Smoke Component Yields from Room-scale Fire Tests

NIST Technical Note 1453 

NIST Technical Note 1453 

Smoke Component Yields from Room-scale Fire Tests

Richard G. Gann 

Jason D. Averill 

Erik L. Johnsson 

Marc R. Nyden 

Richard D. Peacock 

Fire Research Division 

Building and Fire Research Laboratory 

National Institute of Standards and Technology 

Gaithersburg, MD 20899-8664

April 2003 

U.S. Department of Commerce 

Donald L. Evans, Secretary 

Technology Administration

Phillip J. Bond, Under Secretary for Technology

National Institute of Standards and Technology 

Dr. Arden L. Bement, Jr., Director
National Institute of Standards U.S. Government Printing Office For sale by the 

and Technology Washington: 2002 Superintendent of Documents 

Technical Note 1453 U.S. Government Printing Office 

Natl. Inst. Stand. Technol. Washington, DC 20402-9325

Tech. Note 1453 

159 pages (April 2003) 

CODEN: NTNOEF 
ABSTRACT 

This report presents the methodology for and results from a series of room-scale fire tests to 

produce data on the yields of toxic products in both pre-flashover and post-flashover fires. The 

combustibles examined were: a sofa made of upholstered cushions on a steel frame, 

particleboard bookcases with a laminated finish, polyvinyl chloride sheet, and household electric 

cable. They were burned in a room with a long adjacent corridor. The yields of CO2, CO, HCl, 

HCN, and carbonaceous soot were determined. Other toxicants (e.g., NO2, formaldehyde and 

acrolein) were not found; concentrations below the detection limits were shown to be of limited 

toxicological importance relative to the detected toxicants. The toxicant yields from sofa 

cushion fires in a closed room were similar to those from pre-flashover fires of the same

cushions in a room with the door open. The uncertainties in the post-flashover data are smaller 

due to the higher species concentrations and the more fully established upper layer from which 

the fire effluent was sampled. The uncertainty values are comparable to those estimated for the 

fractional effective dose calculations used to determine the time available for escape from a fire. 

The uncertainty in the yield data from the sofa, bookcase, and cable tests is sufficiently small to 

determine whether a bench-scale apparatus is producing results that are similar to or different 

from the real-scale results here. The use of Fourier transform infrared (FTIR) spectroscopy was 

shown to be a useful tool for obtaining concentration data of toxicants. However, its operation 

and interpretation is far from routine. The losses of CO, HCN, and HCl as they flowed down the 

corridor were found to be dependent on the combustible. The downstream to upstream 

concentration ratios varied from unity for some fuels to a factor of five smaller for others. The 

CO yield from two of the combustibles was significantly lower than the expected value of 0.2, 

which should be used in hazard and risk analyses. The accuracy of the results is verified, and a 

hypothesis is offered for the lower CO yield values. 

Keywords: fire, fire research, smoke, room fire tests, fire toxicity, smoke toxicity 

iii 
Disclaimer

Certain commercial entities, equipment, or materials may be identified in this document in order 

to describe an experimental procedure or concept adequately. Such identification is not intended 

to imply recommendation or endorsement by the National Institute of Standards and Technology,

nor is it intended to imply that the entities, materials, or equipment are necessarily the best 

available for the purpose. 

iv 
TABLE OF CONTENTS

LIST OF FIGURES .................................................................................................. viii 

LIST OF TABLES ......................................................................................................ix

EXECUTIVE SUMMARY ...........................................................................................xi

I. INTRODUCTION.................................................................................................. 1 

II. EXPERIMENTAL INFORMATION........................................................................ 3 

A. General Description .......................................................................................... 3 

B. Fire Test Configuration ..................................................................................... 3 

1. Room Construction........................................................................................ 3 

2. Load Cells ..................................................................................................... 7 

3. Sampling Ports .............................................................................................. 7 

4. Ignition Burners ............................................................................................. 9 

C. Test Specimens ................................................................................................ 9 

1. “Sofas”......................................................................................................... 14 

2. Bookcases................................................................................................... 16 

3. Rigid PVC sheeting ..................................................................................... 17 

4. Electric power cable .................................................................................... 17 

D. Test Plan......................................................................................................... 19 

E. Measurements and Sampling Methods........................................................... 26 

1. Exhaust Duct Quantities.............................................................................. 26 

2. Temperature................................................................................................ 26 

3. Doorway Velocity......................................................................................... 27 

4. Sample Delay Times ................................................................................... 27 

5. Sample Mass............................................................................................... 28 

6. CO, CO2, and O2 Concentrations ................................................................ 29 

7. Gas Sampling for FTIR and Ion Chromatographic Analyses....................... 29 

8. FTIR Analysis .............................................................................................. 31 

9. Acid Gas Analysis by Ion Chromatography ................................................. 34 

10. Smoke Mass................................................................................................ 35 

11. Heat flux ...................................................................................................... 36 

v 
12. Video ........................................................................................................... 36 

13. Additional Data............................................................................................ 36 

F. Data Collection................................................................................................ 36 

1. Hardware..................................................................................................... 36 

2. Event Marking ............................................................................................. 37 

3. On-the-fly conversions ................................................................................ 37 

4. Real time presentation ................................................................................ 37 

5. Storage for analysis..................................................................................... 38 

G. Test Procedure ............................................................................................... 38 

III. CALCULATION METHODS................................................................................ 41 

A. Heat Release Rate.......................................................................................... 42 

B. Mass Loss Rate .............................................................................................. 43 

C. Combustion Efficiency .................................................................................... 43 

D. Doorway Flows ............................................................................................... 43 

E. Global Equivalence Ratio................................................................................ 44 

F. Notional Gas Yields ........................................................................................ 44 

F. Measured Gas Yields...................................................................................... 45 

G. Smoke Yields.................................................................................................. 46 

IV. RESULTS........................................................................................................... 49 

A. Pre- and Post-flashover Time Intervals .............................................................. 49 

B. Test Data ........................................................................................................ 50 

C. Checks on Data Reliability .............................................................................. 71 

1. Cross-instrument Similarity.......................................................................... 71 

2. Location Similarity ....................................................................................... 71 

3. Notional Yield Fractions............................................................................... 72 

D. Test Repeatability............................................................................................... 72 

E. Species Losses During Transport....................................................................... 75 

F. Estimates of Toxic Gas Yields with Uncertainties............................................... 76 

G. Archiving of Test Data........................................................................................ 76 

V. DISCUSSION ..................................................................................................... 79 

A. Overall Test Quality ........................................................................................ 79 

vi 
B. Test Repeatability ........................................................................................... 79 

C. Species Sampling and Measurement ............................................................. 80 

1. CO2 and CO ................................................................................................ 80 

2. HCl and HCN............................................................................................... 81 

3. Other Gases ................................................................................................ 82 

4. Species Measurement Using FTIR Spectroscopy ....................................... 83 

D. Combustion Conditions................................................................................... 83 

E. Loss of Acid Gases During Transport ............................................................. 84 

F. Yield Values.................................................................................................... 84 

G. Use of the Results........................................................................................... 86 

VI. CONCLUSION.................................................................................................... 89 

VII. ACKNOWLEDGMENTS ......................................................................................... 91 

APPENDIX A. GRAPHS OF TEST DATA.................................................................... 92 

REFERENCES............................................................................................................ 137 

vii 
LIST OF FIGURES 

Figure 1. Schematic of the Room-corridor Test Fixture ........................................4 

Figure 2. Photograph of the Exterior of the Room-corridor Test Fixture ...............4 

Figure 3. Photograph of the Interior of the Room-corridor Test Fixture .................5 

Figure 4. Simulation of a Sofa Fire Using FDS......................................................6 

Figure 5. Photographs of Sampling Probes ...........................................................8 

Figure 6. Photograph of 8-cushion Sofa ..............................................................23 

Figure 7. Photograph of 12-cushion Sofa ............................................................23 

Figure 8. Photograph of 14-cushion Sofa ............................................................24 

Figure 9. Photo of V-oriented Bookcases in the Burn Room ...............................24 

Figure 10. Photograph of Bookcases and PVC Sheet in the Burn Room25 ..........25 

Figure 11. Photograph of Cable Trays in the Burn Room......................................25 

Figure 12. Schematic of Bi-directional Velocity Probes .........................................28 

Figure 13. Photograph of the FTIR Spectrometers................................................31 

Figure 14. Representative Spectrum of the Fire Gases Extracted during a Test ..33 

Figure 15. Mass Loss vs. Time: Tests SW10 through SW14.................................73 

Figure 16. Mass Loss vs. Time: Tests SW1 through SW3.....................................73 

Figure 17. Time-integrated Yields for Closed-Room Test SC1..............................74 

Figure 18. Time-integrated Yields for Closed-Room Test SC2..............................74 

Figure 19. Oxygen Concentration in Closed Room Tests......................................75 

viii 
LIST OF TABLES 

Table 1. Description of Four-probe Sampling Arrays............................................7 

Table 2. Elemental Analysis of Fuels .................................................................11 

Table 3. Elemental Analysis of Fuel Components ..............................................13 

Table 4. Heats of Combustion of Fuels .............................................................13 

Table 5. Mass and Mass Fraction of Cushion Components ...............................14 

Table 6. Mass and Mass Fraction of Electrical Power Cable Components ........18 

Table 7. List of Room Fire Tests.........................................................................21 

Table 8. Instrument Delay Times and Standard Deviations ...............................28 

Table 9. Calibration Spectra for FTIR Spectroscopy ..........................................34 

Table 10. Estimated Notional Yields of Toxic Products (mass fraction)................45 

Table 11. Time intervals (s) over Which Analyses Were Performed.....................52 

Table 12. Occurrence and Consequences of Malfunctioning Instruments ...........53 

Table 13A. Pre-flashover Test Results: Mass Loss Rates and Doorway Flows .....55 

Table 13B. Pre-flashover Test Results: Volume Fractions of Product Gases at 

Locations 1 and 2 ................................................................................56 

Table 13C. Pre-flashover Test Results: Volume Fractions of Product Gases at 

Locations 3 and 4 ................................................................................57 

Table 14A. Post-flashover Test Results: Mass Loss Rates and Doorway Flows ...58 

Table 14B. Post-flashover Test Results: Volume Fractions of Product Gases at 

Locations 1 and 2 ................................................................................59 

Table 14C. Post-flashover Test Results: Volume Fractions of Product Gases at 

Locations 3 and 4 ................................................................................60 

Table 15. Yields of Combustion Products for Open Room Tests ........................61 

Table 16. Yields of Combustion Products from Closed Room Tests ....................62 

Table 17. Smoke Yields........................................................................................63 

Table 18. Combustion Characterization ...............................................................64 

Table 19. NDIR/FTIR Volume Fraction Ratios .....................................................65 

Table 20. Ratios of Concentrations: 

Position 4 (Downstream)/Position 2 (Upstream)...................................66 

ix 
Table 21. Fractions of Notional Yields ..................................................................67 

Table 22a. Variance in Product Yields Among Replicate Tests (SW 10 to SW14).68 

Table 22b. Variance in Product Yields Among Replicate Tests (SW 1 to SW3).....68 

Table 23a. Uncertainties in FTIR Volume Fractions of Product Gases; 

 Pre-flashover Data................................................................................69 

Table 23b. Uncertainties in FTIR Volume Fractions of Product Gases; 

 Post-flashover Data .............................................................................70 

Table 24. Ratios of Downstream to Upstream Concentrations 

 (Post-flashover Data)............................................................................75 

Table 25. Yields of Combustion Products Calculated from Location 2 Data.........77 

Table 26 Fraction of Combustible Carbon Appearing in Carbon Monoxide.........78 

Table 27 Limits of Importance of Undetected Toxicants......................................82 

x 
EXECUTIVE SUMMARY 

This report presents the methodology and results of Phase IIa of the International Study of 

Sublethal Effects of Fire Smoke on Survivability and Health (SEFS) project of the Fire 

Protection Research Foundation and the National Institute of Standards and Technology. The 

SEFS is a private/public fire research initiative to provide the scientific information for public 

policy makers to determine whether, when and how to incorporate the sublethal effects of heat 

and smoke in their fire safety decisions. The objective of this portion of the SEFS project is to 

establish a technically sound basis for assessing the accuracy of the bench-scale device(s) that 

will be generating smoke yield data for fire hazard and risk evaluation. 

Estimation of the time people will have to escape or find a place of refuge in the event of a fire is 

a principal component in the fire hazard or risk assessment of an occupancy. Accurate 

assessment enables public officials and facility owners to provide a selected or mandated degree 

of fire safety with flexibility of design and confidence in the outcome, while imprecise 

assessment can result in increased cost and elimination of otherwise desirable building and 

furnishing products. 

The computation in such an assessment involves the building design, the capabilities of the 

occupants, the potential growth rate of a fire and the spread rate of the heat and smoke, and the 

impact of the fire effluent (toxic gases, aerosols, and heat) on people in the fire vicinity. 

Increasing attention is being paid to the effects of the effluent on responders to a fire. The 

equations in ISO/TS 13571 now enable estimating the time available for escape. The approach 

to input data for such calculations is being addressed with the current work. 

These data typically come from one of several, very different bench-scale combustors. Thus 

there can be diverse and perhaps conflicting data on fire effluent component yields available for 

any given product. Only one device (NFPA 269/ASTM E1678) has been validated against realscale fire test data, and then only for post-flashover yields of the principal toxicants. This 

situation does not support either assured fire safety or marketplace stability. Thus, the need for a 

standard methodology for establishing the accuracy of these methods is critical to the credibility 

of fire hazard and risk assessments. 

We report the results of room-scale fire tests. Various complex products were subjected to the 

key stages of a fire: well-ventilated flaming combustion and ventilation-limited (post-flashover) 

flaming combustion. Each test and fire phase included characterization of the fire and 

calculation of the yields of toxic gases and smoke. Since some of the toxicants might be 

removed from the inhalable environment, we estimated a degree of loss of each. Where the 

concentration was too low to be measured, an upper limit was estimated. 

A future effort is being planned in which the same fuels are combusted in typical bench-scale 

apparatuses under combustion conditions appropriate to well-ventilated and ventilation-limited 

burning. The information generated in these real-scale fire tests then comprises the basis for 

assessing the accuracy of the yields from the various bench-scale devices. 

xi 
Four combustibles were burned in a 2.44 m x 2.44 m x 3.66 m room whose only vent was an 

0.76 m wide doorway leading to a 9.75 m long, open-ended corridor. In some tests, a panel was 

removed from the corridor ceiling 1.22 m downstream from the burn room, and the room

effluent exhausted into a collection hood for heat release rate measurement. The optimal vent 

location was identified using Fire Dynamics Simulator (FDS) version 2.0, a computational fluid 

dynamics model employing large-eddy simulation techniques. The choice was for the nearest 

location at which the flame reaction was over before the effluent reached the vent location and 

where entrainment of dilution of the combustion products with corridor was minimized. Two 

tests were conducted with the door of the burn room closed. 

The ignition modes and test configurations were selected to provide burning durations (under 

both pre-flashover and post-flashover conditions) that were long enough for substantive 

combustion product analyses. In some cases, adherence to realism was sacrificed to achieve this. 

The four combustibles were: 

• “Sofas” made of up to 14 upholstered cushions supported by a steel frame. A 46 cm x 46 

cm x 15 cm cushion consisted simply of a zippered cotton-polyester fabric over a block 

of foam. The elemental content of the cushions was (% by mass) 54.5 % C, 8.0 % H, 

10.0 % N, 0.68 % Cl, 0.15 % P, and 26.7 % O. The mass of a cushion was about 1.1 kg 

and the heat of combustion was 24.4 MJ/kg ± 2.7 %. The California TB133 propane 

ignition burner faced downward, centered over the center of the sofa, about 10 cm above 

the top surface of the cushions. In all but two of the tests, the sofa was centered along the 

rear wall of the burn room facing the doorway. In two tests, the sofa was placed in the 

middle of the room facing away from the doorway to compare the burning behavior 

under different air flow conditions. Two of the sofa tests were in a closed room to 

examine the effect of vitiation. In these, an electric “match” was used to initiate the fires 

in the closed compartment tests. 

• Particleboard (wood with urea formaldehyde binder) bookcases with a laminated vinyl 

finish. The bookcases were 1.83 m high x 0.91 m wide x 0.30 m deep. The back of the 

bookcase was a sheet of vinyl-laminated pressboard. The bookcase mass was ca. 27.5 

kg. A diagonal length of steel angle iron was attached to the rear of the bookcases to 

prevent buckling and falling off the load cell during the test. The chemical analyses of 

the bookcases indicated a composition of 48.1 % C, 6.2 % H, 2.9 % N, 0.3 % Cl, and 

42.6 % O. The heat of combustion was 18.16 MJ/kg ± 0.4 %. Early experiments with 

two bookcases side by side and the burner in between failed to sustain burning. As a 

result, two bookcases were placed in a “V” formation, with the TB133 burner facing 

upward approximately 30 cm under the lower shelves and 30 cm from the back of the 

“V.” 

• Rigid polyvinyl chloride (PVC) product sheet (a window frame material). Each test 

involved a single horizontal sheet of unplasticized PVC that was 0.71 m x 1.83 m x 7.9 

mm in the room with burning bookcases. The elemental composition of the combustible 

portion of the sheet was 42.3 % C, 5.53 % H, and 52.2 % Cl. The measured heat of 

combustion was 16.17 kJ/kg ± 1.0 %. 

xii 
• Household wiring cable, consisting of two 14 gauge copper conductors insulated with 

nylon and PVC, an uninsulated ground conductor, two paper filler strips, and an outer 

jacket of plasticized PVC. We estimated the fuel composition to be 45.8 % C, 6.2 % H, 

1.62 % N, 25.2 % Cl, and 20 % O. The heat of combustion for the combustible fraction 

of the cable was 21.60 MJ/kg ± 0.6 %. Two 1.83 m long cable racks containing 3 trays 

each were constructed, with 30 kg of cable in each of the bottom two trays and 17 kg in 

each of the middle and top trays. The cable trays were placed parallel to the rear of the 

burn room. Twin 152 mm square propane ignition burners were centered under the 

bottom tray of each rack. 

Supplies of each of the test fuels were stored for future use in bench-scale test method 

assessment. 

The mass of each test specimen was monitored continuously. The concentrations of CO2, CO 

and O2 were monitored in the burn room and at three locations in the corridor using speciesspecific analyzers. Fourier transform infrared (FTIR) spectroscopy was used to monitor CO2, 

CO, HCN, HCl, HF, HBr, NO, NO2, H2CO (formaldehyde), and C3H4O (CH2=CH-CH=O, 

acrolein) at the upstream and downstream ends of the corridor. We were unsuccessful at 

determination of HCl, HCN, NO and NO2 yields using a wet chemical technique. Soot was 

measured gravimetrically at the same two locations. All measurements were intended to be in 

the upper smoke layer, 30 cm from the ceiling. In the two tests with the doorway blocked, the 

effluent was sampled from the upper layer of the burn room. Additional measurements were 

made of the vertical temperature and pressure profiles in the doorway (for effluent flow 

calculation), CO, CO2, and O2 and flow in the exhaust hood (for heat release rate calculations), 

heat flux to the burn room floor (as a measure of flashover). All tests were videotaped within the 

burn room and down the corridor. 

 

Following preliminary experiments to identify the ignition protocol, determine the mass of fuel 

needed to produce flashover, and measure the rate of heat release and rate of mass loss, 22 tests 

were then performed as follows: 

 Three tests with an 8- or 12-cushion sofa. These tests did not proceed to flashover, but 

generated additional data for pre-flashover conditions.

 Five replicate tests with a 14-cushion sofa located against the back wall of the burn room, 

facing the open doorway. The intent was to provide an estimate of test repeatability.

 Two tests with the sofa against the back wall, but with the doorway blocked, to determine 

the effect of room vitiation.

 Seven tests of two bookcases each.

 Three similar bookcase tests with the rigid PVC sheeting product.

 Two tests of electric cable in the tray assembly.

xiii 

The data from all the sensors (except the FTIR spectrometers) were collected electronically at 

200 scans/s and smoothed to a rate of 1 sample/s. Channel markers kept track of the key events 
during a fire test. The FTIR data were recorded unsmoothed on a separate computer. All of the 

raw data (ca. 130 instruments, thousands of readings per instrument) from the tests reported here 

are to be available in a companion report. This will be in the form of spreadsheets and graphs. 

For the open-door tests, the yields of the gases were determined by defining the pre- and postflashover time intervals, determining the test specimen mass loss and the average volume

fractions of the gases during those intervals, calculating the pre- and post-flashover yields of CO2

from the above plus the calculated total mass flow through the doorway, and determining the 

yields of the other gases using their mass fraction ratios to the mass fraction of CO2. 

For the closed-room tests, we assumed that the upper layer was well mixed. The measured 

volume fractions of the gases and the ideal gas law were used to calculate the mass of each 

species in the upper layer. These were normalized to specimen mass loss, as a function of time. 

For the PVC sheets, only post-flashover results were possible since the mass loss was negligible 

before flashover. It was assumed that all the HCl was from the PVC sheet and all the HCN came 

from the bookcases. Since the scatter in the CO and CO2 yields was comparable to any 

differences between tests with and without the PVC sheet, yield data for these two gases from

the PVC sheet were not calculable. 

 

The uncertainty in the yield values results from the sensitivity of the yield to the selected time 

pre- or post-flashover time interval, the uncertainty in the specimen mass loss, the uncertainty in 

the species mass flow out the doorway (for open door tests), and the quality of the assumptions 

inherent in the calculation of the mass of product in the upper layer (for closed room tests). For 

the closed room tests, the uncertainty was further estimated by comparing the yield values from

the early combustion with those from the pre-flashover segments of the open door sofa tests. 

The analysis of similar tests also structured the determination of uncertainty and repeatability. 

Some of the data were not used because an instrument malfunctioned, the upper layer 

(containing the combustion products) did not fully envelop the sampling probe tips, or the 

concentration values were too close to the background levels. 

We were able to obtain usable information using FTIR spectroscopic analysis. We note that its 

application to fire testing requires the constant attention of an experienced professional at a level 

well beyond the demands of the more traditional fire test instrumentation. 

Initial checks on the consistency of the upstream post-flashover and late pre-flashover 

measurements showed the non-dispersive infrared (NDIR) and FTIR instruments gave similar 

concentrations of CO and CO2 and low variability. Distinctly higher variability was found 

during the general pre-flashover burning periods for all tests. The pre-flashover sampling time

period was adjusted such that the probe tip was sampling from the upper layer. The FTIR preflashover measurements were consistently smaller than those using NDIR for reasons not yet 

understood. The downstream pre-flashover CO measurements approached the detection limits of 

the analyzers. For the closed room tests, the early NDIR yields for CO2 and CO were close to 

xiv 
those for the open door sofa tests. As the fire progressed, the CO2 yield decreased and the CO 

yield increased, as expected from burning in an increasingly vitiated atmosphere. 

Many HCl and HCN measurements were very close to the background. Nonetheless, the data 

were sufficient to obtain reasonable post-flashover yield values and pre-flashover yield estimates 

for all three principal combustibles. The HCl concentration data for the PVC sheet were high 

enough to obtain a post-flashover HCl yield. The post-flashover HCl and HCN concentrations 

were also high enough to obtain estimates of the degree of loss of the compounds down the 

length of the corridor. The pre-flashover values had too high a degree of uncertainty for this use. 

The equations in ISO/TS 13571 include additional gases to be included in estimating the time

available for escape or refuge from a fire. The composition of the combustibles precluded the 

formation of some of these. Three key sensory irritants (NO2, acrolein and formaldehyde) were 

not detected, thus establishing the upper limits of their presence at 100, 10, and 50 x 10-6 volume 

fraction, respectively. Analysis of these levels in light of their incapacitation concentrations 

from ISO/TS 13571 showed they would have had secondary contributions to incapacitation 

relative to the concentration of HCl, except in the case of the bookcases, which produced little 

HCl. This unimportance of secondary toxicants is consistent with the results of the animal 

experiments used to establish the N-gas hypothesis that attributes fire effluent lethality to a mall 

number of gases. 

 

The following table presents the results of the measurements and calculations for yields of 

principal toxicants for both pre-flashover and post-flashover fires: 

Gas Fire 

Stage Sofa Bookcase PVC Sheet Cable

Pre-fl. 1.59 ± 25 % 0.50 ± 50 % -- 0.120 ± 45 % 

CO2

Post-fl. 1.13 ± 25 % 1.89 ± 75 % -- 1.38 ± 15 % 

Pre-fl. 1.44 x 10-2 ± 35 % 2.4 x 10-2 ± 55 % -- 5.5 x 10-3 ± 50 % 

CO 

Post-fl.* 5.1 x 10-2 ± 20 % 4.6 x 10-2 ± 30 % -- 1.48 x 10-1 ± 15 % 

Pre-fl. 3.5 x 10-3 ± 50 % 4.6 x 10-4 ± 10 % -- 6.3 x 10-4 ± 50% 

HCN 

Post-fl. 1.5 x 10-2 ± 25 % 2.5 x 10-3 ± 45 % -- 4.0 x 10-3 ± 30 % 

Pre-fl. 1.8 x 10-2 ± 45 % 2.2 x 10-3 ± 75 % -- 6.6 x 10-3 ± 35 % 

HCl 

Post-fl. 6.0 x 10-3 ± 35 % 2.2 x 10-3 ± 65 % 2.3 x 10-2 ± 85 % 2.1 x 10-1 ± 15 % 

Pre-fl. < 7 x 10-2 < 2 x 10-2 -- < 4 x 10-3

NO2

Post-fl. < 1 x 10-3 < 1 x 10-3 -- < 1 x 10-3

Pre-fl. < 8 x 10-3 < 2 x 10-3 -- < 4 x 10-4

Acrolein

Post-fl. < 1 x 10-4 < 1 x 10-4 -- < 1 x 10-4

Pre-fl. < 2 x 10-2 < 2 x 10-3 -- < 8 x 10-4

Formalde

hyde Post-fl. < 8 x 10-4 < 4 x 10-4 -- < 7 x 10-4

* See following discussion.

xv 
One check on the accuracy of the measurements was to compare calculated yields with the 

notional or maximum possible yields. Near-quantitative conversion of C and Cl in the fuel to 

CO2 and HCl was expected. The post-flashover values of CO2 from all three combustibles did 

just that, given the conversion of up to ca. 20 % of the carbon to carbonaceous smoke and CO. 

Under pre-flashover conditions, the yields were more variable. In the closed room tests, the 

yield began at about the notional level, then declined to about half that as room vitiation affected 

the completeness of combustion. The HCl yields were close to notional under post-flashover 

conditions for all the combustibles. Very low pre-flashover values for the electrical cable well 

reflect the known HCl reaction with the calcium carbonate filler in the cable jacket. While little 

of the nitrogen in the combustibles generally ended up in HCN, there was an over 10 % 

conversion from the post-flashover burning of the bookcases and cable. 

 

The repeatability of the sofa tests was excellent: qualitative agreement of the shapes of the mass 

burning rate curves, similar global equivalence ratios, and low variability (± 25 %) in the postflashover yields of CO2, CO, and HCN were within ± 25 % and are within ± 35 % for HCl. The 

pre-flashover yield values were repeatable to within a factor of two. For the sofa tests that did 

not reach flashover, the mass burning rate curves were also similar and the later pre-flashover 

CO2, CO and HCl yields were repeatable to within ± 36 %, with the HCN yield repeatable to 

within ± 45 %. The yields from the two closed room sofa tests were repeatable to within ± 20 %. 

The four cable tests showed qualitatively similar results. Post-flashover yield repeatability was 

typically ± 15 % to 30 %, with the pre-flashover repeatability somewhat higher but within a 

factor of two. For the four bookcase tests in which NDIR data were obtained, the post-flashover 

and pre-flashover yield repeatability values for CO2 were ca. ± 75 % and ± 30 %, respectively; 

the CO values are ca. ± 30 % and ± 55 %. For the two bookcase tests for which we obtained 

FTIR data, the HCN post-flashover and pre-flashover yield repeatability values were ca. ± 45 % 

and 10 %, respectively, and the HCl values are 65 % and 75 %. The post-flashover HCl yields 

from the three PVC sheet tests spanned over an order of magnitude. 

Of particular interest are the post-flashover yields of CO. A number of room-scale fire studies 

have indicated that the yield of CO is approximately 0.2 (g CO/g fuel consumed) and that this 

value is not very dependent on the combustible. In this study, the post-flashover CO yields from

the cable fires approach this, with a mean of ca. 0.15 g/g. The sofas and bookcases generate 

about one quarter of the expected value. 

We performed a number of checks to assure the accuracy of the CO yields. We verified the tests 

truly reached flashover. By comparison with CO levels within the burn room, we ascertained 

that the CO was not being oxidized in the secondary burning at the doorway. Experimental 

errors of a sufficient magnitude are highly unlikely, since two different types of analyzers with 

independent sampling lines produced comparable CO yields. The same calculations produced 

CO2 yields near the notional limits, so there cannot be a missing factor in the data reduction. 

A likely hypothesis is that large quantities of pyrolyzate are generated during flashover. These 

consume the limited available oxygen, forming CO, but leaving much of the organic matter 

xvi 
unoxidized. As these gases reach the doorway and begin to entrain fresh air, more of the organic 

matter is oxidized to CO. Some of the CO is also oxidized to CO2. Combined, these processes 

set up a dynamic situation where the observed [CO]/[CO2] ratio and the yield of CO depend on 

the degree of air-effluent mixing and the rate of cooling of the total flow. Since different fires 

and different stages of those fires are likely to be accompanied by differing degrees of CO 

formation and burnout, we suggest that for fire hazard and risk assessments, one should use the 

CO yield value of 0.2 g CO per g fuel consumed. Since bench-scale combustors typically used 

for generating toxic potency data generally do not have the potential for the secondary 

combustion processes described above, the 0.2 g/g value should also be used for assessing the 

accuracy of the data from such apparatus. 

In summary, the repeatability of the yields values obtained in this study for three of the 

combustibles is sufficient for determination of whether a bench-scale apparatus is producing 

results that are similar to or different from the real-scale results here. The PVC sheet, from

which only HCl yield data could be obtained, can only provide an indicator of appropriateness 

and then only for post-flashover simulation. 

Since a large fraction of fire deaths result from post-flashover fires and since CO is always a 

major (if not the dominant) incapacitating toxicant, the repeatability results indicate an

uncertainty in the fractional effective dose (FED) calculations that is comparable to the 

uncertainty in the equations themselves. The repeatability values should also be sufficient to 

determine whether a bench-scale apparatus is producing results that are similar to, or different 

from the real-scale results obtained in this study. 

The loss of combustion products as they traveled down the corridor was quantified by the ratio of 

their upstream to downstream concentration ratios. Since CO2 is inert, its ratio was used as a 

measure of dilution of the upper layer effluent with entrained lower layer air. Only postflashover data were used due to the low values of the pre-flashover concentrations downstream. 

The losses of CO, HCN, and HCl were found to be dependent on the combustible. The 

downstream to upstream concentration ratios varied from unity for some fuels to a factor of five 

smaller for others. The cause of this is not understood. However, soot particles and aqueous 

aerosols are characterized by their number density, surface area, and hydrophilia. In these tests, 

only the soot mass was measured. It may well be that the smoke from the sofa and cable 

materials has a greater affinity for acid gases and CO than does the smoke from the bookcases 

and PVC sheet. However, for some other combustibles, loss factors of two to five beyond 

dilution are possible. Care should be taken not to extend these limited findings to other 

commercial products. Pending a comprehensive study of the relationship between smoke 

character and gas absorption, safety engineers are most likely to continue to assume there is no 

loss of toxicants, the more conservative approach. 

The research was co-sponsored by the Alliance for the Polyurethane Industry, the American 

Plastics Council, DuPont, Lamson & Sessions, Underwriters Laboratories, and the Vinyl 

Institute under the aegis of the Fire Protection Research Foundation. 

xvii 
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xviii 
I. INTRODUCTION 

This report presents the methodology and results of Phase IIa of the International Study of 

Sublethal Effects of Fire Smoke on Survivability and Health (SEFS) project of the Fire 

Protection Research Foundation and the National Institute of Standards and Technology. The 

SEFS is a private/public fire research initiative to provide the scientific information for public 

policy makers to determine whether, when and how to incorporate the sublethal effects of heat 

and smoke in their fire safety decisions. The objective of this portion of the SEFS project is to 

establish a technically sound basis for assessing the accuracy of the bench-scale device(s) that 

will be generating smoke yield data for fire hazard and risk evaluation. 

Estimation of the time people will have to escape or find a place of refuge in the event of a fire is 

a principal component in the fire hazard or risk assessment of a facility. An accurate assessment 

enables public officials and facility owners to provide a selected or mandated degree of fire 

safety with confidence. An imprecise assessment can result in the regulator and/or designer 

applying large safety factors. These increase cost and can eliminate the consideration of 

otherwise desirable building and furnishing products. 

Fire safety assessments now rely on some type of computation that takes into account such 

factors as the building design, the capabilities of the occupants, the potential growth rate of a fire 

and the spread rate of the heat and smoke, and the impact of the fire effluent (toxic gases, 

aerosols, and heat) on people in the fire vicinity.1

 Increasing attention is being paid to the effects 

of the effluent on responders to a fire. 

The methodology for inclusion of fire effluent effects is presently ad hoc in nature, varying with 

the instance at hand and the person performing that portion of the safety assessment. The 

absence of a standard approach encourages conservatism while leaving questionable (both during 

the design process and in litigation following any mishap) the degree of safety provided. 

It would thus bring an improved order to the construction and furnishing marketplace if there 

were a standard means of estimating the threat posed by fire effluent. This requires a calculation 

method and input data to support the calculations. 

The first of these components is proceeding well: 

 CFAST and other computer models of the movement of fire effluent throughout a facility 

have been in use for nearly two decades.2

 A number of laboratory programs and 

reconstructions of actual fires have given credence to the predictions.3

 These models 

calculate the temperature and combustion product concentrations as the fire develops. 

They can include equations for estimating when a person would die or is incapacitated, 

i.e., is no longer available to effect his/her own escape. 

 Devices such as the Cone Calorimeter4

 and related larger scale apparatus5 are routinely

used to generate information on the rate of heat release as a commercial product burns. 

 With the adoption of ISO Technical Specification 13571, “Life Threat from Fires - 

Guidance on the Estimation of Time Available for Escape Using Fire Data,” there now 

exist consensus equations for estimating the incapacitating exposures to narcotic gases, 

1
irritant gases, heat and smoke.6

 Some of the basis for these equations lies in the prior 

effort under this project.7

The second of these components is addressed here. The equations in ISO/TS 13571 require data 

on the yields of the key combustion products from the various commercial products that might 

be involved in a fire. There has been, however, no standard methodology for routinely obtaining 

such yield data. Reliance on real-scale testing of commercial products is impractical for its 

expense per test and the vast number of commercial products used in buildings. 

Rather, there are numerous bench-scale devices that are intended for generating chemical or 

physical measurements of smoke components. The combustion conditions and test specimen 

configuration in the devices vary widely, and some devices have wide flexibility in setting those 

conditions. Only one of these devices, used in both NFPA 2698

 and ASTM E16789, has been 

validated against real-scale fire test data, and then only for post-flashover yields of the principal 

toxicants. Meanwhile, ISO and IEC are proceeding toward standardization of a tube furnace, 

and ISO TC92 SC1 will be upgrading the analytical capability for the closed box test used by 

IMO and perhaps other similar devices. Thus, before too long there will be diverse and perhaps 

conflicting data on fire effluent component yields available for any given product. This situation 

does not support either assured fire safety or marketplace stability. 

Thus, the need for a standard methodology for establishing the accuracy of these methods is 

critical to the accuracy and credibility of fire hazard and risk assessments. 

The approach to be taken is to conduct a series of room-scale tests. Various complex products 

(as contrasted with single, homogeneous materials) are subjected to the key stages of a fire: wellventilated flaming combustion and ventilation-limited (post-flashover) flaming combustion. The 

products are selected to generate the dominant toxicants. Each test and fire phase includes 

measurement of the mass yields (per mass of fuel consumed) of the principal combustion 

products contributing to lethal and sublethal effects of fire: heat, toxic gases, and particulates. 

The list of toxicants to be monitored was: CO2, CO, HCN, HCl, HF, HBr, NO, NO2, H2CO 

(formaldehyde) and C3H4O (CH2=CH-CH=O, acrolein). Where the concentration was too low to 

be measured, an upper limit was estimated. 

It is possible that some gases could be deposited on walls or soot as they travel away from the 

fire. Assuming no such losses could unduly penalize products containing, e.g., halogenated 

additives in hazard analyses. Comparison of the concentrations at the upstream and downstream

ends of the corridor provided some qualitative indication of the degree of loss of each gas. 

A future effort is being planned in which the same fuels are combusted in typical bench-scale 

apparatuses under combustion conditions appropriate to well-ventilated and ventilation-limited 

burning. The information generated in these real-scale fire tests then comprises the basis for 

assessing the accuracy of the yields from the various bench-scale devices. 

This report documents the room-scale experiments and the combustibles examined. It presents 

the combustion product yield data, their degree of repeatability, and the import of the findings. 

2
II. EXPERIMENTAL INFORMATION 

A. General Description 

Four combustibles were burned in a room whose only significant vent was a doorway leading to 

a corridor; the downstream end of the corridor was unconfined. There were two types of tests: 

 The first type was used to scope the burning behavior of the fuel and to guide the 

protocol for the second type of tests. A large hole in the corridor ceiling enabled 

measurements of CO2, CO and O2 concentrations to be made in the exhaust stack. 

 The second type of test was used to determine the yields of the toxic gases and to 

determine the extent to which the more reactive ones were lost to soot or wall surfaces. 

The concentrations of the above gases were measured at three locations in the upper layer 

of the corridor and in the upper layer of the burn room. The concentrations of other gases 

of toxicological interest were measured at two locations in the corridor using Fourier 

transform infrared (FTIR) spectroscopy. In order to support the information on acid 

gases obtained using FTIR spectroscopy, we attempted (unsuccessfully) independent 

determination of HCl, HCN, NO and NO2 yields using a wet chemical technique. 

Yields of the toxic gases were calculated using the consumed mass of the fuel, gas 

concentrations measured in the corridor, and data regarding the flow down the corridor. The loss 

of product gases was estimated from the difference between the downstream to upstream 

concentration ratio of the gas and the same ratio for CO2, whose concentration was presumed to 

change only by dilution. Gross measurements of soot density were made in order to enable 

future analysis of the observed losses. 

B. Fire Test Configuration 

1. Room Construction 

The tests were conducted in the two-compartment assembly shown schematically in Figure 1 and 

photographically in Figures 2 and 3. The interior of the burn room was 2.44 m wide, 2.44 m

high, and 3.66 m long (8 ft x 8 ft x 12 ft). The attached corridor was 9.75 m long (32 ft) and of 

width and height similar to the burn room. A doorway 0.76 m (30 in) wide and 2.0 m (80 in) 

high was centered in the common wall. The downstream end of the corridor was fully open, i.e., 

there was no end wall. The entire assembly was elevated 76 cm (30 in) on cinder block supports. 

During the first scoping tests, the walls and ceiling of the burn room and corridor were 

constructed of two layers of 1.27 cm (0.5 in) thick gypsum wallboard over wooden studs. After 

the tenth heat release test and prior to the first performance test (BW1, see Section II.D), the 

surface layer of gypsum board covering the walls and ceiling of the burn room was replaced with 

a single layer of calcium silicate board of the same thickness. As the test series progressed, this 

layer was spackled or replaced to keep smoke and heat leakage to a minimum.

3
Figure 1. Schematic of the Room-corridor Test Fixture 

Figure 2. Photograph of the Exterior of the Room-corridor Test Fixture 

4
Figure 3. Photograph of the Interior of the Room-corridor Test Fixture 

For the tests designed for the measurement of rate of heat release (containing a “Q” in the test 

designation, Section II.D), a 1.22 m wide and 2.44 m long (4 ft x 8 ft) corridor ceiling panel was 

removed from the corridor 1.22 m (4 ft) downstream from the burn room wall (Figure 1). The 

room effluent exhausted through this vent into a large (6 m x 6 m aperture) collection hood, 

which was fit with the instrumentation for heat release rate measurement.10 During the 

production tests, this vent was sealed, and the room effluent flowed the full length of the corridor 

to a large, uninstrumented exhaust hood. 

The optimal location for the vent was identified using Fire Dynamics Simulator (FDS) version 

2.0, a computational fluid dynamics model employing large-eddy simulation techniques.11 Four 

locations in the corridor ceiling were investigated. In each case, the vent width was the full 

width of the corridor, 2.44 m (8 ft), and the length was 1.22 m (4 ft). The fire in the calculations 

was a sofa fire that produced flashover. The nature and behavior of the fire plume exiting the 

doorway was calculated for each vent location, with a fifth computation simulating the same fire 

with no vent opening. 

5
 For the computation with no vent opening, the flames extending out the doorway 

impinged on the ceiling within about 1 m of the doorway plane and were quenched. 

 For the exhaust vent location 0 m to 1.22 m from the doorway, flames extended through 

the doorway and into the vent opening toward the calorimetry measurement hood. This 

unquenched chemistry could result in chemical composition of the effluent (and thus a 

rate of heat release) different from the later tests with no vent opening, an undesirable 

outcome. 

 For the exhaust vent location between 1.22 and 2.44 m downstream of the doorway, the 

modeling showed that the flame extension would not continue past 1.22 m downstream,

thus only quenched effluent flowed through the vent. 

 The model results for the exhaust vent location further downstream showed the same

desired flame quenching phenomena. However, the exhaust gases would travel further 

than the previous case, resulting in increased entrainment and mixing. The increased 

entrainment and mixing results in an undesirable temporal averaging of the heat release 

rate measurement. 

Thus, the exhaust vent for the corridor was located between 1.22 m and 2.44 m downstream of 

the doorway. 

Figure 4 is a visualization of the FDS simulations of a sofa fire with the exhaust vent closed. 

The orange area (or dark gray, if viewed in black and white) of the plume represents the surface 

of the flame sheet where the mixture fraction is 1, i.e., where fuel and oxygen are assumed to 

react stoichiometrically. Note that the flame reaction is over before the effluent reaches the 1.22 

m to 2.44 m vent location, while entrainment of corridor air has yet to dilute the combustion 

products appreciably. 

Two of the tests were carried out with the doorway blocked. In those cases, there was no venting 

of the effluent. Rather, the effluent accumulated in the upper layer of the room, from which it 

was sampled. 

Figure 4. Simulation of a Sofa Fire Using FDS

6
2. Load Cells 

Two load cells (described in Section II.E.3 below) were used to measure the specimen mass loss 

during the tests. The load cells were placed on the floor of the test bay below the burn room. 

The combustible was placed on a large metal pan that was in turn supported on a frame that 

transmitted the mass through holes in the burn room floor to the load cell. 

3. Sampling Ports 

Gases and soot were sampled at some or all of four locations. The tips of the single probes and 

the middle of the four-probe arrays were located on the corridor/burn room centerline, 

approximately 30 cm (1 ft) from the ceiling with the intent to avoid sampling from within a 

stagnant boundary layer but still capture combustion products from early, low-momentum

effluent flows. The tubing lengths of the two four-probe arrays were parallel, their tips forming a 

diamond 100 mm high and wide. The probes are shown in Figure 5 and described in Table 1. 

The axial locations were: 

 Single probe 1 m (3.3 ft) inside the burn room door. The desire was to obtain 

information on the fixed gases (CO2, CO, and O2) in the well-mixed, upper layer. For the 

tests with the burn room door closed, room gas was extracted from a similar adjacent port 

for FTIR analysis. 

 Four-probe array (see Section II.E.5 for more complete description), nominally 1 m (3.3 

ft) outside the burn room doorway. This location was selected to be in the upstream end 

of the quenched doorway jet, i.e., in a location where minimal entrainment of corridor air 

and dilution of the combustion products would have occurred following their leaving the 

burn room. For the more intense fire stages, the flames were not always quenched at this 

location. 

 Single probe 2.1 m (6.6 ft) downstream from the burn room doorway (30 cm (1 ft)

upstream of the heat release rate vent). The purpose of measurement at this location was 

to characterize the composition of the fixed gases just before they reached the exhaust 

vent. 

 Four-probe array nominally 9.4 m (30.8 ft) from the burn room door or approximately 1 

m (3.3 ft) upstream from the open end of the corridor. This location was selected in order 

to be as far down the corridor as possible, yet minimize edge effects at the end of the 

corridor. 

 

Table 1. Description of Four-probe Sampling Arrays

Probe Designation Probe Location Function 

T Top Pre-flashover soot

B Bottom Post-flashover soot

U Upstream FTIR analysis

D Downstream Fixed gases

7
Figure 5. Photographs of Sampling Probes 

5a. Corridor Interior

5a. Corridor Exterior 

8
4. Ignition Burners 

Two different propane burners were used as ignition sources for the test series. The first burner, 

the one for testing mattresses under California Technical Bulletin 133, was used for the sofa and 

bookcase tests. The burner is described in detail elsewhere.12 Briefly, it consists of a perforated 

square “ring” with an outer dimension of 0.25 m (0.8 ft) attached to a supply tube at the center of 

one side of the square. The burner ring and supply tube were made of 12.7 mm (1/2 in) diameter 

stainless steel. The supply tube was connected to a compressed gas cylinder containing propane 

via a 12.7 mm (0.5 in) flexible supply line. A valve and flowmeter were located just downstream

of the propane cylinder. 

 

The electrical cable was ignited using two 152 mm (6 in) square sand-filled steel burners 

connected at the centers of their bottoms by a 12.7 mm (0.5 in) steel pipe. Propane was supplied 

to the burners from a compressed gas cylinder through a flowmeter installed in the 12.7 mm (0.5 

in) supply line at a flow of 0.024 m3

/min (50 ft

3

/hr). 

To initiate the fires in the closed compartment tests, we fabricated an “electric match” as follows. 

The cover of a cardboard matchbook was bent backward, and a loop at one end of a length of 

small gauge nichrome wire was inserted through the sulfur ends of the matches. The other end 

of the wire was attached to a switched power source. When the switch was closed, the wire 

heated quickly, igniting the matchbook within 2 s. Since the matchbook burns out quickly, it 

was surrounded by a folded piece of paper to extend the flaming for approximately 20 s, 

ensuring ignition of the surrounding material. 

C. Test Specimens 

Four fuels were selected for diversity of physical form, combustion behavior, and the nature and 

yields of toxicants produced: 

 “Sofas” made of upholstered cushions supported by a steel frame. The fire retardant in 

the cushion padding contains chlorine atoms. Thus this fuel would be a source of CO2, 

CO, HCN, HCl, and partially combusted organics. 

 Particleboard bookcases with a laminated vinyl finish. This fuel would be a source of 

CO2, CO, partially combusted organics, HCN and HCl. 

 Rigid PVC product sheet (window frame material). This fuel would be a source of CO2, 

CO, HCl, and partially combusted organics. 

 Electric power cable in a 3-D array of horizontal trays. This fuel would be a source of 

CO2, CO, HCl, and partially combusted organics. 

Photographs of these appear in Section II.D. 

Specimens of the principal components of each fuel were sent to an independent testing 

laboratory to characterize their chemical nature. The data were obtained by combusting small 

(ca. 10 mg) samples and measuring the combustion products. Generally single analyses were 

9
performed on three samples taken from different pieces of the combustibles. Since there was 

extensive unburned residue from the cable fires and since there was a possibility that the residue 

chemistry might differ significantly from the composition of the unburned product, three samples 

of the char from a single fire were sent to the test laboratory. They performed measurements on 

duplicate specimens from each of the three samples. The analytical chemical data are shown in 

Table 2. The elemental composition of the component materials in the fuels is shown in Table 3. 

Additional data on the heats of combustion (triplicate samples) are shown in Table 4. 

The details of the composition of the fuels and their test configurations are discussed below. The 

ignition modes and test configurations were selected to provide burning durations (under both 

well-ventilated and ventilation-limited conditions) that were long enough for accurate 

combustion product analyses. In some cases, adherence to realism was sacrificed to achieve this. 

Some of the sofas were burned in two different orientations to estimate the effect of fuel location 

on combustion product yields. 

Supplies of each of the test fuels were stored for future use in bench-scale test method 

assessment. 

10
Table 2. Elemental Analysis of Fuels 

Mass %

Sample C H N Cl Ca Pb Al Sb P Sn Ti Total ∆ * 

Particle Board, with laminate 46.89 6.70 2.68 0.26 n n n n n n n 56.53 43.4

46.56 6.68 3.35 0.24 n n n n n n n 56.83 43.147.12 6.60 2.76 0.26 n n n n n n n 56.74 43.2

 Mean value 46.86 6.66 2.93 0.25 56.70 43.3 Standard deviation 0.28 0.05 0.37 0.01 0.15 0.1Pressboard, with laminate 43.04 6.12 0.21 0.14 n n n n n n n 49.51 50.4

43.12 6.08 0.21 0.15 n n n n n n n 49.56 50.442.73 6.20 0.18 0.14 n n n n n n n 49.25 50.7

 Mean value 42.96 6.13 0.20 0.14 49.44 50.5 Standard deviation 0.21 0.06 0.02 0.01 0.17 0.1Cushion fabric 47.23 6.23 0.18 n n n n n n n n 53.64 46.3

48.12 6.10 0.19 n n n n n n n n 54.41 45.547.38 5.99 0.20 n n n n n n n n 53.57 46.4

 Mean value 47.58 6.11 0.19 53.87 46.1 Standard deviation 0.48 0.12 0.01 0.47 0.4Cushion padding 56.38 8.48 12.58 0.95 n n n n 0.20 n n 78.59 21.4

56.33 8.58 12.50 0.90 n n n n 0.15 n n 78.46 21.556.36 8.53 12.46 0.71 n n n n 0.21 n n 78.27 21.7

 Mean value 56.36 8.53 12.51 0.85 0.19 78.44 21.5 Standard deviation 0.03 0.05 0.06 0.13 0.03 0.16 0.1PVC sheet 35.98 4.64 <0.10 43.23 3.01 n n n n 0.38 5.92 93.16 6.8

35.87 4.57 <0.10 43.31 3.01 0.36 5.87 92.99 7.036.00 4.57 <0.10 43.34 3.03 0.37 5.84 93.15 6.8

 Mean value 35.95 4.59 43.29 3.02 0.37 5.88 93.10 6.9 Standard deviation 0.07 0.04 0.06 0.01 0.01 0.04 0.10 0.1

11
Mass %

Sample C H N Cl Ca Pb Al Sb P Sn Ti Total ∆ * 

Cable jacket 40.83 5.07 <0.10 26.77 10.42 < 0.05 72.67 27.3

40.94 5.20 <0.10 26.53 10.18 < 0.05 72.67 27.340.87 5.15 <0.10 26.68 10.24 < 0.05 72.70 27.3

 Mean value 40.88 5.14 26.66 10.28 < 0.05 72.68 27.3 Standard deviation 0.06 0.07 0.12 0.10 0.02 0.0Wire insulation 48.25 6.73 2.39 26.04 0.80 0.62 83.41 16.5

48.20 6.98 2.65 26.08 0.81 0.62 83.91 16.048.57 6.82 2.40 26.22 0.72 0.63 84.01 15.9

 Mean value 48.34 6.84 2.48 26.11 0.78 0.62 83.78 16.2 Standard deviation 0.20 0.13 0.15 0.09 0.04 0.00 0.32 0.3Cable filler 42.58 6.65 <0.10 n 49.23 50.7

42.42 6.84 <0.10 n 49.26 50.742.72 6.80 <0.10 n 49.52 50.4

 Mean value 42.57 6.76 49.34 50.6 Standard deviation 0.15 0.10 0.16 0.1Cable residue 18.39 2.30 0.20 22.99 43.88 56.1

25.42

19.03 2.45 0.21 27.76 49.45 50.5

28

17.91 2.47 0.14 30.00 50.52 49.4

27

 Mean value 18.44 2.41 0.18 26.96 47.95 52.0 Standard deviation 0.56 0.09 0.04 2.51 3.57 3.5

.62.87

* [1 - Σ (mass %) of listed elements] ** See following text for estimation methods 

12
Table 3. Elemental Analysis of Fuel Components 

Mass %

Sample C H N Cl Ca Pb Al Sb P Sn Ti Ash 

Wood 49.0 6.1 0.2 0.5 Paper 49.0 6.1 0.2 0.5 Urea formaldehyde 33.3 5.6 38.9 PVC 38.4 4.8 56.7 Dioctyl phthalate 73.8 9.8 Melamine 28.6 4.8 66.7 Cotton ( = cellulose) 44.5 6.2 Polyethylene terephthalate 62.5 4.2 Nylon 6,6 64 9.3 12 Nylon 6 66 10.2 11 FPU 57.6 5.6 11.2 Table 4. Heats of Combustion of Fuels 

Sample ∆Hc (MJ/kg) Mean σ

Particle Board, with laminate 18.24 18.17 18.07 18.16 0.07 Pressboard, with laminate 16.48 16.18 16.26 16.31 0.03Cushion fabric 18.17 17.96 17.94 18.02 0.10Cushion padding 26.09 26.02 26.12 26.08 0.04PVC sheet 16.67 16.48 1.27 16.47 0.17Cable jacket 18.30 18.41 18.36 18.36 0.04Wire insulation 23.39 23.33 23.45 23.39 0.06Cable filler 17.01 17.00 17.00 17.00 0.00Cable residue Did not ignite

13
1. “Sofas” 

These were made of arrays of upholstered cushions supported by a steel frame. The cushions 

consisted of a zippered fabric over a block of foam, with no interliner or other components. The 

finished cushions were each nominally 46 cm x 46 cm x 15 cm (18” x 18” x 6”). 

The fabric was described by the supplier as a cotton-polyester blend with no added fire retardant. 

We assumed that the polyester was a terephthalate, the formulation typically used in fabrics. 

These two components contain only carbon, hydrogen and oxygen, so the source of the nitrogen 

in the sample analyses (Table 2) is unknown. From the carbon fraction of the polymers and the 

sample analysis data in Table 2, we estimate that the fabric is about 82 % cotton by weight. 

The foam was described as a flexible polyurethane formulation containing melamine and a 

chlorinated phosphate ester fire retardant. Based on this information, we requested elemental 

analyses for C, H, N, P and Cl. Adding stoichiometric masses of oxygen from the phosphate and 

foam (assuming a TDI-polyol formulation) components, we were able to estimate the mass 

percentage of oxygen in the components. As can be seen from Table 1, this estimation accounts 

for the specimen mass to within ca. 3 %. The formulation of the foam is thus presumed to be 

well defined. 

We separated five of the cushions into their fabric and foam components and weighed them. The 

masses of the components and the cushions are shown in Table 5. Since the cushions appeared 

to burn evenly (i.e., the fabric was generally not burned away well before the foam was) and 

since they were virtually consumed in the tests (Section IV.A), we presumed that the elemental 

composition of the fuel was steady during the tests. 

Table 5. Mass (g) and Mass Fraction of Cushion Components 

Sample Fabric Padding Sum

1 236 (0.202) 933 (0.798) 1169 

2 237 (0.201) 944 (0.799) 1181 

3 240 (0.206) 925 (0.794) 1165 

4 239 (0.202) 942 (0.798) 1181 

5 244 (0.212) 907 (0.788) 1151 

Mean 239 (0.205) 930 (0.795) 1169 

F 3 (0.004) 12 (0.004) 

14
Given the fractions of the two components, we then estimated the cushion composition (mass 

fraction) to be: 

 C: 0.545 ± 1 % 

 H: 0.080 ± 1 % 

 N: 0.100 ± 1 % 

 Cl: 0.0068 ± 16 % 

 P: 0.0015 ± 17 % 

 O: 0.267 ± 4 % 

The fuel mass of 8-, 12-, and 14-cushion sofas was approximately 9 kg, 14 kg, and 16 kg, 

respectively. Using the heat of combustion for the components (Table 3) and the above 

component fractions, the derived value for the heat of combustion for the cushions is 24.4 MJ/kg 

± 3 %. 

The steel frame was fabricated of 4 cm (1.5 in) angle iron. A steel plate was placed on the seat 

to prevent collapse of the seat cushion. To stabilize the back cushions, a similar plate was placed 

on the back of the frame and the back was angled backwards at ca. 3 ° from the vertical. To 

prevent the back cushions from toppling (possibly off the weighing platform), they were attached 

to the frame with heavy unclad wire. 

The ignition burner was placed facing downward, centered over the center of the sofa, about 10 

cm above the top surface of the cushions. The propane flows are indicated in the description of 

the individual tests (Section IV.A). 

In all but two of the tests, the sofa was centered along the rear wall of the burn room, 

approximately 7 cm from the wall, facing the doorway. In two of the preliminary tests, the sofas 

were placed in the middle of the room facing away from the doorway. The intent had been to 

compare the burning behavior under different air flow conditions. However, the resources were 

not available to perform the fully instrumented tests needed to complete this assessment. 

The initial experiments involved a sofa consisting of a four-cushion seat and a four-cushion 

back. These did not result in flashover of the test room, except for the first such test, in which 

the paper lining of the wall covering ignited and provided the additional heat release needed for 

flashover. The results from this one test were not used further due to this mixing of fuels in an 

unknown ratio. Observations of these eight-cushion tests indicated that the center cushions were 

consumed before the end cushions were fully involved. Accordingly, one test (SW3) was 

performed with doubled seat cushions in the center and “armrest” cushions at either end. The 

space under the outer seat cushions was filled with drywall. This 12-cushion test marginally 

failed to produce flashover. The remaining tests were conducted with doubled seat cushions in 

the center, a second tier of back cushions, no armrests, and a modified test frame. The space 

under the outer seat cushions was filled with drywall. These 14-cushion arrays resulted in an 

acceptable pre-flashover burning period, flashover, and an acceptable post-flashover burning 

period before the fuel began to burn out. 

15
2. Bookcases

The dimensions of the bookcases were 1.83 m high x 0.91 m wide x 0.30 m deep (6 ft x 3 ft x 1 

ft). Each bookcase contained one fixed and one adjustable shelf (0.95 m and 0.72 m from the 

base of the bookcase, respectively). The finished board stock of the frame and the shelves was 

25.4 mm (1”) thick. The back of the bookcase was a sheet of vinyl-laminated pressboard 

approximately 5 mm in thickness. The typical mass of a bookcase was 27.5 kg. A diagonal 

length of steel angle iron was attached to the rear of the bookcases to prevent buckling and 

falling off the load cell during the test. 

With the exception of the chlorine content of the particleboard, the elemental compositions of the 

components were similar. Since the mass fraction of the back panel was small and since it 

tended to burn away extensively before the combustion of the particleboard was established, we 

assumed that the test material was essentially the laminated particleboard.

Samples of the sawdust from cutting the shelves were collected and sent for analysis for C, H, N, 

and Cl. We assumed that there was no fire retardant additive and thus looked for no additional 

elements. We assumed that the nitrogen came mainly from the urea formaldehyde binder, with a 

small contribution typical of wood. Using the measured mass fraction of nitrogen in the 

bookcase sample, we estimated that the composite is about 7 % urea formaldehyde resin by 

mass. Since chlorine was present in the elemental analysis, we assumed that the laminated finish 

was polyvinylchloride. Using the mass fraction of chlorine in the bookcase sample, we estimate 

that the composite is about 0.2 % PVC by mass. We obtained an empirical composition of wood 

from the published literature. After removing the mass fraction of the (non-combustible) ash, 

this led to an estimate of the fuel composition to be: 

 C: 0.481 ± 0.6 % 

 H: 0.062 ± 0.8 % 

 N: 0.029 ± 13 % 

 Cl: 0.0030 ± 4 % 

 O: 0.426 ± 1 % 

Given the possible variation in the elemental composition of different sources of woods, this is in 

good agreement with the analytical results from the test laboratory (Table 2). We concluded 

that there were no significant additional components in the bookcases. 

We again assumed that the atomic composition of the fuel was steady during the tests and that 

the char mass was a small fraction of the unburned fuel. We then used the elemental analysis 

results from Table 2 to compute the notional gas yields. The heat of combustion for the 

bookcase was equated to that for the particleboard (Table 4) as 18.16 MJ/kg ± 0.4 %. 

Early experiments with two bookcases side by side and the burner in between showed that the 

burner could ignite the pressboard back but not the particleboard. As a result, two bookcases 

were placed in a “V” formation (ca. 10° angle) to provide radiative enhancement and to trap the 

heat from the incipient fire. The rear edges of the bookcases were almost touching each other 

and the front edges were approximately 30 cm apart. The rear of the “V” was about 5 cm from

the rear wall of the burn room. The ignition burner was the same as that used for the cushions. 

16
It was placed facing upward approximately 30 cm under the lower shelf and 30 cm from the back 

of the “V.” These arrays resulted in a lengthy pre-flashover burning period, flashover, and an 

acceptable post-flashover burning period before the burning rate diminished. 

3. Rigid PVC sheeting

This was described by the supplier to be of a composition similar to that used for vinyl window 

framing. Each test involved a single sheet of unplasticized PVC that was 0.71 m x 1.83 m x 7.9 

mm (28” x 72 “ x 0.31”). 

 

The manufacturer provided the following approximate composition guidance: 75 % PVC resin, 

7.5 % CaCO3, 2 % Sn stabilizer, 7.5 % TiO2, 0.5 % process aid, 4 % acrylic impact modifier, 3.5 

% pigments. We thus requested analyses for C, H, Cl, Ca, Sn, and Ti. Using the empirical 

formulas for the metal salts, we estimated the mass fraction of oxygen in the specimens. As 

shown in Table 2, this estimation accounts for the specimen composition within 1 %, and we 

concluded that there were no additional components of significant contribution. 

We again assumed that the atomic composition of the fuel was steady during the tests and that 

the organic residue was a small fraction of the unburned fuel. Thus, for estimating the notional 

yields of product gases, we used the mean values of the elemental analyses as received from the 

testing laboratory, corrected for the non-volatile inorganic additives to obtain: 

 C: 0.423 ± 0.2 % 

 H: 0.0553 ± 0.9 % 

 Cl: 0.522 ± 0.2 % 

The measured heat of combustion for the PVC sheet was 16.17 kJ/kg ± 1.0 %. 

The PVC sheeting was only combusted in concert with burning bookcases. The sheet was 

supported horizontally on an angle iron frame 0.81 m (32 in.) above the floor of the front of the 

burn room. The length of the sheet was parallel to the front of the room and 0.81 m (32 in) from

it. Radiative ignition occurred as the combustion of the bookcases approached flashover. 

4. Electric power cable

This was typical of the product used for household wiring. It had two 14 gauge copper 

conductors insulated with nylon and PVC, an uninsulated ground conductor, two paper filler 

strips, and an outer jacket of plasticized PVC. 

We provided the testing laboratory with separated samples of the jacket, the wire insulation, and 

the filler material. Based on information from the manufacturer, we requested analyses for C, H, 

N, Cl (insulation and jacket only), Al and Sb (insulation only), and Ca and Pb (jacket only). We

instructed the test laboratory to cut cylindrical slices of the insulation cylinders to promote even 

sampling of the nylon and PVC components. 

To estimate the oxygen fraction of the cable jacket, we assumed that the plasticizer in the PVC 

was dioctyl phthalate (DOP), and that no additional fire retardants had been added. We 

17
estimated the PVC fraction (ca. 0.47) from the chlorine fraction in the sample (Table 2) relative 

to the Cl fraction in pure PVC (Table 3). Similarly, we estimated the CaCO3 fraction (ca. 0.26)

from the Ca fractions in the two tables. We then obtained the DOP fraction (ca. 0.27) by 

difference. From the chemical formulations of the three components and these composition 

fractions, we estimated the O mass %. As can be seen from the rightmost column of Table 2, 

there is clearly an unaccounted component in the jacket. Since the relative organic component 

fractions and the elemental composition are self-consistent, we expect that there is an additional 

inorganic filler present. 

A similar analysis was performed for the wire insulation. The PVC fraction (ca. 0.47) was 

estimated as above, the nylon fraction (ca. 0.24) was estimated from the N content, the 

aluminum trihydrate content (ca. 0.037) from the Al content, and the antimony oxide fraction 

(ca. 0.0074) from the Sb content. The DOP fraction (ca. 0.19) was obtained by making the sum

of the carbon contributions from the PVC, nylon, and DOP components equal the chemical 

analysis results. There is evidence of an unidentified component, most likely an inorganic filler. 

We did a similar analysis for the paper. Since the analyzed nitrogen fraction was very small, we 

assumed that the sample consisted only of C, H, and O. We then calculated the O fraction using 

the paper chemistry from Table 3 and the elemental analysis from Table 2. Depending on 

whether we balanced the carbon content of the filler or the hydrogen content, we obtained two 

different results, as shown in Table 2. However, since the paper constituted a small fraction of 

the total mass, this was not pursued further. 

We weighed the components of samples from five different reels of cable. Each sample was 

about 30 cm in length. The results are shown in Table 6. 

Table 6. Mass (g) and Mass Fraction of Electrical Power Cable Components 

Sample Insulation Wire Paper Jacket Sum

1 14.3 (0.518) 5.9 (0.214) 0.9 (0.033) 6.5 (0.235) 27.6 

2 14.5 (0.522) 5.9 (0.212) 0.9 (0.032) 6.5 (0.234) 27.8 

3 14.7 (0.521) 6.0 (0.213) 0.9 (0.032) 6.6 (0.234) 28.2 

4 13.8 (0.502) 5.8 (0.211) 0.9 (0.033) 7.0 (0.255) 27.5 

5 13.7 (0.517) 5.6 (0.211) 0.9 (0.034) 6.3 (0.238) 26.5 

Mean 14.2 (0.516) 5.8 (0.212) 0.9 (0.033) 6.6 (0.239) 27.5 

F 0.4 (0.007) 0.1 (0.001) 0.0 (0.0007) 0.2 (0.007) 

Combustible

Fraction 

0.655 ± 0.009 0.042 ± 0.009 0.303 ± 0.009 0.788 

Table 2 shows that the chlorine content of the char was similar to that of the unburned fuel. We

thus assumed that the elemental composition of the consumed fuel was steady during the tests. 

After removing the mass fraction of the (non-combustible) copper conductor and the inorganic 

fraction, this led to estimates of the fuel composition to be: 

18
 C: 0.576 ± 0.5 % 

 H: 0.080 ± 1.5 % 

 Cl: 0.323 ± 0.4 % 

 N: 0.021 ± 6 % 

We used these results to compute the notional gas yields. 

We assumed that the copper remained in its initial, non-oxidized state. Using the heats of 

combustion for the components (Table 4) and the above composition fractions, the derived value 

for the heat of combustion for the combustible fraction of the cable is 21.60 MJ/kg ± 0.6 %. 

To determine the size of the cable array needed to bring the burn room to flashover and to sustain 

post-flashover burning for about 3 minutes, we used data from Dey 13 on the heat release rate per 

unit surface area of a cable tray and estimated values of the heat of combustion (25 MJ/kg) and 

specific mass loss rate (3 g/m2

s). The calculation indicated that six trays, each 1.83 m by 0.31 m

in surface and containing 5 layers of cable would suffice. Thus, two cable racks containing 3 

trays each were constructed. 

The cable was cut to lengths of 1.83 m ± 0.03 m. The bottom two trays were disproportionately 

loaded since they would ignite first and should not burn out before all six trays were aflame. The 

bottom two trays held approximately 30 kg of cable each, while the middle and top trays held 

about 17 kg each. As expected, these arrays resulted in an ample pre-flashover burning period, 

flashover, and an acceptable post-flashover burning period before the burning rate diminished. 

The cable trays were placed parallel to the rear of the burn room. The rear tray was 300 mm

from the rear wall; the space between the trays was 15 cm. The burner centers were 380 mm

(1.25 ft) apart and were centered under the bottom tray of each rack.

D. Test Plan 

For each product type, a series of preliminary experiments (Table 7) was performed to: 

• Identify ignition protocols and fuel distribution to produce the desired burn period of two 

to three minutes before the combustion would become ventilation limited.

• Determine or verify the mass of fuel needed to produce flashover in the room and sustain 

it for two to three minutes. 

• Measure the rate of heat release and rate of mass loss, enabling calculation of the 

effective heat of combustion from these fuel packages. 

Tests were also conducted to ascertain any differences in the rate of heat release and combustion 

efficiency between: 

 A sofa in the rear of the burn room facing the doorway and 

 A sofa in the center of the room and facing away from the doorway. 

19
For these 11 tests, as noted in Section II.A, a panel was removed from the corridor ceiling for 

determination of the rate of heat release (Section III.A.) 

Twenty-two room-scale fire tests were performed with the ceiling hole closed (Table 7). These 

tests are categorized as follows: 

 SW1-3: Three tests with an 8- or 12-cushion sofa located against the back wall of the 

burn room, facing the open doorway. These tests did not proceed to flashover, but 

generated data for pre-flashover conditions. (Figures 6-7)

 SW10-14: Five replicate tests with a 14-cushion sofa located against the back wall of the 

burn room, facing the open doorway. The intent was to provide an estimate of test 

repeatability. (Figure 8) 

 SC1-2: Two tests with the sofa against the back wall, but with the doorway blocked, to 

determine the effect of room vitiation. 

 BW1-7: Tests of two bookcases each, arrayed in a V shape, opposite the corridor 

doorway, with the door to the corridor open. (Figure 9) 

 BP1-3: Similar bookcase tests, but with the rigid PVC sheeting product as an additional 

source of combustion products. (Figure 10) 

 PW1-2: Tests of electric cable in the tray assembly, which was located parallel to the 

back wall of the burn room, with the doorway to the corridor open. (Figure 11) 

20
Table 7. List of Room Fire Tests 

Test # Fuel Location Instruments NotSQW1 8 cushions Against rear wall None New drywall; paper burnSQW2 8 cushions Against rear wall None Did not go to flashover BQW1 2 bookcases Flat against rear wall Hood only Did not go to flashover BQW2 2 bookcases Against rear wall - V Hood only SQW3 8 cushions Against rear wall Hood only Did not go to flashover SQW4 8 cushions Against rear wall Hood only Did not go to flashover SQM1 8 cushions Mid-room Hood only Did not go to flashover SQM2 8 cushions Mid-room Hood only Did not go to flashover BQW4 2 bookcases Rear wall – V None BW1 2 bookcases Rear wall – V Hood Calcium silicate board rSW1 8 cushions Against rear wall All Did not go to flashover SW2 8 cushions Against rear wall All Did not go to flashover SW3 12 cushions Against rear wall All Did not go to flashover BW2 2 bookcases Rear wall – V All but FTIR BW3 2 bookcases Rear wall – V All but FTIR BW4 2 bookcases Rear wall – V All BW5 2 bookcases Rear wall – V All but FTIR Did not go to flashover BW6 2 bookcases Rear wall – V All but FTIR PQ1 Cable Rear wall AllPQ2 Cable Rear wall AllPW1 Cable Rear wall AllPW2 Cable Rear wall AllSW10 14 cushions Rear wall All SW11 14 cushions Rear wall All SW12 14 cushions Rear wall All 

21
Test # Fuel Location Instruments Not

SW13 14 cushions Rear wall All SW14 14 cushions Rear wall All BP1 2 bookcases/

PVC 

Bookcases: rear wall PVC sheet: room front 

All

BP2 2 bookcases/

PVC 

Bookcases: rear wall PVC sheet: room front 

All 

SC1 8 cushions Rear wall Location 1 Door closed; did not go SC2 8 cushions Rear wall Location 1 Door closed; did not go BW7 2 bookcases Rear wall All BP3 2 bookcases/

PVC 

Bookcases: rear wall PVC sheet: room front 

All

Test Title Key [X(Y)Zn] 

X: Fuel [S = sofas; B = bookcases; P = power cable] 

Y: Q = heat release rate test (ceiling hole open) Z: M = combustibles located near middle of burn room

W = combustibles located near rear wall of burn room

P = combustibles include PVC sheet 

C = doorway closed 

n: test number for that set of combustibles and location 

22
Figure 6. Photograph of 8-cushion Sofa 

Figure 7. Photograph of 12-cushion Sofa 

23
Figure 8. Photograph of 14-cushion Sofa 

Figure 9. Photo of V-oriented Bookcases in the Burn Room 

24
Figure 10. Photograph of Bookcases and PVC Sheet in the Burn Room 

Figure 11. Photograph of Cable Trays in the Burn Room 

25
E. Measurements and Sampling Methods 

Calculating the rate of heat release requires certain measurements in the exhaust duct: oxygen 

concentration, mass flow of the effluent stream, and temperature of the stream. 

Determining the yields of the toxic gases requires both measurement of the concentrations of 

those gases and the other time varying factors that enable conversion of the concentrations into 

species yields: 

 Mass flow through the doorway, which is a function of the door area through which the 

flow exits the burn room, the temperature and density of that flow, and the pressure 

differential across the doorway. 

 Mass loss of each combustible. 

The instrumentation and methods used to measure each of these quantities are discussed below. 

Readers interested in a general overview of large-scale fire testing data collection and analyses 

are referred to Peacock and Babrauskas.14

1. Exhaust Duct Quantities 

Instrumentation in the 6 m square hood10 was used to obtain input data for calculation of the rate 

of heat release of the burning combustibles. Concentrations of oxygen, carbon dioxide and 

carbon monoxide were made at a single point in the centerline of the exhaust stack. Temperature 

and pressure were measured at six positions and averaged to obtain single values for the 

calculation of the mass flow. 

2. Temperature 

Knowing the vertical temperature profile is central to: 

 Defining the fraction of the doorway opening through which combustion products exited 

the burn room, 

 Quantifying the exit flow from the burn room, and 

 Characterizing the smoke flow down the corridor. 

As part of the characterization of the flow through the doorway, a thermocouple tree was located 

in the doorway, approximately 100 mm (4 in) from the door edge. The 10 individual 

thermocouples were placed at heights of 0.53 m, 0.68 m, 0.83 m, 0.98 m, 1.13 m, 1.28 m, 1.43 

m, 1.58 m, 1.73 m, and 1.88 m from the floor. The 10 thermocouples were an aspirated design 

characterized by Pitts et al.

15 and based on a design by Newman and Croce16. The shield had a 

diameter of 6.3 mm. The shield housed a type K chromel-alumel thermocouple constructed from

0.51 mm diameter wire. A flow of 18.9 L/min (at ambient temperature) was drawn through each 

aspirated thermocouple by a dedicated pump. The aspirated gases were filtered and dried before 

passing through the pumps. 

26
Three additional trees of 12 bare-bead thermocouples were used to determine the vertical 

temperature stratification in other locations: 

 in the burn room approximately 1 m from the doorway wall and 1 m from the adjacent 

side wall, and 

 in the corridor 1 m from the room of fire origin and 1 m from the adjacent side wall. 

These type K thermocouples, constructed from 0.25 mm diameter wire, were spaced evenly from 

floor to ceiling at 150 mm ± 10 mm (6 in ± 0.4 in) intervals, again, beginning 0.53 m from the 

floor. 

A single type K thermocouple was located just below the centerline of the doorway lintel. This 

was used during the tests to assist in anticipating the onset of flashover. 

In a past series of well-controlled gas burner tests17, the standard uncertainty for peak gas 

temperature had been found to be ± 16 °C. This is expressed as the standard deviation of the 

peak values for 12 replicate tests. While random variation in the current experiments is expected 

to be comparable to these values, additional uncertainty due to variation in the ignition and fire 

growth of the fire sources from this test series can be expected. Replicate tests were conducted 

here to bound the uncertainty under the conditions of these tests. 

3. Doorway Velocity

The other component of doorway velocity measurement was a vertical array of 10 bi-directional 

velocity probes designed for measuring the soot-laden doorway flows. These were based on a 

design developed by Heskestad (Figure 12).18 Differential pressure from the two sides of the 

probes allows direct calculation of velocity and vent flow.19 For the experiments in this report, 

vertical arrays of 10 bi-directional velocity probes and 10 corresponding aspirated thermocouples 

provide data for the calculation of vent outflow. Standard uncertainty in vent flow 

measurements has been reported to be approximately ± 10 %.19 Replicate tests in the current 

series served to bound the uncertainty under the conditions of these tests. 

4. Sample Delay Times 

Delay times for gas flows from sampling locations within the test structure to the NDIR and 

FTIR gas analyzers were determined by introducing a pulse of gas into the sampling lines and 

measuring the time for each instrument to respond. Since the NDIR line temperatures were close 

to ambient during the tests and the FTIR lines were heated during these determinations, the 

values in Table 8 are very close to those experienced during the tests. Calculations for several of 

the experiments with changes in the delays ranging from 10 s to 40 s show less than 1 % change 

in calculated species yields. 

27
Table 8. Instrument Delay Times and Standard Deviations (s) 

Sampling Location 

Analyzer 1 2 3 4

CO2, CO, O2 20 ± 2 34 ± 3 21 ± 1 9 ± 1 

FTIR 3.0 ± 0.5 2.5 ± 0.5 -- 3.0 ± 0.5 

Figure 12. Schematic of Bi-directional Velocity Probes 

Support tubes

(Connect pressure taps to

indicating instrument)

D = arbitrary typ.

15-25 mm

0.286D

0.572D

0.857D D

2D

5. Sample Mass 

During each test, the mass of the test combustible was recorded using one of two load cells. 

 One with top surface measuring 1.5 m by 2.4 m (5 ft by 8 ft) was used to measure the 

mass loss of the initially ignited item (sofa, bookcases or cable trays). This load cell has 

a capacity of 1000 kg (2200 lb) with a rated resolution of 0.5 kg (1.1 lb). 

 A second was used to measure the mass loss of the PVC sheet when it was used as a 

target object. The top surface of this load cell measured 0.6 m by 0.8 m (1.5 ft by 2.5 ft) 

and had a capacity of 150 kg (300 lb) with a resolution of 2 g (0.004 lb). 

28
6. CO, CO2, and O2 Concentrations 

As presented in Section II.B.3, samples for analysis of these gases were extracted from four 

locations. In the case of the four-probe arrays, this probe was the downstream (D) tube. Each 

probe was constructed of stainless steel tubing 12.7 mm (0.5 in) in outer diameter. The probes at 

the three corridor locations were inserted horizontally through the corridor sidewall and were 

thus roughly isothermally heated along their length to the layer height temperature at the time. 

The probe into the burn room was inserted through the ceiling. The sampling tips of the 

sampling probes were simply the blunt ends of the tubing. On the outside of the burn room or 

corridor wall, each probe D was connected to a length of unheated copper tubing 6.2 mm in outer 

diameter. Approximately 5 m downstream, this tubing was formed into a helical coil, which was 

immersed in an ice bath and then a dry ice bath to trap water vapor, aerosols and soot. A length 

of plastic tubing continued to the analyzers. A pump located on the downstream end of the train 

drew sample at an estimated rate of 10 L/min. 

CO and CO2 concentrations were measured continuously using nondispersive infrared (NDIR) 

analyzers. These instruments utilize absorption of infrared light at a single wavelength whose 

selection discriminates against absorption by strongly absorbing interferants such as water. 

None of the gases known to interfere with NDIR measurement of CO2 and CO were expected to 

be present in sufficient quantity in these experiments to warrant correction to the absorption data. 

See Link et al.20 for further details of the NDIR technique. 

Oxygen measurements were made using paramagnetic analyzers. None of the other combustion 

gases known to have significant paramagnetic moments were expected to be present in sufficient 

quantity in these experiments to warrant correction to the data. 

Prior to each test, flows of gas mixtures of known concentration insured correct operation of the 

analyzers and enabled any corrections to manufacturer-supplied calibration curves. Typically, 

these corrections were less than 1 % of the measured value.

For a series of well-controlled gas burner tests17, the standard uncertainties for oxygen, carbon 

dioxide, and carbon monoxide concentrations were found to be ± 0.6 %, ± 0.4 %, and ± 0.06 %, 

respectively. These are expressed as the standard deviation of the peak values for 12 replicate 

tests. The random variations in the current experiments are expected to be comparable to these 

values. Additional variation (in these and all measurements) arising from variations in the 

ignition and growth rate of the fire are estimated in Section IV.F from the results of replicate 

tests. 

 

7. Gas Sampling for FTIR and Ion Chromatographic Analyses 

Samples for these analyses were extracted continuously at locations 2 and 4 (Section II.B.3). 

The sampling probes were the upstream (U) tubes in the four-probe arrays and were constructed 

of stainless steel tubing 12.7 mm (0.5 in) in outer diameter. At the outside of the corridor wall, 

each probe was connected to two polytetrafluoroethylene (PTFE) transfer lines 12.7 mm in outer 

diameter. 

29
From each of the two probes, one line, ca. 8 m in length, went directly to one of two Fourier 

transform infrared (FTIR) spectrometers. These lines were heated to 170 °C tests to prevent the 

condensation of water, soot, and other nonvolatiles. There were no soot filters in the transfer 

lines since these also collect acid gases. While the acid gases can be extracted and analyzed after 

the test is over, one only obtains an integrated mass of each compound, and meeting the 

objective of this study requires time-resolved (at least pre- vs. post-flashover) concentration 

information. 

The second lines, also ca. 8 m in length but unheated, were for transport of the gases for wet 

chemical analysis. Unlike the sampling for essentially continuous FTIR analysis, the ion 

chromatographic technique utilized batch samples, i.e., samples accumulated over some time

interval. Two samples were collected at each location in each experiment: one during the preflashover phase and one post-flashover. 

The collection intervals differed with each experiment and were determined by the test

coordinator. When the test coordinator determined that it was appropriate to begin sampling preflashover smoke, a valve was opened diverting the extracted flow from the heated PTFE tubing 

to, in order: 

 a 250 mL glass impinger bottle containing 125 mL of 5 mM KOH in water conditioned to 

18.2 MΩ –cm (ultra-low electrical conductivity); 

 a 45 mm diameter PTFE filter (0.45 μm nominal porosity) to break up the gaseous 

aerosol and allow maximum collection in the first impinger. 

 a 125 mL glass impinger bottle containing 100 ml of 5 mM KOH, also in water 

conditioned to 18.2 MΩ –cm;

 a Matheson 602 rotameter equipped with a control valve; and 

 a pump. 

At the end of the pre-flashover period, the flow was diverted to an exhaust line. When the test 

coordinator determined that it was appropriate to begin sampling post-flashover smoke, the flow 

was directed to a second identical set of impingers. At the end of this second collection period, 

the flow was again diverted to the exhaust line. 

The flows through both analysis trains were measured prior to each test with an American Meter 

Company DTM-115 dry test meter. The flows to the FTIR spectrometers were maintained at 10 

L/min ± 0.5 L/min using Matheson 602 rotameters with control valves. The flows to the 

impingers were similarly maintained at 1.00 L/min ± 0.055 L/min. 

During the two closed room tests, the transfer lines from the probe at the downstream end of the 

corridor were moved to another probe located on the burn room centerline approximately 1 m

inside the burn room door.

30
As with the fixed gas analyzers, the signal delay resulting from the combination of residence 

time in the sampling line and the FTIR spectrometer response time was determined using gas 

pulses introduced at each probe tip. The time delays were 2.5 s ± 0.5 s for the upstream 

measurements and 3.0 s ± 0.5 s for the downstream measurements. 

8. FTIR Analysis 

The infrared absorbance spectra of fire gases extracted from two locations inside of the test 

facility were measured simultaneously at a frequency resolution of 0.5 cm-1. Photographs of the 

FTIR spectrometers used in making these measurements are shown in Figure 13. Both are Midac 

Illuminator spectrometers equipped with mercury cadmium telluride (MCT) detectors. The unit 

used to monitor the fire gases at location 2 is configured with a closed optical path through an 

internal (stainless steel) cell fitted with ZnSe windows. The other spectrometer, which was used 

predominately at location 4, but was moved to location 1 for two tests, is an open path unit 

consisting of separate source and detector modules. An external monel cell with KBr windows 

was positioned in the optical path between the two modules. Although both cells were nominally 

10 cm long, their optical pathlengths, which were determined by fitting the measured spectrum

of CO at a known concentration (216 μL/L) to calibration spectra, were significantly different. 

The pathlength of the stainless steel cell with ZnSe windows was found to be 8.2 cm, while the 

monel cell with KBr windows was 11.5 cm. The scanning rate of both spectrometers at 0.5 cm1 

resolution is approximately 1.5 spectra/s. The spectrometer at location 2 was programmed to 

signal- average over 2 spectra, whereas the spectrometer at location 4 was configured to signal 

average over 4 spectra. Therefore, the concentrations of the target compounds at locations 2 and 

4 were updated every 1.3 and 2.7 seconds, respectively. 

Figure 13. Photograph of the FTIR Spectrometers 

In selecting cell sizes for these spectrometers, there were two conflicting considerations. A 

larger cell with a multi-pass optical path (ca. 1 m) offers higher sensitivity, a benefit when 

examining trace compounds, but a potential saturation problem with the major species. A 

smaller cell with a smaller volume offers better time resolution, an important issue when the 

31
combustion conditions in the fire are likely to be changing during a test. We deemed the latter 

consideration to be more important and used the smaller optical cells. 

A typical spectrum measured by FTIR spectroscopy during the fire tests is displayed in Figure 

14. The series of peaks extending from about 3050 cm-1 to 2600 cm-1 are due to HCl. In this 

case, it is possible to resolve the individual frequencies corresponding to changes in the 

population of rotational states as the H-Cl bonds vibrate. This is usually only possible for small 

gas phase molecules. There are three spectral features due to CO2 that are evident in this 

spectrum. The most intense, centered at 2350 cm-1, corresponds to asymmetric stretching of the 

two C=O bonds. The symmetric stretch is not observed because there is no change in dipole 

moment when both O atoms move in phase. The second feature, seen as two distinct peaks 

centered at about 3650 cm-1, is an overtone band that derives from the simultaneous excitation of 

these bond-stretching modes. The third peak at about 650 cm-1, only partially visible in Figure 

14, is due to the out of plane bending of the molecule. Also shown are the bands due to the C≡O 

and H-CN stretching vibrations of CO and HCN centered at about 2150 cm1 and 3250 cm-1, 

respectively. The latter band interferes strongly with the C-H stretching vibration of acetylene, 

which is also present in the fire atmospheres. The remaining peaks in this spectrum are due to 

H2O. 

As noted earlier, the toxicants under investigation were: CO2, CO, HCN, HCl, HF, HBr, NO, 

NO2, and CH2=CH-CH=O (acrolein). The relative concentrations of these compounds were 

determined from IR absorbance measurements of the fire gases using Autoquant 3.11. This is a 

software package for performing real time quantitative analyses of target compounds, which is 

based on the Classical Least Squares (CLS) algorithm as described by Haaland et al.

21 In this 

method, the measured spectra are fit to linear combinations of reference spectra corresponding to 

the target compounds.

The implementation of this method requires that the user supply calibration spectra 

corresponding to the IR absorbencies of known concentrations of the target compounds. These 

data were obtained from a quantitative spectral library assembled by Midac22 and from a 

collection of spectra provided by Federal Aviation Administration staff who had performed 

bench-scale fire tests on similar materials.23 In our implementation, the least squares fits were 

restricted to characteristic frequency regions or windows that were selected in such a way as to 

maximize the discrimination of the compounds of interest from other components present in fire 

atmospheres. For some of the gases, a piece-wise concentration interpolation (PWCI) was 

employed to correct for deviations from the linear dependence of absorbance on concentration. 

This procedure, which requires spectra of the calibration gases at multiple concentrations, 

involves interpolating between independent CLS analyses such that the predicted concentrations 

fall between the concentrations of the calibration mixtures.24

The identities of the target compounds (as well as other compounds that absorb at the same

frequencies and must, therefore, be included in the analyses), their corresponding concentrations 

(expressed in units of ppm for a mixture of the calibration gas and N2 in a 1 meter cell), and the 

characteristic spectral windows used in the quantitative analyses are listed in Table 9. 

 

32
Figure 14. Representative Spectrum of the Fire Gases Extracted during a Test 

Also listed in this Table are minimum detection limits (MDLs) for each of the target compounds. 

These values, which represent the lowest concentrations that can be measured with the 

instrumentation employed in these tests, were estimated as follows. The calibration spectra were 

added to test spectra (which, when possible, were selected in such a way that only the compound 

of interest was not present) with varying coefficients until the characteristic peaks of the target 

compounds were just discernible above the baseline noise. The value of signal averaging over 

ca. 100 spectra was included. The MDL values reported in Table 9 were obtained by 

multiplying these coefficients by the known concentrations of the target compound in the 

calibration mixtures. 

Water, methane and acetylene are included in the quantitative analyses because they have 

spectral features that interfere with the target compounds. The nitrogen oxides absorb in the 

middle of the water band that extends from about 1200 cm-1-2050 cm-1. Consequently, the limits 

of detection for these compounds are an order of magnitude higher than for any of the other 

target compounds. Thus, it is not surprising that their presence was never detected in any of the 

tests. 

33
Table 9. Calibration Spectra for FTIR Spectroscopy

Compound 

Concentration 

(vol. fraction-m 

 x 106) 

Temperature (K)

(P = 101.3 kPa) 

Frequency 

Windows

(cm-1) 

Minimum 

Detection Limit 

(vol. fraction 

x 106

) 

C2H2 39 170 3190-3420 -

C3H4O 225 100 850-1200

2600-2900 

10 

CH4 48, 422 170 2800-3215 

COH2 100 2725-3000 50

CO 51, 241, 1460, 

8977, 17650 

170 10

CO2 4785, 9125, 

16329 

170 715-724

2250-2400 

5 

H2O 10000 170 1225-2150

3400-4000 

- 

HBr 226 170 2400-2800 50

HCN 51, 115 170 710-722

3200-3310 

15 

HCl 987 170 2600-3100 15

HF 2025 170 4000-4150 5

NO 512 121 1870-1950 500

NO2 77 121 1550-1620 100

2010-2250

9. Acid Gas Analysis by Ion Chromatography

After the samples were collected, the contents of each impinger bottle was transferred to a tared 

plastic bottle and weighed. The PTFE filters were removed from their holders and placed in the 

plastic bottle containing the contents from the first impinger. Approximately 3 mL aliquots were 

removed from each plastic bottle and filtered through an 0.45 μm filter (to remove any 

particulate matter) into an ion chromatography vial for analysis. 

A Dionex DX600 ion chromatograph equipped with a GP50 gradient pump and a CD25 

conductivity detector and IonPac AS11 column was used to analyze for Cl ̄, Br ̄, NO2 ̄, and 

NO3 ̄. The instrument was calibrated as follows: 

1. Stock solutions of Cl ̄, Br ̄, NO2 ̄, and NO3 ̄, nominally 1000 mg/L each, were prepared 

by dissolving the appropriate amount of salt in 18.2 MΩ-cm water. 

34
2. Using serial dilutions of these solutions, curves of anion peak height vs. anion 

concentration were determined. 

3. A calibration function was derived from these data. Least squares analysis of the 

resulting lines indicated a high degree of linearity (r2

 = 0.9915) over the anion 

concentration range1.0 mg/L to 5.0 mg/L.

Comparisons of the values with the corresponding results obtained from the FTIR analyses 

indicated that the wet chemical method gave far lower yields (by more than an order of 

magnitude) of HCl and HCN. Experiments performed at the conclusion of the test matrix 

revealed that significant amounts of impinger water were being drawn through the unheated lines 

connected to the impinger bottles during the tests. Based on this observation, we have concluded 

that most of the gases of interest must have dissolved in this water, which presumably clung to 

the walls of the PTFE lines in form of droplets and was, therefore, never accounted for in the wet 

chemical analyses. Thus, no further discussion of these results is included in this report.

10. Smoke Mass 

Of interest to this project is the extent to which reactive gases diminish in concentration as they 

travel from the fire vicinity. One mechanism for the loss of these gases is by adsorption on 

particulate matter. Accordingly, the concentration of smoke was determined at locations 2 and 4 

in the corridor where the reactive gas concentrations were also measured.

As with the impinger bottle samples, two samples were collected at each location in each 

experiment: one during the pre-flashover phase (Probe T) and one post-flashover (Probe B). The 

specific sampling time intervals were nominally the same as for the impinger bottle sampling. 

At the outside of the corridor wall, each probe passed through a 42 cm long water jacket heated 

to 55 °C to prevent the condensation of water and other volatiles. The smoke was collected on a 

polytetrafluoroethylene (PTFE) filter with a 2 μm pore size housed in a stainless steel filter 

holder also heated to 55 °C. The collection efficiency for this filter was at least 96 % for particle 

sizes of 0.035 μm and larger. This size range includes essentially all the smoke particles. The 

flow through the filter was 50 cm3

/s (3 L/min). 

Because a significant mass of sampled smoke might collect on the interior wall of the sampling 

line (before reaching the filter), a cotton pad was used to clean the inside of the tube in a manner 

similar to cleaning a gun barrel. The fraction of smoke deposited in the tube varied from about 

15 % for the bookcase fires to as large as 75 % for the tests involving bookcases plus a PVC 

sheet. Even with this cleaning procedure, some of the smoke was retained on the tube walls; this 

was estimated to be no more than 15 % of the total. 

Repeat weighings of the collected smoke were made after storing the filters overnight to assess 

the impact of condensables. The change in mass was typically less than 2 %. The moisture 

effect is typically small for PTFE filters; however, it can be a substantial effect for quartz or

fiberglass filters. The typical uncertainty in the filter weighing was about 0.05 mg for a 1 mg

filter weight. The filter weights ranged from 0.4 mg to 40 mg. The mass concentration of smoke 

corrected to 101 kPa and 25 °C ranged from 0.2 g/m3

 to 20 g/m3. 

35
11. Heat flux 

As one measure of whether and when flashover was achieved in the burn room, the radiant flux 

at the floor in the burn room enclosure was measured using a Medtherm 20 W/cm2

 Gardon-type 

total heat flux gauge. The manufacturer’s specified accuracy was ± 3 % with a repeatability of ±

0.5 %. The gauge was positioned looking upward, with its measuring surface flush with the 

floor surface of the burn room, centered between the two side walls at approximately 1 m (3.3 in) 

from the doorway. 

12. Video 

The progress of most tests was monitored using two Super 8 video cameras. One was located 

beyond the open end of the corridor and viewed the full length of the corridor and the interior of 

the burn room. The second was located in the forward lower corner of the burn room and was 

directed upward toward the burning fuel. For the two tests where the sofas were located in the 

burn room center facing toward the rear, this camera was relocated to the lower rear corner. 

Only one camera was active during the tests with the burn room door closed. This was located in 

the lower front corner of the burn room as above. 

 

13. Additional Data 

The building temperature, pressure and relative humidity were recorded at the beginning of each 

test. 

F. Data Collection 

1. Hardware 

The signals from the various measurement devices (except the FTIR spectrometers) were 

collected using the NIST Large Fire Facility data acquisition system (DAQ). The DAQ is 

currently configured to collect data both from instruments in the exhaust duct of the 6 m hood for 

calorimetry calculations and from any other instruments or sensors located in the vicinity of the 

experiment. 

The hardware consists of National Instruments components. The primary DAQ board is unit 

PCI6052E, which has a PCI bus computer interface, 16 analog channels, 16 bit resolution, 333 

ksamples/s sampling rate, eight digital I/O channels, and two 24-bit counter/timers. An 

SCXI1001 chassis box holds seven modules for multiplexing channels onto one DAQ board 

channel. The SCXI1102B module was the primary component used for multiplexing and signal 

conditioning. Each module has 32 channels capacity, a 200 Hz low pass filter, and 100X gain 

option for low voltage signals. Each module was connected to a TC2095 shielded terminal 

block, which collects signals of up to 10 V amplitude and provides cold junction compensation 

for any thermocouples voltages. 

36
A total of 130 channels were scanned for these experiments; 40 were inputs to the calorimetry 

calculations, and the remaining 90 were unique to this series of experiments. While the DAQ 

has the capability to scan each channel 300 times per second, the typical rate in these tests was 

200 scans/s. The 200 values for each channel were averaged for an overall output and storage 

rate of 1 sample/s. In addition, during each 1 s cycle or loop, numerous calculations were 

performed “on the fly” and the output stored in a second data file. 

2. Event Marking 

Three channel markers were used to keep track of specific events during a fire test: 

 Event Marker 1 was used to log the times for igniting and extinguishing the pilot burner 

and extinguishing the fire at the end of the test. 

 Event Marker 2 was used to log the times for initiating and ending the pre-flashover 

sampling period. 

 Event Marker 3 was used to log the times for the occurrence of flashover and the 

beginning and ending of the post-flashover sampling period. 

Event marking put simulated voltage spikes from 0 to 5, 10 to 15, or 20 to 25 for one second in 

the channels set up for the markers. Plotting the data in these channels along with, e.g., 

concentration and mass loss data enabled relating the evolving combustion product chemistry to 

the changing fire phenomenology in the test. 

3. On-the-fly conversions 

All data were stored as voltage magnitudes without modification in a “raw” data file. The 

exception was that all temperature measurements were converted in real time to degrees Celsius 

and stored as such. A second file was created simultaneously. For this file, all the other signals 

were converted in real time to the physical quantities they represented: CO, CO2, and O2 dry 

volume fractions, pressures, heat fluxes, smoke attenuations, and load cell masses. These were 

in turn combined to also generate flow velocities, duct volume flow, duct mass flow, and heat 

release rate. Up to 6 levels or steps of conversion and combination were used to complete all the 

calculations. For heat release calorimetry testing, data were combined after estimating the 

relative delays for each instrument and synchronizing the data generated by a given moment of 

the fire. For the remainder of the tests, no delays were implemented and the relative time

responses of the measurements were post-processed. 

4. Real time presentation 

Prior to this research project, all channels of data were available digitally in either raw or 

converted form, and two channels could be user-selected for graphical display. Also, calorimetry 

analyzer readings, velocities, and heat release rate were displayed graphically with up to 6 min of 

history. 

For this project, several measurements were deemed important for periodic monitoring during 

each test and thus additional graphical presentations were created. These graphs were: all CO, 

CO2, and O2 volume fractions from the NDIR and paramagnetic analyzers, the temperatures 

37
from the thermocouple tree in the fire room, the doorway temperatures from the aspirated 

thermocouples, the velocities in the doorway, and the four temperatures from the soot probes. 

The fire room temperature graph could at any time be changed to plot any group of 12 adjacent 

channels. 

5. Storage for analysis 

Each scan and calculation loop included a file writing procedure as well. Three files were 

generated during a test with suffixes “raw,” “adj,” and “ZS:” 

 The “raw” file recorded raw voltage values only, plus the addition of the 3 marker 

channel values. 

 The “adj” file recorded real channels with their simple one-step conversions applied and 

all of the artificial channels that combined real channels in one or more steps. Also, if the 

user specified, the “adj” file listed results of calculations that were combined so as to 

synchronize the inputs to the same event. Thus, in such a time-adjusted “adj” file, e.g., a 

burst of flame in the fire room would line up in time with all the following: the increase 

in specimen mass loss, an increase in temperature 20 m down the duct, and the 

corresponding increase in CO2 sampled 20 m down the duct and then transported 30 m 

into the analyzer with its own inherent processing delay. 

 The third file, with the suffix “ZS,” listed the voltages generated by the zeroing and 

spanning processes for the gas analyzers as well as the calibration signals for the response 

of pressure transducers, load cells, etc. The former set are linear and interpolation 

between the two calibration points enables assignment of concentrations to the recorded 

voltages. The instruments in the latter group are generally non-linear or nearly linear, 

and these have been pre-calibrated over the necessary range. These calibration equations 

require a single point each to enable conversions from voltage to, e.g., Pa or kg. 

G. Test Procedure 

There were a number of steps taken before the ignition of the test specimen: 

 Setting the test specimen in place and recording its precise location and orientation; 

 Describing the test specimen (e.g., the number of cushions in a sofa, their relative 

positions, the wiring of the vertical cushions to the metal frame, recording the mass of the 

specimen); 

 Ensuring the ignition device was properly placed; 

 Inspecting the following for test readiness: 

 back-up suppression capability (standpipe and fire hose), 

 firefighters in turn-out gear, 

 gas racks zeroed and spanned, 

 video cameras running, 

38
 cold traps filled with ice/dry ice, 

 gas rack identification numbers recorded, 

 aspirated thermocouples running, 

 pumps operational for smoke collection lines and wet chemistry sampling lines, 

 FTIR spectrometers calibrated, 

 test and DAQ clocks synchronized 

 bi-directional probes operational, 

 heat flux gauge cleaned, 

 and “flashover indicator” (balled-up piece of newspaper) placed on the floor of the 

burn room in view of the water-cooled camera, 

 ambient pressure, temperature, and humidity recorded. 

Next, two minutes of “background” values were recorded for all instruments. This was followed 

by a 10 s countdown to ignition during which all of the separate apparatus functions (data 

acquisition system, FTIR spectrometers, wet chemistry sampling, and smoke sampling) were 

further synchronized. 

A firefighter, located in the burn room, ignited a portable gas torch. The propane flow to the 

ignition burner(s) was initiated, and the firefighter lit the burner. This time was recorded. 

 

For the sofa and cable tray fires, the burner was kept lit until the test manager determined that the 

test specimen was ignited. This was defined as sustained flaming over a volume distinctly 

greater than that of the burner and was followed by direct observation through the doorway and 

by monitoring the output of the in-room video camera. The burner was then turned off and the 

firefighter withdrew, removing the burner from the burn room in the case of the sofa fires. [The 

sand burners used in the cable tray fires were not removable.] Both the times of ignition and the 

time of burner extinguishment were recorded. 

For the sofa fires with the room doorway closed, the test manager followed the ignition process 

from the in-room video output. The electric match was not moved following ignition. 

For the bookcases, it was difficult to determine when the particleboard was able to sustain 

burning. Following an apparent ignition, the flames would occasionally recede. In those cases, 

the burner was again ignited until significant flaming was observed, at which point the burner 

was extinguished. The time of assured ignition was recorded. 

When the fire effluent was actively flowing out of the room of origin, sampling of the preflashover smoke to the various instruments was initiated and the time recorded. The target time 

interval for pre-flashover measurements was three minutes, although this time was frequently 

shortened when the test manager estimated that flashover was imminent. The time at which preflashover analysis stopped was recorded. 

39
The time of flashover was recorded when the test manager observed flames extending from the 

room of origin into the hallway. This observation generally coincided with flaming of the paper 

placed on the floor in the room of origin. [Occasionally, incoming air from the hallway to the 

lower layer of the burn room blew the paper to a location where it did not see the high radiant 

flux from the upper layer.] 

Post-flashover measurements were initiated shortly after flashover. Again, the desired 

measurement period was 3 minutes, although some tests became fuel-limited and reverted to preflashover burning conditions, necessitating early measurement termination. Both the start and 

end of this period were recorded. 

At this point, one or more firefighters proceeded to extinguish the fire. For low level flaming, a 

hand-held fire extinguisher could be used. More often, the firefighter applied a stream of water 

from a garden hose. For large fires, they could have used a 11⁄2” standard hose line water stream, 

but this was not necessary in these experiments. The times at which fire suppression started and 

the time at which the flames were quenched were recorded. 

The closed-door tests self-extinguished, presumably due to a lack of oxygen. Once the test 

measurements were completed, the firefighters opened the door, which led to reignition. The 

small fire was then suppressed with a hand-held fire extinguisher. 

40
III. CALCULATION METHODS 

The following nomenclature is used in this section: 

A Cross sectional area of the exhaust duct (m2

) 

C Orifice plate coefficient (kg1/2 m1/2 K1/2) 

E Net heat release per unit mass of oxygen consumed (kJ kg-1) 

F Carbon mass fraction in the fuel 

m& Mass flow for gases or mass loss rate for combustible material (kg s-1) 

M Molecular weight (kg kmol-1) 

p Pressure (Pa)

q& Heat release rate (kW)

T Temperature (K) 

W Vent width (m) 

X volume fraction (dimensionless) 

y species yield (dimensionless) 

α Combustion expansion factor (dimensionless) 

∆φ volume fraction 

ε combustion efficiency 

ρ gas density (kg m-3) 

φ Oxygen depletion factor (dimensionless); see below for definition. 

Superscripts 

A refers to concentrations in the analyzer 

0 refers to initial conditions for incoming duct gases 

Subscripts

N neutral plane 

amb ambient air 

dry Dry air 

duct incoming duct gases 

f Fire 

g refers to a specific gas of interest, e.g., CO, CO2

 not refers to the notional yield of a combustion product 

 s smoke 

 t top of the vent, total 

 v vent 

41
A. Heat Release Rate 

The peak rate at which a product generates heat is the most fundamental fire property for use in 

fire hazard analysis. As such, the following text documents how the values were calculated for 

the “Q” tests, i.e., those in which the ceiling hole was open. The results were not used in 

calculating the yield information that is the primary focus of this project. 

The rates of heat release were calculated using the oxygen consumption principle, i.e., the heat 

released during complete combustion of a specimen is 420 kJ per mole of O2 consumed, with 

only a "5 % dependence on the material(s) combusted.25 This changes only slightly for the 

degree of incompleteness of combustion experienced in fire tests.26 If all of the fuel carbon were 

to be partially combusted to CO rather than fully combusted to CO2, the constant is reduced by 

about 22 %. The generation of carbonaceous material (soot) acts in the opposite direction, with a 

10 volume % generation of carbon increasing the constant by less than 3 %. In this series of 

tests, the [CO]/[CO2] ratio did not exceed 0.1 and the soot fraction was of the order of 1 % to 10 

%. Thus, we corrected for the actual CO fraction and neglected the effect of the formation of 

soot and other products of incomplete combustion. 

Since in each of the “Q” tests, all the effluent from the fire was collected in the exhaust hood, the 

total rate of heat release from the room can be determined using Janssens’ formulation:27

( ) ( ) 0

2 2

2

2

0 1

2

1 A

duct H O O

duct

O

A

O

A

CO

CO m X X

M

M

X

X

q E E E − 













 − & = − − & φ φ

where: 

(1 )( 4 2.5)4 18 2 2 2 M e = − X H O X O + X CO + +

e e

dry

e M T

M p

m C

∆ & =

( )( )

( )( ) 















− − −

− − − − = 0

2

0

2 2

2 2 2

1 1

1 1

0 A

CO

A

H O O

A

CO

A

CO

A

H O O

e

e

duct

duct

X X X

X X X X

M

m

M

m& &

( ) ( )

( ) A

CO

A

CO

A

O

A

O

A

CO

A

O

A

CO

A

CO

A

O

X X X X

X X X X X

− − −

− − − − =

2 2

0

2

0

2 2 2

0

2

1

1 1

φ

Simplifications are available, with some loss of precision, if concentrations of some of the gas 

species are not measured. For instance, the concentration of water vapor in the exhaust duct flow 

was not measured and was assumed to be the same as that measured in the ambient air due to the 

high ambient air dilution of the room effluent in the exhaust duct. 

The overall uncertainty in peak heat release determinations results from uncertainties in the 

measured terms in the above equations and from variability in the fires themselves. The former 

can be high, especially for smaller fires due to the small difference between concentrations of 

42
oxygen in the ambient air and the combustion-vitiated air. In one study28, coefficients of

variation ranged from 4 % to 52 % for a wide range of experiments. The worst case resulted 

from an oxygen depletion of only 0.26 % in a 100 kW fire. Since the peak rates of heat release 

in the current series of tests are in the range of 1 MW, we estimated that the uncertainty in the 

peak rate of heat release was about "10 %, including the aforementioned uncertainty in the value 

of E. 

The overall uncertainty is typically estimated from replicate tests, such as were performed here 

for the sofas. The repeatability of yCO2 was " 23 %. Most of the carbon was fully oxidized to 

CO2 and the heat release per mole of oxygen consumed is not very sensitive to the degree of 

completeness of combustion. Thus, this is a fair indicator of the overall uncertainty. This is 

consistent with a prior study, in which Babrauskas29 found the precision for the peak rate of heat 

release from upholstered furniture fires, both in the open and enclosed in a room, to be within 15 

% for fires of 2.5 MW. 

B. Mass Loss Rate 

The mass loss rates were determined from the slopes of the plots of mass vs. time. The noise in 

the instantaneous measurements was reduced using a running seven- point linear regression of 

the mass loss data. The slope at the midpoint of the seven-point interval was taken to be the 

mass loss rate at the midpoint. The measurement uncertainty is derived from the linearity and 

sensitivity limit of the load cell. 

C. Combustion Efficiency

The combustion efficiency was estimated from the fractions of the fuel carbon that were oxidized 

to CO and CO2: 

 ε = XCO2 /(XCO2 + XCO) 

The small contributions of pyrolyzed and partially oxidized combustion products are ignored. 

The uncertainty in the combustion efficiency is derived from the uncertainties in uncertainty in 

the measured volume fractions (or the yields) of CO and CO2. (Table 14). 

D. Doorway Flows 

Computation of mass flows through openings uses the velocity and density profiles in the opening:30

∫ ∫ = =

t

N

t

N

h

h v

amb

amb

h

h

v vWdv

T

T

m& ρvWdv ρ

43
Doorway profiles of the velocity, v, were measured with a series of bi-directional probes from

the design of Heskestad.18 Corresponding temperature measurements and the ideal gas law 

provided the densities, ρ. A corollary of the overall mass flow calculation was used to calculate 

the flow of individual gases with additional measurement of the gas concentration as: 















 =

v

g

g v g M

M

m& m& x

We then used an average value over each sampling period for the yield calculations. 

The uncertainty in these flow measurements is not small. Since the pressure drop across an 

opening passes through zero as the flow changes direction at the height of the neutral plane, 

measurement of the velocity profile in a doorway is particularly difficult. Estimation of the 

pressure in the extreme lower resolution of the instrumentation (as the pressure drop approaches 

zero) adds to the uncertainty of the measurement. For the same range of experiments noted 

above for heat release rate, the repeatability of the vent mass flow calculation averaged 35 %.28

The measurement uncertainty in the current experiments is expected to be comparable to this. 

The overall uncertainty in the doorway flow measurements also includes the effect of variation in 

the ignition and fire growth. The overall uncertainty was estimated using data from replicate 

tests. 

E. Global Equivalence Ratio 

The fuel to air global equivalence ratio is defined as: 

 m fuel/ air & m&

 _________ 

[ m fuel/ m air]stoichiometric & &

 

The terms in the numerator are the mass loss rate and the doorway flow. The denominator is 

calculated from the empirical formula of each fuel from Section II.C. The uncertainty in the 

equivalence ratio is the sum of the uncertainties in the mass loss rate, the doorway flow and the 

empirical formula. 

F. Notional Gas Yields 

The notional, or maximum possible, gas yields (Table 10) were calculated as follows: 

 CO2: Assume all the carbon in the test specimen is converted to CO2. Multiply the 

mass fraction of C in the test specimen (Table 2 or Section II.C) by the ratio of the 

molecular mass of CO2 to the atomic mass of carbon. 

44
 CO: Assume all the carbon in the test specimen is converted to CO. Multiply the mass 

fraction of C by the ratio of the molecular mass of CO to the atomic mass of carbon. 

 HCN: Assume all the nitrogen in the test specimen is converted to HCN. Multiply the 

mass fraction of N by the ratio of the molecular mass of HCN to the atomic mass of

nitrogen. 

 HCl: Assume all the chlorine in the test specimen is converted to HCl. Multiply the 

mass fraction of Cl by the ratio of the molecular mass of HCl to the atomic mass of

chlorine. 

Table 10. Estimated Notional Yields of Toxic Products (mass fraction) 

Bookcase Sofa PVC Sheet Cable 

CO2 1.72 2.00 1.55 2.11

CO 1.09 1.27 0.98 1.33

HCN 0.057 0.193 ----- 0.040

HCl 0.0026 0.0070 0.537 0.332

The uncertainty in the notional yield values is determined by the uncertainty in the prevalence of

the central element (in the bullets just above) in the combustible. These uncertainties were 

estimated in Section II.C.

F. Measured Gas Yields 

For the open-door tests, the yields of the gases were determined using the following steps: 

 Define the pre- and post-flashover time intervals. 

 Calculate the instantaneous mass flow of each gas from the room during those two 

intervals using the calculated instantaneous total mass flow through the doorway and the 

concentration measurements at location 2. 

 Average the resulting mass flow of each gas over each of the two time intervals. 

 Determine the average test specimen mass loss rate during each of the two time intervals. 

 Calculate the ratios of the average gas mass flows to the average mass loss rate during 

each of the two intervals. 

For the closed-room tests: 

 Calculate the position of the upper layer interface as the height where the measured 

temperature has risen significantly above ambient. For these calculations, this was taken 

as a rise of at least 20 % of the temperature rise from the floor to the ceiling. 

45
 Assume that the temperature of the upper layer can be represented by the average top-tobottom temperature as measured by the thermocouples in the tree in the burn room. 

 Assume that the upper layer is defined by the height at which the temperature was 20 % 

of the range defined by the highest and lowest thermocouples.31

 Assume the upper layer is well mixed. 

 Use the measured volume fraction of the individual gases (location 1) and the ideal gas

law to calculate the mass of each species in the upper layer. 

 Calculate the ratio of these masses to the specimen mass loss, as a function of time. 

 Use the final time-dependent yield as an indicator of the average species yield during the 

test, or (if there is marked variation with time) segment the test into separate yield 

values. 

For the PVC sheets:

• Since the mass loss was negligible before flashover, only post-flashover results are 

determined. 

• Since the Cl content of the bookcases is very small, assume all the HCl is from the PVC 

sheet. 

• Since the N content of the PVC sheet is very small, assume all the HCN comes from the 

bookcase. 

• Since the scatter in the CO and CO2 yields is comparable to any differences between tests 

with and without the PVC sheet, yield values from the PVC sheet for these two gases are 

not calculable. 

The uncertainty in the yield values results from: 

• the uncertainty in the species concentration measurement, 

• the sensitivity of the yield to the selected time interval (determined by varying the length 

and timing of the interval), 

• the uncertainty in the specimen mass loss, 

• the uncertainty in the species mass flow out the doorway (for open door tests), and 

• the quality of the assumptions inherent in the calculation of the mass of product in the 

upper layer (for closed room tests). 

For the closed room tests, the uncertainty can be further estimated by comparing the yield values 

from the early combustion with those from the pre-flashover segments of the open door sofa 

tests. 

G. Smoke Yields 

The smoke yield is determined by the carbon balance method. This method requires a

determination of the ratio of the smoke mass in a given volume to the total mass of carbon in the 

form of gas or particulate in the same volume. This is accomplished by dividing the smoke mass

46
collected on a filter by the sum of the smoke mass and the mass of carbon contained in the forms of

CO and CO2. The equation for calculating smoke yield, ys, as expressed in terms of CO2 and CO 

concentrations, is given by: 

 . [ m +1 n ( (CO)+ (CO )]

f m

y =

s t 2

s s 2 ∆φ ∆φ

The quantity f is the carbon mass fraction of the fuel, ms is the mass of the smoke sample collected 

on a filter, nt is the number of moles of air sampled, and the constant 12 represents the molar mass 

of carbon in grams. The quantities ∆φ(CO) and ∆φ (CO2) are the volume fractions of CO and CO2

of the gas sample taken during the test minus the ambient background concentrations of these 

gases. In this equation, the other carbon containing gases are neglected. This is a good 

approximation for overventilated burning; however, for underventilated burning the concentration 

of unburned hydrocarbons could be appreciable. Leonard et al. 32 found that these three species 

accounted for 82 % of the carbon for underventilated diffusion burning of both methane and 

ethylene at a global equivalence ratio of 1.32 and values in the range of 72 % to 74 % at an 

equivalence ratio of 1.52. This indicates that for the post flashover measurements, the smoke yields 

may be overestimates. There is one other approximation in using the equation above for

computing ys. The denominator is the sum of the carbon masses from the smoke, CO2, and CO. 

The carbon fraction of the smoke mass ms is at least 95 % carbon. This implies that the ms term in 

the denominator has been overestimated by as much as 5 %. However, over 80 % of the carbon 

produced by the combustion is in the form of CO2 and the maximum 5 % overestimate of the 

carbon mass corresponds to a 1 % overestimate of the total carbon mass. Thus, the fact that the 

carbon content of smoke is 95 % or greater carbon has at most a 1 % affect on the value of Ys

47
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48
IV. RESULTS 

In the following discussion and tables, the analysis will not include some data for the following 

reasons: 

• In the early, scoping tests there were no combustion product measurements taken. 

• An instrument may have failed during a given test. In such a case, we attempted to use 

results from similar tests to avoid having to discard the entire test. These cases are noted 

in the text and tables that follow. 

• Due to the low burning rates during the early segments of some tests, the gas sampling 

probes were not clearly in the upper layer of the corridor, as indicated by the temperature 

profile from the thermocouple trees. This was especially true for pre-flashover 

measurements at Location 4. In these cases, the data were discarded. 

• The data from Location 3 were determined to add little to the results. 

• We don’t use the data from Location 1 except in the closed room tests. It is conceptually 

possible to use the location 1 CO and CO2 concentration to obtain additional information 

on CO yields in all tests. However, analyzing the accumulated effluent to extract time

dependent concentration data is likely to be accompanied by a high level of uncertainty. 

Thus, such calculations are not performed in this report. 

The following is a repeat of the test numbering key, with format [X(Y)Zn]: 

X: Fuel [S = sofas; B = bookcases; P = power cable] 

Y: Q = heat release rate test (ceiling hole open) 

Z: M = combustibles located near middle of burn room

W = combustibles located near rear wall of burn room

P = combustibles include PVC sheet 

C = doorway closed 

n = test number for that set of combustibles and location 

 

A. Pre- and Post-flashover Time Intervals

There were four approaches from which to define a period of pre-flashover burning and one of 

post-flashover burning: 

• From the test log. During the course of each test, the test manager noted the beginning

and end of these two intervals. 

o The beginning of the pre-flashover period was designated when sustained burning 

of the fuel was observed followed the turning off and removal of the ignition 

burner. 

o The end of the pre-flashover period was designated as the test manager observed 

high intensity burning in the room and the approach of flashover approaching. 

49
o The beginning of the post-flashover period was flagged quickly after the point of 

flashover itself. This was most often identified by flaming of the crumpled 

newspaper telltale and by flames emerging from the doorway. 

o The end of the post-flashover period was recorded when the fuel began to be 

depleted and flames were no longer visible in the upper area of the doorway or by 

a decrease in the room upper layer temperature. 

• From the event markers. These reflected the data system operator’s response to the 

signals from the test manager and should produce similar time intervals. 

• From the gas concentration data. During well ventilated flaming, the [CO]/[CO2] ratio

should be 0.1 or lower and should be relatively steady. As flashover approaches, the ratio 

should increase and then plateau following flashover. As the test specimen burns out, the 

ratio should recede. 

• From the temperature data. The time interval was narrowed when the thermocouples 

near the sampling probe indicated that the probe was not sampling from the upper layer. 

The results of these considerations are shown in Table 11. Generally, we used the markers from

the first approach if the middle three were similar (or didn’t affect the results), then narrowed the 

interval, when warranted, by the temperature data. The smoke yield results were assumed to be 

insensitive to modest changes in the sampling interval. 

B. Test Data 

During the course of a series of experiments of this complexity, it is not uncommon for one or 

more instruments to malfunction during a given test. Table 12 lists the instrument failures and 

how we compensated for them (if at all). 

In each of the following tables: 

• A blank cell indicates data that would have been derived from an uninstalled or nonfunctioning analyzer. 

• A pound sign (#) indicates data that have been reconstructed as noted in Table 12. 

• An asterisk (*) marks data derived from sampling that was not assuredly from the upper 

layer or for which the signal was too close to the background. 

Table 13 is a compilation of the calculated pre-flashover data: 

• average mass loss rates from the test specimens, 

• combustion product mass flows through the doorway, and 

• volume fractions of major product gases at the four sampling locations. 

Table 14 is a similar table of post-flashover data. It should be noted that tests SW1, SW2, and 

SW3 did not go to flashover. Their data in Table 14 is for later pre-flashover combustion. 

50
Table 15 contains the calculated yields of the major gaseous combustion products from the open 

room tests. 

Table 16 contains the calculated yields of the major gaseous combustion products from the 

closed room tests. 

Table 17 contains the calculated soot yields. 

Table 18 is a compilation of the calculated peak rates of heat release, combustion efficiencies, 

equivalence ratios, and concentration ratios of CO to CO2. 

Table 19 shows the level of consistency between the NDIR and FTIR analyzers. 

Table 20 contains the results of calculations of the change in concentration of the combustion 

products along the length of the corridor. 

Table 21 contains the calculated fractions of the notional yields of the product gases. 

Table 22 shows the variance in yield values within sets of replicate tests. 

The uncertainty in the measured concentrations varies with the magnitude of the concentration 

being measured and, for the FTIR measurements, the degree of spectral interference from other 

species. As noted in Section II.E.6, the uncertainties in the NDIR concentrations are generally 

low. The instrument linearities are well below 1 % of the measured value. The volume fraction

noise level is about 1 x 10-5 for both the CO and CO2 analyzers. 

The FTIR uncertainties varied with the specific measurement and test. These are shown in Table 

23. 

Plots of the concentrations of the product gases at locations 2 and 4 are included in Appendix A. 

51
Table 11. Time Intervals (s) over Which Analyses Were Performed 

From Test Log From Data Collection From Event Markers From Gases 

Test Pre Post Pre Post Pre Post Pre Post Pre BW1 n.a. – n.a. n.a. – n.a. 171 – 279 306 – 425 n.a. – n.a. n.a. – n.a. 171 – 279 306 – 425 171 – 2SW1 114 – 198 285 – 350 110 – 198 285 – 347 114 – 198 285 – 350 114 – 180 285 – 350 114 – 1SW2 154 – 260 380 – 500 n.a. – 255 316 – 437 154 – 260 380 – 500 154 – 230 380 – 450 154 – 2SW3 90 – 185 280 – 400 90 – 185 280 – 400 90 – 185 280 – 400 90 – 185 280 – 400 90 – 1BW2 690 – 960 n.a. – n.a. 331 – 600 n.a. – n.a. 690 – 960 n.a. – n.a. 690 – 900 n.a – n.a 690 – 9BW3 495 – 540 555 – 735 496 – n.a. 556 – 736 495 – 540 555 – 735 495 – 530 570 – 640 495 – 5BW4 310 – 310 360 – 500 309 – 339 n.a. – n.a. 310 – 340 360 – 500 310 – 340 385 – 450 310 – 34BW5 513 – 617 n.a. – n.a. 517 – 618 n.a. – n.a. 638 – 742 n.a. – n.a. 638 – 742 n.a – n.a 638 – 74BW6 144 – 449 519 – 599 157 – n.a. 533 – n.a. 295 – 525 670 – 750 295 – 525 670 – 750 295 – 52PQ1 149 – 214 306 – 486 148 – 214 306 – 485 59 – 125 217 – 396 59 – 115 250 – 396 59 – 1PQ2 81 – 402 624 – 749 79 – 400 621 – 749 81 – 402 624 – 749 81 – 330 624 – 749 81 – 3PW1 280 – 400 490 – 670 279 – 399 488 – 669 280 – 400 490 – 700 280 – 380 490 – 700 280 – 3PW2 n.a. – 520 770 – 950 90 – 521 771 – 951 90 – 520 770 – 950 90 – 480 810 – 950 90 – 4SW10 65 – 111 170 – 250 65 – 111 170 – 250 65 – 111 170 – 250 65 – 111 170 – 220 65 – 1SW11 56 – 110 188 – 264 56 – 111 188 – 265 56 – 110 188 – 264 56 – 110 188 – 230 56 – 1SW12 91 – 156 232 – 311 96 – 160 235 – 316 91 – 156 232 – 311 91 – 156 250 – 280 91 – 1SW13 58 – 230 285 – 385 58 – 231 286 – 382 33 – 58 285 – 385 33 – 55 305 – 355 33 – 5SW14 182 – 262 313 – 478 175 – 255 306 – 471 182 – 262 313 – 478 182 – 250 313 – 380 182 – 2BP1 219 – 315 342 – 475 219 – 317 341 – 476 219 – 315 342 – 475 219 – 285 342 – 475 219 – 2BP2 389 – 740 1453 – 1633 389 – 740 1455 – 1632 389 – 740 1453 – 1633 389 – 740 1453 – 1570 389 – 74SC1 68 – 509 n.a. – n.a. 68 – 509 n.a. – n.a. 68 – 509 n.a. – n.a. 68 – 509 n.a – n.a 68 – 5SC2 480 – n.a. n.a. – n.a. n.a. – n.a. n.a. – n.a. 0 – 600 n.a. – n.a. 0 – 600 n.a – n.a 0 – 6BW7 240 – 650 675 – 915 n.a. – n.a. n.a. – n.a. 240 – 650 710 – 915 240 – 650 710 – 915 240 – 6BP3 240 – 420 435 – 555 n.a. – n.a. n.a. – n.a. 240 – 420 435 – 555 240 – 420 435 – 555 240 – 42n.a.: not available

52
Table 12. Occurrence and Consequences of Malfunctioning Instruments 

Test # Installed Instruments Malfunctioning Instrument(s) Calculation SW1 All None Both collection periods pr

calculations

SW2 All None Both collection periods pr

calculations

SW3 All None Both collection periods pr

calculations

BW2 Hood, Location 1 & 2 

NDIR 

None

BW3 All but FTIR None BW4 All NoneBW5 Hood, load cell, 

Location 1 NDIR 

None

BW6 All but FTIR None PQ1 All NonePQ2 All NonePW1 All NonePW2 All Load cell 

Location 1 sampling, post-flashover 

Adjusted PW2 loss rate su

equaled that from test PWDiscarded data.

SW10 All None SW11 All Velocity probes at 0.98 m and 0.83 m and 

doorway temperature 1.58 m from floor 

Doorway flows calculated velocity and temperature idoorway 

SW12 All NoneSW13 All Load cell “stuck” during pre-flashover period 

(low mass loss) 

Mass loss set equal to the SW10, SW11, SW12, and 

53
Test # Installed Instruments Malfunctioning Instrument(s) Calculation 

SW14 All Load cell “stuck” during pre-flashover period 

(low mass loss) 

Pre-flashover mass loss raaverage mass loss of SW1

BP1 All NoneBP2 All PVC load cell 

Filter on CO/CO2 sampling train at Location 2 

partially clogged during post-flashover period 

Substitute PVC mass loss normalized by the ratio of from the main load cell.Post-flashover NDIR gas by 30 s to correlate with d

SC1 Location 1 analyzers; 

load cell 

None

SC2 Location 1 analyzers, 

load cell 

None

BW7 All Location 1 sampling, post-flashover Discarded data. BP3 All PVC load cell; Location 1 instruments Substitute PVC mass loss 

normalized by the ratio of from the main load cell.

54
Table 13A. Pre-flashover Test Results: Mass Loss Rates and Doorway Flows 

Mass loss rate (kg/s) Doorway Flows (kg/s)

CO2 CO2 CO CO H

Test ↓ Main Fuel PVC Sheet Total 

NDIR FTIR NDIR FTIR FT

SW1 7.22E-03 6.51E-01 1.50E-03 1.59E-03 5.60E-05 2.15E-05 1.77SW2 1.06E-02 6.73E-01 1.49E-03 1.07E-03 1.67E-05 1.17E-05 5.88SW3 1.80E-02 6.88E-01 2.33E-03 4.16E-04 9.29E-06 1.18E-05 7.51BW2 1.06E-02 7.77E-01 1.05E-03 4.95E-05BW3 8.83E-02 1.03E+00 4.73E-03 1.34E-04BW4 7.67E-02 8.32E-01 3.18E-02 1.89E-02 9.08E-04 3.18E-04 4.18BW5 1.52E-03 4.85E-01 7.35E-04 1.94E-05BW6 3.20E-03 7.81E-01 1.85E-03 1.50E-04PQ1 2.60E-02 7.03E-01 2.05E-03 2.60E-04 1.21E-04 8.08E-06 1.29PQ2 2.48E-03 3.40E-01 5.06E-04 4.73E-04 2.69E-05 1.56E-05 1.49PW1 2.53E-02 7.11E-01 2.68E-03 2.07E-03 1.73E-04 8.04E-05 2.42PW2 3.41E-02# 1.39E+00 3.62E-03 2.55E-03 1.00E-04 1.23E-04 1.48SW10 1.48E-02 5.74E-01 1.04E-03 4.22E-04 9.66E-06 6.81E-06 7.18SW11 1.10E-02 5.43E-01 3.19E-04 2.18E-04 3.54E-06 3.18E-07 2.91SW12 6.94E-03 5.48E-01 1.43E-03 6.46E-04 7.34E-06 5.66E-06 7.51SW13 1.51E-02# 3.76E-01 3.35E-04 8.68E-06 3.36E-06 5.76E-06 1.71SW14 1.51E-02# 7.64E-01 1.49E-03 6.88E-04 6.81E-05 1.49E-05 1.03BP1 4.76E-02 3.25E-03 8.64E-01 7.77E-03 2.39E-03 1.17E-04 4.52E-05 1.44EBP2 1.23E-02 8.36E-04# 7.13E-01 1.38E-02 2.42E-02 5.37E-04 5.91E-04 8.61SC1 4.08E-03 SC2 2.92E-03 BW7 1.14E-02 5.58E-01 6.14E-03 1.15E-02 2.61E-04 2.76E-04 4.27BP3 2.87E-02 1.96E-03# 7.35E-01 7.15E-02 1.14E-02 1.91E-04 1.91E-04 2.84

55
Table 13B. Pre-flashover Test Results: Volume Fractions of Product Gases at Locations 1 and 

Location 1 Location 2 

Test CO2 CO2 CO CO HCl HCN CO2 CO2 CO CO ↓ NDIR FTIR NDIR FTIR FTIR FTIR NDIR FTIR NDIR FTIR SW1 1.45E-02 3.24E-04 2.77E-03 2.76E-03 1.65E-04 5.98E-0SW2 2.17E-02 3.45E-04 2.10E-03 1.48E-03 3.14E-05 2.28E-0SW3 2.46E-02 5.13E-04 3.19E-03 5.52E-04 2.04E-05 2.52E-0BW2 n.a. n.a. 6.90E-04 5.18E-05BW3 1.31E-01 1.26E-02 6.26E-03 2.70E-04BW4 1.32E-01 1.12E-02 8.83E-03 5.25E-03 3.96E-04 1.39E-0BW5 9.13E-03 6.22E-04 1.03E-03 4.21E-05BW6 7.96E-03 8.60E-04 1.25E-03 1.75E-04PQ1 2.96E-02 2.34E-03 3.42E-03 3.51E-04 3.21E-04 1.70E-0PQ2 6.28E-03 8.05E-04 2.83E-03 2.66E-03 2.30E-04 1.33E-0PW1 2.61E-02 2.99E-03 4.51E-03 3.67E-03 4.53E-04 2.28E-0PW2 4.73E-03 2.74E-04 1.86E-03 1.37E-03 8.24E-05 1.01E-0SW10 3.19E-02 2.68E-04 1.83E-03 7.45E-04 2.65E-05 1.93E-0SW11 2.28E-02 3.28E-04 1.87E-03 1.00E-03 3.64E-05 3.26E-0SW12 1.16E-02 2.22E-04 2.58E-03 1.17E-03 2.17E-05 1.62E-0SW13 4.24E-03 7.05E-05 7.13E-04 2.14E-05 7.06E-06 2.05E-0SW14 2.22E-02 2.03E-04 1.41E-03 6.66E-04 1.02E-04 2.31E-0BP1 5.67E-02 1.47E-03 7.58E-03 2.25E-03 1.81E-04 6.54E-0BP2 2.97E-02 2.19E-03 3.07E-03 3.95E-03 1.63E-04 1.47E-0SC1 6.40E-02 4.13E-02 3.14E-03 9.82E-04 2.40E-05 1.87E-04SC2 5.38E-02 3.35E-02 2.52E-03 5.01E-04 5.03E-05 1.26E-04BW7 3.36E-03 5.87E-03 2.14E-04 2.18E-0BP3 9.06E-02 1.46E-02 3.78E-04 3.76E-0

56
Table 13C. Pre-flashover Test Results: Volume Fractions of Product Gases at Locations 3 and 

Location 3 Location 4 

Test CO2 CO CO2 CO2 CO CO HCl HCN↓ NDIR NDIR NDIR FTIR NDIR FTIR FTIR FTIRSW1 3.30E-03 1.95E-05 4.63E-03 2.76E-03 1.49E-04 5.98E-05 4.07E-05 7.73E-06*SW2 4.51E-03 2.56E-05 7.64E-03 1.48E-03 5.88E-05 2.28E-05 7.81E-06* 1.58E-05*SW3 4.61E-03 5.52E-05 8.65E-03 5.52E-04 5.87E-05 2.52E-05 1.26E-05* 1.22E-05*BW2BW3 1.54E-02 3.60E-04 3.85E-02 3.28E-03BW4 1.49E-02 3.56E-04 3.58E-02 5.25E-03 2.56E-03 1.39E-04 1.40E-05* 1.49E-05*BW5BW6 2.14E-03 1.09E-04 4.29E-03 3.79E-04PQ1 1.45E-03 3.51E-04 1.70E-05 2.68E-06* 1.17E-05*PQ2 1.91E-03 2.66E-03 1.33E-04 8.26E-05 1.27E-05*PW1 4.72E-03 4.62E-04 1.11E-02 3.67E-03 1.27E-03 2.28E-04 5.01E-04 2.55E-05PW2 1.71E-03 8.16E-05 2.93E-03 1.37E-03 2.37E-04 1.01E-04 9.28E-05 2.83E-05SW10 1.97E-03 7.24E-06* 1.21E-02 7.45E-04 1.87E-04 1.93E-05 1.62E-05* 1.45E-05*SW11 1.73E-03 7.96E-06* 8.98E-03 1.00E-03 1.56E-04 3.26E-06 2.07E-05* 1.22E-05*SW12 2.52E-03 9.58E-06* 6.89E-03 1.17E-03 1.62E-04 1.62E-05 1.61E-05* 4.01E-06*SW13 7.44E-04 1.29E-03 2.14E-05 1.12E-04 2.05E-05 4.29E-06* 1.72E-05*SW14 1.82E-03 2.58E-05 9.55E-03 6.66E-04 3.10E-04 2.31E-05 1.21E-05* 6.60E-06*BP1 1.11E-02 2.29E-04 3.23E-02 2.25E-03 1.11E-03 6.54E-05 6.22E-06*BP2 6.56E-03 4.00E-04 1.30E-02 3.95E-03 9.43E-04 1.47E-04 1.80E-05* 1.38E-05*SC1 SC2 BW7 1.71E-04 1.11E-02 5.87E-03 6.50E-04 2.18E-04 2.40E-05 5.09E-06*BP3 1.67E-02 1.46E-02 8.28E-04 3.76E-04 4.30E-05 2.08E-05

57
Table 14A. Post-flashover Test Results: Mass Loss Rates and Doorway Flows 

Mass loss rate (kg/s)

CO2 CO CO H

Test ↓ Main Fuel PVC Sheet Total 

NDIR NDIR FTIR FT

1.97E-02 8.33E-01 3.02E-02 3.50E-02 3.41E-04 2.72

SW2 8.33E-01 1.69E-02 2.36E-02 1.47E-04

Doorway Flows (kg/s)

CO2

FTIR

SW1 4.32E-04

1.59E-02 1.48E-04 2.41

SW3 2.16E-02 8.72E-01 2.84E-02 4.44E-02 2.86E-04 5.56BW2BW3 1.17E+00 1.02E-01 6.54E-03BW4 9.91E-02 1.11E+00 4.65E-01 1.29E-01 5.22E-03 7.45BW5

1.99E-01 1.20E+00 1.13E-01 7.39E-03

PQ1 8.31E-02 1.02E+00 1.08E-01 1.23E-02 1.51E-02 1.92PQ2 6.67E-02 8.69E-01 7.17E-02 7.72E-02 7.69E-03 8.60E-03 1.15PW1 6.80E-02 9.75E-01 9.02E-02 1.10E-01 1.03E-02 1.05E-02 1.47PW2 1.04E-01 1.67E+00 1.76E-01 1.56E-02 1.62E-02 2.29SW10 6.83E-02 1.06E+00 7.56E-02 7.22E-02 4.01E-03 3.93E-03 3.74

3.34E-04

1.16E-01

2.76E-02

BW6

1.25E-01

1.38E-01

SW11 6.28E-02 1.04E+00 4.87E-02 4.92E-02 2.11E-03 1.66E-03 3.47SW12 7.49E-02 1.11E+00 7.14E-02 9.09E-02 3.95E-03 4.15E-03 3.66SW13 6.20E-02 1.09E+00 7.87E-02 7.09E-02 3.38E-03 2.82E-03 SW14 7.33E-02 1.26E+00 9.87E-02 1.21E-01 4.85E-03 4.33E-03 3.09BP1 1.72E-01 5.06E-03 1.02E+00 1.11E-01 1.08E-01 7.94E-03 5.73E-03 8.47BP2 9.98E-02 2.94E-03# 1.48E+00 2.14E-01 2.36E-01 8.08E-03 7.68E-03 1.43SC1 SC2 BW7 1.11E-01 1.63E+00 2.59E-01 1.69E-01 6.34E-03 2.79E-03 4.01BP3 2.13E-01 6.27E-3# 1.42E+00 5.15E-02 3.99E-02 1.12E-03 1.28E-03 1.62

6.03

Tests SW1, SW2, and SW3 did not go to flashover. Their data are for later pre-flashover combustion. 

58
Table 14B. Post-flashover Test Results: Volume Fractions of Product Gases at Locations 1 and 

Location 1 

Location 2 

Test CO2 C

O2 C

O

C

O

H

Cl HC

N CO2 C

O2 C

O

C

O

↓ NDI

R

F

TIR NDI

R

F

TIR

F

TIR

F

TIR NDI

R

F

TIR NDI

R

F

TIR

BW1 n.a. 

n.a. 1.31E-01 1.15E-02

SW1 4.48E-02 8.56E-04 3.10E-02 3.56E-02 6.89E-04 5.45E-04 SW2 3.31E-02 5.92E-04 1.49E-02 2.39E-02 2.06E-04 2.42E-04 SW3 4.18E-02 7.88E-04 2.52E-02 3.96E-02 4.04E-04 4.70E-04 BW2BW3 1.79E-01 1.16E-02 1.20E-01 1.20E-02BW4 1.71E-01 1.39E-02 1.27E-01 3.52E-02 1.18E-02 2.23E-03 BW5BW6 1.66E-01 1.39E-02 9.74E-02 9.98E-03PQ1 1.28E-01 1.18E-02 7.43E-02 8.59E-02 1.33E-02 1.62E-02 PQ2 1.21E-01 9.45E-03 7.23E-02 7.78E-02 1.24E-02 1.37E-02 PW1 8.98E-02 1.11E-02 6.74E-02 8.19E-02 1.20E-02 1.22E-02 PW2 2.87E-05* 3.71E-05* 7.04E-02 8.99E-02 1.25E-02 1.32E-02 SW10 1.36E-01 5.66E-03 7.11E-02 6.82E-02 5.96E-03 5.84E-03 SW11 1.14E-01 4.04E-03 6.55E-02 6.63E-02 4.82E-03 3.95E-03 SW12 1.28E-01 4.90E-03 6.60E-02 8.43E-02 5.76E-03 6.07E-03 SW13 1.10E-01 1.82E-03 7.60E-02 6.85E-02 5.17E-03 4.36E-03 SW14 1.28E-01 3.87E-03 7.73E-02 9.51E-02 6.03E-03 5.36E-03 BP1 1.63E-01 1.42E-02 1.14E-01 1.12E-01 1.27E-02 9.17E-03 BP2 1.66E-01 2.37E-02 8.17E-02 8.73E-02 5.94E-03 5.49E-03 SC1 SC2 BW7 3.07E-01 1.11E-01 7.25E-02 3.89E-03 1.71E-03 BP3 9.08E-02 8.91E-02 5.89E-03 4.69E-03 

Tests SW1, SW2, and SW3 did not go to flashover. Their d

ata are for later pre-flashover combustion.

59
Table 14C. Post-flashover Test Results: Volume Fractions of Product Gases at Locations 3 and 

Location 3 

Location 4 

Test CO2 C

O CO2 C

O2 C

O

C

O

H

Cl HC

N

↓ NDI

R NDI

R NDI

R

F

TIR

N

DIR

F

TIR

F

TIR

F

TIR

SW1 1.61E-02 2.09E-04 2.10E-02 4.16E-02 4.34E-04 2.20E-04 1.51E-05* 1.14E-05*SW2 1.14E-02 1.19E-04 1.56E-02 3.62E-02 2.02E-04 1.28E-04 7.66E-05 3.78E-07*SW3 1.58E-02 2.25E-04 1.94E-02 4.25E-02 2.42E-04 1.10E-04 1.47E-06* 1.18E-08*BW2BW3 4.49E-02 5.00E-03 5.87E-02 5.95E-03BW4 4.29E-02 3.18E-03 5.60E-02 2.57E-02 4.35E-03 1.26E-03 2.51E-05 6.76E-05BW5BW6 3.82E-02 1.45E-03 5.46E-02 4.97E-03PQ1 3.09E-02PQ2 2.94E-02PW1 3.02E-02 5.25E-03 3.82E-02 2.98E-02 6.98E-03 1.32E-03 2.62E-03 1.20E-04PW2 3.20E-02 5.42E-03 4.18E-02 3.01E-02 6.87E-03 1.57E-03 3.03E-03 1.44E-04SW10 3.89E-02 3.18E-03 4.71E-02 2.83E-02 2.79E-03 8.33E-04 2.05E-05* 5.72E-04SW11 2.13E-03 3.83E-02 3.95E-02 3.77E-02 4.52E-03 1.99E-04 6.02E-05 1.78E-04SW12 3.97E-02 3.01E-03 4.85E-02 2.58E-02 2.36E-03 2.06E-04 1.12E-05* 1.49E-04SW13 3.86E-02 2.30E-03 4.52E-02 3.73E-02 1.84E-03 4.61E-04 1.21E-04 4.53E-04SW14 3.91E-02 2.92E-03 4.92E-02 1.82E-02 3.10E-03 2.18E-04 1.40E-04BP1 4.90E-02 5.59E-03 6.23E-02 2.62E-02 6.25E-03 9.60E-04 5.68E-04 8.11E-05BP2 4.80E-02 3.08E-03 5.11E-02 2.70E-02 3.88E-03 6.61E-04 2.03E-03 4.17E-05SC1 SC2 BW7 1.76E-04 4.78E-02 6.65E-04* 1.13E-03 9.32E-06* 6.08E-06* 2.15E-06*BP3 5.77E-02 1.94E-02 6.55E-03 3.57E-04 2.13E-04 1.07E-05*B

W1

Tests SW1, SW2, and SW3 did not go to flashover. Their d

ata are for later pre-flashover combustion.

60
Table 15. Yields of Combustion Products for Open Room Tests 

Pre-flashover Post-flashover

Test CO CO2 CO CO2 HCl HCN CO CO2 CO CO2 

↓ NDIR NDIR FTIR FTIR FTIR FTIR NDIR NDIR FTIR FTIR 

SW1 2.20E-02 1.54E+00 1.73E-02 1.78E+00 1.38E-02 4.28E-03SW2 9.26E-03 1.06E+00 9.34E-03 1.49E+00 1.52E-02* 1.24E-03*SW3 1.32E-02 1.32E+00 1.55E-02 2.06E+00 2.57E-02* 4.95E-03*BW2 4.67E-03 9.89E-02BW3 1.51E-03 5.35E-02 5.63E-02 8.80E-01BW4 1.18E-02 4.14E-01 4.14E-03 2.46E-01 5.45E-04* 4.29E-04* 2.78E-01 4.69E+00 5.26E-02 1.30E+0BW5 1.28E-02 4.83E-01BW6 4.71E-02 5.80E-01 3.72E-02 5.71E-01PQ1 4.67E-03 7.86E-02 3.10E-04 1.00E-02 4.97E-05* 1.58E-04* 1.48E-01 1.30E+00 1.82E-01 1.51E+0PQ2 1.09E-02 2.04E-01 6.29E-03 1.91E-01 6.00E-03 5.73E-04* 1.15E-01 1.07E+00 1.29E-01 1.16E+0PW1 6.82E-03 1.06E-01 3.18E-03 8.17E-02 9.57E-03 3.09E-04 1.51E-01 1.33E+00 1.55E-01 1.62E+0PW2 2.94E-03# 1.06E-01# 3.60E-03# 7.49E-02# 4.34E-03# 1.01E-03# 1.50E-01 1.33E+00 1.56E-01 1.70E+0SW10 6.54E-04 7.03E-02 4.61E-04 2.85E-02 4.86E-04* 3.76E-04* 5.87E-02 1.11E+00 5.75E-02 1.06E+0SW11 3.13E-03 2.77E-01 4.61E-04 1.86E-01 2.95E-03* 1.55E-03* 3.37E-02 7.75E-01 2.64E-02 7.84E+0SW12 1.06E-03 2.06E-01 8.16E-04 9.32E-02 1.08E-03* 1.81E-04* 5.28E-02 9.53E-01 5.54E-02 1.21E+0SW13 2.24E-04# 2.23E-02# 3.84E-04# 5.78E-02# 1.14E-04#* 3.42E-04#* 5.45E-02 1.27E+00 4.55E-02 1.14E+0SW14 4.55E-03# 9.97E-02# 9.98E-04# 4.60E-02# 6.89E-04#* 2.79E-04#* 6.62E-02 1.35E+00 5.92E-02 1.65E+0BP1 2.31E-03 1.53E-01 8.89E-04 4.69E-02 7.76E-05* 4.49E-02 6.25E-01 3.17E-02 2.77E-0BP2 4.11E-02 1.05E+00 4.51E-02 1.85E+00 6.58E-03#* 3.33E-03* 7.87E-02 2.09E+00 3.00E-02 4.67E-0SC1 SC2 BW7 2.30E-02 5.41E-01 2.43E-02 1.01E+00 3.76E-03 4.99E-04* 5.74E-02 2.35E+00 2.52E-02 1.53E+0BP3 6.65E-03 2.49E+00 6.66E-03 3.98E-01 9.90E-04# 3.49E-04* 5.26E-03 2.42E-01 6.04E-03 1.87E-0Note: Tests SW1, SW2, SW3 did not go to flashover; the later pre-flashover concentration data are higher than the early 

the former have been inserted in the “Pre-flashover” half of this Table. 

61
Table 16. Yields of Combustion Products from Closed Room Tests 

SC1 Volume Fraction Yield 

Time NDIR FTIR NDIR 

(s) CO2 CO CO2 CO HCl HCN

Mass 

Lost 

(kg)

Upper

Layer

Depth 

(m) 

Mean

Upper

Layer

T (K) CO2 CO CO2 

150 3.60E-02 5.10E-04 2.40E-02 2.02E-04 7.50E-07 2.60E-06 0.44 1.85 498 1.45E+00 1.31E-02 9.65E-01 5200 6.13E-02 1.20E-03 3.90E-02 3.74E-04 2.20E-06 7.70E-05 0.84 1.85 493 1.31E+00 1.64E-02 8.36E-01 5250 7.80E-02 2.53E-03 5.04E-02 7.00E-04 1.54E-06 1.91E-04 1.17 1.85 488 1.21E+00 2.50E-02 7.83E-01 6300 8.61E-02 4.15E-03 5.95E-02 1.19E-03 2.67E-05 2.79E-04 1.40 1.85 473 1.15E+00 3.54E-02 7.97E-01 1350 8.75E-02 5.66E-03 4.60E-02 1.82E-03 4.50E-05 3.37E-04 1.60 1.85 443 1.10E+00 4.51E-02 5.76E-01 1400 8.14E-02 5.40E-03 4.10E-02 1.64E-03 3.90E-05 3.00E-04 1.70 1.85 435 9.77E-01 4.12E-02 4.92E-01 1450 7.68E-02 5.20E-03 5.85E-02 1.62E-03 4.82E-05 2.89E-04 1.76 1.85 408 9.49E-01 4.09E-02 7.23E-01 1500 7.09E-02 4.80E-03 5.18E-02 1.57E-03 4.35E-05 2.60E-04 1.83 1.85 403 8.53E-01 3.67E-02 6.23E-01 1

SC2 Volume Fraction Yield 

Time NDIR FTIR NDIR 

(s) CO2 CO CO2 CO HCl HCN CO

Mass 

Lost 

(kg)

Upper

Layer

Depth 

(m) 

Mean

Upper

Layer

T (K) CO2 CO2 

150 2.90E-02 4.20E-04 1.06E-02 7.60E-05 1.33E-05 3.34E-07 0.24 1.75 463 2.19E+00 2.02E-02 8.01E-01 3200 5.33E-02 9.90E-04 2.17E-02 1.75E-04 8.50E-05 7.50E-06 0.62 1.85 488 1.56E+00 1.85E-02 6.36E-01 3250 7.06E-02 2.20E-03 3.05E-02 2.55E-04 1.60E-04 4.36E-05 0.92 1.85 473 1.44E+00 2.85E-02 6.22E-01 3300 7.64E-02 3.50E-03 4.70E-02 5.60E-04 1.04E-04 1.56E-04 1.11 1.85 448 1.36E+00 3.97E-02 8.39E-01 6350 7.71E-02 3.90E-03 5.40E-02 7.20E-04 3.70E-05 2.14E-04 1.27 1.85 438 1.23E+00 3.96E-02 8.61E-01 7400 7.56E-02 4.05E-03 4.80E-02 9.90E-04 4.20E-05 2.32E-04 1.41 1.85 423 1.12E+00 3.83E-02 7.14E-01 9450 7.26E-02 4.14E-03 5.67E-02 8.50E-04 4.40E-05 2.35E-04 1.49 1.85 418 1.03E+00 3.75E-02 8.08E-01 7500 7.34E-02 4.32E-03 5.36E-02 9.70E-04 4.60E-05 2.41E-04 1.61 1.85 413 9.79E-01 3.67E-02 7.15E-01 8550 7.18E-02 4.35E-03 5.72E-02 9.20E-04 4.80E-05 2.50E-04 1.70 1.85 408 9.18E-01 3.54E-02 7.32E-01 7600 6.95E-02 4.35E-03 5.78E-02 1.03E-03 5.10E-05 2.53E-04 1.76 1.85 395 8.87E-01 3.53E-02 7.38E-01 8

62
Table 17. Smoke Yields 

Pre-flashover Post-flashover Sofas Bookcases Cable 

Loc 4 Loc 2 4/2 Loc 4 Loc 2 4/2 A B A B A B 

2.5E-02 5.7E-02 1.3E-02 1.9E+00

SW2 2.5E-02 4.3E-01 5.9E-02 1.8E-02 1.2E-02 1.5E+00 SW3 8.1E-03 8.7E-03 9.2E-01BW2 BW3 1.1E-02 5.0E-02 2.2E-01 1.2E-02 7.0E-03 1.6E+00 9.6E-01 7.2E+00BW4 2.2E-02 9.9E-03 6.3E-03 1.6E+00 2.3E+00BW5 BW6 PQ1 1.5E-01 4.8E-02PQ2 7.0E-02PW1 8.8E-02 2.0E-01 4.5E-01 3.7E-02 8.3E-02 4.4E-01 2.4E+00 2.3PW2 7.2E-02 2.7E-01 2.7E-01 4.2E-02 1.3E-01 3.1E-01 1.7E+00 2.0SW10 9.7E-02 3.9E-01 2.5E-01 5.2E-02 7.6E+00SW11 4.5E-02 2.4E-01 1.9E-01 2.7E-02 8.8E+00SW12 2.9E-01 2.8E-01 1.1E+00 3.9E-02 5.0E-02 7.7E-01 7.6E+00 5.5E+00SW13 8.8E-02 2.2E-01 3.9E-01 3.1E-02 2.9E-02 1.1E+00 2.8E+00 7.8E+00SW14 7.7E-02 5.4E-02 6.8E-02 7.9E-01BP1 1.1E-02 5.9E-02 1.8E-01 6.5E-02 1.0E-01 6.2E-01 BP2 3.3E-02 5.9E-02 5.7E-01 9.0E-02 1.5E-01 6.2E-01 SC1 SC2 BW7 1.0E-02 2.9E-02 3.6E-01 8.5E-03 1.6E-02 5.2E-01 1.2E+00 1.7E+00 1.2E+00BP3 7.7E-03 1.2E-01Mean 5.2E+00 7.4E+00 1.6E+00 4.5E+00 1.8E+00 2.2σ 3.4E+00 1.4E+00 6.9E-01 3.8E+00 5.8E-01 2.2SW1 4.4E-01

A: ratio of pre-flashover to post-flashover yield at position 4 B: same ratio at position 2

63
Table 18. Combustion Characterization 

Combustion Efficiency Global Equivalence Ratio [CO[/[CO

Test 

↓

Peak Rate of 

Heat Release

(MJ/kg) Pre-flashover Post-flashover Pre-flashover Post-flashover Pre-flashover 

BQW1 1880BQW2 190SQW3 1170

440

SQM1 380SQM2 2010

0.94 0.11 0.02

SW2 0.98 0.09 0.01SW3 0.99 0.12 0.01BW2 0.93 0.04 0.08BW3 0.96 0.91 0.23 0.27 0.08BW4 0.96 0.91 0.25 0.24 0.04

0.96 0.01 0.04

BW6 0.89 0.91 0.01 0.44 0.13PQ1 1510 0.91 0.85 0.16 0.35 0.09PQ2 1390 0.92 0.86 0.03 0.33 0.08PW1 0.91 0.85 0.15 0.30 0.10PW2 0.96 0.85 0.03SW10 0.99 0.92 0.12 0.31 0.01SW11 0.98 0.93 0.10 0.19 0.01SW12 0.99 0.92 0.06 0.32 0.00SW13 0.98 0.94 0.11 0.27 0.01SW14 0.93 0.93 0.00 0.28 0.07BP1 0.98 0.90 0.18 0.54 0.03BP2 0.94 0.94 0.05 0.21 0.05SC1SC2BW7 0.94 0.96 0.05 0.18 0.06BP3 1.00 0.97 0.12 0.46 0.00SQW4 SW1BW5

64
Table 19. NDIR/FTIR Volume Fraction Ratios (Location 2) 

Pre-flashover Post-flashover Test 

 ↓ CO CO2 CO CO2

SW1 1.3 0.9 

SW2 1.0 0.7 

SW3 0.8 0.7 

BW2

BW4 3.0 1.7 5.3 3.6

BW5

BW6

PQ1 18.9 9.8 0.8 0.9

PQ2 1.7 1.1 1.0 0.9

PW1 1.9 1.2 1.0 0.8

PW2 1.3 6.2 1.1 0.8

SW10 1.4 2.8 1.0 1.0

SW11 12.3 2.2 1.6 1.0

SW12 1.4 2.2 1.0 0.8

SW13 0.4 33.6 1.2 1.1

SW14 4.5 2.1 1.2 0.8

BP1 6.8 8.2 1.9 1.1

16.1 5.7 1.0 0.9

SC1

BW7 1.1 1.5

BP3 1.1 7.5 1.2 1.5

Mean 4.7 4.9 1.15* 1.00*

5.5 7.5 0.27 0.23

BW3 

BP2 

SC2 

σ

* Without BW4 

65
Table 20. Ratios of Concentrations: Position 4 (Downstream)/Position 2 (Upstream) 

Pre-flashover Post-flashover

CO CO2 CO CO2 HCl HCN CO CO2 CO CO2 H

NDIR NDIR FTIR FTIR FTIR FTIR Smoke NDIR NDIR FTIR FTIR FT

SW1 0.63 0.68 0.55 1.16 * * 0.71SW2 0.90 0.94 0.55 1.52 * * 1.39SW3 0.67 0.78 0.25 1.14 * * 0.70BW2 * * * * * *BW3 12.12 6.15 * * * * 0.76 0.49 0.49BW4 6.45 4.05 8.36 3.29 * * 0.68 0.37 0.44 0.57 0.73 BW5 * * * *BW6 2.17 3.42 * * * * 0.50 0.56PPW1 2.79 2.46 1.01 2.06 1.40 * 0.22 0.58 0.57 0.11 0.36 PW2 2.88 1.57 0.90 2.15 1.90 * 0.14 0.55 0.59 0.12 0.33 SW10 7.08 6.62 * 2.53 * * 0.32 0.47 0.66 0.14 0.42 SW11 4.28 4.81 * 4.14 * * 0.51 0.94 0.60 0.05 0.57 SW12 7.44 2.67 * 1.63 * * 0.47 0.41 0.74 0.03 0.31 SW13 * 1.80 * 22.22 * * 0.64 0.36 0.59 0.11 0.54 SW14 3.02 6.76 * 2.26 * * 0.43 0.51 0.64 0.04 0.19 BP1 6.10 4.26 0.34 1.80 * * 0.29 0.49 0.55 0.10 0.23 BP2 5.79 4.23 1.53 2.85 * * 0.23 0.65 0.63 0.12 0.31 SC1SC2BW7 3.03 3.30 * 0.03 * * 0.23 0.29 0.43 * 0.01 BP3 2.19 0.18 0.37 0.91 * * 0.64 1.11 0.63 0.08 0.22 

Q1

PQ2

* Yield of the gas was sufficiently low that the ratio is meaningless.

66
Table 21. Fractions of Notional Yields 

CO2 CO HCl 

Post 0.57 ± 0.12 (4.0 ± 0.9) x 10-2 0.86 ± 0.27 (7.Pre 0.80 ± 0.17 (1.13 ± 0.35) x 10-2 2.6 ± 0.8 (1.

Sofa 

Closed (200 s)1 0.72 ± 0.07 (1.37 ± 0.08) x 10-2 (7 ± 1) x 10-2 (1.

Post 1.10 ± 0.80 (4.2 ± 1.2) x 10-2 0.85 ± 0.55 (4.4 

Bookcase 

Pre 0.29 ± 0.14 (2.2 ± 1.2) x 10-2 0.85 ± 0.64 (8.

0.65 ± 0.10 0.111 ± 0.013 0.58 ± 0.06 0.1

Cable 

Pre (5.7 ± 2.4) x 10-2 (4.1 ± 1.9) x 10-3 (1.78 ± 0.48) x 10-2 (1.

Post 2 2 4.3 ± 3.6 

PVC sheet 

Pre 2 2 4 

Post

1 Earliest time with significant combustible mass loss and before significant vitiation. Calculations are for comparison with open-door 

Section V.E for discussion of time-dependent results. 

2 Pre-flashover mass loss from the PVC sheet was negligible. Thus yields are not calculable. 3 All HCN generated in the PVC sheet tests is from the bookcase and the results are included there. 4 Mass loss and HCl concentrations were too low to obtain a meaningful value. 

67
Table 22a. Variance in Product Yields Among Replicate Tests (SW 10 to SW14) 

CO2 CO HCl 

NDIR 0.135 ± 0.092 (69 %) (1.92 ± 1.65) x 10-3 Pre- (86 %) -- 

flashover FTIR (8.2 ± 5.6) x 10-2 (68 %) (6.2 ± 2.4) x 10-4 (39 %) (1.06 ± 0.99) x 10-3 (94 %) (5.5 

NDIR 1.09 ± 0.21 (19 %) (5.3 ± 1.1) x 10-2 Post- (21%) -- 

flashover FTIR 1.17 ± 0.28 (24 %) (4.9 ± 1.2 x 10-2 (25 %) (6.0 ± 1.9) x 10-3 (32 %) (1.5 

Table 22b. Variance in Product Yields Among Replicate Tests (SW 1 to SW3) 

CO2 CO HCl 

NDIR 1.31 ± 0.20 (15 %) (1.48 ± 0.53) x 10-2 Pre- (36 %) -- 

flashover FTIR 1.78 ± 0.23 (13 %) (1.40 ± 0.34) x 10-2 (24 %) (1.82 ± 0.53) x 10-2 (29 %) (3.5 

68
Table 23a. Uncertainties in FTIR Volume Fractions of Product Gases; Pre-flashover Data. (Exp

percentag

e of the volume fractions reported in Table 12) 

Location 1 

Location 2 

Lo

Test 

↓

CO2 C

O

H

Cl HC

N CO2 C

O

H

Cl HC

N CO2 CO 

SW1 ± 0.5 

± 10

± 12

± 43

± 0.2 

± 7 

SW2 ± 0.1 ± 4 

± 4 

± 8 ± 0.2 

± 3 

SW3 ± 5 

± 3 

± 17

± 11

± 0.4 

± 15

BW2BW3BW4BW5BW6PQ1 

± 0.5 

± 5 

± 31

± 9 

PQ2 

± 0.7 

± 0.7 

± 1 ± 7

PW1 ± 0.1 ± 0.8 ± 0.7 

± 4 

± 0.2 

± 0.9 

PW2 ± 0.1 ± 0.6 

± 1 ± 3 

± 0.1 ± 0.7 

SW10 

± 3 

± 8 ± 20

± 15

± 0.3 

± 26

SW11 

± 0.3 

± 76

± 12

± 17

± 3 

± 24

SW12 

± 0.1 ± 8 ± 16

± 32

± 3 

± 218 

SW13 

± 10

± 12

± 125 

± 21

± 0.8 ± 151 

SW14 

± 0.3 

± 6 

± 23

± 23

± 0.4 

± 16

BP1

± 0.1 ± 1 ± 147 

± 19

± 0.2 

± 2 

BP2

± 0.1 ± 0.5 

± 3 

± 3 

± 0.1 ± 0.7 

SC1 

± 0.3 

± 0.1 ± 4 

± 19 

± 1 

± 35

± 400 

± 400

SC2 

± 0.5 

± 0.1 ± 4 

± 4 

± 1 ± 35 

± 500 

± 62

BW7 ± 0.1 ± 0.2 

± 3 

± 13

± 0.9 

± 17

BP3

± 0.1 ± 0.3 

± 3 

± 6 

± 0.1 ± 0.8 

69
Table 23b. Uncertainties in FTIR Volume Fractions of Product Gases; Post-flashover Data. (Ex

percentage of the volume fractions reported in Table 13) 

Location 2 Location 4 

Test ↓

CO2 CO HCl HCN CO2 CO HCl HCN

SW1 ± 0.5 ± 3 ± 4 ± 25SW2 ± 0.2 ± 0.6 ± 2 ± 8 ± 0.2 ± 3 ± 44 ± 44SW3 ± 0.1 ± 0.3 ± 0.5 ± 2 ± 0.2 ± 4 ± 10 ± 209 BW2 ± 0.2 ± 4 ± 162 ± 162 BW3BW4BW5 ± 0.2 ± 0.2 ± 25 ± 9 BW6PQ1 ± 0.1 ± 0.1 ± 0.2 ± 6 PQ2 ± 0.1 ± 0.1 ± 0.2 ± 6 PW1 ± 0.1 ± 0.7 ± 0.2 ± 8 PW2 ± 0.1 ± 0.1 ± 0.2 ± 7 ± 0.1 ± 0.6 ± 0.9 ± 12SW10 ± 0.2 ± 0.2 ± 0.6 ± 2 ± 0.1 ± 1 ± 1 ± 7 SW11 ± 0.2 ± 0.2 ± 4 ± 3 ± 0.25 ± 25 ± 25 ± 4 SW12 ± 0.2 ± 0.2 ± 5 ± 2 ± 0.3 ± 28 ± 28 ± 32SW13 ± 0.2 ± 0.2 ± 4 ± 2 ± 0.3 ± 316 ± 32 ± 19SW14 ± 0.2 ± 0.2 ± 2 ± 0.8 ± 0.3 ± 100 ± 21 ± 6 BP1 ± 0.1 ± 0.1 ± 0.1 ± 3 ± 0.2 ± 17 ± 112 ± 14BP2 ± 0.1 ± 0.9 ± 1 ± 11 ± 0.2 ± 2 ± 2 ± 30SC1 ± 0.2 ± 1 ± 2 ± 112 SC2 BW7 ± 0. ± 0.4 ± 1 ± 9 BP3 ± 0.1 ± 0.3 ± 0.8 ± 11 ± 0.8 ± 24 ± 24 ± 24

70
C. Checks on Data Reliability

There are certain ratios whose values are fixed or can be estimated. Examining these provides a 

first assessment as to the integrity of the data set

1. Cross-instrument Similarity

The ratio of the volume fraction obtained using NDIR to that measured using FTIR should be 

unity for either CO2 or CO measured at the same location (data from Table 19). The data set for 

these ratios includes experiments involving bookcases, sofas and cables. The presented 

uncertainty is the standard deviation. The post-flashover values are the highest concentrations 

with the highest signal to noise and are thus the most likely to manifest proper behavior. 

Much of the pre-flashover data from location 4 are too near background to assess agreement, and 

the vertical temperature profiles indicated that during the pre-flashover period, the location 4 

sampling probes were not safely in the hot upper layer and thus were not assuredly sampling 

room fire effluent. Tests SW1, SW2 and SW2 did not reach flashover, but did continue to 

produce pre-flashover smoke that enveloped the location 2 sampling probes. Thus, the late data 

from these three tests constitute a fair check on cross-instrument similarity. 

• For post-flashover measurements at location 2: 

o [CO]NDIR/[CO]FTIR = 1.17 ± 0.35 

o [CO2]NDIR/[CO2]FTIR = 0.97 ± 0.19 

• For late pre-flashover measurements at location 2: 

o [CO]NDIR/[CO]FTIR = 0.99 ± 0.19 

o [CO2]NDIR/[CO2]FTIR = 0.71 ± 0.11 

• For post-flashover measurements at location 4 

o [CO]NDIR/[CO]FTIR = 5.7 ± 3.7 

o [CO2]NDIR/[CO2]FTIR = 1.87 ± 0.60 

• For late pre-flashover measurements at location 4 

o [CO]NDIR/[CO]FTIR = 1.91 ± 0.26 

o [CO2]NDIR/[CO2]FTIR = 0.46 ± 0.03 

2. Location Similarity

The ratio of the volume fractions of CO2 measured at two locations (Table 20) should reflect 

dilution only and thus should be the same for all tests and instruments. [See Section IV.E for the 

ratios for other gases.]

71
For post-flashover NDIR measurements: 

 [CO2]loc4/[CO2]loc2 = 0.59 ± 0.07 

For late pre-flashover NDIR measurements: 

 [CO2]loc4/[CO2]loc2 = 0.83 ± 0.16 

For post-flashover FTIR measurements: 

 [CO2]loc4/[CO2]loc2 = 0.38 ± 0.16 

For late pre-flashover FTIR measurements: 

 [CO2]loc4/[CO2]loc2 = 1.25 ± 0.19 

3. Notional Yield Fractions 

From the post-flashover gas concentration data, most of the fuel carbon appears as CO2, with 

lesser amounts appearing as CO and carbonaceous soot. Thus, one should expect the fraction of 

the notional yield of CO2 calculated from the concentration measurements to be slightly less than 

unity. For Cl, a value less than unity probably represents losses to the walls combined with 

losses in the sampling line. The values for CO and HCN should be well under unity, as most of 

the C and N is expected to be found in other combustion products. Table 21 presents the results, 

with the FTIR and NDIR values combined in the calculations for CO2 and CO. 

D. Test Repeatability

It is well known that there are numerous sources of variability in real-scale fire tests. These 

could also impact the repeatability of the measured toxicant yields. Time and resources did not 

provide for an exhaustive evaluation of test repeatability. Table 22a shows the mean yields of

the principal toxicants and the uncertainty (standard deviation) from five replicate tests (SW10-

SW14) of one fuel and configuration. Figure 15 shows the mass loss curves for the five tests 

with the time scales shifted to a common ignition time. 

Because the probes at location 2 were not always in the effluent stream early in a test, the later 

pre-flashover data for tests SW1-SW3 are also shown (Table 22b). Even though the number of 

cushions differed among these tests, the burning behavior was similar, as shown in Figure 16. 

Figures 17 and 18 show the time-integrated yields of the measured gases for the two closed room

tests. Figure 19 shows the evolving oxygen concentration (30 cm from the ceiling) for the two 

tests. 

72
Figure 15. Mass Loss vs. Time: Tests SW10 through SW14 

0

1

2

3

4

5

6

7

8

9

10

0 50 100 150 200 250 300 350 400

Time (s)

Mass Loss (kg)

SW10 SW11 SW12 SW13 SW14

Figure 16. Mass Loss vs. Time: Tests SW1 through SW3 

0

1

2

3

4

5

6

7

8

9

10

0 50 100 150 200 250 300 350 400 450 500

Time (s)

Mass Loss (kg)

SW1 SW2 SW3

73
Figure 17. Time-integrated Yields for Closed-Room Test SC1 

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

0 100 200 300 400 500 600

time (s)

Yi

eld (

g/g)

CO2 (NDIR) CO (NDIR) x 10 CO2 (FTIR) CO (FTIR) x 10 HCl x 1000 HCN x 100

Figure 18. Time-integrated Yields for Closed-Room Test SC2 

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

0 100 200 300 400 500 600

time (s)

Yi

eld (

g/g)

CO2 (NDIR) CO (NDIR) x 10 CO2 (FTIR) CO (FTIR) x 10 HCl x 1000 HCN x 100

74
Figure 19. Oxygen Concentration in Closed Room Tests

0.00

0.05

0.10

0.15

0.20

0.25

0 100 200 300 400 500 600 700

Time (s)

M

ole Fraction

SC1

SC2

E. Species Losses During Transport 

Loss of a combustion product during travel down the corridor is quantified by the ratio of the 

concentration at location 2 to location 4 relative to the same ratio for CO2. Analysis of the data 

in Tables 13 and 14 produces the results in Table 24: 

Table 24. Ratios of Downstream (Location 4) to Upstream (Location 2) 

Concentrations (Post-flashover Data) 

Analyzer Sofa Bookcase Cable Bookcase/PVC

CO2 NDIR 0.65 ± 0.05 0.48 ± 0.05 0.58 ± 0.01 0.60 ± 0.04 

CO NDIR 0.54 ± 0.21 0.41 ± 0.09 0.57 ± 0.02 0.75 ± 0.26 

CO2 FTIR 0.41 ± 0.14 0.73 0.35 ± 0.02 0.25 ± 0.24 

CO FTIR 0.07 ± 0.04 0.57 0.12 ± 0.01 0.10 ± 0.02 

HCl FTIR 0.08 ± 0.05 0.53 ± 0.50 0.21 ± 0.02 0.11 ± 0.09 

HCN FTIR 0.17 ± 0.09 0.43 0.45 ± 0.02 0.39 ± 0.18 

Smoke Filter 0.47 ± 0.10 0.45 ± 0.22 0.18 ± 0.04 0.39 ± 0.18 

75
F. Estimates of Toxic Gas Yields with Uncertainties 

Table 25 contains the yields of the combustion products calculated using the data from location 

2. The estimated uncertainties reflect the repeatability of similar tests, discounting of disparate 

individual test results, and degree of proximity of the measured values to the background levels. 

It was noticed (and is discussed in the following Section) that the post-flashover CO yields are 

lower than expected. For that reason we have compiled in Table 26, for the post-flashover 

portion of each test, an estimate of the fraction of carbon atoms appearing in CO (approximated 

as [CO]/ {[CO] + [CO2]}) at both location 1 (near the ceiling of the burn room) and location 2 

(outside the burn room). We also include the values from location 3 to assess the extent to which 

the fire plume chemistry has been quenched. 

G. Archiving of Test Data 

All of the raw data (ca. 130 instruments, thousands of readings per instrument) from the tests 

reported here are to be available in a companion report.33 This will be in the form of

spreadsheets and graphs. 

76
Table 25. Yields of Combustion Products Calculated from Location 2 Data 

Gas Fire Stage Sofa Bookcase PVC Sheet Cable 

Pre-flashover 1.59 ± 25 % 0.50 ± 50 % -- 0.120 ± 45 %

CO2 Post-flashover 1.13 ± 25 % 1.89 ± 75 % -- 1.38 ± 15 % 

Pre-flashover 1.44 x 10-2 ± 35 % 2.4 x 10-2 ± 55 % -- 5.5 x 10-3 ± 50 % 

CO 

Post-flashover 5.1 x 10-2 ± 25 % 4.6 x 10-2 ± 30 % -- 1.48 x 10-1 ± 15 

Pre-flashover 3.5 x 10-3 ± 50 % 4.6 x 10-4 ± 10 % -- 6.3 x 10-4 ± 50 % 

HCN 

Post-flashover 1.5 x 10-2 ± 25 % 2.5 x 10-3 ± 45 % -- 4.0 x 10-3 ± 30 % 

Pre-flashover 1.8 x 10-2 ± 30 % 2.2 x 10-3 ± 75 % -- 6.6 x 10-3 ± 35 % 

HCl 

Post-flashover 6.0 x 10-3 ± 35 % 2.2 x 10-3 ± 65 % 2.3 ± 85 % 2.1 x 10-1 ± 15 % 

Pre-flashover < 7 x 10-2 < 2 x 10-2 -- < 4 x 10-3

NO2 Post-flashover < 1 x 10-3 < 1 x 10-3 -- < 1 x 10-3

Pre-flashover < 8 x 10-3 < 2 x 10-3 -- < 4 x 10-4

Acrolein 

Post-flashover < 1 x 10-4 < 1 x 10-4 -- < 1 x 10-4

Pre-flashover < 2 x 10-2 < 2 x 10-3 -- < 8 x 10-4

Formaldehyde Post-flashover < 8 x 10-4 < 4 x 10-4 -- < 7 x 10-4

77
Table 26. Fraction of Combustible Carbon Appearing in Carbon Monoxide (NDIR, 

Post-flashover Data) 

Test Location 1 Location 2 Location 3 

SW10 0.040 0.077 0.076

0.069

0.037 0.080 0.071

0.016 0.064 0.056

SW14 0.029 0.072 0.070

BW3 0.061 0.091

0.075 0.085 0.069

0.077 0.093 0.037

BP1 0.080 0.100 0.102

0.125 0.068 0.060

0.152

PQ2 0.073 0.143

0.101 0.147

PW2 0.151 0.145

SW11 0.034 

SW12

SW13

0.100

BW4

BW6

BP2

PQ1 0.084 

PW1 0.151

78
V. DISCUSSION 

A. Overall Test Quality 

The most important outcome of this series of tests is a reliable, well-documented set of

combustion product yields. This includes the numerical values themselves, the specific 

combustion conditions under which they were obtained, the uncertainty in their calculated 

values, and the repeatability of the tests. 

Next, most important is the initiation of the development of a standard protocol for obtaining 

yield values from a wider variety of test specimens. This includes test conduct procedures, 

experimental design, instrumentation, species sampling, and data reduction. 

Third, it is important to evaluate the quality of the derived knowledge in the context of its 

intended use. The yield information would be used with a fire model (zone or CFD) to generate 

the time-dependent environment generated by a fire. Equations such as those in ISO/TS 135716

would then be used to assess whether the combination of occupancy design, contained 

combustibles, and occupant/responder characteristics lead to the desired level of life safety. 

The documentation has been provided in the earlier sections. The following examines the 

context and quality of the results. 

B. Test Repeatability

Even under controlled laboratory conditions, attaining a reasonable degree of consistency in 

replicate fire tests requires both conceptual understanding of the phenomena and attention to 

detail. Even then, much of the success is attributed to art as well as science and engineering. In 

the current series, two to five tests of each of the complex fuels led to an appraisal of how likely 

the results from a single test might be representative. The results were within the range needed 

for the intended application. 

By all measures, the repeatability of the sofa tests SW10 through SW14 is excellent. From

Figure 15, there is qualitative agreement of the shapes of the mass burning rate curves. Table 17 

shows that the global equivalence ratios for the tests are also similar. Table 22a shows that the 

variability in the post-flashover yields of CO2, CO, and HCN are within ± 25 %, while the 

variability in the yield of the more difficult-to-sample HCl is ± 35 %. The pre-flashover yield 

values, for reasons discussed below, are repeatable to within a factor of two. 

Table 22b shows that the pre-flashover yield values are of comparable repeatability, although the 

uncertainty in the HCN result is somewhat higher. 

For sofa tests SW1 through SW3, which did not reach flashover, the mass burning rate curves 

(Figure 16) are similar and the later pre-flashover burning data (Table 22b) show the CO2, CO 

and HCl yields all repeatable to within ± 36 % and the HCN yield repeatable to within ± 45 %. 

79
The final yields (Table 16) from the two closed room sofa tests (SC1 and SC2) are repeatable to 

within ± 20 %. 

The results of the four cable tests (PQ1, PQ2, PW1, PW2) indicate qualitatively similar results 

(Table 25). Post-flashover yield repeatability is typically ± 15 % to 30 %, with the pre-flashover 

repeatability somewhat higher, but within a factor of two. 

For the four bookcase tests (BW3, BW4, BW6, BW7) in which NDIR data were obtained, the 

repeatability was not as good as for the other combustibles. The post-flashover and preflashover yield repeatability values for CO2 are ca. ± 75 % and ± 30 %, respectively; the CO 

values are ca. ± 30 % and ± 55 %. There were only two bookcase tests for which we obtained 

FTIR data. Fortunately, the yield agreement was good. For HCN, the post-flashover and preflashover yield repeatability values are ca. ± 45 % and 10 %, respectively. For HCl, they are 65 

% and 75 %. 

The post-flashover HCl yields from the three PVC sheet tests spanned over an order of 

magnitude. See the discussion below. 

In summary, the repeatability of the yields values obtained here for three of the combustibles is 

sufficient for determination of whether a bench-scale apparatus is producing results that are 

similar to or different from the real-scale results here. The PVC sheet, from which only HCl 

yield data could be obtained, can only provide an indicator of appropriateness and then only for 

post-flashover simulation. 

The repeatability results indicate an uncertainty in the fractional effective dose (FED) 

calculations in ISO/TS 13571 that is comparable to the uncertainty in the equations themselves. 

This is especially so since a large fraction of fire deaths result from post-flashover fires (reducing 

the importance of the larger variance in the pre-flashover gas yields) and since CO is always a 

major (if not the dominant) incapacitating toxicant (reducing the importance of the variance in 

the other toxicants). 

C. Species Sampling and Measurement 

1. CO2 and CO 

The CO2 and CO data have low variability and good consistency between analyzers at location 2 

during the post-flashover period. The CO2 concentrations are high (ca. 5 % to 10 % by volume) 

and well above the sensitivity limit of the analyzers, and the sampling is reliably from the well 

established upper layer. Appropriately, the scatter among replicate tests is about 20 %, the 

lowest for any set of concentration measurements and not far from the estimated repeatability of 

the mass burning rate. The CO concentrations are also high (0.5 % to 1 % by volume) and show 

repeatability similar to the CO2 results. As indicated in Section IV.C.1, the FTIR and NDIR 

instruments show good agreement for both gases. 

80
The same was true at location 2 during the late pre-flashover period in tests SW1 through SW3, 

despite some of the concentrations being ca. an order of magnitude lower than after flashover. 

However, during the general pre-flashover burning periods for all tests, including the earlier preflashover periods in tests SW1 through SW3, distinctly higher variability was observed. 

Concentrations were yet another order of magnitude lower. Care was needed to adjust the 

sampling time period such that the thermocline showed the probe tip was sampling from the 

upper layer. Turbulence in the effluent stream was likely to result in non-uniform mixing with 

lower layer air. The burning rates of replicate tests varied more during the early growth period 

than later on. 

 From comparison of the sensitivity limits in Table 9 and the measured concentrations in Tables 

13 and 14, one can see that there are some combinations of location, fire phase, and combustible 

for which the measurements are very close to the background. The location 2 data are sufficient 

to obtain reasonable post-flashover yield values and pre-flashover yield estimates for all three 

principal combustibles. 

An additional observation is that the location 2 pre-flashover measurements using the FTIR 

analyzer were consistently smaller than those using NDIR for both gases (Table 19) and that the 

ratio varies widely from test to test. The exceptions are the data from the late (non-flashover) 

portions of tests SW1 through SW3. This suggests that it took more time to establish the upper 

layer than was typically available before the transition to flashover occurred. However, there is 

no hard evidence to verify this hypothesis. 

At location 4 during the post-flashover period, the upper layer visually encompassed the probe 

tips, and the variation in CO2 and CO concentrations was similar to that at location 2 for the 

NDIR measurements. The FTIR concentration values for CO2 and CO were again lower than the 

NDIR values. 

The concentrations of species at location 4 during the pre-flashover periods were very low, with 

all but the CO2 values being near the detection limits of the analyzers. The replicate tests SW10 

through SW14 show some small degree of consistency. 

Each cell in Table 16 represents the volume fraction or yield integrated from the beginning of the 

test to that point in time. The values are probably somewhat high, since the sampling was 

performed at only one point near the top of the upper layer, and it was likely that there was a 

decreasing concentration gradient from the ceiling downward. The early NDIR yields for CO2

and CO are remarkably close to those for the open door sofa tests (Tables 15 and 25). As the fire 

progressed, the CO2 yield decreases and the CO yield increases, as expected from burning in an 

increasingly vitiated atmosphere. 

2. HCl and HCN 

The concentrations of these gases were only measured using FTIR. Thus, the same sampling 

considerations that were discussed above apply here. To mitigate these effects, we use the ratios 

of the concentrations and yields of HCl and HCN to the corresponding values for CO2. 

81
The HCl concentration data from the PVC sheet tests are high enough to obtain post-flashover 

HCl yields. Table 21 shows that the yield values from the multiple tests have a high degree of

scatter and that the yields are at least as high as the notional yield. This most likely indicates that 

the HCl is being pyrolyzed from the test specimen faster than the carbon-containing species. It is 

not likely that this is due to an artifact of the HCl measurement for two reasons. First, the FTIR 

instruments were carefully calibrated. Second, if the FTIR spectra were indicating high yield 

values, the CO and CO2 results should also be high. Table 19 shows that for the bookcase/PVC 

sheet tests, very high HCl yield values would be inconsistent with the more modest deviations 

from unity in the yields of these gases between the two types of instruments. 

The post-flashover location 4 measurements for HCl and HCN are high enough to obtain 

estimates of the degree of loss of the compounds down the length of the corridor. By contrast, 

nearly all the pre-flashover values can be expected to have a high degree of uncertainty and are 

not useful for even a rough estimate of losses down the corridor. 

The two closed-room sofa tests, SC1 and SC2, produced very repeatable yield results for these 

two gases, the exception being a burst of HCl early in SC2. 

3. Other Gases 

Ratio to [HCl]

The equations in ISO/TS 13571 include additional gases to be included in estimating the time

available for escape or refuge from a fire: HBr, HF, SO2, NO2, acrolein (C3H4O) and 

formaldehyde (H2CO). There was no Br, F, or S in any of the products examined in this project, 

so the first three of these gases were not expected. The presence of the latter three was not 

detected, thus establishing the upper limits of their presence at 100, 10, and 50 x 10-6 volume 

fraction, respectively. 

All three of these gases are sensory irritants. Their incapacitation concentrations from ISO/TS 

13571, their ratios normalized to HCl, and the concentration (location 2, post-flashover) ratios of 

the gases in this study are shown in Table 27. The measured pre-flashover concentrations were 

too low to obtain usable comparison. 

Table 27. Limits of Importance of Undetected Toxicants 

Volume fraction x 106

HCl NO2 C3H4O H2CO HCl NO2 C3H4O H2CO 

Incapacitating

level 

1000 250 30 250 1.00 0.25 0.030 0.25 

800 <100 < 50 1.00 < 0.12 < 0.012 < 0.06

Bookcase 20-200 <100 <10 < 50 1.00 < 5 – 0.5 < 0.5 – 0.05 < 2.5 – 0.25

<10 < 50 < 0.007 < 0.0007

< 50 1.00 < 0.0012 < 0.006 

Sofa <10 

Cable 1400 <100 1.00 < 0.04

PVC sheet 8000 <100 <10 < 0.012 

82
From this analysis, the maximum concentrations of NO2, formaldehyde and acrolein that could 

have been present would have had secondary contributions to incapacitation relative to the 

concentration of HCl in the sofa, cable and PVC sheet tests. In the bookcase tests, where the 

HCl levels are low, the other irritants could be important. However, the high levels of CO in 

those tests suggest a secondary role for the irritant gases in causing incapacitation. 

Levin et al. have developed extensive information on the effects of gas mixtures on rat lethality 

and incapacitation34. They used those data to test whether the toxic potency of a small number of 

gases could account for the lethality of the effluent from a variety of materials. The apparatus 

conditions were typical of pre-flashover combustion. Within the uncertainty in the results, ±

30 %, there as no need to invoke additional toxicants. Combined with the results obtained here 

for post-flashover conditions, it suggests that a set of upper limit criteria for these gases would be 

a reasonable criterion for the accuracy of a bench-scale apparatus. 

4. Species Measurement Using FTIR Spectroscopy

D. Combustion Conditions 

There is considerable interest in adding FTIR spectroscopic analysis to fire test apparatus. A 

major European program35 developed extensive information on the technique, and there are 

documents under development in ISO TC92 SC1 and SC3 to standardize the implementation. 

We were able to obtain usable information using this technique. There are a number of lessons 

emerging from this test series that can provide useful input to these efforts, such as the 

following: 

• The application of FTIR spectroscopy to fire testing requires the constant attention of an 

experienced professional at a level well beyond the demands of the more traditional fire 

test instrumentation. 

• To maximize the opportunity for obtaining time dependent concentration data, we 

selected a small volume cell of short optical path length and operated without a soot 

filter. While some cleaning was necessary, it was not a major impediment. The short 

path length did limit the sensitivity, but did not seriously compromise our ability to 

determine toxicologically important levels of the major gases, as noted above. 

• The long, heated lines used here (and recommended in the SAFIR report35) enabled 

quantitative collection of HCl, a compound that is generally regarded as difficult to 

determine. 

The contents of Table 18 show that the combustion efficiency declines slightly as the fire 

proceed through flashover. As is to be expected, the [CO]/[CO2] ratio increases. 

The global equivalence ratios are surprising. The local equivalence ratios during ventilation 

limited (post-flashover) combustion should be above unity. However, other research is now 

indicating that two thirds or more of the air entering a flashed over compartment is forced out of 

the compartment before approaching the fire zone.

36

83
E. Loss of Acid Gases During Transport 

In light of the above discussion, we used only post-flashover data in the estimation of the degree 

to which HCl and HCN were lost to walls or deposited on smoke aerosol. In interpreting the 

data, one must recognize that the cells in Table 24 often reflect a small number of tests. 

The first observation is that the NDIR data indicate about a factor of two dilution of these two 

fixed gases (CO and CO2) with air from the lower layer for all combustibles. This is a 

reasonable finding since the dilution both of these gases should be affected only by the traverse 

time down the corridor, and that should be uniform since the doorway flows are uniform (Table 

14A).

• The CO, HCl and HCN concentrations generally decrease by similar factors for a given 

combustible, even though the factors are combustible-dependent. [The exception to this 

is HCN from the cable and bookcase/PVC fires, the reason for which is also unknown.] 

The bookcase results are similar to the dilution of CO2. The sofa, bookcase/PVC and 

cable factors are more severe. 

From there, the picture becomes more complex. The CO2 data from the FTIR analyzers give 

results that are similar to the NDIR data. However, the data for the other effluent components 

show distinct dependence on the combustible. 

• The FTIR CO concentration changes differ significantly from the NDIR changes for the 

sofas and cable. 

The cause of this is not understood. However, soot particles and aqueous aerosols are 

characterized by their number density, surface area, and hydrophilia. In these tests, only the soot

mass was measured. It may well be that the smoke from the sofa, PVC and cable materials have 

a greater affinity for acid gases and CO than does the smoke from the bookcases. 

The inference we draw from these results is that for large fires of some combustibles, there can 

be little loss of reactive gases. This is consistent with a previously reported analysis of other 

experimental data.7

 However, for some other combustibles, loss factors of two to five beyond 

dilution are possible. Care should be taken not to extend these limited findings to other 

commercial products. In the absence of a comprehensive study of the relationship between 

smoke character and gas absorption, safety engineers are most likely to continue to assume there 

is no loss of toxicants, the more conservative approach. 

F. Yield Values 

During vigorous combustion, the yields of CO2 and HCl should approach their notional values. 

As can be seen from Table 21, the post-flashover values of CO2 from all three combustibles do 

just that, given the conversion of up to ca. 10 % of the carbon to carbonaceous smoke and CO 

and some formation of carbonaceous char residue. Under pre-flashover conditions, the CO2

fraction from the sofas was as large as expected. However, for unknown reasons the bookcase 

84
and cable fractions were far lower. In the closed room sofa tests, the yield begins at about the 

notional level, then declines to about half that as room vitiation affects the completeness of 

combustion. 

The HCl yields are close to notional under post-flashover conditions for the sofas, bookcases, 

and cable arrays. By contrast, in prior work37, ca. 40 % or less of the HCl from room-scale tests 

reached the analyzers. We attribute the present improvement to the use of calcium silicate walls 

(rather than drywall), the use of heated transfer lines to the FTIR spectrometers, and the absence 

of soot filters in those transfer lines. The somewhat lower value for the power cable may reflect 

the known HCl reaction with the calcium carbonate filler in the cable jacket. 

The pre-flashover stages of the sofa tests and the post-flashover stages of the PVC/bookcase tests 

produced HCl yields well above the notional values. The cause of these is unexplained. 

However, in both cases, relatively little of the specimen mass was volatilized, and it is possible 

that a disproportionate fraction was fire retardant (sofa tests) or HCl (PVC tests). 

Generally little of the nitrogen in the combustibles ends up in HCN. The observed exceptions

are with the urea formaldehyde resin in the bookcase particle board and the nylon in the wire 

insulation, where over 10 % of the N atoms appear in HCN. This is consistent with the results of

prior room-scale tests with a different urethane foam37 in which 5 % to 10 % of the fuel nitrogen 

appeared as HCN and where (as noted above) the sampling of reactive gases was less efficient. 

It is interesting to note that the addition of the PVC sheet to the bookcase fires leads to an order 

of magnitude increase in the yield of HCN (Table 15). Perhaps the flame inhibition by the 

chlorine atoms is reducing the ability of the flame radicals to oxidize the HCN to one of the 

nitrogen oxides. Otherwise, Table 21 shows only modest differences in the conversion of fuel 

nitrogen to HCN despite large differences in the chlorine content of the fuel. 

The early NDIR yields in the closed-room tests (Table 16) are consistent with the pre-flashover 

yields from the equivalent (later pre-flashover) phase of open room tests SW1 through SW3 

(Table 15). [Note that the first entries in Table 16 occur at 150 s; prior to that, the mass loss and 

concentration values were too small and noisy to obtain reliable ratios.] As noted above, the 

FTIR-derived CO and CO2 yields are consistently somewhat lower than their NDIR-derived 

counterparts. However, the ratios of the yields of HCN and HCl to the FTIR-derived CO2 yield 

are a fair basis for comparison and are similar to the later pre-flashover phase of tests SW1 

through SW3. Because the mass burning rate falls sharply as the oxygen concentration drops, 

the yields from SW1 through SW3 can be used to approximate the overall yields from the closed 

room tests. The volume fraction section of Table 16 does not show evidence of large increases 

in the rates of generation of HCN or CO as the fires approach extinction. 

Of most interest are the post-flashover yields of CO. A number of room-scale fire studies have 

indicated that the yield of CO is approximately 0.2 (g CO/g fuel consumed) and that this value is 

not very dependent on the combustible.9

 In this study, the post-flashover CO yields from the 

cable fires approach this, with a mean of ca. 0.15 g/g. The sofas and bookcases appear to 

generate about one quarter of the expected value. 

85
A first consideration is whether the tests truly reached flashover. Examination of the test videos 

and data logs indicate that each “declaration of flashover” occurred when key characteristics 

were observed: significant oxygen depletion within the fire room, high temperature in the upper 

layer of the burn room and in the upper portion of the doorway, flames out the doorway. 

Experimental errors of a sufficient magnitude are highly unlikely. Since two different types of 

analyzers with independent sampling lines produced comparable CO yields, the difference from

the expected value cannot be attributed to an instrumental or sampling error. Since the same

calculations produced CO2 yields near the notional limits, there cannot be a missing factor in the 

data reduction. 

It is possible that a large amount of CO is formed in the room, but is oxidized in the secondary 

burning at the doorway. Computer simulations of room fires using FDS indicate that the 

environment at Location 1 should be highly vitiated and that the CO should be at its peak there. 

The test records indicate low oxygen levels. However, Table 26 shows that the fraction of fuel 

carbon appearing in CO is actually lower at Location 1 than at Location 2. It is possible that at 

Location 1, a sizable fraction of the carbon exists as uncombusted pyrolyzate, some of which is 

partially oxidized to CO in the doorway. This would account for the observations of relative CO 

concentration in the two locations. However, this is speculative and at present, there is no firm

explanation for this behavior. 

A more likely hypothesis is as follows. Large quantities of pyrolyzate are generated during 

flashover. Much of these consume the limited available oxygen, forming CO, but leaving much 

of the organic matter unoxidized. As these gases reach the doorway and begin to entrain fresh 

air, more of the organic matter is oxidized to CO. Some of the CO is also oxidized to CO2. 

Combined, these processes set up a dynamic situation where the observed [CO]/[CO2] ratio and 

the yield of CO depend on the degree of air-effluent mixing and the rate of cooling of the total 

flow. 

Different fires and different stages of those fires are likely to be accompanied by differing 

degrees of CO formation and burnout. Thus, we suggest that for fire hazard and risk 

assessments, one should use the CO yield value of 0.2 g CO per g fuel consumed. Bench-scale 

combustors typically used for generating toxic potency data generally do not have the potential 

for the secondary combustion processes described above. Thus, for assessing the accuracy of the 

data from such apparatus, it is also appropriate to use the CO yield value of 0.2 g CO per g fuel 

consumed. 

G. Use of the Results 

The yield data developed here are ready for use in determining whether and how to use a benchscale apparatus for generating toxic potency data of known accuracy. Generically, the following 

steps are suggested:

• Combust samples of these specimens in the bench-scale device under a range of 

combustion conditions appropriate for well-ventilated and underventilated fires. 

• Determine the degree to which agreement is reached with the yields measured here. 

86
• For the gases whose yields here were below the detection limits, determine whether the 

bench-scale results are consistent with these detection limits. 

• For CO, keep in mind that other studies have measured yields significantly larger than the 

values determined here and use the CO yield value of 0.2 g CO per g fuel consumed. 

• Appropriate weighting of the comparisons for individual gases can be derived using the 

equations in ISO/TS 13571. 

87
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88
VI. CONCLUSION 

It is important to be able to demonstrate how well a bench-scale toxic potency measurement 

apparatus reflects the effluent produced in real fires of the same combustible. This report 

documents the measurement of the yields of the prime toxicants (CO2, CO, HCl, HCN) and 

smoke from the combustion of three complex products (sofa cushions, bookcases, and power 

cable) in a room connected to a long corridor. There are results for both the pre-flashover and 

post-flashover stages of the fires, with additional post-flashover yield data on a PVC material. 

The repeatability of the yields values obtained here is sufficient for determination of whether a 

bench-scale apparatus is producing results that are similar to or different from the real-scale 

results here. 

The uncertainty in the post-flashover data is smaller due to the larger species concentrations and 

the more fully established upper layer from which the fire effluent was sampled. The toxicant 

yields from sofa cushion fires in a closed room were similar to those from pre-flashover fires of 

the same cushions in a room with the door open. 

Since a large fraction of fire deaths result from post-flashover fires and since CO is always a 

major (if not the dominant) incapacitating toxicant, the repeatability results indicate an

uncertainty in the fractional effective dose (FED) calculations that is comparable to the 

uncertainty in the equations themselves. The repeatability values should also be sufficient to 

determine whether a bench-scale apparatus is producing results that are similar to or different 

from the real-scale results here. 

Other toxicants (NO2, formaldehyde and acrolein) were not found. Concentrations below the 

detection limits were shown to be of limited toxicological importance relative to the detected 

toxicants. 

The use of Fourier transform infrared (FTIR) spectroscopy was shown to be a useful tool for 

obtaining toxicant concentration data. However, its operation and interpretation are far from

routine. The agreement between the FTIR instruments and conventional non-dispersive infrared 

analyzers was not perfect but was reasonable enough to identify situations where the effluent 

sampling may have been compromised and where signals were approaching the background 

limits. 

Measurements at both ends of the corridor provided an indication of the degree to which the 

combustion product concentrations decreased relative to simple dilution. The losses of CO, 

HCN, and HCl were found to be dependent on the combustible. The downstream to upstream

concentration ratios varied from unity for some fuels to a factor of five smaller for others. 

The yield of CO for the sofa and bookcase tests was significantly lower than the expected value 

of 0.2, while the CO yield for the cable tests was close. The determinations were shown to be 

accurate. It is suggested that one should use the CO yield value of 0.2 g CO per g fuel consumed 

for both fire safety analyses and for assessing the accuracy of bench-scale combustors for 

generating toxic potency data 

89
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90
VII. ACKNOWLEDGMENTS 

The authors express their appreciation for the contributions of many people in bringing success 

to such an expansive project. George Mulholland designed the smoke sampling apparatus, 

which was built and operated by Michael Selepak; Dr. Mulholland and Jenny Oran analyzed the 

data. David Stroup operated the large-scale test facility and with Lauren DeLauter and Gary 

Roadarmel built the room/corridor assembly and assisted in the tests. Richard Harris designed 

the wet chemistry apparatus and applied it to many of the tests, assisted by Walid Awad. Jack 

Lee assisted in numerous ways during the room construction and test conduct. Jonathan 

Demarest also assisted with the tests and in reducing the data. Dr. Kurt Reimann of BASF 

provided information helpful in the design of the sofas; Douglas Wetzig of PolyOne supplied the 

PVC sheet; David Mercier of Southwire, Inc. provided useful information on the formulation of 

the cable. Schwartzkopf Laboratories performed the elemental and thermal analyses of the 

combustibles. 

The research was co-sponsored by the Alliance for the Polyurethane Industry, the American 

Plastics Council, DuPont, Lamson & Sessions, Underwriters Laboratories, and the Vinyl 

Institute under the aegis of the Fire Protection Research Foundation and the supervision of 

Frederick Mulhaupt and Steven Hanly. 

91
APPENDIX A. GRAPHS OF TEST DATA 

Figures A1a, A1b Data from Test SW1, Location 2 ...................................94 

Figures A1c, A1d Data from Test SW1, Location 4 ...................................95 

Figures A2a, A2b Data from Test SW2, Location 2 ...................................96 

Figures A2c, A2d Data from Test SW2, Location 4 ...................................97 

Figures A3a, A3b Data from Test SW3, Location 2 ...................................98 

Figures A3c, A3d Data from Test SW3, Location 4 ...................................99 

Figures A4a, A4b Data from Test SW10, Location 2 ...............................100 

Figures A4c, A4b Data from Test SW10, Location 4 ...............................101 

Figures A5a, A5b Data from Test SW11, Location 2 ...............................102 

Figures A5c, A5d Data from Test SW11, Location 4 ...............................103 

Figures A6a, A6b Data from Test SW12, Location 2 ...............................104 

Figures A6c, A6d Data from Test SW12, Location 4 ...............................105 

Figures A7a, A7b Data from Test SW13, Location 2 ...............................106 

Figures A7c, A7d Data from Test SW13, Location 4 ...............................107 

Figures A8a, A8b Data from Test SW14, Location 2 ...............................108 

Figures A8c, A8d Data from Test SW14, Location 4 ...............................109 

Figures A9a, A9b Data from Test BW1, Location 2 .................................110 

Figures A10a, A10b Data from Test BW2, Location 2 .................................111 

Figures A10c, A10d Data from Test BW2, Location 4 .................................112 

Figures A11a, A11b Data from Test BW3, Location 2 .................................113 

Figures A11c, A11d Data from Test BW3, Location 4 .................................114 

Figures A12a, A12b Data from Test BW4, Location 2 .................................115 

Figures A12c, A12d Data from Test BW4, Location 4 .................................116 

Figures A13a, A13b Data from Test BW5, Location 2 .................................117 

Figures A13c, A13d Data from Test BW5, Location 4 .................................118 

Figures A14a, A14b Data from Test BW6, Location 2 .................................119 

Figures A14c, A14d Data from Test BW6, Location 4 .................................120 

Figures A15a, A15b Data from Test BW7, Location 2 .................................121 

Figures A15c, A15d Data from Test BW7, Location 4 .................................122 

Figures A16a, A16b Data from Test BP1, Location 2 ..................................123 

92
Figures A16c, A16d Data from Test BP1, Location 4 ..................................124 

Figures A17a, A17b Data from Test BP2, Location 2 ..................................125 

Figures A17c, A17d Data from Test BP2, Location 4 ..................................126 

Figures A18a, A18b Data from Test BP3, Location 2 ..................................127 

Figures A18c, A18d Data from Test BP3, Location 4 ..................................128 

Figures A24a, A24b Data from Test SC2, Location 1 ..................................136 

Figures A19a, A19b Data from Test PQ1, Location 2 ..................................129 

Figures A20a, A20b Data from Test PQ2, Location 2 ..................................130 

Figures A21a, A21b Data from Test PW1, Location 2 .................................131 

Figures A21c, A21d Data from Test PW1, Location 4 .................................132 

Figures A22a, A22b Data from Test PW2, Location 2 .................................133 

Figures A22c, A22d Data from Test PW2, Location 4 .................................134 

Figures A23a, A23b Data from Test SC1, Location 1 ..................................135 

93
Figures A1a, A1b. Data from Test SW1, Location 2 

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

0 100 200 300 400 500 600

Time (s)

Volume Fraction

CO x 100 (FTIR) CO2 (FTIR) CO x 100 (NDIR) CO2 (NDIR)

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0.005

0.01

0.015

0.02

0.025

0.03

0.035

0.04

0 100 200 300 400 500 600

Time (s)

Volume Fraction

0

0.005

0.01

0.015

0.02

0.025

0.03

0.035

0.04

Mass Loss Rate (kg/s)

HCl (FTIR) HCN (FTIR) Mass Loss Rate

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Figures A1c, A1d. Data from Test SW1, Location 4 

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0 100 200 300 400 500 600

Time (s)

Volume Fraction

CO x 100 (FTIR) CO2 (FTIR) CO x 100 (NDIR) CO2 (NDIR)

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0.00005

0.0001

0.00015

0.0002

0.00025

0.0003

0.00035

0 100 200 300 400 500 600

Time (s)

Volume Fraction

HCl (FTIR) HCN x 10 (FTIR)

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Figures A2a, A2b. Data from Test SW2, Location 2 

0

0.01

0.02

0.03

0.04

0.05

0 100 200 300 400 500

Time (s)

Volume Fraction

CO x 100 (FTIR) CO2 (FTIR) CO x 100 (NDIR) CO2 (NDIR)

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0.001

0.002

0.003

0.004

0.005

0.006

0 100 200 300 400 500 600 700 800

Time (s)

Volume Fraction

0

0.005

0.01

0.015

0.02

0.025

0.03

0.035

Mass Loss Rate (kg/s)

HCl x 10 (FTIR) HCN x 10 (FTIR) O2 x 0.01 Mass Loss Rate

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96
Figures A2c, A2d. Data from Test SW2, Location 4 

 

0

0.005

0.01

0.015

0.02

0.025

0.03

0.035

0.04

0.045

0.05

0 100 200 300 400 500

Time (s)

Volume Fraction

CO x 100 (FTIR) CO2 (FTIR) CO x 100 (NDIR) CO2 (NDIR)

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0

0.00001

0.00002

0.00003

0.00004

0.00005

0.00006

0.00007

0.00008

0.00009

0.0001

0 100 200 300 400 500

Time (s)

Volume Fraction

HCl (FTIR) HCN (FTIR) O2 x 0.0001

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97
98

Figures A3a, A3b. Data from Test SW3, Location 2 

 

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

50 100 150 200 250 300 350 400 450

Time (s)

Volume Fraction

CO x 10 (FTIR) CO2 (FTIR) CO x 10 (NDIR) CO2 (NDIR)

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0.001

0.002

0.003

0.004

0.005

0.006

0.007

0.008

0.009

0.01

0 50 100 150 200 250 300 350 400 450

Time (s)

Volume Fraction

0

0.005

0.01

0.015

0.02

0.025

0.03

0.035

0.04

0.045

Mass Loss Rate (kg/s)

HCl x 10 (FTIR) HCN x 10 (FTIR) O2 x 0.01 Mass Loss Rate

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Figures A3c, A3d. Data from Test SW3, Location 4 

0

0.01

0.02

0.03

0.04

0.05

0.06

0 50 100 150 200 250 300 350 400 450

Time (s)

Volume Fraction

CO x 100 (FTIR) CO2 (FTIR) CO x 10 (NDIR) CO2 (NDIR)

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0.000002

0.000004

0.000006

0.000008

0.00001

0.000012

0 50 100 150 200 250 300 350 400 450

Time (s)

Volume Fraction

HCl (FTIR) HCN (FTIR) O2 x 0.00001

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99
Figures A4a, A4b. Data from Test SW10, Location 2 

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

0.1

0 50 100 150 200 250 300 350 400

Time (s)

Volume Fraction

CO x 10 (FTIR) CO2 (FTIR) CO x 10 (NDIR) CO2 (NDIR)

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0.005

0.01

0.015

0.02

0.025

0.03

0 50 100 150 200 250 300 350 400

Time (s)

Volume Fraction

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

Mass Loss Rate (kg/s)

HCl x 10 (FTIR) HCN x 10 (FTIR) O2 x 0.001 Mass Loss Rate

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Figures A4c, A4d. Data from Test SW10, Location 4 

 

0

0.01

0.02

0.03

0.04

0.05

0.06

0 50 100 150 200 250 300 350 400

Time (s)

Volume Fraction

CO x 10 (FTIR) CO2 (FTIR) CO x 10 (NDIR) CO2 (NDIR)

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0.0001

0.0002

0.0003

0.0004

0.0005

0.0006

0.0007

0 50 100 150 200 250 300 350 400

Time (s)

Volume Fraction

HCl (FTIR) HCN (FTIR) O2 x 0.001

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101
Figures A5a, A5b. Data from Test SW11, Location 2 

 

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

0 50 100 150 200 250 300

Time (s)

Volume Fraction

CO x 10 (FTIR) CO2 (FTIR) CO x 10 (NDIR) CO2 (NDIR)

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0.0005

0.001

0.0015

0.002

0.0025

0 50 100 150 200 250 300

Time (s)

Volume Fraction

-0.08

-0.06

-0.04

-0.02

0

0.02

0.04

0.06

0.08

0.1

Mass Loss Rate (kg/s)

HCl (FTIR) HCN (FTIR) O2 x 0.001 Mass Loss Rate

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102
Figures A5c, A5d. Data from Test SW11, Location 4 

 

0

0.01

0.02

0.03

0.04

0.05

0.06

0 50 100 150 200 250 300 350

Time (s)

Volume Fraction

CO x 100 (FTIR) CO2 (FTIR) CO x 10 (NDIR) CO2 (NDIR)

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0.00005

0.0001

0.00015

0.0002

0.00025

0 50 100 150 200 250 300 350

Time (s)

Volume Fraction

HCl (FTIR) HCN (FTIR) O2 x 0.001

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103
Figures A6a, A6b. Data from Test SW12, Location 2 

 

0

0.02

0.04

0.06

0.08

0.1

0.12

50 100 150 200 250 300 350

Time (s)

Volume Fraction

CO x 10 (FTIR) CO2 (FTIR) CO x 10 (NDIR) CO2 (NDIR)

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0.14

0

0.0005

0.001

0.0015

0.002

0.0025

50 100 150 200 250 300 350

Time (s)

Volume Fraction

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

Mass Loss Rate (kg/s)

HCl (FTIR) HCN (FTIR) O2 x 0.001 Mass Loss Rate

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Figures A6c, A6d. Data from Test SW12, Location 4 

0

0.01

0.02

0.03

0.04

0.05

0.06

0 50 100 150 200 250 300 350 400

Time (s)

Volume Fraction

CO x 10 (FTIR) CO2 (FTIR) CO x 10 (NDIR) CO2 (NDIR)

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0.00005

0.0001

0.00015

0.0002

0.00025

0 50 100 150 200 250 300 350 400

Time (s)

Volume Fraction

HCl (FTIR) HCN (FTIR) O2 x 0.001

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105
106

0

0.0005

0.001

0.0015

0.002

0 50 100 150 200 250 300 350 400 450

Time (s)

Volume Fraction

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

Mass Loss Rate (kg/s)

HCl (FTIR) HCN (FTIR) O2 x 0.001 Mass Loss Rate

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Figures A7a, A7b. Data from Test SW13, Location 2 

0

0.02

0.04

0.06

0.08

0.1

0.12

0 50 100 150 200 250 300 350 400 450

Time (s)

Volume Fraction

CO x 10 (FTIR) CO2 (FTIR) CO x 10 (NDIR) CO2 (NDIR)

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Figures A7c, A7d. Data from Test SW13, Location 4 

 

0

0.01

0.02

0.03

0.04

0.05

0.06

0 100 200 300 400 500

Time (s)

Volume Fraction

CO x 10 (FTIR) CO2 (FTIR) CO x 10 (NDIR) CO2 (NDIR)

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0.0001

0.0002

0.0003

0.0004

0.0005

0.0006

0 100 200 300 400 500

Time (s)

Volume Fraction

HCl (FTIR) HCN (FTIR) O2 x 0.001

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107
Figures A8a, A8b. Data from Test SW14, Location 2 

 

0

0.0005

0.001

0.0015

0.002

0.0025

100 150 200 250 300 350 400 450 500

Time (s)

Mole Fraction

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

Mass Loss Rate (kg/s)

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HCl (FTIR) HCN (FTIR) O2 x 0.001 Mass Loss Rate

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0.16

100 150 200 250 300 350 400 450 500

Time (s)

Volume Fraction

CO x 10 (FTIR) CO2 (FTIR) CO x 10 (NDIR) CO2 (NDIR)

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109

Figures A8c, A8d. Data from Test SW14, Location 4 

 

0

0.01

0.02

0.03

0.04

0.05

0.06

0 100 200 300 400 500 600

Time (s)

Volume Fraction

CO x 10 (FTIR) CO2 (FTIR) CO x 10 (NDIR) CO2 (NDIR)

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0

0.00005

0.0001

0.00015

0.0002

0.00025

0.0003

0.00035

0.0004

0.00045

0.0005

0 100 200 300 400 500 600

Time (s)

Volume Fraction

HCl (FTIR) HCN (FTIR) O2 x 0.001 

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110

Figures A9a, A9b. Data from Test BW1, Location 2 

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0.16

0.18

0 50 100 150 200 250 300 350 400 450

Time (s)

Volume Fraction

CO x 10 (NDIR) CO2 (NDIR)

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0.05

0.1

0.15

0.2

0.25

0.3

0 50 100 150 200 250 300 350 400 450

Time (s)

Mass Loss Rate (kg/s)

Mass Loss Rate

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Figures A10a, A10b. Data from Test BW2, Location 2

 

0

0.0002

0.0004

0.0006

0.0008

0.001

0.0012

0.0014

0.0016

0.0018

0 200 400 600 800 1000 1200 1400 1600

Time (s)

Volume Fraction

CO x 10 (NDIR) CO2 (NDIR)

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0.00000

0.00200

0.00400

0.00600

0.00800

0.01000

0.01200

0 200 400 600 800 1000 1200 1400 1600

Time (s)

Volume Fraction

O2 x 0.01 Mass Loss Rate

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111
Figures A10c, A10d. Data from Test BW2, Location 4 

0

0.005

0.01

0.015

0.02

0.025

0 200 400 600 800 1000 1200 1400 1600

Time (s)

Volume Fraction

CO x 100 (NDIR) CO2 (NDIR)

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0

0.05

0.1

0.15

0.2

0.25

0 200 400 600 800 1000 1200 1400 1600

Time (s)

Volume Fraction

O2

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112
113

Figures A11a, A11b. Data from Test BW3, Location 2 

 

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0 200 400 600 800 1000 1200

Time (s)

Mole Fraction

CO x 10 (NDIR) CO2 (NDIR)

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0

0.05

0.1

0.15

0.2

0.25

0 200 400 600 800 1000 1200

Time (s)

Mole Fraction

-0.04

-0.02

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

Mass Loss Rate (kg/s)

O2 Mass Loss Rate

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Figures A11c, A11d. Data from Test BW3, Location 4 

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

0 200 400 600 800 1000 1200

Time (s)

Volume Fraction

CO x 10 (NDIR) CO2 (NDIR)

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0

0.05

0.1

0.15

0.2

0.25

0 200 400 600 800 1000 1200

Time (s)

Volume Fraction

O2

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114
Figures A12a, A12b. Data from Test BW4, Location 2 

 

0

0.05

0.1

0.15

0.2

0.25

0.3

250 300 350 400 450 500

Time (s)

Volume Fraction

CO x 100 (FTIR) CO2 (FTIR) CO x 10 (NDIR) CO2 (NDIR)

P

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0

0.05

0.1

0.15

0.2

0.25

0 200 400 600 800 1000 1200

Time (s)

Volume Fraction

-0.04

-0.02

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

Mass Loss Rate (kg/s)

HCl (FTIR) HCN x 1000 (FTIR) O2 Mass Loss Rate

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115
Figures A12c, A12d. Data from Test BW4, Location 4 

 

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0 200 400 600 800 1000 1200

Time (s)

Volume Fraction

CO x 10 (FTIR) CO2 (FTIR) CO x 10 (NDIR) CO2 (NDIR)

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0

0.00005

0.0001

0.00015

0.0002

0.00025

0 200 400 600 800 1000

Time (s)

Volume Fraction

HCl (FTIR) HCN (FTIR) O2 x 0.0001

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116
117

Figures A13a, A13b. Data from Test BW5, Location 2 

0

0.0002

0.0004

0.0006

0.0008

0.001

0.0012

0.0014

0.0016

0.0018

0.002

0 100 200 300 400 500 600 700 800 900

Time (s)

Volume Fraction

CO x 10 (NDIR) CO2 (NDIR)

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0.25 0.0045

0

0.05

0.1

0.15

0.2

0 100 200 300 400 500 600 700 800 900

Time (s)

Volume Fraction

0

0.0005

0.001

0.0015

0.002

0.0025

0.003

0.0035

0.004

Mass Loss Rate (kg/s)

O2 Mass Loss Rate

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Figures A13c, A13d. Data from Test BW5, Location 4 

0

0.0005

0.001

0.0015

0.002

0.0025

0.003

0.0035

0.004

0.0045

0 100 200 300 400 500 600 700 800 900

Time (s)

Volume Fraction

CO x 10 (NDIR) CO2 (NDIR)

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0

0.05

0.1

0.15

0.2

0.25

0 100 200 300 400 500 600 700 800 900

Time (s)

Volume Fraction

O2

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118
Figures A14a, A14b. Data from Test BW6, Location 2 

119

 

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

200 300 400 500 600 700 800 900 1000

Time (s)

Volume Fraction

CO x 10 (NDIR) CO2 (NDIR)

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0.25 0.2

0

0.05

0.1

0.15

0.2

0 200 400 600 800 1000

Time (s)

Volume Fraction

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0.16

0.18

Mass Loss Rate (kg/s)

O2 Mass Loss Rate

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Figures A14c, A14d. Data from Test BW6, Location 4 

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

0.1

0 200 400 600 800 1000

Time (s)

Volume Fraction

CO x 10 (NDIR) CO2 (NDIR)

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0

0.05

0.1

0.15

0.2

0.25

200 300 400 500 600 700 800 900 1000

Time (s)

Volume Fraction

O2

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120
Figures A15a, A15b. Data from Test BW7, Location 2 

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0 100 200 300 400 500 600 700 800 900 1000

Time (s)

Volume Fraction

CO x 10 (FTIR) CO2 (FTIR) CO x 10 (NDIR) CO2 (NDIR)

P

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0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

0.4

0.45

0.5

0 200 400 600 800 1000

Time (s)

Volume Fraction

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

Mass Loss Rate (kg/s)

HCl x 1000 (FTIR) HCN x 1000 (FTIR) O2 Mass Loss Rate

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121
Figures A15c, A15d. Data from Test BW7, Location 4 

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0 200 400 600 800 1000 1200

Time (s)

Volume Fraction

CO x 100 (FTIR) CO2 (FTIR) CO x 10 (NDIR) CO2 (NDIR)

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0

0.000005

0.00001

0.000015

0.00002

0 200 400 600 800 1000 1200

Time (s)

HCl (FTIR) HCN (FTIR) O2 x 0.0001

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0.000025

Volume Fraction

122
Figures A16a, A16b. Data from Test BP1, Location 2 

 

0.2

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0.16

0.18

200 250 300 350 400 450 500

Time (s)

Volume Fraction

CO x 10 (FTIR) CO2 (FTIR) CO x 10 (NDIR) CO2 (NDIR)

P

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0

0.0005

0.001

0.0015

0.002

0 100 200 300 400 500

Time (s)

Volume Fraction

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0.16

0.18

Mass Loss Rate (kg/s)

HCl x 0.1 (FTIR) HCN (FTIR) O2 x 0.001 PVC Mass Loss Rate Bookcase Mass Loss Rate

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123
124

Figures A16c, A16d. Data from Test BP1, Location 4

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0.16

0.18

0 100 200 300 400 500 600 700 800

Time (s)

Volume Fraction

CO x 10 (FTIR) CO2 (FTIR) CO x 10 (NDIR) CO2 (NDIR)

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0

0.00005

0.0001

0.00015

0.0002

0.00025

0.0003

0 100 200 300 400 500 600 700 800

Time (s)

Volume Fraction

HCl x 0.1 (FTIR) HCN (FTIR) O2 x 0.001

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Figures A17a, A17b. Data from Test BP2, Location 2

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0.16

0 200 400 600 800 1000 1200 1400 1600

Time (s)

Volume Fraction

CO x 10 (FTIR) CO2 (FTIR) CO x 10 (NDIR) CO2 (NDIR)

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0

0.0005

0.001

0.0015

0.002

0.0025

0 200 400 600 800 1000 1200 1400 1600

Time (s)

Volume Fraction

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

Mass Loss Rate (kg/s)

HCl x 0.1 (FTIR) HCN (FTIR) O2 x 0.001 PVC Mass Loss Bookcase Mass Loss

P

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125
Figures A17c, A17d. Data from Test BP2, Location 4 

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0 200 400 600 800 1000 1200 1400 1600

Time (s)

Volume Fraction

CO x 10 (FTIR) CO2 (FTIR) CO x 10 (NDIR) CO2 (NDIR)

P

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r

0

0.00005

0.0001

0.00015

0.0002

0.00025

0 200 400 600 800 1000 1200 1400 1600

Time (s)

Volume Fraction

HCl x 0.1 (FTIR) HCN (FTIR) O2 x 0.001

P

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126
Figures A18a, A18b. Data from Test BP3, Location 2 

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0.16

0.18

0.2

200 250 300 350 400 450 500 550 600

Time (s)

Volume Fraction

CO x 10 (FTIR) CO2 (FTIR) CO x 10 (NDIR) CO2 (NDIR)

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0.002 0.25

0

0.0002

0.0004

0.0006

0.0008

0.001

0.0012

0.0014

0.0016

0.0018

0 100 200 300 400 500 600

Time (s)

Volume Fraction

0

0.05

0.1

0.15

0.2

Mass Loss Rate (kg/s)

HCl x 0.1 (FTIR) HCN (FTIR) O2 x 0.001 Mass Loss Rate

P

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127
128

Figures A18c, A18d. Data from Test BP3, Location 4 

0

0.02

0.04

0.06

0.08

0.1

0.12

0 100 200 300 400 500 600

Time (s)

Volume Fraction

CO x 100 (FTIR) CO2 (FTIR) CO x 10 (NDIR) CO2 (NDIR)

P

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0

0.0005

0.001

0.0015

0.002

0.0025

0.003

0.0035

0.004

0 100 200 300 400 500 600

Time (s)

Volume Fraction

HCl (FTIR) HCN x 10 (FTIR) O2 x 0.01

P

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Figures A19a, A19b. Data from Test PQ1, Location 2 

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0.16

0.18

0.2

0 50 100 150 200 250 300 350 400 450

Time (s)

Volume Fraction

CO x 10 (FTIR) CO2 (FTIR) CO x 10 (NDIR) CO2 (NDIR)

P

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0

0.005

0.01

0.015

0.02

0.025

0 50 100 150 200 250 300 350 400 450

Time (s)

Volume Fraction

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

0.1

Mass Loss Rate (kg/s)

HCl (FTIR) HCN x 10 (FTIR) O2 x 0.1 Mass Loss Rate

P

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129
130

Figures A20a, A20b. Data from Test PQ2, Location 2

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0.16

0.18

0 100 200 300 400 500 600 700 800

Time (s)

Volume Fraction

CO x 10 (FTIR) CO2 (FTIR) CO x 10 (NDIR) CO2 (NDIR)

P

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0

0.002

0.004

0.006

0.008

0.01

0.012

0.014

0.016

0.018

0.02

0 100 200 300 400 500 600 700 800

Time (s)

Volume Fraction

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

HCl (FTIR) HCN x 10 (FTIR) O2 x 0.01 Mass Loss Rate

P

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Figures A21a, A21b. Data from Test PW1, Location 2

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0.16

0.18

0 100 200 300 400 500 600 700

Time (s)

Volume Fraction

CO x 10 (FTIR) CO2 (FTIR) CO x 10 (NDIR) CO2 (NDIR)

P

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r

0

0.002

0.004

0.006

0.008

0.01

0.012

0.014

0.016

0.018

0 100 200 300 400 500 600 700

Time (s)

Volume Fraction

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

0.1

Mass Loss Rate (kg/s)

HCl (FTIR) HCN x 10 (FTIR) O2 x 0.01 Mass Loss Rate

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131
Figures A21c, A21d. Data from Test PW1, Location 4 

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

0 100 200 300 400 500 600 700

Time (s)

Volume Fraction

CO x 10 (FTIR) CO2 (FTIR) CO x 10 (NDIR) CO2 (NDIR)

P

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0

0.0005

0.001

0.0015

0.002

0.0025

0.003

0.0035

0 100 200 300 400 500 600 700

Time (s)

Volume Fraction

HCl (FTIR) HCN (FTIR) O2 x 0.001

P

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132
133

Figures A22a, A22b. Data from Test PW2, Location 2 

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0.16

0.18

0 200 400 600 800 1000

Time (s)

Volume Fraction

CO x 10 (FTIR) CO2 (FTIR) CO x 10 (NDIR) CO2 (NDIR)

P

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0

0.0002

0.0004

0.0006

0.0008

0.001

0.0012

0.0014

0.0016

0.0018

0.002

0 200 400 600 800 1000

Time (s)

Volume Fraction

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

Mass Loss Rate (kg/s)

HCl x 0.1 (FTIR) HCN (FTIR) O2 x 0.001 Mass Loss Rate

P

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134

Figures A22c, A22d. Data from Test PW2, Location 4 

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

0 200 400 600 800 1000

Time (s)

Volume Fraction

CO x 10 (FTIR) CO2 (FTIR) CO x 10 (NDIR) CO2 (NDIR)

P

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r

0

0.00005

0.0001

0.00015

0.0002

0.00025

0.0003

0.00035

0.0004

0 200 400 600 800 1000

Time (s)

Volume Fraction

HCl x 0.1 (FTIR) HCN (FTIR) O2 x 0.001

P

r

e

f

l

a

s

h

o

v

e

r

P

o

s

t

f

l

a

s

h

o

v

e

r
135

Figures A23a, A23b. Data from Test SC1, Location 1 

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

0.1

0 100 200 300 400 500

Time (s)

Volume Fraction

CO (FTIR) CO2 (FTIR) CO x 10 (NDIR) CO2 (NDIR)

P

r

e

f

l

a

s

h

o

v

e

r

0

0.000005

0.00001

0.000015

0.00002

0.000025

0 100 200 300 400 500

Time

Volume Fraction

0

0.001

0.002

0.003

0.004

0.005

0.006

0.007

0.008

0.009

Mass Loss Rate (kg/s)

HCl x 10 (FTIR) HCN (FTIR) O2 x 0.0001 Mass Loss Rate

P

r

e

f

l

a

s

h

o

v

e

r
Figures A24a, A24b. Data from Test SC2, Location 1

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

0 100 200 300 400 500 600 700

Time (s)

Volume Fraction

CO x 10 (FTIR) CO2 (FTIR) CO x 10 (NDIR) CO2 (NDIR)

P

r

e

f

l

a

s

h

o

v

e

r

0

0.000005

0.00001

0.000015

0.00002

0.000025

0 100 200 300 400 500 600

Time (s)

Volume Fraction

0

0.001

0.002

0.003

0.004

0.005

0.006

0.007

0.008

Mass Loss Rate (kg/s)

HCl (FTIR) HCN (FTIR) O2-4 x 0.0001 Mass Loss Rate

136
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139