49.069 0.001

ARCH_1504 600 1.14 6 46.318 0.001

ARCH_1507 1000 1.14 2.4 492.48 0.001

ARCH_1507 1000 1.14 2.7 277.71 0.001

ARCH_1507 1000 1.14 3 204.56 0.001

ARCH_1507 1000 1.14 3.3 167.04 0.001

ARCH_1507 1000 1.14 3.6 141.3 0.001

ARCH_1507 1000 1.14 3.9 122.79 0.001

ARCH_1507 1000 1.14 4.2 108.05 0.001

ARCH_1507 1000 1.14 4.5 96.97 0.001

ARCH_1507 1000 1.14 4.8 87.07 0.001
OBSTRUCTED PLUME FIRE MODELING RESULTS 

E-150 

Table E-8

Thickness of Steel Enclosure Sensitivity Results 

Test HRR 

(kW) 

Source Height 

(m) 

Elevation 

(m) 

Maximum Plume Temperature 

Rise (C) 

Thickness

(m) 

ARCH_1507 1000 1.14 5.1 80.05 0.001

ARCH_1507 1000 1.14 5.4 72.417 0.001

ARCH_1507 1000 1.14 5.7 66.252 0.001

OBST_1500 200 1.14 2.4 221.43 0.001

OBST_1500 200 1.14 2.7 142.99 0.001

OBST_1500 200 1.14 3 111.06 0.001

OBST_1500 200 1.14 3.3 96.39 0.001

OBST_1500 200 1.14 3.6 91.29 0.001

OBST_1500 200 1.14 3.9 86.53 0.001

OBST_1500 200 1.14 4.2 82.34 0.001

OBST_1500 200 1.14 4.5 76.998 0.001

OBST_1500 200 1.14 4.8 72.526 0.001

OBST_1500 200 1.14 5.1 68.481 0.001

OBST_1500 200 1.14 5.4 63.629 0.001

OBST_1500 200 1.14 5.7 59.183 0.001

OBST_1500 200 1.14 6 55.542 0.001

OBST_1503 600 1.14 2.4 527.39 0.001

OBST_1503 600 1.14 2.7 357.75 0.001

OBST_1503 600 1.14 3 259.18 0.001

OBST_1503 600 1.14 3.3 207.71 0.001

OBST_1503 600 1.14 3.6 192.77 0.001

OBST_1503 600 1.14 3.9 185.88 0.001

OBST_1503 600 1.14 4.2 178.84 0.001

OBST_1503 600 1.14 4.5 167.41 0.001

OBST_1503 600 1.14 4.8 156.9 0.001

OBST_1503 600 1.14 5.1 147.64 0.001

OBST_1503 600 1.14 5.4 136.39 0.001

OBST_1503 600 1.14 5.7 127.67 0.001

OBST_1503 600 1.14 6 119.2 0.001

OBST_1506 1000 1.14 2.4 644.94 0.001

OBST_1506 1000 1.14 2.7 476.7 0.001

OBST_1506 1000 1.14 3 361.87 0.001

OBST_1506 1000 1.14 3.3 282.67 0.001

OBST_1506 1000 1.14 3.6 247.17 0.001

OBST_1506 1000 1.14 3.9 232.76 0.001

OBST_1506 1000 1.14 4.2 222.02 0.001
OBSTRUCTED PLUME FIRE MODELING RESULTS 

E-151 

Table E-8

Thickness of Steel Enclosure Sensitivity Results 

Test HRR 

(kW) 

Source Height 

(m) 

Elevation 

(m) 

Maximum Plume Temperature 

Rise (C) 

Thickness

(m) 

OBST_1506 1000 1.14 4.5 209.18 0.001

OBST_1506 1000 1.14 4.8 200.17 0.001

OBST_1506 1000 1.14 5.1 189.85 0.001

OBST_1506 1000 1.14 5.4 178.66 0.001

OBST_1506 1000 1.14 5.7 168.58 0.001

THREEWALL_1502 200 1.14 2.4 303.37 0.001

THREEWALL_1502 200 1.14 2.7 165.48 0.001

THREEWALL_1502 200 1.14 3 121.14 0.001

THREEWALL_1502 200 1.14 3.3 98 0.001

THREEWALL_1502 200 1.14 3.6 88.09 0.001

THREEWALL_1502 200 1.14 3.9 79.77 0.001

THREEWALL_1502 200 1.14 4.2 72.972 0.001

THREEWALL_1502 200 1.14 4.5 64.726 0.001

THREEWALL_1502 200 1.14 4.8 59.19 0.001

THREEWALL_1502 200 1.14 5.1 54.454 0.001

THREEWALL_1502 200 1.14 5.4 47.665 0.001

THREEWALL_1502 200 1.14 5.7 42.54 0.001

THREEWALL_1502 200 1.14 6 39.323 0.001

THREEWALL_1505 600 1.14 2.4 623.89 0.001

THREEWALL_1505 600 1.14 2.7 350.4 0.001

THREEWALL_1505 600 1.14 3 267.62 0.001

THREEWALL_1505 600 1.14 3.3 212.45 0.001

THREEWALL_1505 600 1.14 3.6 185.57 0.001

THREEWALL_1505 600 1.14 3.9 155.18 0.001

THREEWALL_1505 600 1.14 4.2 131.07 0.001

THREEWALL_1505 600 1.14 4.5 113.77 0.001

THREEWALL_1505 600 1.14 4.8 100.05 0.001

THREEWALL_1505 600 1.14 5.1 86.74 0.001

THREEWALL_1505 600 1.14 5.4 75.044 0.001

THREEWALL_1505 600 1.14 5.7 67.165 0.001

THREEWALL_1505 600 1.14 6 63.244 0.001

THREEWALL_1508 1000 1.14 2.4 715.92 0.001

THREEWALL_1508 1000 1.14 2.7 476.43 0.001

THREEWALL_1508 1000 1.14 3 360.41 0.001

THREEWALL_1508 1000 1.14 3.3 278.18 0.001

THREEWALL_1508 1000 1.14 3.6 231.1 0.001
OBSTRUCTED PLUME FIRE MODELING RESULTS 

E-152 

Table E-8

Thickness of Steel Enclosure Sensitivity Results 

Test HRR 

(kW) 

Source Height 

(m) 

Elevation 

(m) 

Maximum Plume Temperature 

Rise (C) 

Thickness

(m) 

THREEWALL_1508 1000 1.14 3.9 195.64 0.001

THREEWALL_1508 1000 1.14 4.2 166.35 0.001

THREEWALL_1508 1000 1.14 4.5 147.25 0.001

THREEWALL_1508 1000 1.14 4.8 134.56 0.001

THREEWALL_1508 1000 1.14 5.1 123.22 0.001

THREEWALL_1508 1000 1.14 5.4 110.95 0.001

THREEWALL_1508 1000 1.14 5.7 104.12 0.001

THREEWALL_1511 200 1.14 2.4 304.79 0.01

THREEWALL_1511 200 1.14 2.7 160.73 0.01

THREEWALL_1511 200 1.14 3 119.09 0.01

THREEWALL_1511 200 1.14 3.3 97.25 0.01

THREEWALL_1511 200 1.14 3.6 85.38 0.01

THREEWALL_1511 200 1.14 3.9 74.484 0.01

THREEWALL_1511 200 1.14 4.2 66.641 0.01

THREEWALL_1511 200 1.14 4.5 60.376 0.01

THREEWALL_1511 200 1.14 4.8 52.668 0.01

THREEWALL_1511 200 1.14 5.1 47.908 0.01

THREEWALL_1511 200 1.14 5.4 43.55 0.01

THREEWALL_1511 200 1.14 5.7 39.752 0.01

THREEWALL_1511 200 1.14 6 35.703 0.01

THREEWALL_1514 600 1.14 2.4 595.67 0.01

THREEWALL_1514 600 1.14 2.7 324.91 0.01

THREEWALL_1514 600 1.14 3 240.21 0.01

THREEWALL_1514 600 1.14 3.3 187.97 0.01

THREEWALL_1514 600 1.14 3.6 163.55 0.01

THREEWALL_1514 600 1.14 3.9 139.83 0.01

THREEWALL_1514 600 1.14 4.2 120.71 0.01

THREEWALL_1514 600 1.14 4.5 104.05 0.01

THREEWALL_1514 600 1.14 4.8 92.7 0.01

THREEWALL_1514 600 1.14 5.1 85.08 0.01

THREEWALL_1514 600 1.14 5.4 76.946 0.01

THREEWALL_1514 600 1.14 5.7 70.893 0.01

THREEWALL_1514 600 1.14 6 67.715 0.01

THREEWALL_1517 1000 1.14 2.4 701.19 0.01

THREEWALL_1517 1000 1.14 2.7 470.49 0.01

THREEWALL_1517 1000 1.14 3 346.27 0.01
OBSTRUCTED PLUME FIRE MODELING RESULTS 

E-153 

Table E-8

Thickness of Steel Enclosure Sensitivity Results 

Test HRR 

(kW) 

Source Height 

(m) 

Elevation 

(m) 

Maximum Plume Temperature 

Rise (C) 

Thickness

(m) 

THREEWALL_1517 1000 1.14 3.3 262.03 0.01

THREEWALL_1517 1000 1.14 3.6 220.57 0.01

THREEWALL_1517 1000 1.14 3.9 185.24 0.01

THREEWALL_1517 1000 1.14 4.2 163.31 0.01

THREEWALL_1517 1000 1.14 4.5 140.66 0.01

THREEWALL_1517 1000 1.14 4.8 125.6 0.01

THREEWALL_1517 1000 1.14 5.1 116.23 0.01

THREEWALL_1517 1000 1.14 5.4 104.95 0.01

THREEWALL_1517 1000 1.14 5.7 93.75 0.01

ARCH_1510 200 1.14 2.4 228.86 0.01

ARCH_1510 200 1.14 2.7 116.86 0.01

ARCH_1510 200 1.14 3 86.34 0.01

ARCH_1510 200 1.14 3.3 69.641 0.01

ARCH_1510 200 1.14 3.6 61.122 0.01

ARCH_1510 200 1.14 3.9 52.889 0.01

ARCH_1510 200 1.14 4.2 46.881 0.01

ARCH_1510 200 1.14 4.5 41.449 0.01

ARCH_1510 200 1.14 4.8 37.267 0.01

ARCH_1510 200 1.14 5.1 33.707 0.01

ARCH_1510 200 1.14 5.4 30.218 0.01

ARCH_1510 200 1.14 5.7 26.702 0.01

ARCH_1510 200 1.14 6 24.662 0.01

ARCH_1513 600 1.14 2.4 377.92 0.01

ARCH_1513 600 1.14 2.7 209.24 0.01

ARCH_1513 600 1.14 3 155.21 0.01

ARCH_1513 600 1.14 3.3 124.19 0.01

ARCH_1513 600 1.14 3.6 107.66 0.01

ARCH_1513 600 1.14 3.9 95.51 0.01

ARCH_1513 600 1.14 4.2 85.55 0.01

ARCH_1513 600 1.14 4.5 74.663 0.01

ARCH_1513 600 1.14 4.8 67.36 0.01

ARCH_1513 600 1.14 5.1 60.475 0.01

ARCH_1513 600 1.14 5.4 53.375 0.01

ARCH_1513 600 1.14 5.7 48.259 0.01

ARCH_1513 600 1.14 6 43.989 0.01

ARCH_1516 1000 1.14 2.4 474.54 0.01
OBSTRUCTED PLUME FIRE MODELING RESULTS 

E-154 

Table E-8

Thickness of Steel Enclosure Sensitivity Results 

Test HRR 

(kW) 

Source Height 

(m) 

Elevation 

(m) 

Maximum Plume Temperature 

Rise (C) 

Thickness

(m) 

ARCH_1516 1000 1.14 2.7 274.81 0.01

ARCH_1516 1000 1.14 3 198.87 0.01

ARCH_1516 1000 1.14 3.3 153.78 0.01

ARCH_1516 1000 1.14 3.6 132.35 0.01

ARCH_1516 1000 1.14 3.9 112.46 0.01

ARCH_1516 1000 1.14 4.2 100.01 0.01

ARCH_1516 1000 1.14 4.5 89.47 0.01

ARCH_1516 1000 1.14 4.8 78.582 0.01

ARCH_1516 1000 1.14 5.1 73.207 0.01

ARCH_1516 1000 1.14 5.4 65.564 0.01

ARCH_1516 1000 1.14 5.7 61.595 0.01

OBST_1509 200 1.14 2.4 220.64 0.01

OBST_1509 200 1.14 2.7 143.53 0.01

OBST_1509 200 1.14 3 108.73 0.01

OBST_1509 200 1.14 3.3 93.59 0.01

OBST_1509 200 1.14 3.6 87.24 0.01

OBST_1509 200 1.14 3.9 81.81 0.01

OBST_1509 200 1.14 4.2 77.448 0.01

OBST_1509 200 1.14 4.5 71.911 0.01

OBST_1509 200 1.14 4.8 66.742 0.01

OBST_1509 200 1.14 5.1 61.984 0.01

OBST_1509 200 1.14 5.4 56.47 0.01

OBST_1509 200 1.14 5.7 52.427 0.01

OBST_1509 200 1.14 6 48.606 0.01

OBST_1512 600 1.14 2.4 500.81 0.01

OBST_1512 600 1.14 2.7 344.7 0.01

OBST_1512 600 1.14 3 248.73 0.01

OBST_1512 600 1.14 3.3 212.99 0.01

OBST_1512 600 1.14 3.6 191.17 0.01

OBST_1512 600 1.14 3.9 177.62 0.01

OBST_1512 600 1.14 4.2 171.53 0.01

OBST_1512 600 1.14 4.5 162.67 0.01

OBST_1512 600 1.14 4.8 155.08 0.01

OBST_1512 600 1.14 5.1 147.56 0.01

OBST_1512 600 1.14 5.4 136.28 0.01

OBST_1512 600 1.14 5.7 124.2 0.01
OBSTRUCTED PLUME FIRE MODELING RESULTS 

E-155 

Table E-8

Thickness of Steel Enclosure Sensitivity Results 

Test HRR 

(kW) 

Source Height 

(m) 

Elevation 

(m) 

Maximum Plume Temperature 

Rise (C) 

Thickness

(m) 

OBST_1512 600 1.14 6 114.51 0.01

OBST_1515 1000 1.14 2.4 639.31 0.01

OBST_1515 1000 1.14 2.7 488.85 0.01

OBST_1515 1000 1.14 3 345.77 0.01

OBST_1515 1000 1.14 3.3 278.41 0.01

OBST_1515 1000 1.14 3.6 247.68 0.01

OBST_1515 1000 1.14 3.9 238.16 0.01

OBST_1515 1000 1.14 4.2 226.04 0.01

OBST_1515 1000 1.14 4.5 211.45 0.01

OBST_1515 1000 1.14 4.8 201.03 0.01

OBST_1515 1000 1.14 5.1 190.12 0.01

OBST_1515 1000 1.14 5.4 178.62 0.01
Horizontal Plume Shift and Angle Sensitivity Results 

Table E-9

Horizontal Plume Shift and Angle Sensitivity Results 

Test HRR (kW) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Diameter (m) 

RPO 

(m) 

RradThermoplastic 

(m) 

RradThermoset 

(m) Angle 

ARCH_1055 1000 1.14 2.4 686.62 0.91 0.7 2.40 1.88 13

ARCH_1055 1000 1.14 2.7 439.45 0.91 0.9 2.40 1.88 18ARCH_1055 1000 1.14 3 317.19 0.91 1.02 2.40 1.88 18ARCH_1055 1000 1.14 3.3 251.35 0.91 1.1 2.40 1.88 18ARCH_1055 1000 1.14 3.6 207.5 0.91 1.22 2.40 1.88 18ARCH_1055 1000 1.14 3.9 181.32 0.91 1.26 2.40 1.88 17ARCH_1055 1000 1.14 4.2 158.36 0.91 1.3 2.40 1.88 16ARCH_1055 1000 1.14 4.5 139.08 0.91 1.34 2.40 1.88 16ARCH_1055 1000 1.14 4.8 123.06 0.91 1.38 2.40 1.88 15ARCH_1056 1000 1.98 3.3 724.08 0.91 0.42 2.40 1.88 1ARCH_1056 1000 1.98 3.6 603.99 0.91 0.42 2.40 1.88 1ARCH_1064 1000 1.14 2.4 498.48 1.22 0.9 2.53 2.01 16ARCH_1064 1000 1.14 2.7 290.87 1.22 1.1 2.53 2.01 20ARCH_1064 1000 1.14 3 228.02 1.22 1.22 2.53 2.01 20ARCH_1064 1000 1.14 3.3 180.07 1.22 1.38 2.53 2.01 21ARCH_1064 1000 1.14 3.6 153.69 1.22 1.46 2.53 2.01 21ARCH_1064 1000 1.14 3.9 132.29 1.22 1.54 2.53 2.01 20ARCH_1064 1000 1.14 4.2 119.64 1.22 1.62 2.53 2.01 19ARCH_1065 1000 1.98 3 697.19 1.22 0.62 2.53 2.01 4ARCH_1065 1000 1.98 3.3 539.48 1.22 0.62 2.53 2.01 3ARCH_1065 1000 1.98 3.6 429.2 1.22 0.58 2.53 2.01 1ARCH_1065 1000 1.98 3.9 322.39 1.22 0.58 2.53 2.01 1

E-156 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-9

Horizontal Plume Shift and Angle Sensitivity Results 

Test HRR (kW) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Diameter (m) RPO (m) RradThermoplastic (m) RradThermoset (m) Angle 

ARCH_830 100 1.14 2.4 198.07 0.30 0.34 0.77 0.60 9

ARCH_830 100 1.14 2.7 112.16 0.30 0.5 0.77 0.60 13ARCH_836 50 1.98 2.4 246.03 0.30 0.3 0.58 0.46 22ARCH_836 50 1.98 2.7 126.04 0.30 0.38 0.58 0.46 19ARCH_837 100 1.98 2.4 511.44 0.30 0.22 0.77 0.60 11ARCH_837 100 1.98 2.7 255.75 0.30 0.38 0.77 0.60 19ARCH_837 100 1.98 3 171.73 0.30 0.42 0.77 0.60 16ARCH_837 100 1.98 3.3 118.23 0.30 0.46 0.77 0.60 14ARCH_894 200 1.14 2.4 239.92 0.61 0.54 1.16 0.93 12ARCH_894 200 1.14 2.7 120.83 0.61 0.82 1.16 0.93 19ARCH_895 300 1.14 2.4 330.38 0.61 0.5 1.36 1.08 10ARCH_895 300 1.14 2.7 172.02 0.61 0.78 1.36 1.08 18ARCH_895 300 1.14 3 125.64 0.61 0.9 1.36 1.08 19ARCH_896 400 1.14 2.4 555.97 0.61 0.5 1.53 1.20 10ARCH_896 400 1.14 2.7 253.67 0.61 0.7 1.53 1.20 15ARCH_896 400 1.14 3 172.71 0.61 0.86 1.53 1.20 18ARCH_896 400 1.14 3.3 135.45 0.61 0.94 1.53 1.20 17ARCH_896 400 1.14 3.6 115.42 0.61 1.1 1.53 1.20 19ARCH_897 500 1.14 2.4 685.87 0.61 0.46 1.68 1.31 9ARCH_897 500 1.14 2.7 385.73 0.61 0.62 1.68 1.31 13ARCH_897 500 1.14 3 255.53 0.61 0.7 1.68 1.31 13ARCH_897 500 1.14 3.3 187.46 0.61 0.82 1.68 1.31 14ARCH_897 500 1.14 3.6 155.04 0.61 0.98 1.68 1.31 16ARCH_897 500 1.14 3.9 131.32 0.61 1.02 1.68 1.31 15ARCH_897 500 1.14 4.2 114.1 0.61 1.06 1.68 1.31 14

E-157 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-9

Horizontal Plume Shift and Angle Sensitivity Results 

Test HRR (kW) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Diameter (m) RPO (m) RradThermoplastic (m) RradThermoset (m) Angle 

ARCH_898 600 1.14 2.4 757.31 0.61 0.5 1.82 1.41 10

ARCH_898 600 1.14 2.7 435.11 0.61 0.66 1.82 1.41 14ARCH_898 600 1.14 3 317.58 0.61 0.74 1.82 1.41 14ARCH_898 600 1.14 3.3 232 0.61 0.86 1.82 1.41 15ARCH_898 600 1.14 3.6 193.7 0.61 0.9 1.82 1.41 14ARCH_898 600 1.14 3.9 158.56 0.61 0.94 1.82 1.41 14ARCH_898 600 1.14 4.2 134.6 0.61 0.98 1.82 1.41 13ARCH_898 600 1.14 4.5 113.8 0.61 1.02 1.82 1.41 13ARCH_901 200 1.98 2.4 673.58 0.61 0.38 1.16 0.93 15ARCH_901 200 1.98 2.7 349.88 0.61 0.46 1.16 0.93 15ARCH_901 200 1.98 3 233.64 0.61 0.5 1.16 0.93 13ARCH_901 200 1.98 3.3 174.13 0.61 0.5 1.16 0.93 10ARCH_901 200 1.98 3.6 141.03 0.61 0.54 1.16 0.93 9ARCH_901 200 1.98 3.9 110.93 0.61 0.54 1.16 0.93 8ARCH_902 300 1.98 2.7 637.24 0.61 0.42 1.36 1.08 12ARCH_902 300 1.98 3 430.61 0.61 0.42 1.36 1.08 8ARCH_902 300 1.98 3.3 325.15 0.61 0.42 1.36 1.08 6ARCH_902 300 1.98 3.6 252.2 0.61 0.42 1.36 1.08 5ARCH_902 300 1.98 3.9 194.8 0.61 0.42 1.36 1.08 4ARCH_902 300 1.98 4.2 158.08 0.61 0.42 1.36 1.08 4ARCH_902 300 1.98 4.5 126.34 0.61 0.42 1.36 1.08 3ARCH_903 400 1.98 3 692.12 0.61 0.42 1.53 1.20 8ARCH_903 400 1.98 3.3 495.23 0.61 0.42 1.53 1.20 6ARCH_903 400 1.98 3.6 367.41 0.61 0.42 1.53 1.20 5ARCH_903 400 1.98 3.9 269.44 0.61 0.42 1.53 1.20 4

E-158 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-9

Horizontal Plume Shift and Angle Sensitivity Results 

Test HRR (kW) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Diameter (m) RPO (m) RradThermoplastic (m) RradThermoset (m) Angle 

ARCH_903 400 1.98 4.2 212.59 0.61 0.38 1.53 1.20 3

ARCH_903 400 1.98 4.5 163.52 0.61 0.38 1.53 1.20 3ARCH_903 400 1.98 4.8 137.37 0.61 0.38 1.53 1.20 2ARCH_903 400 1.98 5.1 118.3 0.61 0.38 1.53 1.20 2ARCH_904 500 1.98 3.3 733.53 0.61 0.38 1.68 1.31 5ARCH_904 500 1.98 3.6 574.4 0.61 0.42 1.68 1.31 5ARCH_904 500 1.98 3.9 414.66 0.61 0.42 1.68 1.31 4ARCH_904 500 1.98 4.2 314.39 0.61 0.38 1.68 1.31 3ARCH_904 500 1.98 4.5 236.69 0.61 0.38 1.68 1.31 3ARCH_904 500 1.98 4.8 193.59 0.61 0.34 1.68 1.31 1ARCH_904 500 1.98 5.1 162.15 0.61 0.34 1.68 1.31 1ARCH_904 500 1.98 5.4 138.1 0.61 0.3 1.68 1.31 1ARCH_904 500 1.98 5.7 115.49 0.61 0.3 1.68 1.31 0ARCH_905 600 1.98 3.6 714.06 0.61 0.42 1.82 1.41 5ARCH_905 600 1.98 3.9 513.68 0.61 0.42 1.82 1.41 4ARCH_905 600 1.98 4.2 398.77 0.61 0.42 1.82 1.41 4ARCH_905 600 1.98 4.5 299.55 0.61 0.42 1.82 1.41 3ARCH_905 600 1.98 4.8 243.95 0.61 0.38 1.82 1.41 2ARCH_905 600 1.98 5.1 198.04 0.61 0.38 1.82 1.41 2ARCH_905 600 1.98 5.4 162.57 0.61 0.34 1.82 1.41 1ARCH_905 600 1.98 5.7 134.08 0.61 0.34 1.82 1.41 1ARCH_905 600 1.98 6 116.82 0.61 0.34 1.82 1.41 1ARCH_958 300 1.14 2.4 201.52 0.91 0.78 1.50 1.21 17ARCH_958 300 1.14 2.7 115.52 0.91 1.1 1.50 1.21 24ARCH_959 400 1.14 2.4 254.49 0.91 0.74 1.67 1.34 15

E-159 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-9

Horizontal Plume Shift and Angle Sensitivity Results 

Test HRR (kW) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Diameter (m) RPO (m) RradThermoplastic (m) RradThermoset (m) Angle 

ARCH_959 400 1.14 2.7 150.19 0.91 1.06 1.67 1.34 23

ARCH_959 400 1.14 3 115.72 0.91 1.22 1.67 1.34 24ARCH_960 500 1.14 2.4 351.76 0.91 0.7 1.82 1.45 13ARCH_960 500 1.14 2.7 186.86 0.91 0.98 1.82 1.45 20ARCH_960 500 1.14 3 146.01 0.91 1.18 1.82 1.45 23ARCH_960 500 1.14 3.3 117.15 0.91 1.3 1.82 1.45 23ARCH_961 600 1.14 2.4 412.98 0.91 0.7 1.95 1.55 13ARCH_961 600 1.14 2.7 217.42 0.91 0.98 1.95 1.55 20ARCH_961 600 1.14 3 164.16 0.91 1.14 1.95 1.55 22ARCH_961 600 1.14 3.3 132.43 0.91 1.26 1.95 1.55 22ARCH_961 600 1.14 3.6 113.03 0.91 1.38 1.95 1.55 22ARCH_965 300 1.98 2.4 587.47 0.91 0.54 1.50 1.21 18ARCH_965 300 1.98 2.7 311.53 0.91 0.58 1.50 1.21 14ARCH_965 300 1.98 3 212.09 0.91 0.58 1.50 1.21 10ARCH_965 300 1.98 3.3 157.64 0.91 0.62 1.50 1.21 9ARCH_965 300 1.98 3.6 126.25 0.91 0.66 1.50 1.21 9ARCH_966 400 1.98 2.7 532.14 0.91 0.62 1.67 1.34 17ARCH_966 400 1.98 3 348 0.91 0.58 1.67 1.34 10ARCH_966 400 1.98 3.3 255.26 0.91 0.58 1.67 1.34 8ARCH_966 400 1.98 3.6 199.12 0.91 0.62 1.67 1.34 8ARCH_966 400 1.98 3.9 160.14 0.91 0.62 1.67 1.34 6ARCH_966 400 1.98 4.2 134.08 0.91 0.62 1.67 1.34 6ARCH_966 400 1.98 4.5 110.46 0.91 0.62 1.67 1.34 5ARCH_967 500 1.98 2.7 622.57 0.91 0.62 1.82 1.45 17ARCH_967 500 1.98 3 429.19 0.91 0.54 1.82 1.45 8

E-160 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-9

Horizontal Plume Shift and Angle Sensitivity Results 

Test HRR (kW) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Diameter (m) RPO (m) RradThermoplastic (m) RradThermoset (m) Angle 

ARCH_967 500 1.98 3.3 304.39 0.91 0.54 1.82 1.45 6

ARCH_967 500 1.98 3.6 232.72 0.91 0.58 1.82 1.45 6ARCH_967 500 1.98 3.9 196.54 0.91 0.58 1.82 1.45 5ARCH_967 500 1.98 4.2 163.63 0.91 0.58 1.82 1.45 5ARCH_967 500 1.98 4.5 133.81 0.91 0.58 1.82 1.45 4ARCH_967 500 1.98 4.5 133.81 0.91 0.58 1.82 1.45 4ARCH_967 500 1.98 4.8 114.52 0.91 0.58 1.82 1.45 4ARCH_968 600 1.98 2.7 697.36 0.91 0.5 1.95 1.55 8ARCH_968 600 1.98 3 529.99 0.91 0.54 1.95 1.55 8ARCH_968 600 1.98 3.3 392.15 0.91 0.54 1.95 1.55 6ARCH_968 600 1.98 3.6 291.81 0.91 0.54 1.95 1.55 5ARCH_968 600 1.98 3.9 225.14 0.91 0.5 1.95 1.55 3ARCH_968 600 1.98 4.2 189.01 0.91 0.5 1.95 1.55 2ARCH_968 600 1.98 4.5 153.48 0.91 0.46 1.95 1.55 1ARCH_968 600 1.98 4.8 129.83 0.91 0.42 1.95 1.55 0ARCH_968 600 1.98 5.1 111.62 0.91 0.42 1.95 1.55 0

THREEWALL_1058 1000 1.14 2.7 620.76 0.91 1.06 2.40 1.88 23THREEWALL_1058 1000 1.14 3 484.86 0.91 1.22 2.40 1.88 24THREEWALL_1058 1000 1.14 3.3 381.71 0.91 1.34 2.40 1.88 23THREEWALL_1058 1000 1.14 3.6 319.8 0.91 1.42 2.40 1.88 22THREEWALL_1058 1000 1.14 3.9 264.72 0.91 1.46 2.40 1.88 21THREEWALL_1058 1000 1.14 4.2 230.82 0.91 1.54 2.40 1.88 20THREEWALL_1058 1000 1.14 4.5 195.58 0.91 1.58 2.40 1.88 19THREEWALL_1058 1000 1.14 4.8 168.42 0.91 1.62 2.40 1.88 18THREEWALL_1058 1000 1.14 5.1 146.49 0.91 1.66 2.40 1.88 18

E-161 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-9

Horizontal Plume Shift and Angle Sensitivity Results 

Test HRR (kW) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Diameter (m) RPO (m) RradThermoplastic (m) RradThermoset (m) Angle 

THREEWALL_1058 1000 1.14 5.4 126.15 0.91 1.7 2.40 1.88 17

THREEWALL_1058 1000 1.14 5.7 115.05 0.91 1.58 2.40 1.88 14THREEWALL_1059 1000 1.98 3.9 646.54 0.91 0.58 2.40 1.88 5THREEWALL_1059 1000 1.98 4.2 527.72 0.91 0.58 2.40 1.88 5THREEWALL_1059 1000 1.98 4.5 411.6 0.91 0.58 2.40 1.88 4THREEWALL_1059 1000 1.98 4.8 334.89 0.91 0.58 2.40 1.88 4THREEWALL_1059 1000 1.98 5.1 286.67 0.91 0.58 2.40 1.88 3THREEWALL_1059 1000 1.98 5.4 244.2 0.91 0.58 2.40 1.88 3THREEWALL_1059 1000 1.98 5.7 207.16 0.91 0.58 2.40 1.88 3THREEWALL_1059 1000 1.98 6 186.73 0.91 0.58 2.40 1.88 2THREEWALL_1067 1000 1.14 2.4 663.06 1.22 0.94 2.53 2.01 18THREEWALL_1067 1000 1.14 2.7 440.84 1.22 1.22 2.53 2.01 24THREEWALL_1067 1000 1.14 3 343.31 1.22 1.38 2.53 2.01 24THREEWALL_1067 1000 1.14 3.3 279.81 1.22 1.5 2.53 2.01 24THREEWALL_1067 1000 1.14 3.6 235.01 1.22 1.66 2.53 2.01 25THREEWALL_1067 1000 1.14 3.9 190.95 1.22 1.74 2.53 2.01 24THREEWALL_1067 1000 1.14 4.2 167.89 1.22 1.82 2.53 2.01 23THREEWALL_1067 1000 1.14 4.5 141.24 1.22 1.82 2.53 2.01 21THREEWALL_1067 1000 1.14 4.8 125.62 1.22 1.98 2.53 2.01 21THREEWALL_1067 1000 1.14 5.1 112.94 1.22 1.86 2.53 2.01 18THREEWALL_1068 1000 1.98 3.6 659.45 1.22 0.7 2.53 2.01 6THREEWALL_1068 1000 1.98 3.9 496.14 1.22 0.78 2.53 2.01 7THREEWALL_1068 1000 1.98 4.2 397.07 1.22 0.82 2.53 2.01 7THREEWALL_1068 1000 1.98 4.5 318.85 1.22 0.78 2.53 2.01 5THREEWALL_1068 1000 1.98 4.8 272.29 1.22 0.74 2.53 2.01 4

E-162 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-9

Horizontal Plume Shift and Angle Sensitivity Results 

Test HRR (kW) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Diameter (m) RPO (m) RradThermoplastic (m) RradThermoset (m) Angle 

THREEWALL_1068 1000 1.98 5.1 234.15 1.22 0.78 2.53 2.01 4

THREEWALL_1068 1000 1.98 5.4 204.04 1.22 0.7 2.53 2.01 3THREEWALL_1068 1000 1.98 5.7 179.74 1.22 0.7 2.53 2.01 2THREEWALL_1068 1000 1.98 6 161.86 1.22 0.7 2.53 2.01 2

THREEWALL_850 50 1.14 2.4 155.3 0.30 0.46 0.58 0.46 14THREEWALL_851 100 1.14 2.4 255.53 0.30 0.46 0.77 0.60 14THREEWALL_851 100 1.14 2.7 139.25 0.30 0.7 0.77 0.60 20THREEWALL_857 50 1.98 2.4 415.6 0.30 0.26 0.58 0.46 17THREEWALL_857 50 1.98 2.7 235.48 0.30 0.34 0.58 0.46 16THREEWALL_857 50 1.98 3 157.34 0.30 0.38 0.58 0.46 14THREEWALL_857 50 1.98 3.3 111.29 0.30 0.46 0.58 0.46 14THREEWALL_858 100 1.98 2.7 510.25 0.30 0.34 0.77 0.60 16THREEWALL_858 100 1.98 3 327.37 0.30 0.38 0.77 0.60 14THREEWALL_858 100 1.98 3.3 218.83 0.30 0.38 0.77 0.60 11THREEWALL_858 100 1.98 3.6 169.87 0.30 0.42 0.77 0.60 10THREEWALL_858 100 1.98 3.9 135.33 0.30 0.42 0.77 0.60 8THREEWALL_915 200 1.14 2.4 300.06 0.61 0.7 1.16 0.93 19THREEWALL_915 200 1.14 2.7 159.86 0.61 0.94 1.16 0.93 23THREEWALL_915 200 1.14 3 134.36 0.61 1.1 1.16 0.93 24THREEWALL_916 300 1.14 2.4 488.54 0.61 0.66 1.36 1.08 17THREEWALL_916 300 1.14 2.7 250.02 0.61 0.9 1.36 1.08 22THREEWALL_916 300 1.14 3 174.28 0.61 1.02 1.36 1.08 22THREEWALL_916 300 1.14 3.3 141.38 0.61 1.14 1.36 1.08 22THREEWALL_916 300 1.14 3.6 123.99 0.61 1.26 1.36 1.08 22THREEWALL_916 300 1.14 3.9 110.29 0.61 1.34 1.36 1.08 21

E-163 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-9

Horizontal Plume Shift and Angle Sensitivity Results 

Test HRR (kW) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Diameter (m) RPO (m) RradThermoplastic (m) RradThermoset (m) Angle 

THREEWALL_917 400 1.14 2.4 663.59 0.61 0.62 1.53 1.20 16

THREEWALL_917 400 1.14 2.7 370.31 0.61 0.86 1.53 1.20 21THREEWALL_917 400 1.14 3 250.68 0.61 0.98 1.53 1.20 21THREEWALL_917 400 1.14 3.3 183.21 0.61 1.1 1.53 1.20 21THREEWALL_917 400 1.14 3.6 152.33 0.61 1.18 1.53 1.20 20THREEWALL_917 400 1.14 3.9 132.92 0.61 1.3 1.53 1.20 20THREEWALL_917 400 1.14 4.2 118.8 0.61 1.34 1.53 1.20 19THREEWALL_918 500 1.14 2.7 466.61 0.61 0.78 1.68 1.31 18THREEWALL_918 500 1.14 3 313.59 0.61 0.86 1.68 1.31 18THREEWALL_918 500 1.14 3.3 222.06 0.61 1.02 1.68 1.31 19THREEWALL_918 500 1.14 3.6 184.52 0.61 1.14 1.68 1.31 19THREEWALL_918 500 1.14 3.9 155.58 0.61 1.22 1.68 1.31 19THREEWALL_918 500 1.14 4.2 134.38 0.61 1.3 1.68 1.31 19THREEWALL_918 500 1.14 4.5 110.96 0.61 1.34 1.68 1.31 18THREEWALL_919 600 1.14 2.7 562.28 0.61 0.78 1.82 1.41 18THREEWALL_919 600 1.14 3 416.03 0.61 0.9 1.82 1.41 19THREEWALL_919 600 1.14 3.3 305.81 0.61 1.02 1.82 1.41 19THREEWALL_919 600 1.14 3.6 248 0.61 1.14 1.82 1.41 19THREEWALL_919 600 1.14 3.9 203.92 0.61 1.18 1.82 1.41 18THREEWALL_919 600 1.14 4.2 176.1 0.61 1.22 1.82 1.41 17THREEWALL_919 600 1.14 4.5 152.14 0.61 1.26 1.82 1.41 16THREEWALL_919 600 1.14 4.8 138.53 0.61 1.26 1.82 1.41 15THREEWALL_919 600 1.14 5.1 123.64 0.61 1.3 1.82 1.41 15THREEWALL_922 200 1.98 2.7 587.45 0.61 0.5 1.16 0.93 18THREEWALL_922 200 1.98 3 418.25 0.61 0.54 1.16 0.93 15

E-164 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-9

Horizontal Plume Shift and Angle Sensitivity Results 

Test HRR (kW) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Diameter (m) RPO (m) RradThermoplastic (m) RradThermoset (m) Angle 

THREEWALL_922 200 1.98 3.3 309.14 0.61 0.58 1.16 0.93 13

THREEWALL_922 200 1.98 3.6 236.87 0.61 0.62 1.16 0.93 12THREEWALL_922 200 1.98 3.9 183.85 0.61 0.62 1.16 0.93 10THREEWALL_922 200 1.98 4.2 148.83 0.61 0.62 1.16 0.93 9THREEWALL_922 200 1.98 4.5 125.65 0.61 0.62 1.16 0.93 8THREEWALL_923 300 1.98 3 706.09 0.61 0.54 1.36 1.08 15THREEWALL_923 300 1.98 3.3 490.62 0.61 0.58 1.36 1.08 13THREEWALL_923 300 1.98 3.6 368.3 0.61 0.58 1.36 1.08 11THREEWALL_923 300 1.98 3.9 270.83 0.61 0.62 1.36 1.08 10THREEWALL_923 300 1.98 4.2 210.29 0.61 0.62 1.36 1.08 9THREEWALL_923 300 1.98 4.5 162.55 0.61 0.62 1.36 1.08 8THREEWALL_923 300 1.98 4.8 137.83 0.61 0.62 1.36 1.08 7THREEWALL_923 300 1.98 5.1 120.83 0.61 0.62 1.36 1.08 6THREEWALL_924 400 1.98 3.3 661.79 0.61 0.58 1.53 1.20 13THREEWALL_924 400 1.98 3.6 499.42 0.61 0.58 1.53 1.20 11THREEWALL_924 400 1.98 3.9 368.24 0.61 0.58 1.53 1.20 9THREEWALL_924 400 1.98 4.2 286.26 0.61 0.58 1.53 1.20 8THREEWALL_924 400 1.98 4.5 226.33 0.61 0.58 1.53 1.20 7THREEWALL_924 400 1.98 4.8 193.8 0.61 0.58 1.53 1.20 6THREEWALL_924 400 1.98 5.1 163.16 0.61 0.58 1.53 1.20 6THREEWALL_924 400 1.98 5.4 137.27 0.61 0.58 1.53 1.20 5THREEWALL_924 400 1.98 5.7 117.47 0.61 0.62 1.53 1.20 5THREEWALL_925 500 1.98 3.3 779.73 0.61 0.54 1.68 1.31 12THREEWALL_925 500 1.98 3.6 644.76 0.61 0.54 1.68 1.31 9THREEWALL_925 500 1.98 3.9 498.6 0.61 0.54 1.68 1.31 8

E-165 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-9

Horizontal Plume Shift and Angle Sensitivity Results 

Test HRR (kW) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Diameter (m) RPO (m) RradThermoplastic (m) RradThermoset (m) Angle 

THREEWALL_925 500 1.98 4.2 385.1 0.61 0.58 1.68 1.31 8

THREEWALL_925 500 1.98 4.5 290.44 0.61 0.54 1.68 1.31 6THREEWALL_925 500 1.98 4.8 242.34 0.61 0.54 1.68 1.31 5THREEWALL_925 500 1.98 5.1 201.57 0.61 0.54 1.68 1.31 5THREEWALL_925 500 1.98 5.4 172.52 0.61 0.58 1.68 1.31 5THREEWALL_925 500 1.98 5.7 146.57 0.61 0.58 1.68 1.31 5THREEWALL_925 500 1.98 6 126.18 0.61 0.58 1.68 1.31 4THREEWALL_926 600 1.98 3.6 686.97 0.61 0.54 1.82 1.41 9THREEWALL_926 600 1.98 3.9 541.53 0.61 0.54 1.82 1.41 8THREEWALL_926 600 1.98 4.2 420.71 0.61 0.54 1.82 1.41 7THREEWALL_926 600 1.98 4.5 320.56 0.61 0.54 1.82 1.41 6THREEWALL_926 600 1.98 4.8 264.69 0.61 0.54 1.82 1.41 5THREEWALL_926 600 1.98 5.1 224.92 0.61 0.54 1.82 1.41 5THREEWALL_926 600 1.98 5.4 188.27 0.61 0.54 1.82 1.41 5THREEWALL_926 600 1.98 5.7 163.19 0.61 0.5 1.82 1.41 4THREEWALL_926 600 1.98 6 146.48 0.61 0.5 1.82 1.41 3THREEWALL_979 300 1.14 2.4 290.52 0.91 0.9 1.50 1.21 21THREEWALL_979 300 1.14 2.7 164.64 0.91 1.18 1.50 1.21 26THREEWALL_979 300 1.14 3 126.48 0.91 1.34 1.50 1.21 27THREEWALL_980 400 1.14 2.4 360.97 0.91 0.86 1.67 1.34 20THREEWALL_980 400 1.14 2.7 211.62 0.91 1.18 1.67 1.34 26THREEWALL_980 400 1.14 3 164.42 0.91 1.34 1.67 1.34 27THREEWALL_980 400 1.14 3.3 131.59 0.91 1.5 1.67 1.34 27THREEWALL_980 400 1.14 3.6 114.53 0.91 1.62 1.67 1.34 26THREEWALL_981 500 1.14 2.4 502.3 0.91 0.86 1.82 1.45 20

E-166 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-9

Horizontal Plume Shift and Angle Sensitivity Results 

Test HRR (kW) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Diameter (m) RPO (m) RradThermoplastic (m) RradThermoset (m) Angle 

THREEWALL_981 500 1.14 2.7 263.14 0.91 1.14 1.82 1.45 25

THREEWALL_981 500 1.14 3 203.96 0.91 1.34 1.82 1.45 27THREEWALL_981 500 1.14 3.3 167.48 0.91 1.46 1.82 1.45 26THREEWALL_981 500 1.14 3.6 143.06 0.91 1.54 1.82 1.45 25THREEWALL_981 500 1.14 3.9 126.31 0.91 1.62 1.82 1.45 24THREEWALL_981 500 1.14 4.2 113.8 0.91 1.66 1.82 1.45 22THREEWALL_982 600 1.14 2.4 584.51 0.91 0.86 1.95 1.55 20THREEWALL_982 600 1.14 2.7 330.93 0.91 1.14 1.95 1.55 25THREEWALL_982 600 1.14 3 248.81 0.91 1.3 1.95 1.55 26THREEWALL_982 600 1.14 3.3 201.1 0.91 1.42 1.95 1.55 25THREEWALL_982 600 1.14 3.6 173.38 0.91 1.54 1.95 1.55 25THREEWALL_982 600 1.14 3.9 151.54 0.91 1.62 1.95 1.55 24THREEWALL_982 600 1.14 4.2 133.52 0.91 1.7 1.95 1.55 23THREEWALL_982 600 1.14 4.5 118.27 0.91 1.78 1.95 1.55 22THREEWALL_986 300 1.98 2.7 661.25 0.91 0.66 1.50 1.21 20THREEWALL_986 300 1.98 3 470.11 0.91 0.66 1.50 1.21 14THREEWALL_986 300 1.98 3.3 333.3 0.91 0.7 1.50 1.21 13THREEWALL_986 300 1.98 3.6 258.73 0.91 0.7 1.50 1.21 10THREEWALL_986 300 1.98 3.9 207.21 0.91 0.74 1.50 1.21 10THREEWALL_986 300 1.98 4.2 162.1 0.91 0.74 1.50 1.21 9THREEWALL_986 300 1.98 4.5 128.46 0.91 0.74 1.50 1.21 8THREEWALL_987 400 1.98 3 656.43 0.91 0.7 1.67 1.34 16THREEWALL_987 400 1.98 3.3 421.27 0.91 0.7 1.67 1.34 13THREEWALL_987 400 1.98 3.6 319.87 0.91 0.74 1.67 1.34 12THREEWALL_987 400 1.98 3.9 246.42 0.91 0.7 1.67 1.34 9

E-167 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-9

Horizontal Plume Shift and Angle Sensitivity Results 

Test HRR (kW) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Diameter (m) RPO (m) RradThermoplastic (m) RradThermoset (m) Angle 

THREEWALL_987 400 1.98 4.2 200.39 0.91 0.74 1.67 1.34 9

THREEWALL_987 400 1.98 4.5 162.32 0.91 0.66 1.67 1.34 6THREEWALL_987 400 1.98 4.8 144.19 0.91 0.7 1.67 1.34 6THREEWALL_987 400 1.98 5.1 128.53 0.91 0.7 1.67 1.34 5THREEWALL_987 400 1.98 5.4 115.35 0.91 0.7 1.67 1.34 5THREEWALL_988 500 1.98 3 779.43 0.91 0.7 1.82 1.45 16THREEWALL_988 500 1.98 3.3 586.92 0.91 0.7 1.82 1.45 13THREEWALL_988 500 1.98 3.6 434.55 0.91 0.7 1.82 1.45 10THREEWALL_988 500 1.98 3.9 323.91 0.91 0.7 1.82 1.45 9THREEWALL_988 500 1.98 4.2 262.91 0.91 0.7 1.82 1.45 8THREEWALL_988 500 1.98 4.5 209.44 0.91 0.66 1.82 1.45 6THREEWALL_988 500 1.98 4.8 178.62 0.91 0.7 1.82 1.45 6THREEWALL_988 500 1.98 5.1 157.02 0.91 0.7 1.82 1.45 5THREEWALL_988 500 1.98 5.4 137.24 0.91 0.66 1.82 1.45 4THREEWALL_988 500 1.98 5.7 117.4 0.91 0.7 1.82 1.45 5THREEWALL_989 600 1.98 3.3 732.38 0.91 0.7 1.95 1.55 13THREEWALL_989 600 1.98 3.6 562.49 0.91 0.74 1.95 1.55 12THREEWALL_989 600 1.98 3.9 411.65 0.91 0.7 1.95 1.55 9THREEWALL_989 600 1.98 4.2 329.02 0.91 0.7 1.95 1.55 8THREEWALL_989 600 1.98 4.5 250.92 0.91 0.7 1.95 1.55 7THREEWALL_989 600 1.98 4.8 213.27 0.91 0.7 1.95 1.55 6THREEWALL_989 600 1.98 5.1 182.93 0.91 0.7 1.95 1.55 5THREEWALL_989 600 1.98 5.4 156.71 0.91 0.7 1.95 1.55 5THREEWALL_989 600 1.98 5.7 131.1 0.91 0.7 1.95 1.55 5THREEWALL_989 600 1.98 6 117.61 0.91 0.62 1.95 1.55 3

E-168 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
Table E-9

Horizontal Plume Shift and Angle Sensitivity Results 

Test HRR (kW) Source Height (m) Elevation (m) Maximum Plume Temperature Rise (C) Diameter (m) RPO (m) RradThermoplastic (m) RradThermoset (m) Angle 

OBST_1052 1000 1.14 2.7 619.49 0.91 0.46 2.40 1.88 2

OBST_1061 1000 1.14 2.4 668.56 1.22 0.66 2.53 2.01 5OBST_1061 1000 1.14 2.7 493.44 1.22 0.58 2.53 2.01 1

OBST_808 50 1.14 2.4 118.47 0.30 0.22 0.58 0.46 4OBST_815 50 1.98 2.4 218.53 0.30 0.22 0.58 0.46 11OBST_816 100 1.98 2.4 414.45 0.30 0.22 0.77 0.60 11OBST_874 300 1.14 2.4 348.65 0.61 0.42 1.36 1.08 7OBST_874 300 1.14 2.7 225.86 0.61 0.38 1.36 1.08 4OBST_876 500 1.14 2.4 650.82 0.61 0.38 1.68 1.31 5OBST_876 500 1.14 3 305.36 0.61 0.3 1.68 1.31 1OBST_938 400 1.14 2.4 325.72 0.91 0.58 1.67 1.34 8OBST_938 400 1.14 2.7 212.8 0.91 0.46 1.67 1.34 2OBST_940 600 1.14 3 272.81 0.91 0.42 1.95 1.55 0OBST_944 300 1.98 2.4 428.28 0.91 0.46 1.50 1.21 7OBST_945 400 1.98 2.4 614.19 0.91 0.46 1.67 1.34 7

E-169 ____________________________________________________________________________ 

OBSTRUCTED PLUME FIRE MODELING RESULTS
OBSTRUCTED PLUME FIRE MODELING RESULTS 

E-170 

Index to Obstructed and Unobstructed Simulation 

Numbers 

Table E-10 

Index to Obstructed and Unobstructed Simulation Numbers

HRR 

(kW) 

Source 

Height 

(m) 

Source 

Diameter 

(m) 

BASE_# 

(Unobstructed 

Plume) 

OBST_# 

(Top Plate 

Only) 

ARCH_# 

(Top Plate 

+ 2 Walls) 

THREEWALL_# 

(Top Plate + 3 

Walls) 

50 0.3048 0.3048 300 801 822 843 

50 1.1430 0.3048 311 808 829 850 

50 1.9812 0.3048 322 815 836 857 

100 0.3048 0.3048 301 802 823 844 

100 1.1430 0.3048 312 809 830 851 

100 1.9812 0.3048 323 816 837 858 

200 0.3048 0.6096 302 866 887 908 

200 1.1430 0.6096 313 873 894 915 

200 1.9812 0.6096 324 880 901 922 

300 0.3048 0.6096 303 867 888 909 

300 1.1430 0.6096 314 874 895 916 

300 1.9812 0.6096 325 881 902 923 

300 0.3048 0.9144 307 930 951 972 

300 1.1430 0.9144 318 937 958 979 

300 1.9812 0.9144 329 944 965 986 

400 0.3048 0.6096 304 868 889 910 

400 1.1430 0.6096 315 875 896 917 

400 1.9812 0.6096 326 882 903 924 

400 0.3048 0.9144 308 931 952 973 

400 1.1430 0.9144 319 938 959 980 

400 1.9812 0.9144 330 945 966 987 

500 0.3048 0.6096 305 869 890 911 

500 1.1430 0.6096 316 876 897 918 

500 1.9812 0.6096 327 883 904 925 

500 0.3048 0.9144 309 932 953 974 

500 1.1430 0.9144 320 939 960 981 

500 1.9812 0.9144 331 946 967 988 

600 0.3048 0.6096 306 870 891 912 

600 1.1430 0.6096 317 877 898 919 

600 1.9812 0.6096 328 884 905 926 

600 0.3048 0.9144 310 933 954 975 

600 1.1430 0.9144 321 940 961 982 

600 1.9812 0.9144 332 947 968 989 

1000 0.3048 0.9144 404 1051 1054 1057 

1000 1.1430 0.9144 400 1052 1055 1058 
OBSTRUCTED PLUME FIRE MODELING RESULTS 

E-171 

Table E-10 

Index to Obstructed and Unobstructed Simulation Numbers

HRR 

(kW) 

Source 

Height 

(m) 

Source 

Diameter 

(m) 

BASE_# 

(Unobstructed 

Plume) 

OBST_# 

(Top Plate 

Only) 

ARCH_# 

(Top Plate 

+ 2 Walls) 

THREEWALL_# 

(Top Plate + 3 

Walls) 

1000 1.9812 0.9144 401 1053 1056 1059 

1000 0.3048 1.2192 405 1060 1063 1066 

1000 1.1430 1.2192 402 1061 1064 1067 

1000 1.9812 1.2192 403 1062 1065 1068 
OBSTRUCTED PLUME FIRE MODELING RESULTS 

E-172 

Index to Opening Sensitivity Simulation Numbers 

Table E-11 

Index to Opening Sensitivity Simulation Numbers 

HRR (KW) OPENING (%) OBST_# ARCH_# THREEWALL_# 

200 14 1106 1107 1108 

600 12 1115 1116 1117 

200 10 1103 1104 1105 

600 10 1112 1113 1114 

200 6.5 1100 1101 1102 

600 7 1109 1110 1111 
F-1 

1 Appendix F

2 Examples of Enclosure Fire Analysis 

3 

4 This appendix includes two examples illustrating the process of applying guidance documented 

5 in this report. The examples cover the recommended process for classifying electrical 

6 enclosures that are selected as ignition sources for Fire PRA applications, assigning peak heat 

7 release rate probability distributions to such enclosures, and determining their corresponding 

8 zones of influence. 

9 

10 F.1 Example 1: Load Center Fire with Targets in the Fire 

11 Plume 

12 This example describes the process of assigning a peak heat release rate probability 

13 distribution to an electrical enclosure, determining the resulting severity factor, and defining the 

14 corresponding zone of influence. The example consists of the following steps: 

15 1. Scenario definition 

16 2. Classification of the electrical enclosure 

17 3. Determination of the peak heat release rate distribution 

18 4. Determination of the corresponding zone of influence 

19 5. Determination of the severity factor 

20 

21 The following sections describe each of the above listed steps in detail. 

22 

23 F.1.1 Description of the Scenario 

24 A fire is postulated in a load center cubicle (i.e., vertical section) located in a typical electrical 

25 room in a commercial nuclear power plant. The load center vertical section is 3 feet wide and 2 

26 feet deep. The height of the enclosure is 7 feet. The scenario is depicted in Figure F-1. 

27 

28 There are two cable trays in the room, and each of them contains target cables that are within 

29 the scope of the Fire PRA. The cables in trays T-1 and T-2 have thermoplastic jackets and 

30 insulation. Table H-1 in NUREG/CR-6850 recommends a value of 205°C (400°F) for 

temperature damage criteria and 6 kW/m2

 (0.5 BTU/ft2 31 s) for radiant heat damage criteria. 

32 

33 Cables of interest are in trays T-1 and T-2, which are located at 3 feet and 5 feet above the load 

34 center, respectively. These cable trays are exposed to fire plume conditions. Through 

35 inspection of the ignition source and cable tray layout during walkdowns and using plant 

36 drawings, the following scenario progression and target sets are evaluated: 

37 

38  Target Set 0: This scenario consists of a fire damaging only the load center. 

39  Target Set 1: This scenario consists of damage propagating outside the load center and 

40 damage the cable tray, T-1, above the electrical enclosure—that is, damage in the fire 

41 plume less than 5 feet above the electrical enclosure. In this scenario, T-2 also fails due 

42 to the fire propagating from cable tray T-1. 

43 

44 

45 
EXAMPLES OF ENCLOSURE FIRE ANALYSIS 

F-2 

1 

2 

3 

4 

5 

6 

7 

8 

9 

10 

11 

12 

13 

14 

15 

16 

17 

18 

19 

20 

21 

22 

23 Figure F-1 

24 Pictorial Representation of the Load Center Example

25 

26 F.1.2 Classification of the Electrical Enclosure 

27 The scenario consists of a load center. Since the load center is an electrical enclosure that has 

28 been primarily classified by its function, the classification of this electrical enclosure for the 

29 purposes of assigning a peak heat release rate probability distribution is straightforward. The 

30 load center is classified as “Switchgears and Load Centers” in Table 4-1 of this report. Figure 

31 F-1 depicts the load center as three cabinets. Cabinet to cabinet propagation is not considered 

32 in this example. 

33 F.1.3 Determination of Peak Heat Release Rate Probability 

34 Distributions 

35 Given the classification described in the previous section, the peak heat release rate probability 

36 distribution assigned to the load center is a Gamma with parameters Alpha = 0.99 and Beta = 

37 44. This is the distribution listed for load centers with thermoplastic cables in Table 4-1. This 

probability distribution has a 98th 38 percentile of 170 kW. Recall that the guidance in Chapter 8 of 

NUREG/CR-6850 recommends the use of the 98th 39 percentile as the value to use for screening 

40 purposes. 

41 F.1.4 Determination of the Zone of Influence 

The zone of influence generated by a fire in the load center is calculated using the 98th 42 

43 percentile of the peak heat release rate probability distribution as recommended in Chapter 8 

and Appendix F of NUREG/CR-6850. As indicated earlier in this example, the 98th 44 percentile 

45 value is 170 kW. 

46 

T-1

Load 

Center 

T-2
EXAMPLES OF ENCLOSURE FIRE ANALYSIS 

F-3 

1 Use the Heskestad plume temperature correlation for determining the vertical component of the 

2 zone of influence. Fire modeling analysts routinely use the Heskestad fire plume temperature 

3 correlation in support of Fire PRAs and other performance-based applications. Consequently, 

4 there are various practical implementations currently available for solving the correlation. Since 

5 this correlation is available within the NUREG 1805 library of programmed fire models (Chapter 

6 9 of NUREG-1805), perform the calculation using this available tool. 

7 

8 The zone of influence resulting from an unobstructed plume is calculated to be 6.25 feet. That 

9 is, using the following input parameters in the NUREG 1805 Chapter 9 spreadsheet: 

10 

11  Heat release rate: 170 kW; 

12  Elevation above the fuel source: 6.25 feet; 

 Area of the combustible fuel: 2 feet by 3 feet = 6 ft2 13 ; and 

 Ambient temperature: 77o 14 F. 

15 

results in a plume temperature of 201 o 16 C, which is conservative and sufficiently close to the 

17 damage criteria for thermoplastic cable. It should be noted that the following ambient and 

18 default values are also used throughout this example: 

19  Ambient air specific heat: 1.0 kJ/kg-K; 

 Ambient air density: 1.18 kg/m3 20 ; 

 Acceleration of gravity: 9.81 m/sec2 21 ; and 

22  Convective heat release rate fraction: 0.7. 

23 

24 Figure F-2 depicts the input block of the NUREG 1805 Chapter 9 spreadsheet model: 

25 

26 Figure F-2 

27 Input Parameters for Fire Plume Correlation in NUREG 1805, Chapter 9 Spreadsheet 

28 

29 Based on the guidance documented in Chapter 6 of this report, the vertical component of the 

30 zone of influence generated by obstructed plumes is reduced by 24%. In this example, the 

31 resulting vertical distance is 6.25 feet x 0.76 = 4.75 feet. Notice that the cable tray T-1 is 4 feet 

32 above the base of the fire, and therefore, cannot be screened. In this scenario, cable tray T-1 is 

33 both a target, as it contains “target cables”, and an intervening combustible. 

34 F.1.5 Determination of Severity Factors 

35 The severity factor is calculated following the process described in Chapter 8 and Appendices E 

36 and F of NUREG/CR-6850, but using the probability distributions and the obstructed plume 

37 modeling described in this report. Specifically: 

38 

39  The Heskestad fire plume correlation is used for determining the heat release rate 

necessary to generate a temperature of 205o 40 C at the location of the cable tray T-1. 

41 Refer to the resulting heat release rate as the “critical heat release rate”. Recall that the 

170.00

6.25

6.00

77.00

ft2

INPUT PARAMETERS

°F

Heat Release Rate of the Fire (Q)

Elevation Above the Fire Source (z)

kW

ft

Area of Combustible Fuel (Ac)

Ambient Air Temperature (Ta)
EXAMPLES OF ENCLOSURE FIRE ANALYSIS 

F-4 

1 separation between the top of the load center and the bottom of the cable tray T-1 is 3 

2 feet. The guidance in Chapter 12 of Supplement 1 of NUREG/CR-6850 suggests 

3 treating the base of the fire as 1 foot below the top of the cabinet; therefore the total 

4 separation is 4 feet. Cable tray T-2 will be subjected to a fire involving the electrical 

5 enclosure (i.e., the ignition source) and cable tray T-1. 

6  Using the probability distribution specified in the previous section, the severity factor is 

7 the area under the distribution to the right of the resulting critical heat release rate. In 

8 other words, the severity factor is the probability that the heat release rate of the 

9 electrical enclosure fire will exceed the critical heat release rate, given its probability 

10 distribution. 

11 

12 The input parameters, which are listed in Figure F-3, are used in the NUREG 1805 Chapter 9 

13 spreadsheet as follows: 

14 

15 Figure F-3 

16 Input Parameters for Fire Plume Correlation in NUREG 1805, Chapter 9 Spreadsheet 

17 

18 That elevation above the fire input parameter is entered as 4 feet, which accounts for the 

19 distance of 3 feet between the top of the electrical enclosure and the cable tray T-1 and the 

20 guidance in Chapter 12 of Supplement 1 of NUREG/CR-6850, which recommends postulating 

21 the fire 1 foot below the top of the enclosure. The area of the combustible fuel results from the 

multiplication of the width and depth of the cabinet, i.e., 3 feet x 2 feet = 6 ft2 22 . The ambient 

temperature is assumed to be 77 o 23 F for this example. 

24 The heat release rate input parameter is varied in the spreadsheet until the resulting plume 

temperature is approximately 205 ° 25 C, which is the damage criterion for thermoplastic cables. 

26 Alternatively the “goal seek” data tool, under the “What if Analysis” tab in Microsoft Excel, can 

be used to solve for the HRR directly, which will lead to a resulting value of 205 ° 27 C. In this case, 

28 a heat release rate value of 85kW results in a plume temperature 4 feet above the base of the 

fire of 204 ° 29 C. Therefore, the critical heat release rate is 85 kW. 

30 The severity factor resulting from a critical heat release rate of 85 kW can be readily obtained 

31 using the gamma distribution function in Microsoft Excel as follows: 

32 SF = 1-GAMMADIST(85,0.99,44,TRUE) = 0.14. 

33 Notice that the above analysis assumes an unobstructed fire plume generated by a fire 

34 postulated outside the electrical enclosure. At this point we can incorporate the “obstructed fire 

35 plume” approach described in Chapters 5 and 6 of this report. Recall from Chapters 5 and 6 that 

36 the obstructed plume is expected to have a temperature 38% lower than the equivalent 

37 unobstructed one. The NUREG 1805 calculation can then be altered using the obstructed plume 

38 method which is illustrated below to clearly illustrate the process. We will use the same terms as 

39 the above example but add an additional factor to account for the 38% reduction in temperature. 

40 The effective fire diameter D is calculated as 2.76 ft (0.84 m) for a burning area of 6 sq-ft. The 

41 distance above the base of the fire z remains as 4 ft (1.22 m). All default values listed earlier in 

42 the example remain constant but an additional term, “β”, is added to account for the 38% 

43 reduction in temperature as follows: 

85.00

4.00

6.00

77.00

ft2

INPUT PARAMETERS

°F

Heat Release Rate of the Fire (Q)

Elevation Above the Fire Source (z)

kW

ft

Area of Combustible Fuel (Ac)

Ambient Air Temperature (Ta)
EXAMPLES OF ENCLOSURE FIRE ANALYSIS 

F-5 

1 

∆ܶ ൌ ߚ ቌ9.1 ቈ ܶ଴

൫݃ܿ௣

଴ߩଶ

ଶ൯

቉

ଵ ଷൗ

ቍ ܳሶ

௖

ଶ ଷൗ ሺݖെݖ଴ሻ

ିହ

ଷൗ

2 

ݖ ଴ൌ െ1.02ܦ ൅ 0.083ܳሶ

ଶ ହൗ ൌ െ1.02ሺ0.84ሻ ൅ 0.083ሺ145ሻଶ ହൗ ൌ െ0.25

3 

ܶ ൌ 0.62 ቎ቌ9.1 ቈ 298.15

൫9.81	ሺ1.0ଶሻሺ1.18ଶሻ൯

቉

ଵ ଷൗ

ቍ ൫145ሺ0.7ሻ൯

ଶ ଷൗ ൫1.22 െ ሺെ0.25ሻ൯

ିହ

ଷൗ ൅ 25቏

4 

ܶ ൎ 0.62ሺ291.5ሻ ൅ 25 ൎ 205 o 5 C

6 The resulting critical heat release rate is calculated to be approximately 145 kW by solving the 

7 above equation. That is, a 145 kW fire generates plume temperatures of approximately 205 C 

8 4 ft above the base of the fire, which is the damage criterion for thermoplastic cables. With a 

9 heat release rate of 145 kW, the resulting severity factor is 

10 SF = 1-GAMMADIST(145,0.99,44,TRUE) = 0.04. 

11 The severity factor is only applied to the cable tray closest to the ignition source. Since cable 

12 tray T2 could be exposed to a fire involving the ignition source and cable tray T1, given this 

13 configuration, the analysts would need to determine if the resulting fire plume exposure from the 

14 ignition source and cable tray T1 can damage cable tray T2. If it is determined that the cable 

15 tray can be damaged, the fire propagation guidance in Appendix R of NUREG/CR-6850 can be 

16 used for determining the time to damage. 

17 F.1.6 Summary of Results 

18 This section summarizes the example results and provides a comparison between the methods 

19 and inputs recommended in NUREG/CR-6850 and the guidance provided in this report. The 

20 numerical results using inputs in NUREG/CR-6850 were calculated using the same process 

21 described earlier in this example. The gamma distribution for vertical cabinets with unqualified 

22 cables and fires limited to one cable bundle was selected for the load center (alpha = 1.6, beta = 

23 41.5). The results are summarized and compared in Table F-1. 

24 Table F-1 

25 Summary of Results from Example 1

NUREG/CR-6850 RACHELLE-FIRE 

(Unobstructed Plume)

RACHELLE-FIRE 

(Obstructed Plume) 

Peak HRR 

Probability 

Distribution 

98th

Percentiles 

(kW) 

Vertical 

ZOI (ft) 

Resulting 

Severity 

Factor 

Peak HRR 

Probability 

Distribution 

98th

Percentiles 

(kW) 

Vertical 

ZOI (ft) 

Resulting 

Severity 

Factor 

Vertical ZOI 

(ft) 

Resulting 

Severity Factor 

211 kW 7.0 0.28 170 6.25 0.14 4.75 0.04 

26 

27 
EXAMPLES OF ENCLOSURE FIRE ANALYSIS 

F-6 

1 F.2 Example 2 – Application of RACHELLE_FIRE to Realistic 

2 Plant Analysis Units 

3 This example is a limited pilot application of the results presented in RACHELLE_FIRE to 

4 realistic plant configurations from actual Plant Analysis Units (PAU) and addresses impacts and 

5 issues that may arise when evaluating fire scenarios. The steps for this example include: 

6 

7 1) Selection of compartments to analyze 

8 2) Identification of applicable ignition sources 

9 3) Identification of applicable heat release rates (HRR) 

10 4) Determination of appropriate zones of influence (ZOI) 

11 5) Selection of targets 

12 6) Determination of severity factors 

13 7) Determination of CDF* 

14 

15 Steps 3 through 7 will be repeated for several cases in order to allow for review and comparison 

16 of results for insights on the effectiveness and potential limitations of the guidance. Each case 

17 will include the evaluation of all of the selected scenarios in each PAU. The methodology to 

18 perform the fire modeling steps follows that described in Example 1. The cases being analyzed 

19 are: 

20 

Case Description 

1 NUREG/CR-6850 guidance without significant refinement 

2 NUREG/CR-6850 guidance (including supplemental guidance) with refinement 

of fire size and refined target selection 

3 Same as Case 2 except RACHELLE_FIRE HRRs applied 

4 Same as Case 2 except RACHELLE_FIRE HRRs applied with vertical ZOI 

adjusted to account for obstructed plume 

5 Same as Case 4 except some RACHELLE_FIRE HRRs revised based on 

cabinet internals inspection 

21 

22 An additional case was also included to compare the benefits of RACHELLE_FIRE to benefits 

23 of potential modifications. 

24 

Case Description 

2a Same as Case 2 with automatic suppression credited in the compartment 

25 

26 * Scenario ignition frequencies, manual non-suppression probabilities and CCDPs are 

27 calculated using common practice; however, the details of that analysis are not included as a 

28 part of this example. The exact same methods are used for all cases. CDF is presented for 

29 evaluation of risk insights and is based on the generic equation where: 

30 

31 CDF = IGF * NSP * CCDP 

32 

33 It is noted that the purpose of this example is not to illustrate the fire modeling calculations, but 

34 to show the potential impacts of applying the new guidance given in this report to realistic plant 

35 configurations. Example 1 provides a general demonstration for the specific fire modeling 

36 calculations. 

37 
EXAMPLES OF ENCLOSURE FIRE ANALYSIS 

F-7 

1 F.2.1 Selection of Compartments for Analysis 

2 For this example, three locations (PAUs) have been selected at a plant based on the type of 

3 cabinets present and overall risk significance, to demonstrate the application and potential risk 

4 impact by applying the new guidance presented in this report. The three locations selected are 

5 shown in Figures F-4, F-5, and F-6 as fire compartments A, B, and C, respectively. All of the 

6 fire compartments can be assumed to have 3-hour fire rated walls and full room ionizing fire 

7 detection installed. None of the compartments are occupied or have automatic suppression 

8 systems. A general description for each location is as follows: 

9 

Compartment Description 

A The compartment contains equipment primarily associated with rod 

control. It has a floor area of approximately 850 square feet and a 

ceiling height of 11 feet. The targets in this room consist of both 

conduits and cable trays. 

B The compartment is adjacent to the main control room and contains 

primarily process control cabinets. It has a floor area of 

approximately 600 square feet and a ceiling height of 11 feet. 

There are a significant number of cable trays in this location. 

C This compartment is a battery room containing both trains of station 

batteries and related electrical cabinets. It has a floor area of 

approximately 500 square feet and a ceiling height of 12 feet. 

There are several cable tray stacks primarily located on the back 

and side walls in addition to conduit targets. 

10 

11 F.2.2 Selection of Sources for Analysis 

12 Only the unscreened (unscreened cabinets include those which are not considered small and 

13 well sealed) electrical cabinet sources (reference NUREG/CR-6850 Bin 15) are included in this 

14 example. Each selected source is assigned a source number. The source locations are 

15 identified in each compartment in Figures F-4, F-5, and F-6. The sources are also listed in 

16 Table F-2. A source description and basic source dimensions are also included. 

17 Compartments A and B contain primarily control cabinets whereas compartment C is power 

18 cabinets. 

19 F.2.3 Evaluation of Individual Cases 

20 Each case is evaluated using the same process. The process consists of selecting the 

21 applicable HRR(s) for the ignition sources, developing the scenarios, and quantifying the risk. 

22 The scenario development in this example is based on calculating the ZOI for the selected HRR 

23 and selecting targets within the ZOI. A severity factor is also calculated based on the distance 

24 to the nearest target (see Example 1 for details of determining severity factors and ZOI). If the 

25 target set includes secondary combustibles, such as exposed cables, propagation is assumed 

26 and additional targets are included in the set. 
EXAMPLES OF ENCLOSURE FIRE ANALYSIS 

F-8 

1 Table F-2 Source List

Source ID Description

Source  Dimens. (in) Area Volume

Length Width Height ft2 ft3

A_0312 CABINET #312 32 48 96 10.67 85.3

A_0314 DC HOLD CABINET 50 45 98 15.63 127.6

A_0315 LOGIC CABINET 50 45 98 15.63 127.6

A_0316 POWER CABINET – 2BD 24 83 98 13.83 113.0

A_0317 POWER CABINET – 2AC 24 83 98 13.83 113.0

A_0318 POWER CABINET – 1BD 24 83 78 13.83 89.9

A_0319 POWER CABINET – 1AC 24 83 98 13.83 113.0

A_0320 CORE EXIT THERMOCOUPLE CABINET 30 30 96 6.25 50.0

A_0321 IMPACT MONITORING SYSTEM CABINET 30 26 90 5.42 40.6

B_0337 CABINET #14 32 22 84 4.89 34.2

B_0338 CABINET #15 32 22 84 4.89 34.2

B_0339 CABINET #16 32 22 84 4.89 34.2

B_0340 CABINET #17 32 22 84 4.89 34.2

B_0341 CABINET #18 32 22 84 4.89 34.2

B_0343 CABINET #19 32 22 84 4.89 34.2

B_0344 CABINET #20 32 22 84 4.89 34.2

B_0345 CABINET #21 32 22 84 4.89 34.2

B_0346 CABINET #22 32 22 84 4.89 34.2

B_0347 CABINET #28 32 22 84 4.89 34.2

B_0348 CABINET #23 32 22 84 4.89 34.2

B_0349 CABINET #24 32 22 84 4.89 34.2

B_0350 CABINET #25 32 22 84 4.89 34.2

B_0352 CABINET #1 32 22 84 4.89 34.2

B_0353 CABINET #2 32 22 84 4.89 34.2

B_0354 CABINET #3   32 22 84 4.89 34.2

B_0356 CABINET #4 32 22 84 4.89 34.2

B_0357 CABINET #5 32 22 84 4.89 34.2

B_0358 CABINET #6 32 22 84 4.89 34.2

B_0359 CABINET #7 32 22 84 4.89 34.2

B_0360 CABINET #8 32 22 84 4.89 34.2

B_0361 CABINET #9 32 22 84 4.89 34.2

B_0362 CABINET #10 32 22 84 4.89 34.2

B_0363 CABINET #11 32 22 84 4.89 34.2

B_0364 CABINET #12 32 22 84 4.89 34.2

C_0183 BATTERY CHARGER – A 36 46 68 11.50 65.2

C_0184 BATTERY CHARGER – A‐1 36 46 68 11.50 65.2

C_0185 MCC‐A 20 40 90 5.56 41.7

C_0186 MCC‐B 57 19 90 7.52 56.4

C_0188 BATTERY CHARGER – B‐1 46 36 68 11.50 65.2

C_0189 BATTERY CHARGER – B 46 36 68 11.50 65.2
EXAMPLES OF ENCLOSURE FIRE ANALYSIS 

F-9 

1 

2 

3 

4 

5 Figure F-4 

6 Fire Compartment A 

7 

0

3

0

3

0

3

0

3

0315 

0314 

0320

0321

0312
EXAMPLES OF ENCLOSURE FIRE ANALYSIS 

F-10 

1 

2 Figure F-5 

3 Fire Compartment B 

4 

0337

0338

0339

0340

0341

0343

0344

0345

0346

0347

0348

0349

0350

0353 

0352 

0354 

0356 

0357 

0358

0359 

0360 

0361 

0362 

0363

0364 
EXAMPLES OF ENCLOSURE FIRE ANALYSIS 

F-11 

1 

2 Figure F-6 

3 Fire Compartment C 
EXAMPLES OF ENCLOSURE FIRE ANALYSIS 

F-12 

1 Each scenario also evaluates fire growth and potential hot gas layer (HGL) development based 

2 on the room configuration. If suppression is unsuccessful when HGL conditions are met, all 

3 targets in the compartment are assumed failed. The details of this analysis are not part of this 

4 example, however the methods are consistent with common practice. It should also be noted 

that the 98th 5 percentile HRR should always be used for screening, however selection of 

6 scenarios and additional points from the HRR distribution to evaluate is based on the judgment 

7 of the analyst as needed to achieve more realistic results. 

8 The results for each case include the HRRs selected, severity factors, HRR ZOIs, the number of 

9 targets in the ZOIs, the total CDF for the source, and the percentage of the CDF due to HGL 

10 conditions. The total CDF includes contribution from all evaluated scenarios for the source. 

11 

12 The following notes provide specific information to assist in assessing the data provided in 

13 Tables F-3 through F-7. 

14 

15 1. The cabling within the cabinets is IEEE-383 qualified or equivalent. 

16 2. The plant is comprised primarily of thermoplastic cables. Thermoplastic damage criteria 

are used; radiant heating damage criterion is 6 kW/m2

 (0.5 BTU/ft2 17 s); temperature 

18 damage criterion is 205°C (400°F). 

19 3. Source to target distances were initially measured from the top and sides of the cabinet. 

20 The radial distance was used to determine the nearest target. 

21 4. A distance to first target of “NA” is an indicator that there were no external targets in the 

22 calculated ZOI. 

23 F.2.3.1 Case 1 

24 

25 Case 1 defines an ignition source level analysis using methods based on NUREG/CR-6850. 

Each electrical cabinet is fire modeled using the 98th 26 percentile HRR as a screening value, and 

27 the ZOIs are based on a bounding fire size located at the top of the cabinet as determined for 

28 initial source walkdowns to identify target sets. The target sets include all potential 

29 combustibles (e.g., cables, trays, raceways, conduits, etc.) observed in the ZOIs. 

30 

31 The electrical cabinet sources in each compartment are listed in Table F-2. Table F-3 includes 

32 additional information specific to Case 1. This includes the assigned HRR, SF, number of 

33 targets (raceways) in the zone of influence (ZOI), core damage frequency (CDF) and the 

34 percentage of the CDF that is due to HGL conditions. 

35 

36 1. HRRs were determined using NUREG/CR-6850, Table G-1: 

37 a. Case 1: Vertical cabinets with qualified cable, fire limited to one cable bundle; 

75th is 69 kW, 98th 38 is 211 kW 

39 b. Case 2: Vertical cabinets with qualified cable, fire in more than one cable bundle; 

75th is 211 kW, 98th 40 is 702 kW 
EXAMPLES OF ENCLOSURE FIRE ANALYSIS 

F-13 

1 2. Vertical ZOI (Elevation Above the Fire Source (z)) was calculated using NUREG-1805, 

Fire Dynamics Tools (FDTs 2 ), Chapter 9, Estimating Centerline Temperature of a Buoyant 

3 Fire Plume, with the following input parameters: 

4 Heat Release Rate of the Fire (Q): Varies, see item 1 

5 Ambient Air Temperature (Ta): 77°F 

6 Specific Heat of Air (cp): 1.00 kJ/kg-K 

Ambient Air Density (ρa): 1.18 kg/m3 7 

Acceleration of Gravity (g): 9.81 m/sec2 8 

9 Convective Heat Release Fraction (χc): 0.70 

Area of Combustible Fuel (Ac): 1.0 ft2 10 

11 The inputs described above need to be evaluated to ensure that the methods used were 

12 applied within the verification and validation (V&V) range of applicability as defined in 

13 NUREG-1824. 

Froude Number: The 1.0 ft2 14 value for the area of the fuel was selected to bound all 

15 larger fuel packages. This yields an effective diameter (D) of 1.1 ft (0.34 m). The 

Froude Number, ܳሶ

∗ 16 , is used to determine if the heat release rate relative to the diameter 

17 of the fire scenario is within the range of HRR that is within the scope of NUREG-1824 

18 (acceptable range 0.4-2.4). It is calculated using the following equation (NUREG-1934, 

19 Equation 2-4): 

ܳሶ

∗ ൌ ܳሶ

ܦ݃ଶඥܦ௔ܶ௣ܿ௔ߩ

20 Flame Height Ratio: The flame length ratio, Lf/Hf, is used to determine if the flame height 

21 relative to the upper horizontal boundary of the fire scenario is within the range of HRR 

22 that is within the scope of NUREG-1824 (acceptable range 0.2-1.0). The equation for the 

23 calculation of this parameter is the following (NUREG-1934, Equation 2-6): 

݈௙ ൌ ܦ ൬3.7 ൈ ܳሶ

∗

ଶ

ହ െ 1.02൰

HRR Froude Height of Target Flame 

Height 

Flame 

Length Ratio 

Q* Ht (ft) Ht (m) Lf (m) Lf/Hf

69 0.90 5.11 1.56 0.87 0.56 

211 2.76 8.56 2.61 1.56 0.60 

702 9.19 14.70 4.48 2.74 0.61 

24 

25 The vertical ZOI calculations for the Fire Froude number present an “out of range” result. 

26 The “out of range” case is due to the calculation exceeding the upper limit of the range, 

27 suggesting a high intensity fire for the selected fire diameter. One reason for exceeding 
EXAMPLES OF ENCLOSURE FIRE ANALYSIS 

F-14 

the upper limit is the use of the 98th 1 percentile heat release rates for the corresponding 

fire diameters. Based on the guidance in Chapter 8 of NUREG/CR-6850, 98th 2 percentile 

3 heat release rate values are used for screening and can be considered on the high end 

4 of the values assigned to ignition sources. In addition, setting the Froude number 

calculation to the upper range limit of 2.4 for the 98th 5 percentile heat release rate values 

6 would result in a larger diameter. With a larger diameter, the flame height calculation 

7 would result in shorter flame lengths, and plume temperature calculations would suggest 

8 lower temperatures. The “out of range” results are based on conservative ZOI 

9 calculations for the Fire PRA. 

10 3. Horizontal ZOI (Distance between Fire and Target (L)) was calculated using NUREG1805, Fire Dynamics Tools (FDTs 11 ), Chapter 5.1, Estimating Radiant Heat Flux from Fire 

12 to a Target Fuel at Ground Level Under Wind-Free Conditions, Solid Flame Radiation 

13 Model 2, with the following input parameters: 

14 Heat Release Rate of the Fire (Q): Varies, see item 1 

Fuel Area or Dike Area (Adike): 6.0 ft2 15 (reference ML12146A439) 

16 Vertical Distance of Target from Ground (H1): User defined increments for each 

17 HRR such that the mid-height level 

18 of the flame, where radiation effects 

19 are maximized, was used. 

20 Once again, the inputs described above need to be evaluated to ensure that the 

21 methods used were applied within the verification and validation (V&V) range of 

22 applicability as defined in NUREG-1824. 

Froude Number: The 6.0 ft2 23 value for the area of the fuel was selected to bound all 

24 larger fuel packages. This yields an effective diameter (D) of 2.8 ft (0.84 m). The 

Froude Number, Qሶ∗ 25 , (acceptable range 0.4-2.4) again is used to determine if the heat 

26 release rate relative to the diameter of the fire scenario is within the range of HRR that is 

27 within the scope of NUREG-1824. It is calculated using the equation presented above.

28 Radial Distance Ratio: The Radial Distance Ratio, r/D, is used to determine if the 

29 horizontal radial distance from the fire to the target is within the range of distances 

30 included in NUREG-1824 (acceptable range 2.2-5.7). The Horizontal Distance between 

31 Target and Center of Fire, r, is defined as: 

൅ܮൌݎ

ܦ

2

32 
EXAMPLES OF ENCLOSURE FIRE ANALYSIS 

F-15 

HRR Froude Distance between 

Fire and Target 

Horizontal Distance 

between Target and 

Center of Fire 

Radial 

Distance Ratio 

Q* L (ft) L (m) r (m) r/D 

69 0.10 2.59 0.79 1.21 1.44 

211 0.29 4.56 1.39 1.81 2.15 

702 0.98 6.57 2.00 2.42 2.88 

1 

2 The horizontal component refers mostly to flame radiation for targets located near the 

3 flames. Consequently, ZOI calculations for the Fire Froude number are mostly “out of 

4 range” as they are based on experiments where the radiation was measured at some 

5 longer distance from the flames. The “out of range” results for the Fire Froude number 

6 are therefore expected given that the ZOI calculations define a region close to the 

7 flames. However, it should be noted that the Fire Froude Number is not the key 

8 parameter recommended for flame radiation scenarios. Table 2-5 of NUREG-1934 

9 recommends the use of the radial distance ratio dimensionless parameter for radiation 

10 heat flux applications. 

11 For the radial distance ratio dimensionless parameter, all the calculations that are “out of 

12 range” are on the low side of the range, suggesting again that the ZOI is characterized 

13 by distances close to the flames. These calculations were conducted with the solid flame 

14 radiation model described in Chapter 5.2 of NUREG-1805. A review of Figure 6-8 in 

15 Volume 3 of NUREG-1824 suggests that the majority of the validation results (with a few 

exceptions for Cable G in radiation ranges larger than the 6 kW/m2 16 for ZOI calculations) 

17 suggest over-predictions of the flame radiation, which would result in longer horizontal 

18 distances for the ZOI. Table 4-1 in NUREG-1934 suggests an average prediction of 2.02 

19 times greater than experimental values for radiant heat flux calculations using FDTs. 

20 In summary, the reason for the number of ZOI results that are “out of range” is because 

21 the ZOI distances are close to the flames, and the experiments selected for validation 

22 purposes measured radiation at longer distances from the flames. This is a limitation on 

23 the available data for validation and not necessarily a limitation on the use of the solid 

24 flame radiation model for calculating horizontal components of the ZOI for Fire PRA 

25 applications. To account for this limitation, it is noted that validation results from Figure 

26 6-8 in Volume 3 of NUREG-1824 indicate significant heat flux over-predictions over the 

intensity levels used for ZOI calculations (i.e., between 6 and 11 kW/m2 27 ) that would 

28 result in longer, and therefore conservative, horizontal distances. 

29 4. Severity factor is developed using the same methods as discussed in Appendix F.1.5 of 

30 Example 1. 

31 5. Based on the results provided in Table F-3 there is a varying degree of risk associated 

32 with the electrical cabinets in each compartment. There is also a significant potential for 

33 HGL conditions to develop. The initial results indicate that additional refinements should 

34 be investigated. 

35 
Table F-3 1 

Cabinet List with NUREG/CR-6850 Based HRR (Case 1) 2 

3 

Area Volume 6850 HRR To First Target

Length Width Height ft2 ft3 98th Horizontal Vertical inches

A_0312 CABINET #312 32 48 96 10.7 85.3 211 55 104 32 0.648 3 0 0.00E+00 0.0%A_0314 DC HOLD CABINET 50 45 98 15.6 127.6 702 79 176 29 0.828 20 5 9.26E-07 98.2%A_0315 LOGIC CABINET 50 45 98 15.6 127.6 702 79 176 29 0.828 20 5 1.02E-06 98.4%A_0316 POWER CABINET – 2BD 24 83 98 13.8 113.0 702 79 176 35 0.786 5 0 0.00E+00 0.0%A_0317 POWER CABINET – 2AC 24 83 98 13.8 113.0 702 79 176 29 0.828 30 8 4.12E-06 32.5%A_0318 POWER CABINET – 1BD 24 83 78 13.8 89.9 702 79 176 32 0.807 10 0 1.12E-08 0.0%A_0319 POWER CABINET – 1AC 24 83 98 13.8 113.0 702 79 176 30 0.821 34 8 2.10E-06 31.7%A_0320 CORE EXIT THERMOCOUPLE CABINET 30 30 96 6.3 50.0 702 79 176 N/A 0.000 4 0 0.00E+00 0.0%A_0321 IMPACT MONITORING SYSTEM CABINET 30 26 90 5.4 40.6 211 55 104 8 0.917 3 0 0.00E+00 0.0%B_0337 CABINET #14 32 22 84 4.9 34.2 702 79 176 5 0.958 37 12 7.93E-07 4.3%B_0338 CABINET #15 32 22 84 4.9 34.2 702 79 176 5 0.958 34 12 7.93E-07 4.3%B_0339 CABINET #16 32 22 84 4.9 34.2 702 79 176 5 0.958 33 12 1.05E-07 32.4%B_0340 CABINET #17 32 22 84 4.9 34.2 702 79 176 5 0.958 29 12 3.53E-08 96.3%B_0341 CABINET #18 32 22 84 4.9 34.2 702 79 176 5 0.958 25 12 3.53E-08 96.3%B_0343 CABINET #19 32 22 84 4.9 34.2 702 79 176 5 0.958 24 12 3.55E-08 95.7%B_0344 CABINET #20 32 22 84 4.9 34.2 702 79 176 5 0.958 22 12 3.59E-08 94.7%B_0345 CABINET #21 32 22 84 4.9 34.2 702 79 176 5 0.958 21 11 3.43E-08 99.3%B_0346 CABINET #22 32 22 84 4.9 34.2 702 79 176 5 0.958 21 11 3.40E-08 99.9%B_0347 CABINET #28 32 22 84 4.9 34.2 702 79 176 5 0.958 19 11 3.40E-08 99.9%B_0348 CABINET #23 32 22 84 4.9 34.2 702 79 176 5 0.958 19 11 3.53E-08 96.3%B_0349 CABINET #24 32 22 84 4.9 34.2 702 79 176 5 0.958 15 11 3.53E-08 96.3%B_0350 CABINET #25 32 22 84 4.9 34.2 702 79 176 5 0.958 13 11 3.53E-08 96.3%B_0352 CABINET #1 32 22 84 4.9 34.2 702 79 176 5 0.958 26 5 1.82E-08 92.6%B_0353 CABINET #2 32 22 84 4.9 34.2 702 79 176 5 0.958 22 5 1.82E-08 92.6%B_0354 CABINET #3 32 22 84 4.9 34.2 702 79 176 5 0.958 21 5 1.82E-08 92.8%B_0356 CABINET #4 32 22 84 4.9 34.2 702 79 176 5 0.958 15 5 1.84E-08 91.6%B_0357 CABINET #5 32 22 84 4.9 34.2 702 79 176 5 0.958 12 5 1.84E-08 91.6%B_0358 CABINET #6 32 22 84 4.9 34.2 702 79 176 5 0.958 14 5 1.95E-08 86.4%B_0359 CABINET #7 32 22 84 4.9 34.2 702 79 176 5 0.958 19 7 2.79E-08 94.5%B_0360 CABINET #8 32 22 84 4.9 34.2 702 79 176 5 0.958 18 5 1.88E-08 89.8%B_0361 CABINET #9 32 22 84 4.9 34.2 702 79 176 5 0.958 17 5 1.84E-08 91.6%B_0362 CABINET #10 32 22 84 4.9 34.2 702 79 176 5 0.958 17 5 1.71E-08 98.5%B_0363 CABINET #11 32 22 84 4.9 34.2 702 79 176 5 0.958 17 5 1.84E-08 91.5%B_0364 CABINET #12 32 22 84 4.9 34.2 702 79 176 5 0.958 15 5 1.82E-08 92.6%C_0183 BATTERY CHARGER – A 36 46 68 11.5 65.2 211 55 104 15 0.854 11 4 7.16E-07 77.5%C_0184 BATTERY CHARGER – A-1 36 46 68 11.5 65.2 211 55 104 7 0.924 20 5 1.06E-06 83.5%C_0185 MCC-A 20 40 90 5.6 41.7 211 55 104 N/A 0.000 3 0 1.18E-07 0.0%C_0186 MCC-B 57 19 90 7.5 56.4 211 55 104 N/A 0.000 4 1 1.99E-08 0.0%C_0188 BATTERY CHARGER – B-1 46 36 68 11.5 65.2 211 55 104 10 0.900 7 3 1.91E-07 97.4%C_0189 BATTERY CHARGER – B 46 36 68 11.5 65.2 211 55 104 40 0.538 3 2 1.82E-09 0.0%

Source ID Description Source Dimens. (in) % HGL CDF SF 98th # Targets 98th # Trays 98th ZOI (in)

____________________________________________________________________________ 

EXAMPLES OF ENCLOSURE FIRE ANALYSIS

F-16
EXAMPLES OF ENCLOSURE FIRE ANALYSIS 

F-17 

1 F.2.3.2 Case 2 

2 

3 For Case 2 the scenarios were refined in several ways. First, a second HRR was selected at 

the 75th 4 percentile from the distribution. For quantification, a two point model was used where 

10% of the ignition frequency was applied to the 98th 5 percentile HRR and 90% was applied to 

the 75th 6 percentile HRR. Also, a more realistic fire size using actual cabinet dimensions was 

7 applied, and the fire was placed at one foot below the top of the cabinet in accordance with FAQ 

8 08-0043, “Location of Fires Within Electrical Cabinets”. Finally, the cable tray targets were 

9 reviewed to more realistically address propagation and fire growth. Table F-4 provides the 

10 updated data and results. This case represents a baseline to compare the impacts of applying 

11 revised HRRs from RACHELLE_FIRE (Cases 3, 4, and 5) 

12 

1. The 98th 13 percentile HRRs for each cabinet are the same as in Case 1. 

2. Vertical ZOI (z) is calculated using NUREG-1805, Fire Dynamics Tools (FDTs 14 ), Chapter 

15 9, Estimating Centerline Temperature of a Buoyant Fire Plume, with the same input 

16 parameters as Case 1, with the exception of the Area of Combustible Fuel (Ac). 

17 The Froude Number is evaluated for each cabinet to ensure that the value for the area of 

18 the fuel is within its V&V range of applicability (acceptable range 0.4-2.4). For cabinets 

19 where the Fire Froude number is “out of range” on the upper bound, the area of the fuel 

20 was adjusted (diameter decreased) to correspond to the maximum acceptable Froude 

21 Number. For “out of range” cases below the acceptable range, the actual cabinet 

22 dimension was used. This ensures that the results for each vertical ZOI case remain 

23 applicable and conservative. 

3. Horizontal ZOI (L) was calculated using NUREG-1805, Fire Dynamics Tools (FDTs 24 ), 

25 Chapter 5.1, “Estimating Radiant Heat Flux from Fire to a Target Fuel at Ground Level 

26 Under Wind-Free Conditions, Solid Flame Radiation Model 2”, with the same input 

27 parameters as Case 1, with the exception of the Area of Combustible Fuel (Ac). 

28 Once again, the Froude Number is evaluated for each cabinet to ensure that the value 

29 for the area of the fuel is within its V&V range of applicability (acceptable range 0.4-2.4). 

30 For cabinets where the Fire Froude number is “out of range” on the upper bound, the 

31 area of the fuel was adjusted (diameter decreased) to correspond to the maximum 

32 acceptable Froude Number. For “out of range” cases below the acceptable range, the 

33 actual cabinet dimension was used. This ensures that the results for each vertical ZOI 

34 case remain applicable and conservative. 

35 4. Severity factor is developed using the same methods as discussed in Appendix F.1.5 of 

36 Example 1. 

37 

38 
Table F-4 Cabinet List with NUREG/CR-6850 Based HRR and Scenario Refinements 1 

2 

To First Target

75th 98th Horizontal Vertical Horizontal Vertical inches

A_0312 CABINET #312 69 211 34 56 54 88 44 0.299 3 3 0 0 0.00E+00 0.0%A_0314 DC HOLD CABINET 211 702 54 88 86 142 41 0.478 13 20 3 5 1.58E-07 96.5%A_0315 LOGIC CABINET 211 702 54 88 86 142 41 0.478 20 20 5 5 3.09E-07 97.4%A_0316 POWER CABINET – 2BD 211 702 54 88 86 142 46 0.440 4 5 0 0 0.00E+00 0.0%A_0317 POWER CABINET – 2AC 211 702 54 88 86 142 41 0.478 25 30 7 8 1.74E-06 25.6%A_0318 POWER CABINET – 1BD 211 702 54 88 86 142 42 0.471 10 10 0 0 4.87E-09 0.0%A_0319 POWER CABINET – 1AC 211 702 54 88 86 142 40 0.486 25 34 5 8 9.11E-07 19.0%A_0320 CORE EXIT THERMOCOUPLE CABINET 211 702 54 88 80 156 N/A 0.000 4 4 0 0 0.00E+00 0.0%A_0321 IMPACT MONITORING SYSTEM CABINET 69 211 34 56 54 88 19 0.620 3 3 0 0 0.00E+00 0.0%B_0337 CABINET #14 211 702 54 88 76 160 17 0.802 24 37 4 4 6.74E-08 11.0%B_0338 CABINET #15 211 702 54 88 76 160 17 0.802 29 34 4 4 6.74E-08 11.0%B_0339 CABINET #16 211 702 54 88 76 160 17 0.802 26 33 4 4 1.41E-08 52.5%B_0340 CABINET #17 211 702 54 88 76 160 17 0.802 23 29 4 4 8.70E-09 85.0%B_0341 CABINET #18 211 702 54 88 76 160 17 0.802 20 25 4 4 8.70E-09 85.0%B_0343 CABINET #19 211 702 54 88 76 160 17 0.802 18 24 4 4 8.72E-09 84.9%B_0344 CABINET #20 211 702 54 88 76 160 17 0.802 14 22 4 4 9.19E-09 80.5%B_0345 CABINET #21 211 702 54 88 76 160 17 0.802 13 21 4 4 7.43E-09 99.6%B_0346 CABINET #22 211 702 54 88 76 160 17 0.802 14 21 4 4 7.41E-09 99.8%B_0347 CABINET #28 211 702 54 88 76 160 17 0.802 12 19 4 4 7.41E-09 99.8%B_0348 CABINET #23 211 702 54 88 76 160 17 0.802 12 19 4 4 8.70E-09 85.0%B_0349 CABINET #24 211 702 54 88 76 160 17 0.802 12 15 4 4 8.70E-09 85.0%B_0350 CABINET #25 211 702 54 88 76 160 17 0.802 12 13 4 4 8.70E-09 85.0%B_0352 CABINET #1 211 702 54 88 76 160 17 0.802 17 26 2 2 8.16E-09 83.7%B_0353 CABINET #2 211 702 54 88 76 160 17 0.802 18 22 2 2 8.16E-09 83.7%B_0354 CABINET #3 211 702 54 88 76 160 17 0.802 14 21 2 2 8.13E-09 84.0%B_0356 CABINET #4 211 702 54 88 76 160 17 0.802 10 15 2 2 8.24E-09 82.8%B_0357 CABINET #5 211 702 54 88 76 160 17 0.802 9 12 2 2 8.24E-09 82.8%B_0358 CABINET #6 211 702 54 88 76 160 17 0.802 10 14 2 2 8.81E-09 77.5%B_0359 CABINET #7 211 702 54 88 76 160 17 0.802 12 19 2 2 8.24E-09 82.8%B_0360 CABINET #8 211 702 54 88 76 160 17 0.802 15 18 2 2 8.62E-09 79.2%B_0361 CABINET #9 211 702 54 88 76 160 17 0.802 15 17 2 2 8.24E-09 82.8%B_0362 CABINET #10 211 702 54 88 76 160 17 0.802 16 17 2 2 6.96E-09 98.2%B_0363 CABINET #11 211 702 54 88 76 160 17 0.802 15 17 2 2 8.18E-09 83.5%B_0364 CABINET #12 211 702 54 88 76 160 17 0.802 14 15 2 2 8.16E-09 83.7%C_0183 BATTERY CHARGER – A 69 211 34 56 54 88 19 0.620 10 11 4 4 3.48E-07 79.7%C_0184 BATTERY CHARGER – A-1 69 211 34 56 54 88 19 0.620 19 20 5 5 4.71E-07 83.6%C_0185 MCC-A 69 211 34 56 54 88 N/A 0.000 3 3 0 0 1.18E-07 0.0%C_0186 MCC-B 69 211 34 56 54 88 N/A 0.000 4 4 1 1 1.99E-08 0.0%C_0188 BATTERY CHARGER – B-1 69 211 34 56 54 88 16 0.660 7 7 2 2 3.08E-09 0.0%C_0189 BATTERY CHARGER – B 69 211 34 56 54 88 42 0.322 0 3 0 1 3.11E-10 0.0%

% HGL Source ID Description SF CDF

6850 HRR 98th ZOI (in) 75th ZOI (in) 98th 

# Targets

75th 

# Targets

98th 

# Trays

75th 

# Trays

____________________________________________________________________________ 

EXAMPLES OF ENCLOSURE FIRE ANALYSIS

F-18
EXAMPLES OF ENCLOSURE FIRE ANALYSIS 

F-19 

1 F.2.3.3 Case 3 

2 For Case 3 revised HRRs were applied using the guidance described in RACHELLE_FIRE 

3 Table 4-1 and Table 4-2 as described below: 

4 

 Group 2: MCCs and Battery Chargers; 75th is 25 kW, 98th 5 is 130 kW 

 Group 4a(a): Large Enclosures, Closed; 75th is 50 kW, 98th 6 is 400 kW 

 Group 4b(a): Medium Enclosures, Closed; 75th is 25 kW, 98th 7 is 200 kW 

8 Other scenario parameters are consistent with Case 2. Table F-5 provides the updated data 

9 and results.
Table F-5 1 

Cabinet List with RACHELLE_FIRE HRRs (Case 3) 2 

3 

Binning Group To First Target

Table 4.1 and 4.2 75th 98th Horizontal Vertical Horizontal Vertical inches

A_0312 CABINET #312 4a(a), Closed, TP 50 400 30 49 69 113 44 0.189 3 3 0 0 0.00E+00 0.0%A_0314 DC HOLD CABINET 4a(a), Closed, TP 50 400 30 49 69 113 41 0.202 3 16 0 4 4.83E‐08 98.7%

A_0315 LOGIC CABINET 4a(a), Closed, TP 50 400 30 49 69 113 41 0.202 3 20 0 5 8.45E‐08 97.7%

A_0316 POWER CABINET – 2BD 4a(a), Closed, TP 50 400 30 49 69 113 46 0.180 1 5 0 0 0.00E+00 0.0%

A_0317 POWER CABINET – 2AC 4a(a), Closed, TP 50 400 30 49 69 113 41 0.202 1 26 0 7 4.46E‐07 27.1%

A_0318 POWER CABINET – 1BD 4a(a), Closed, TP 50 400 30 49 69 113 42 0.197 3 10 0 0 1.29E‐09 0.0%

A_0319 POWER CABINET – 1AC 4a(a), Closed, TP 50 400 30 49 69 113 40 0.206 5 32 0 7 2.37E‐07 25.5%

A_0320 CORE EXIT THERMOCOUPLE CABINET 4b(a), Closed, TP 25 200 22 37 53 86 N/A 0.000 4 4 0 0 0.00E+00 0.0%

A_0321 IMPACT MONITORING SYSTEM CABINET 4b(a), Closed, TP 25 200 22 37 53 86 19 0.281 3 3 0 0 0.00E+00 0.0%

B_0337 CABINET #14 4b(a), Closed, TP 25 200 22 37 53 86 17 0.296 16 23 4 4 3.84E‐09 65.7%B_0338 CABINET #15 4b(a), Closed, TP 25 200 22 37 53 86 17 0.296 11 22 4 4 3.84E‐09 65.7%B_0339 CABINET #16 4b(a), Closed, TP 25 200 22 37 53 86 17 0.296 12 23 4 4 3.82E‐09 66.2%B_0340 CABINET #17 4b(a), Closed, TP 25 200 22 37 53 86 17 0.296 16 19 4 4 3.82E‐09 66.2%B_0341 CABINET #18 4b(a), Closed, TP 25 200 22 37 53 86 17 0.296 15 20 4 4 3.82E‐09 66.2%B_0343 CABINET #19 4b(a), Closed, TP 25 200 22 37 53 86 17 0.296 12 17 4 4 3.82E‐09 66.2%B_0344 CABINET #20 4b(a), Closed, TP 25 200 22 37 53 86 17 0.296 11 14 4 4 4.23E‐09 59.8%B_0345 CABINET #21 4b(a), Closed, TP 25 200 22 37 53 86 17 0.296 9 12 4 4 2.53E‐09 99.8%B_0346 CABINET #22 4b(a), Closed, TP 25 200 22 37 53 86 17 0.296 8 9 4 4 2.53E‐09 99.8%B_0347 CABINET #28 4b(a), Closed, TP 25 200 22 37 53 86 17 0.296 8 12 4 4 2.53E‐09 99.8%

B_0348 CABINET #23 4b(a), Closed, TP 25 200 22 37 53 86 17 0.296 11 12 4 4 3.82E‐09 66.2%B_0349 CABINET #24 4b(a), Closed, TP 25 200 22 37 53 86 17 0.296 11 12 4 4 3.82E‐09 66.2%B_0350 CABINET #25 4b(a), Closed, TP 25 200 22 37 53 86 17 0.296 7 12 3 4 3.82E‐09 66.2%B_0352 CABINET #1 4b(a), Closed, TP 25 200 22 37 53 86 17 0.296 6 17 2 2 2.16E‐09 39.1%B_0353 CABINET #2 4b(a), Closed, TP 25 200 22 37 53 86 17 0.296 8 13 2 2 2.16E‐09 39.0%B_0354 CABINET #3 4b(a), Closed, TP 25 200 22 37 53 86 17 0.296 4 12 2 2 2.13E‐09 39.6%

B_0356 CABINET #4 4b(a), Closed, TP 25 200 22 37 53 86 17 0.296 6 8 2 2 2.13E‐09 39.6%B_0357 CABINET #5 4b(a), Closed, TP 25 200 22 37 53 86 17 0.296 4 8 2 2 2.15E‐09 39.3%B_0358 CABINET #6 4b(a), Closed, TP 25 200 22 37 53 86 17 0.296 4 10 2 2 2.31E‐09 36.6%B_0359 CABINET #7 4b(a), Closed, TP 25 200 22 37 53 86 17 0.296 5 9 2 2 2.16E‐09 39.0%B_0360 CABINET #8 4b(a), Closed, TP 25 200 22 37 53 86 17 0.296 6 11 2 2 2.55E‐09 33.2%

B_0361 CABINET #9 4b(a), Closed, TP 25 200 22 37 53 86 17 0.296 4 14 2 2 2.15E‐09 39.3%B_0362 CABINET #10 4b(a), Closed, TP 25 200 22 37 53 86 17 0.296 9 16 2 2 8.62E‐10 98.0%B_0363 CABINET #11 4b(a), Closed, TP 25 200 22 37 53 86 17 0.296 9 14 2 2 2.16E‐09 39.0%B_0364 CABINET #12 4b(a), Closed, TP 25 200 22 37 53 86 17 0.296 5 14 2 2 2.16E‐09 39.0%C_0183 BATTERY CHARGER – A 2, TP 25 130 22 37 44 72 19 0.340 5 10 2 4 8.74E‐08 56.2%C_0184 BATTERY CHARGER – A‐1 2, TP 25 130 22 37 44 72 19 0.340 19 19 5 5 2.43E‐07 82.7%

C_0185 MCC‐A 2, TP 25 130 22 37 44 72 N/A 0.000 0 0 0 0 1.18E‐07 0.0%C_0186 MCC‐B 2, TP 25 130 22 37 44 72 N/A 0.000 0 0 0 0 1.99E‐08 0.0%

C_0188 BATTERY CHARGER – B‐1 2, TP 25 130 22 37 44 72 16 0.374 7 7 2 2 1.76E‐09 0.0%

C_0189 BATTERY CHARGER – B 2, TP 25 130 22 37 44 72 42 0.140 0 1 0 0 0.00E+00 0.0%

Source ID Description

HRR 98th ZOI (in) SF 75th ZOI (in) 75th # Targets 98th # Trays 75th # Trays % HGL CDF 98th # Targets

____________________________________________________________________________ 

EXAMPLES OF ENCLOSURE FIRE ANALYSIS

F-20
EXAMPLES OF ENCLOSURE FIRE ANALYSIS 

F-21 

1 F.2.3.4 Case 4 

2 

3 In addition to updated HRRs, Case 4 accounts for the obstructed plume due to the cabinet 

4 enclosure. Based on the guidance presented in this report, the plume temperature will exhibit a 

5 38% temperature reduction (Chapter 6) resulting in a vertical ZOI reduction of 24% (Chapter 6). 

6 These reductions were applied and the CDFs calculated using the same process as for cases 1 

7 and 2. The results are presented in Table F-6. 

8 
Table F-6 1 

Cabinet List with RACHELLE_FIRE HRRs and Obstructed Plume (Case 4) 2 

3 

4 

Binning Group To First Target

Table 4.1 and 4.2 75th 98th Horizontal Vertical Horizontal Vertical inches

A_0312 CABINET #312 4a(a), Closed, TP 50 400 30 37 69 84 44 0.118 0 3 0 0 0.00E+00 0.0%A_0314 DC HOLD CABINET 4a(a), Closed, TP 50 400 30 37 69 84 41 0.129 0 16 0 4 4.83E‐08 98.7%

A_0315 LOGIC CABINET 4a(a), Closed, TP 50 400 30 37 69 84 41 0.129 0 20 0 5 8.45E‐08 97.7%

A_0316 POWER CABINET – 2BD 4a(a), Closed, TP 50 400 30 37 69 84 46 0.110 0 5 0 0 0.00E+00 0.0%

A_0317 POWER CABINET – 2AC 4a(a), Closed, TP 50 400 30 37 69 84 41 0.129 0 26 0 7 4.46E‐07 27.1%

A_0318 POWER CABINET – 1BD 4a(a), Closed, TP 50 400 30 37 69 84 42 0.125 0 10 0 0 1.29E‐09 0.0%

A_0319 POWER CABINET – 1AC 4a(a), Closed, TP 50 400 30 37 69 84 40 0.133 0 32 0 7 2.37E‐07 25.5%

A_0320 CORE EXIT THERMOCOUPLE CABINET 4b(a), Closed, TP 25 200 22 28 53 64 N/A 0.000 4 4 0 0 0.00E+00 0.0%

A_0321 IMPACT MONITORING SYSTEM CABINET 4b(a), Closed, TP 25 200 22 28 53 64 19 0.204 3 3 0 0 0.00E+00 0.0%

B_0337 CABINET #14 4b(a), Closed, TP 25 200 22 28 53 64 17 0.219 17 23 4 4 3.19E‐09 58.7%B_0338 CABINET #15 4b(a), Closed, TP 25 200 22 28 53 64 17 0.219 12 22 4 4 3.19E‐09 58.7%B_0339 CABINET #16 4b(a), Closed, TP 25 200 22 28 53 64 17 0.219 13 23 4 4 3.16E‐09 59.2%B_0340 CABINET #17 4b(a), Closed, TP 25 200 22 28 53 64 17 0.219 17 19 4 4 3.16E‐09 59.3%B_0341 CABINET #18 4b(a), Closed, TP 25 200 22 28 53 64 17 0.219 16 20 4 4 3.16E‐09 59.3%B_0343 CABINET #19 4b(a), Closed, TP 25 200 22 28 53 64 17 0.219 12 17 4 4 3.16E‐09 59.3%B_0344 CABINET #20 4b(a), Closed, TP 25 200 22 28 53 64 17 0.219 11 14 4 4 3.57E‐09 52.5%B_0345 CABINET #21 4b(a), Closed, TP 25 200 22 28 53 64 17 0.219 9 12 4 4 1.88E‐09 99.8%B_0346 CABINET #22 4b(a), Closed, TP 25 200 22 28 53 64 17 0.219 8 9 4 4 1.88E‐09 99.8%B_0347 CABINET #28 4b(a), Closed, TP 25 200 22 28 53 64 17 0.219 8 12 4 4 1.88E‐09 99.8%

B_0348 CABINET #23 4b(a), Closed, TP 25 200 22 28 53 64 17 0.219 11 12 4 4 3.16E‐09 59.3%B_0349 CABINET #24 4b(a), Closed, TP 25 200 22 28 53 64 17 0.219 11 12 4 4 3.16E‐09 59.3%

B_0350 CABINET #25 4b(a), Closed, TP 25 200 22 28 53 64 17 0.219 7 12 3 4 3.16E‐09 59.3%

B_0352 CABINET #1 4b(a), Closed, TP 25 200 22 28 53 64 17 0.219 6 17 2 2 2.16E‐09 39.1%

B_0353 CABINET #2 4b(a), Closed, TP 25 200 22 28 53 64 17 0.219 8 13 2 2 2.16E‐09 39.0%

B_0354 CABINET #3 4b(a), Closed, TP 25 200 22 28 53 64 17 0.219 4 12 2 2 2.13E‐09 39.6%

B_0356 CABINET #4 4b(a), Closed, TP 25 200 22 28 53 64 17 0.219 6 8 2 2 2.13E‐09 39.6%

B_0357 CABINET #5 4b(a), Closed, TP 25 200 22 28 53 64 17 0.219 4 8 2 2 2.15E‐09 39.3%B_0358 CABINET #6 4b(a), Closed, TP 25 200 22 28 53 64 17 0.219 4 10 2 2 2.28E‐09 37.1%

B_0359 CABINET #7 4b(a), Closed, TP 25 200 22 28 53 64 17 0.219 5 9 2 2 2.16E‐09 39.1%

B_0360 CABINET #8 4b(a), Closed, TP 25 200 22 28 53 64 17 0.219 6 11 2 2 2.54E‐09 33.3%

B_0361 CABINET #9 4b(a), Closed, TP 25 200 22 28 53 64 17 0.219 4 14 2 2 2.15E‐09 39.3%B_0362 CABINET #10 4b(a), Closed, TP 25 200 22 28 53 64 17 0.219 9 16 2 2 8.61E‐10 98.1%

B_0363 CABINET #11 4b(a), Closed, TP 25 200 22 28 53 64 17 0.219 9 14 2 2 2.16E‐09 39.0%

B_0364 CABINET #12 4b(a), Closed, TP 25 200 22 28 53 64 17 0.219 5 14 2 2 2.16E‐09 39.0%

C_0183 BATTERY CHARGER – A 2, TP 25 130 22 28 44 54 19 0.235 2 10 0 4 6.12E‐08 80.2%

C_0184 BATTERY CHARGER – A‐1 2, TP 25 130 22 28 44 54 19 0.235 19 19 5 5 1.74E‐07 82.9%

C_0185 MCC‐A 2, TP 25 130 22 28 44 54 N/A 0.000 0 0 0 0 1.18E‐07 0.0%

C_0186 MCC‐B 2, TP 25 130 22 28 44 54 N/A 0.000 0 0 0 0 1.99E‐08 0.0%

C_0188 BATTERY CHARGER – B‐1 2, TP 25 130 22 28 44 54 16 0.270 7 7 2 2 1.29E‐09 0.0%

C_0189 BATTERY CHARGER – B 2, TP 25 130 22 28 44 54 42 0.063 0 1 0 0 0.00E+00 0.0%

Source ID Description

HRR 98th ZOI (in) SF % HGL CDF 75th ZOI (in) 98th # Targets 75th # Targets 98th # Trays 75th # Trays

____________________________________________________________________________ 

EXAMPLES OF ENCLOSURE FIRE ANALYSIS

F-22
EXAMPLES OF ENCLOSURE FIRE ANALYSIS 

F-23 

1 F.2.3.5 Case 5 

2 

3 For cabinets contributing significantly to risk, additional internal inspections were made to 

4 evaluate the fuel loading level, fuel type, and cable bundling arrangement to see if further 

5 reduction to the cabinet’s HRR was possible. The following photos show cabinets for which the 

6 HRR could be further reduced. 

7 Fire Compartment A 

8 Source 0315 

9 

10 Figure F-7 

11 Photos of Source 0315 Outside (right cabinet in photo) and Inside 

12 The fuel load for Source 0315 (Figure F-7) is a single cable bundle that is tightly bound and 

13 does not hang loosely. However the circuit cards present are in moderate quantities. 

14 

15 Based on the guidance provided in Table 4-1, re-binning the cabinet from Default (Table 4-2, 

16 Group 4a(a)) to Low (Table 4-2, Group 4a(b)) is not justified. The amount of circuit cards 

17 precludes re-grouping to a lower combustible load. 

18 
EXAMPLES OF ENCLOSURE FIRE ANALYSIS 

F-24 

1 Source 0319 

2 

3 Figure F-8 

4 Photos of Source 0319 Outside and Inside 

5 Sources 0317 and 0319 (Figure F-8) are both power cabinets with similar combustible loading. 

6 The fuel load is at most moderate and the cable bundle arrangement is comprised of tightly 

7 bundled cables and arranged in an orderly manner. There are only a handful of exposed 

8 printed circuit cards present. 

9 

10 Based on the guidance provided in Table 4-1, re-binning the cabinet from Default (Table 4-2, 

11 Group 4a(a)) to Low (Table 4-2, Group 4a(b)) is acceptable. 

12 

13 

14 
EXAMPLES OF ENCLOSURE FIRE ANALYSIS 

F-25 

1 Fire Compartment B 

2 Source 0362 

3 

4 Figure F-9 

5 Photo of Source 0362 Outside 

6 

7 

8 

9 Figure F-10 

10 Photo of Source 0362 Inside Front 
EXAMPLES OF ENCLOSURE FIRE ANALYSIS 

F-26 

1 2 

3 Figure F-11 

4 Photos of Source 0362 Inside Rear 

5 Source 0362 (Figures F-9, F-10, and F-11) is indicative of all other power cabinets within this 

6 compartment. The fuel load is at most moderate, with very few cables. Most of the cabinet is 

7 comprised of non-combustible material. 

8 

9 Based on the guidance provided in Table 4-1, re-binning the cabinet from Default (Table 4-2, 

10 Group 4b(a)) to Low (Table 4-2, Group 4b(b)) is acceptable. HRRs were applied as follows: 

11 

 Group 2: Battery Chargers; 75th is 25 kW, 98th 12 is 130 kW 

 Group 4a(a): Large Enclosures, Closed; 75th is 50 kW, 98th 13 is 400 kW 

 Group 4a(b): Large Enclosures, Closed; 75th is 25 kW, 98th 14 is 200 kW 

 Group 4b(a): Medium Enclosures, Closed; 75th is 25 kW, 98th 15 is 200 kW 

 Group 4b(b): Medium Enclosures, Closed; 75th is 15 kW, 98th 16 is 100 kW 

17 

18 
Table F-7 1 

Credit for Inspecting Cabinet Internals (Case 5) 2 

3 

Binning Group To First Target

Table 4.1 and 4.2 75th 98th Horizontal Vertical Horizontal Vertical inches

A_0312 CABINET #312 4a(a), Closed, TP 50 400 30 37 69 84 44 0.118 0 3 0 0 0.00E+00 0.0%A_0314 DC HOLD CABINET 4a(a), Closed, TP 50 400 30 37 69 84 41 0.129 0 16 0 4 4.83E‐08 98.7%

A_0315 LOGIC CABINET 4a(a), Closed, TP 50 400 30 37 69 84 41 0.129 0 20 0 5 8.45E‐08 97.7%

A_0316 POWER CABINET – 2BD 4a(a), Closed, TP 50 400 30 37 69 84 46 0.110 0 5 0 0 0.00E+00 0.0%

A_0317 POWER CABINET – 2AC 4a(b), Closed, TP 25 200 22 28 53 64 41 0.084 0 14 0 4 2.08E‐08 99.7%

A_0318 POWER CABINET – 1BD 4a(a), Closed, TP 50 400 30 37 69 84 42 0.125 0 10 0 0 1.29E‐09 0.0%

A_0319 POWER CABINET – 1AC 4a(b), Closed, TP 25 200 22 28 53 64 40 0.087 0 16 0 2 1.31E‐10 0.0%

A_0320 CORE EXIT THERMOCOUPLE CABINET 4b(a), Closed, TP 25 200 22 28 53 64 N/A 0.000 4 4 0 0 0.00E+00 0.0%

A_0321 IMPACT MONITORING SYSTEM CABINET 4b(a), Closed, TP 25 200 22 28 53 64 19 0.204 3 3 0 0 0.00E+00 0.0%

B_0337 CABINET #14 4b(b), Closed, TP 15 100 18 23 40 48 17 0.199 16 21 4 4 3.00E‐09 56.1%B_0338 CABINET #15 4b(b), Closed, TP 15 100 18 23 40 48 17 0.199 11 20 4 4 3.00E‐09 56.1%B_0339 CABINET #16 4b(b), Closed, TP 15 100 18 23 40 48 17 0.199 12 20 4 4 2.98E‐09 56.7%B_0340 CABINET #17 4b(b), Closed, TP 15 100 18 23 40 48 17 0.199 16 18 4 4 2.97E‐09 56.7%B_0341 CABINET #18 4b(b), Closed, TP 15 100 18 23 40 48 17 0.199 14 19 4 4 2.97E‐09 56.7%B_0343 CABINET #19 4b(b), Closed, TP 15 100 18 23 40 48 17 0.199 12 13 4 4 2.97E‐09 56.7%B_0344 CABINET #20 4b(b), Closed, TP 15 100 18 23 40 48 17 0.199 11 14 4 4 3.38E‐09 49.9%B_0345 CABINET #21 4b(b), Closed, TP 15 100 18 23 40 48 17 0.199 9 11 4 4 1.69E‐09 99.8%B_0346 CABINET #22 4b(b), Closed, TP 15 100 18 23 40 48 17 0.199 8 9 4 4 1.69E‐09 99.8%B_0347 CABINET #28 4b(b), Closed, TP 15 100 18 23 40 48 17 0.199 8 11 4 4 1.69E‐09 99.8%

B_0348 CABINET #23 4b(b), Closed, TP 15 100 18 23 40 48 17 0.199 11 11 4 4 2.97E‐09 56.7%B_0349 CABINET #24 4b(b), Closed, TP 15 100 18 23 40 48 17 0.199 11 12 4 4 2.97E‐09 56.7%B_0350 CABINET #25 4b(b), Closed, TP 15 100 18 23 40 48 17 0.199 7 12 3 4 2.97E‐09 56.7%B_0352 CABINET #1 4b(b), Closed, TP 15 100 18 23 40 48 17 0.199 5 16 2 2 1.32E‐09 0.0%B_0353 CABINET #2 4b(b), Closed, TP 15 100 18 23 40 48 17 0.199 7 12 2 2 1.32E‐09 0.0%B_0354 CABINET #3 4b(b), Closed, TP 15 100 18 23 40 48 17 0.199 4 11 2 2 1.29E‐09 0.0%

B_0356 CABINET #4 4b(b), Closed, TP 15 100 18 23 40 48 17 0.199 6 7 2 2 1.29E‐09 0.0%B_0357 CABINET #5 4b(b), Closed, TP 15 100 18 23 40 48 17 0.199 4 7 2 2 1.29E‐09 0.0%B_0358 CABINET #6 4b(b), Closed, TP 15 100 18 23 40 48 17 0.199 4 6 2 2 1.41E‐09 0.0%B_0359 CABINET #7 4b(b), Closed, TP 15 100 18 23 40 48 17 0.199 4 7 2 2 1.30E‐09 0.0%B_0360 CABINET #8 4b(b), Closed, TP 15 100 18 23 40 48 17 0.199 5 10 2 2 1.69E‐09 0.0%

B_0361 CABINET #9 4b(b), Closed, TP 15 100 18 23 40 48 17 0.199 4 14 2 2 1.30E‐09 0.0%B_0362 CABINET #10 4b(b), Closed, TP 15 100 18 23 40 48 17 0.199 9 13 2 2 2.76E‐12 0.0%B_0363 CABINET #11 4b(b), Closed, TP 15 100 18 23 40 48 17 0.199 8 13 2 2 1.32E‐09 0.0%B_0364 CABINET #12 4b(b), Closed, TP 15 100 18 23 40 48 17 0.199 5 13 2 2 1.32E‐09 0.0%C_0183 BATTERY CHARGER – A 2, TP 25 130 22 28 44 54 19 0.235 2 10 0 4 6.12E‐08 80.2%C_0184 BATTERY CHARGER – A‐1 2, TP 25 130 22 28 44 54 19 0.235 19 19 5 5 1.74E‐07 82.9%

C_0185 MCC‐A 2, TP 25 130 22 28 44 54 N/A 0.000 0 0 0 0 1.18E‐07 0.0%C_0186 MCC‐B 2, TP 25 130 22 28 44 54 N/A 0.000 0 0 0 0 1.99E‐08 0.0%

C_0188 BATTERY CHARGER – B‐1 2, TP 25 130 22 28 44 54 16 0.270 7 7 2 2 1.29E‐09 0.0%

C_0189 BATTERY CHARGER – B 2, TP 25 130 22 28 44 54 42 0.063 0 1 0 0 0.00E+00 0.0%

Source ID Description

HRR 98th ZOI (in) SF % HGL CDF 75th ZOI (in) 98th # Targets 75th # Targets 98th # Trays 75th # Trays

____________________________________________________________________________ 

EXAMPLES OF ENCLOSURE FIRE ANALYSIS

F-27
EXAMPLES OF ENCLOSURE FIRE ANALYSIS 

F-28 

1 F.2.3.6 Additional Case 2a 

2 

3 In many plants modifications are required to reduce risk. In this example, Case 2 represents an 

4 analysis that has applied a significant amount of fire modeling refinement; however, the risk may 

5 still be higher than required to meet the application. Because a high percentage of the risk is 

6 due to HGL development, the addition of an automatic suppression system may be an option. 

7 

8 Case 2a was added to compare the benefits of applying the RACHELLE_FIRE guidance 

9 compared to installing a modification to provide automatic suppression. The automatic 

10 suppression is assumed to be 95% effective at preventing fire spread beyond the local damage 

11 set (i.e., preventing HGL). The results for Case 2a are presented in Table F-8. Note that 

12 manual suppression is included in both Case 2 and 2a and also has some impact on HGL 

13 development. 

14 

15 
EXAMPLES OF ENCLOSURE FIRE ANALYSIS 

F-29 

1 Table F-8 

2 Case 2 with Automatic Suppression Credit (Case 2a) 

3 

A_0312 CABINET #312 0.00E+00 0.0%

A_0314 DC HOLD CABINET 4.26E‐08 86.6%

A_0315 LOGIC CABINET 5.29E‐08 83.8%

A_0316 POWER CABINET – 2BD 0.00E+00 0.0%

A_0317 POWER CABINET – 2AC 1.49E‐06 3.5%

A_0318 POWER CABINET – 1BD 4.87E‐09 0.0%

A_0319 POWER CABINET – 1AC 8.19E‐07 2.9%

A_0320 CORE EXIT THERMOCOUPLE CABINET 0.00E+00 0.0%

A_0321 IMPACT MONITORING SYSTEM CABINET 0.00E+00 0.0%

B_0337 CABINET #14 6.61E‐08 8.7%

B_0338 CABINET #15 6.61E‐08 8.7%

B_0339 CABINET #16 1.25E‐08 46.0%

B_0340 CABINET #17 7.04E‐09 81.5%

B_0341 CABINET #18 7.04E‐09 81.5%

B_0343 CABINET #19 7.05E‐09 81.3%

B_0344 CABINET #20 7.53E‐09 76.2%

B_0345 CABINET #21 5.77E‐09 99.4%

B_0346 CABINET #22 5.75E‐09 99.7%

B_0347 CABINET #28 5.75E‐09 99.7%

B_0348 CABINET #23 7.04E‐09 81.5%

B_0349 CABINET #24 7.04E‐09 81.5%

B_0350 CABINET #25 7.04E‐09 81.5%

B_0352 CABINET #1 7.04E‐09 81.1%

B_0353 CABINET #2 7.04E‐09 81.1%

B_0354 CABINET #3 7.01E‐09 81.4%

B_0356 CABINET #4 7.12E‐09 80.1%

B_0357 CABINET #5 7.12E‐09 80.1%

B_0358 CABINET #6 7.69E‐09 74.2%

B_0359 CABINET #7 7.12E‐09 80.1%

B_0360 CABINET #8 7.50E‐09 76.1%

B_0361 CABINET #9 7.12E‐09 80.1%

B_0362 CABINET #10 5.83E‐09 97.8%

B_0363 CABINET #11 7.05E‐09 80.9%

B_0364 CABINET #12 7.04E‐09 81.1%

C_0183 BATTERY CHARGER – A 1.17E‐07 35.1%

C_0184 BATTERY CHARGER – A‐1 1.32E‐07 35.4%

C_0185 MCC‐A 1.18E‐07 0.0%

C_0186 MCC‐B 1.99E‐08 0.0%

C_0188 BATTERY CHARGER – B‐1 3.08E‐09 0.0%

C_0189 BATTERY CHARGER – B 3.11E‐10 0.0%

Source ID Description CDF % HGL
EXAMPLES OF ENCLOSURE FIRE ANALYSIS 

F-30 

1 F.2.4 Results Review 

2 Table F-9 provides a summary of the CDF results by compartment for each of the cases 

3 evaluated. The CDFs for Case 1 indicate relatively high risk numbers prior to applying more 

4 refined fire modeling. Before evaluating the RACHELLE_FIRE HRRs it is desired to apply 

5 currently available guidance as described in Appendix F.2.3.2 in order to get a realistic measure 

6 of the potential CDF impacts using the revised guidance. From Table F-10 it can be seen that 

7 there was about 64% reduction in CDF due to the refinements applied. These results are used 

8 as the baseline to evaluate the RACHELLE_FIRE impacts. 

9 

10 

11 Table F-9 

12 Compartment CDF Comparison 

Compartment Case 1 Case 2 Case 3 Case 4 Case 5

A 8.18E‐06 3.13E‐06 8.18E‐07 8.18E‐07 1.55E‐07

B 2.27E‐06 3.31E‐07 7.13E‐08 6.28E‐08 5.02E‐08

C 2.10E‐06 9.61E‐07 4.69E‐07 3.74E‐07 4.01E‐07

all 1.26E‐05 4.42E‐06 1.36E‐06 1.25E‐06 6.06E‐07

13 

14 

15 Table F-10 

16 CDF Reduction Percentages Between Cases 

Compartment Case

1to2

Case

2to3

Case

3to4

Case

4to5

Case

2to4

Case

2to5

A 61.8% 73.8% 0.0% 81.0% 73.8% 95.0%

B 85.4% 78.4% 12.0% 20.2% 81.0% 84.8%

C 54.3% 51.1% 20.4% 0.0% 61.1% 61.1%

all 64.8% 69.3% 7.7% 53.8% 71.6% 86.9%

17 

18 

19 Applying the revised guidance presented in RACHELLE_FIRE resulted in an overall calculated 

20 CDF reduction of nearly 87% for the locations evaluated. However, the benefits varied based on 

21 the room configurations. Tables F-11 through F-14 provide a comparison of specific 

22 parameters, and results for the various cases. 

23 

24 The most obvious contribution to the CDF reduction is due to the reduction of the severity 

25 factors (Table F-13). Overall severity factors were reduced by about 74% on average. This 

26 reduction represents the fraction of the HRR distribution that can cause damage to targets. 

27 Figure F-12 provides a comparison of the possible change in severity factors based on MCC 

28 HRRs between NUREG/CR-6850 guidance and RACHELLE_FIRE guidance assuming qualified 

29 cables, thermoplastic targets, and other parameters used for this example. 

30 
EXAMPLES OF ENCLOSURE FIRE ANALYSIS 

F-31 

1 

2 

3 Figure F-12 

4 Severity Factor Comparison 

5 

6 The CDF is also reduced based on a smaller ZOI for the RACHELLE_FIRE HRRs. The smaller 

7 ZOIs allow some targets to be excluded from the analysis. The total number of targets was 

reduced by 36% for the 98th percentile fires, and 54% for the 75th 8 percentile fires (Ref. Table 

9 F-12). The largest impact was due to the reduction in horizontal ZOI because most of these 

10 targets were not involved in fire propagation. The vertical ZOI showed less impact due to the 

11 propagation of secondary combustibles (i.e., cable trays). It follows that there can still be a 

12 significant potential to develop HGL even with the updated HRRs applied. This is mainly a 

13 function of the amount of secondary combustibles and nearness to the ignition source. In some 

14 scenarios, the percentage of CDF due to HGL increased because the number of targets in the 

15 local target set was reduced but the probability of developing HGL did not change if the nearest 

16 cable tray was still within the ZOI. 

17 

18 The impacts vary by compartment based on the source target configurations and the room 

19 parameters. Compartment A had the greatest CDF reduction at 95%. Compartment A is an 

20 average room with most targets at least 24 inches from the source. Compartment B also had a 

21 significant CDF reduction of about 84%. A substantial benefit was realized in these 

22 compartments based on the HRR refinements in Case 5. Compartment C had less impact but 

23 still saw a 61% reduction in CDF by applying the guidance. The impacts from treatment of 

0.000

0.100

0.200

0.300

0.400

0.500

0.600

0.700

0.800

0.900

1.000

0 10 20 30 40 50 60 70 80 90 100 110 120 130 140

Severity Factor

Target Distance (inches)

NUREG/CR-6850

RACHELLE_FIRE
EXAMPLES OF ENCLOSURE FIRE ANALYSIS 

F-32 

1 obstructed plumes varied from less than 1% up to 20% reduction in CDF for compartments A 

2 and C respectively. 

3 

4 A comparison was also made based on adding suppression versus applying the 

5 RACHELLE_FIRE guidance. The results presented in Table F-11 show that the CDF reduction 

6 of the modification was not as much as from applying the RACHELLE_FIRE guidance. 

7 

8 

9 Table F-11 

10 Modification Impact Comparison 

Compartment

Case 2

(no supp)

Case 2a

(w/supp)

Case 5

(no supp)

Case

2to2a

Case  

2to5

A 3.13E‐06 2.41E‐06 1.55E‐07 23.0% 95.0%

B 3.31E‐07 2.96E‐07 5.02E‐08 10.4% 84.8%

C 9.61E‐07 3.90E‐07 4.01E‐07 59.4% 61.1%

all 4.42E‐06 3.10E‐06 6.06E‐07 29.9% 86.9%

11 

12 
EXAMPLES OF ENCLOSURE FIRE ANALYSIS 

F-33 

1 Table F-12 

2 Comparison of Number of Targets 

3 

4 

5 

6 

Case 1 Case 2 Case 3 Case 4 Case 5 Case 1 Case 2 Case 3 Case 4 Case 5

A_0312 3 3 3 3 3 N/A 3 3 0 0

A_0314 20 20 16 16 16 N/A 13 3 0 0

A_0315 20 20 20 20 20 N/A 20 3 0 0

A_0316 5 5 5 5 5 N/A 4 1 0 0

A_0317 30 30 26 26 14 N/A 25 1 0 0

A_0318 10 10 10 10 10 N/A 10 3 0 0

A_0319 34 34 32 32 16 N/A 25 5 0 0

A_0320 4 4 4 4 4 N/A 4 4 4 4

A_0321 3 3 3 3 3 N/A 3 3 3 3

B_0337 37 37 23 23 21 N/A 24 16 17 16

B_0338 34 34 22 22 20 N/A 29 11 12 11

B_0339 33 33 23 23 20 N/A 26 12 13 12

B_0340 29 29 19 19 18 N/A 23 16 17 16

B_0341 25 25 20 20 19 N/A 20 15 16 14

B_0343 24 24 17 17 13 N/A 18 12 12 12

B_0344 22 22 14 14 14 N/A 14 11 11 11

B_0345 21 21 12 12 11 N/A 13 9 9 9

B_0346 21 21 9 9 9 N/A 14 8 8 8

B_0347 19 19 12 12 11 N/A 12 8 8 8

B_0348 19 19 12 12 11 N/A 12 11 11 11

B_0349 15 15 12 12 12 N/A 12 11 11 11

B_0350 13 13 12 12 12 N/A 12 7 7 7

B_0352 26 26 17 17 16 N/A 17 6 6 5

B_0353 22 22 13 13 12 N/A 18 8 8 7

B_0354 21 21 12 12 11 N/A 14 4 4 4

B_0356 15 15 8 8 7 N/A 10 6 6 6

B_0357 12 12 8 8 7 N/A 9 4 4 4

B_0358 14 14 10 10 6 N/A 10 4 4 4

B_0359 19 19 9 9 7 N/A 12 5 5 4

B_0360 18 18 11 11 10 N/A 15 6 6 5

B_0361 17 17 14 14 14 N/A 15 4 4 4

B_0362 17 17 16 16 13 N/A 16 9 9 9

B_0363 17 17 14 14 13 N/A 15 9 9 8

B_0364 15 15 14 14 13 N/A 14 5 5 5

C_0183 11 11 10 10 10 N/A 10 5 2 2

C_0184 20 20 19 19 19 N/A 19 19 19 19

C_0185 3 3 0 0 0 N/A 3 0 0 0

C_0186 4 4 0 0 0 N/A 4 0 0 0

C_0188 7 7 7 7 7 N/A 7 7 7 7

C_0189 3 3 1 1 1 N/A 0 0 0 0

Total 702 702 509 509 448 0 544 274 257 246

Source ID

# of Targets (98th) # of Targets (75th)
EXAMPLES OF ENCLOSURE FIRE ANALYSIS 

F-34 

1 Table F-13 

2 Severity Factor Comparison 

3 

4 

5 

Case 1 Case 2 Case 3 Case 4 Case 5

A_0312 0.648 0.299 0.189 0.118 0.118

A_0314 0.828 0.478 0.202 0.129 0.129

A_0315 0.828 0.478 0.202 0.129 0.129

A_0316 0.786 0.440 0.180 0.110 0.110

A_0317 0.828 0.478 0.202 0.129 0.084

A_0318 0.807 0.471 0.197 0.125 0.125

A_0319 0.821 0.486 0.206 0.133 0.087

A_0320 0.000 0.000 0.000 0.000 0.000

A_0321 0.917 0.620 0.281 0.204 0.204

B_0337 0.958 0.802 0.296 0.219 0.199

B_0338 0.958 0.802 0.296 0.219 0.199

B_0339 0.958 0.802 0.296 0.219 0.199

B_0340 0.958 0.802 0.296 0.219 0.199

B_0341 0.958 0.802 0.296 0.219 0.199

B_0343 0.958 0.802 0.296 0.219 0.199

B_0344 0.958 0.802 0.296 0.219 0.199

B_0345 0.958 0.802 0.296 0.219 0.199

B_0346 0.958 0.802 0.296 0.219 0.199

B_0347 0.958 0.802 0.296 0.219 0.199

B_0348 0.958 0.802 0.296 0.219 0.199

B_0349 0.958 0.802 0.296 0.219 0.199

B_0350 0.958 0.802 0.296 0.219 0.199

B_0352 0.958 0.802 0.296 0.219 0.199

B_0353 0.958 0.802 0.296 0.219 0.199

B_0354 0.958 0.802 0.296 0.219 0.199

B_0356 0.958 0.802 0.296 0.219 0.199

B_0357 0.958 0.802 0.296 0.219 0.199

B_0358 0.958 0.802 0.296 0.219 0.199

B_0359 0.958 0.802 0.296 0.219 0.199

B_0360 0.958 0.802 0.296 0.219 0.199

B_0361 0.958 0.802 0.296 0.219 0.199

B_0362 0.958 0.802 0.296 0.219 0.199

B_0363 0.958 0.802 0.296 0.219 0.199

B_0364 0.958 0.802 0.296 0.219 0.199

C_0183 0.854 0.620 0.340 0.235 0.235

C_0184 0.924 0.620 0.340 0.235 0.235

C_0185 0.000 0.000 0.000 0.000 0.000

C_0186 0.000 0.000 0.000 0.000 0.000

C_0188 0.900 0.660 0.374 0.270 0.270

C_0189 0.538 0.322 0.140 0.063 0.063

Avg. 0.841 0.651 0.256 0.184 0.169

Source ID Severity Factor
EXAMPLES OF ENCLOSURE FIRE ANALYSIS 

F-35 

1 

2 Table F-14 

3 Comparison of HGL Fraction 

4 

5 

6 

7 

Case 1 Case 2 Case 3 Case 4 Case 5 Case 1 Case 2 Case 3 Case 4 Case 5

A_0312 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.0% 0.0% 0.0% 0.0% 0.0%

A_0314 9.26E‐07 1.58E‐07 4.83E‐08 4.83E‐08 4.83E‐08 98.2% 96.5% 98.7% 98.7% 98.7%

A_0315 1.02E‐06 3.09E‐07 8.45E‐08 8.45E‐08 8.45E‐08 98.4% 97.4% 97.7% 97.7% 97.7%

A_0316 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.0% 0.0% 0.0% 0.0% 0.0%

A_0317 4.12E‐06 1.74E‐06 4.46E‐07 4.46E‐07 2.08E‐08 32.5% 25.6% 27.1% 27.1% 99.7%

A_0318 1.12E‐08 4.87E‐09 1.29E‐09 1.29E‐09 1.29E‐09 0.0% 0.0% 0.0% 0.0% 0.0%

A_0319 2.10E‐06 9.11E‐07 2.37E‐07 2.37E‐07 1.31E‐10 31.7% 19.0% 25.5% 25.5% 0.0%

A_0320 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.0% 0.0% 0.0% 0.0% 0.0%

A_0321 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.0% 0.0% 0.0% 0.0% 0.0%

B_0337 7.93E‐07 6.74E‐08 3.84E‐09 3.19E‐09 3.00E‐09 4.3% 11.0% 65.7% 58.7% 56.1%

B_0338 7.93E‐07 6.74E‐08 3.84E‐09 3.19E‐09 3.00E‐09 4.3% 11.0% 65.7% 58.7% 56.1%

B_0339 1.05E‐07 1.41E‐08 3.82E‐09 3.16E‐09 2.98E‐09 32.4% 52.5% 66.2% 59.2% 56.7%

B_0340 3.53E‐08 8.70E‐09 3.82E‐09 3.16E‐09 2.97E‐09 96.3% 85.0% 66.2% 59.3% 56.7%

B_0341 3.53E‐08 8.70E‐09 3.82E‐09 3.16E‐09 2.97E‐09 96.3% 85.0% 66.2% 59.3% 56.7%

B_0343 3.55E‐08 8.72E‐09 3.82E‐09 3.16E‐09 2.97E‐09 95.7% 84.9% 66.2% 59.3% 56.7%

B_0344 3.59E‐08 9.19E‐09 4.23E‐09 3.57E‐09 3.38E‐09 94.7% 80.5% 59.8% 52.5% 49.9%

B_0345 3.43E‐08 7.43E‐09 2.53E‐09 1.88E‐09 1.69E‐09 99.3% 99.6% 99.8% 99.8% 99.8%

B_0346 3.40E‐08 7.41E‐09 2.53E‐09 1.88E‐09 1.69E‐09 99.9% 99.8% 99.8% 99.8% 99.8%

B_0347 3.40E‐08 7.41E‐09 2.53E‐09 1.88E‐09 1.69E‐09 99.9% 99.8% 99.8% 99.8% 99.8%

B_0348 3.53E‐08 8.70E‐09 3.82E‐09 3.16E‐09 2.97E‐09 96.3% 85.0% 66.2% 59.3% 56.7%

B_0349 3.53E‐08 8.70E‐09 3.82E‐09 3.16E‐09 2.97E‐09 96.3% 85.0% 66.2% 59.3% 56.7%

B_0350 3.53E‐08 8.70E‐09 3.82E‐09 3.16E‐09 2.97E‐09 96.3% 85.0% 66.2% 59.3% 56.7%

B_0352 1.82E‐08 8.16E‐09 2.16E‐09 2.16E‐09 1.32E‐09 92.6% 83.7% 39.1% 39.1% 0.0%

B_0353 1.82E‐08 8.16E‐09 2.16E‐09 2.16E‐09 1.32E‐09 92.6% 83.7% 39.0% 39.0% 0.0%

B_0354 1.82E‐08 8.13E‐09 2.13E‐09 2.13E‐09 1.29E‐09 92.8% 84.0% 39.6% 39.6% 0.0%

B_0356 1.84E‐08 8.24E‐09 2.13E‐09 2.13E‐09 1.29E‐09 91.6% 82.8% 39.6% 39.6% 0.0%

B_0357 1.84E‐08 8.24E‐09 2.15E‐09 2.15E‐09 1.29E‐09 91.6% 82.8% 39.3% 39.3% 0.0%

B_0358 1.95E‐08 8.81E‐09 2.31E‐09 2.28E‐09 1.41E‐09 86.4% 77.5% 36.6% 37.1% 0.0%

B_0359 2.79E‐08 8.24E‐09 2.16E‐09 2.16E‐09 1.30E‐09 94.5% 82.8% 39.0% 39.1% 0.0%

B_0360 1.88E‐08 8.62E‐09 2.55E‐09 2.54E‐09 1.69E‐09 89.8% 79.2% 33.2% 33.3% 0.0%

B_0361 1.84E‐08 8.24E‐09 2.15E‐09 2.15E‐09 1.30E‐09 91.6% 82.8% 39.3% 39.3% 0.0%

B_0362 1.71E‐08 6.96E‐09 8.62E‐10 8.61E‐10 2.76E‐12 98.5% 98.2% 98.0% 98.1% 0.0%

B_0363 1.84E‐08 8.18E‐09 2.16E‐09 2.16E‐09 1.32E‐09 91.5% 83.5% 39.0% 39.0% 0.0%

B_0364 1.82E‐08 8.16E‐09 2.16E‐09 2.16E‐09 1.32E‐09 92.6% 83.7% 39.0% 39.0% 0.0%

C_0183 7.16E‐07 3.48E‐07 8.74E‐08 6.12E‐08 6.12E‐08 77.5% 79.7% 56.2% 80.2% 80.2%

C_0184 1.06E‐06 4.71E‐07 2.43E‐07 1.74E‐07 1.74E‐07 83.5% 83.6% 82.7% 82.9% 82.9%

C_0185 1.18E‐07 1.18E‐07 1.18E‐07 1.18E‐07 1.18E‐07 0.0% 0.0% 0.0% 0.0% 0.0%

C_0186 1.99E‐08 1.99E‐08 1.99E‐08 1.99E‐08 1.99E‐08 0.0% 0.0% 0.0% 0.0% 0.0%

C_0188 1.91E‐07 3.08E‐09 1.76E‐09 1.29E‐09 1.29E‐09 97.4% 0.0% 0.0% 0.0% 0.0%

C_0189 1.82E‐09 3.11E‐10 0.00E+00 0.00E+00 0.00E+00 0.0% 0.0% 0.0% 0.0% 0.0%

Total/Avg. 1.26E‐05 4.42E‐06 1.36E‐06 1.25E‐06 5.79E‐07 65.9% 59.3% 46.6% 45.4% 32.9%

Source ID

CDF HGL
EXAMPLES OF ENCLOSURE FIRE ANALYSIS 

F-36 

1 F.2.5 Conclusions 

2 The revised guidance provided in RACHELLE_FIRE can be implemented effectively and can 

3 provide significant improvement in the fire risk of actual plant configurations. The amount of 

4 reduction from using the previous guidance will vary based on specific compartment and 

5 scenario parameters. Some specific insights are listed below. 

6 

7  The new guidance can result in significantly reduced severity factors. This reduction is a 

8 direct result of reduced HRRs. This effect is pronounced for the non-power oriented 

9 functional classification groups (4a-4c), as most of the distributions are weighted more 

10 toward the lower end than in the previous guidance. 

11  Accounting for cabinet effects such as the obstructed plume nature of fires in closed 

12 cabinets provides significant reduction in the calculated vertical ZOI, and SF. Previous 

13 guidance treated the source fires as open fires. The new guidance addresses cases 

14 where the fire is inside of an enclosure. 

15  Reduction of the horizontal ZOI had the most impact in screening additional targets. 

16 This is primarily due to fire growth considerations involving secondary combustibles that 

17 have a greater impact on targets above the source rather than to the sides. 

18  Fire growth due to propagation of secondary combustibles may still drive results, 

19 especially if HGL is possible. The reduced HRRs and revised guidance had very little 

20 impact on fire propagation in cable trays. 

21  Inspection of cabinet internals can result in significant benefits for risk reduction. Control 

22 cabinets vary greatly. By opening the cabinets and inspecting the internal configuration, 

23 reduced HRRs can be justified in many instances. 

24  This example also provided some insights into the significance of applying refined fire 

25 modeling methods including a source specific fire size. Although bounding fire sizes 

26 may be more efficient to use for initial walkdowns and target selection, significant 

27 benefits can be obtained in many scenarios by applying source specific fire sizes. 

28  Applying the RACHELLE_FIRE guidance can provide useful insights for decisions 

29 regarding the need or justification of installing modifications. 

30 

31 

32 






NUREG-2178, Vol. 1

Draft

Refining And Characterizing Heat Release Rates From Electrical

Enclosures During Fire (RACHELLE-FIRE)