NBSIR 77-1225

Test and Evaluation of the

Smoke Control Capabilities of

the San Diego Veterans

Administration Hospital

Francis C. W. Fung and Richard H. Zile

Center for Fire Research

Institute for Applied Technology

National Bureau of Standards

Washington, D.C. 20234

April 1977

Final Report

Prepared for Office of Construction

Veterans Administration

Washington, D.C. 20420

NBSIR 77-1225

TEST AND EVALUATION OF THE

SMOKE CONTROL CAPABILITIES OF

THE SAN DIEGO VETERANS

ADMINISTRATION HOSPITAL

Francis C. W. Fung and Richard H. Zile

Center for Fire Research

Institute for Applied Technology

National Bureau of Standards

Washington, D.C. 20234

April 1977

Final Report

Prepared for Office of Construction

Veterans Administration

Washington, D.C. 20420

U.S. DEPARTMENT OF COMMERCE, Juanita M. Kreps, Secretary

Dr. Sidney Harman, Under Secretary

Jordan J. Baruch. Assistant Secretary for Science and Technology

NATIONAL BUREAU OF STANDARDS, Ernest Ambler, Acting Director
: 3; ;

.

:• • V, ,,,

<

. ? v
CONTENTS

Page

LIST OF FIGURES iv

LIST OF TABLES v

Abstract 1

1. INTRODUCTION 2

2. TEST METHODS 4

2.1. Smoke Simulation Experiments 4

2.2. Pressure Monitor Experiments 5

3. RESULTS AND DISCUSSION 5

3.1. Smoke Simulation Experiments 5 3.2. Pressure Monitor Experiments 7 3.3. Computer Analysis of Smoke Movement 9

3.3.1. Computer Program 9

3.3.2. The Assumptions 9

3.3.3. Building Configuration Properties 10

3.3.4. Field Trip Comparisons and Parametric Studies 12

3.3.5. Computer Simulation of the San Diego VA

Hospital 13

4. CONCLUSIONS 13

5. REFERENCES 14

APPENDIX A. DESCRIPTION OF AIR-HANDLING SYSTEM 38

APPENDIX B. PRESSURE FORCE DUE TO STACK EFFECT 39

APPENDIX C. PRESSURE FORCE DUE TO WIND EFFECT 41

APPENDIX D. FIELD TEST COMPARISON AND PARAMETRIC ANALYSIS

SAN DIEGO VETERANS ADMINISTRATION HOSPITAL. ... 43

iii
LIST OF FIGURES

Page

Figure 1. Elevation of San Diego VA Hospital 25

Figure 2. San Diego VA Hospital Typical Floor Plan 26

Figure 3. Third Floor, Floor Plan 27

Figure 4. Second Floor, Floor Plan 28

Figure 5. Sampling Locations for Smoke Test 29

Figure 6. Sampling Locations for Pressure Monitor Experiments . 30

Figure 7. San Diego VAH, Horizontal Smoke Movement Experiment

[Test 1] 31

Figure 8. San Diego VAH, Vertical Smoke Movement Experiment

[Tests 3 and 4] 32

Figure 9. Third Floor SF 6 Decay Study, Location 3-1 [Test 5] . . 33

Figure 10. Stack Effect versus Building Height for Different

Outside Temperatures 34

Figure 11. San Diego VAH Elevator Shaft Pressure Profile, Smoke

Control Mode [Test 4] . . .• 35

Figure 12. San Diego VAH Center Core Pressure Profile, Smoke

Control Mode [Test 2] 36

Figure 13. Pressure versus Velocity Head 37
LIST OF TABLES

Page

Table 1. San Diego Pressure Test Configurations 16

Table 2. Third Floor Smoke Simulation with HVAC in Normal Mode. 17

Table 3. Third Floor Smoke Simulation with HVAC in Control Mode 18

Table 4. Second Floor Smoke Simulation with HVAC in Normal Mode 19

Table 5. Second Floor Smoke Simulation with HVAC in Control

Mode 20

Table 6. Third Floor SFg Decay Study 21

Table 7. Third Floor Interstitial Space SF 6 Purging Study ... 22

Table 8. Temperature and Wind Conditions 23

Table 9. Pressure Difference Across Doors 24

v
'

.

: -•

,

'

. :

.

'

.
TEST AND EVALUATION OF THE SMOKE CONTROL CAPABILITIES OF THE

SAN DIEGO VETERANS ADMINISTRATION HOSPITAL

Francis C. W. Fung and Richard H. Zile

Abstract

A study was made by the National Bureau of Standards to

evaluate the smoke control capabilities of the San Diego

Veterans Administration Hospital. A unique feature of the

hospital is the presence of independent air-handling units

for each floor and each wing. This feature allows the airhandling units to be manipulated for smoke control following

the systematic pressurization concept. Systematic pressurization is a means of smoke control whereby a building is

divided into either vertical or horizontal compartmented

zones such that the air-handling systems are designed to

exhaust the immediate fire zone and pressurize the adjacent

surrounding zones upon detection of smoke. An experimental

technique of smoke simulation and smoke movement measurement

was used for the study. The effectiveness of the systematic

pressurization smoke control concept is demonstrated by the

simulated smoke concentration profiles and pressure measurements .

An extensive series of experiments designed to evaluate

the above smoke control concepts were performed by the NBS in

cooperation with the VA. Two types of experiments were performed with the building air-handling system operating in

normal and various smoke control modes. First, simulated

smoke infiltration measurements were obtained by using the

sulfur-hexafluoride smoke simulation technique. Second,

pressure measurements were obtained across elevator doors,

and doors leading from the building central core to each wing.

Both SFg concentrations and pressure measurements are key

indicators of smoke movement in this evaluation. Six basic

air-handling test configurations were established and pressure

difference data was collected at fifteen locations on each

floor measured. At least two floors and more generally three

floors were measured for each mode. Each of the six configurations tested are summarized in table 7, and the measured

data are summarized in table 8. A total of six smoke simulation experiments were conducted. The results and test con- ditions for each test are tabulated in tables 1 to 6 inclusively. It is concluded that air-handling systems in the

San Diego VA Hospital can be effective in controlling smoke

movement if the proper vertical and horizontal systematic pressurization concept as described in this report is applied.

This is illustrated in figures 7, 8, 11, and 12.

1
A computer smoke movement simulation analysis is also

presented. Computer calculations compared favorably with

field data. Parametric analysis was also performed on smoke

control modes for varying environmental and leakage conditions

to further study the smoke control uses of the air-handling

system and to demonstrate the capability of the computer

simulation program.

Key words: Air-handling units; building pressure profile;

computer simulation; elevator shaft pressure profiles; parametric analysis; simulated smoke concentration; smoke control;

smoke movement; smoke simulation; systematic pressurization.

1 . INTRODUCTION

In a high-rise building where total evacuation time from a building

is excessive, or when evacuation is impractical or impossible, such as

in a health care facility, a system is needed to provide for smoke-free

travel routes to an area of refuge and to maintain refuge areas free

from the migration of smoke. The system for control of smoke is needed

primarily for occupant protection, although it could very well aid the

firefighter. It is recommended that smoke control systems not be merely

passive systems, such as those involving simple closing of dampers, or the automatic shut-down of air-handling system fans upon the detection

of smoke in the return air system. What is needed are active systems to

overcome the natural fluid motion of smoke in tall buildings where the

air is buoyant and expanding at elevated fire temperatures, where the

air is subject to movement due to conditions external to the building,

such as stack effect and wind conditions.

Fluid motion in general, including air or smoke, is caused by the

action of natural and mechanical forces. In a fire the two motivation

forces that cause smoke movement are the buoyancy forces and the pressure

forces. Buoyancy forces in a fire are caused by density changes in air

due to heating. The relative difference in density then sets up a con- vective flow in a gravitational field. Pressure forces can originate in

a number of ways, e.g., (1) by restriction of volume expansion, (2) by

the exterior- interior temperature differences, (3) by the effect of wind

velocity and direction, and (4) by the pressure differences maintained

by the air-handling systems. For example, the well known stack effect

in a high-rise building [1-5]^ is caused by the difference in hydrostatic

pressure due to two air columns (one inside the building and the other

outside) at different temperatures. For a detailed discussion of these

forces, including derivation of formulas from basic principles and a comparison of the order of magnitudes, one may refer to reference [6].

Various forms of stairwell, core, and corridor mechanical pressurization and exhaust schemes have appeared in the last couple of years [6-

18]

Bracketed numbers refer to the references listed in Section 5 at the

end of this paper. 2
The purpose of these systems is twofold: (1) to vent, or exhaust the

fire area of smoke and (2) to pressurize adjacent and remote areas of

the building to prevent smoke migration to and through the various exit

travel routes (such as corridors, stairs and elevator shafts) and to the

various refuge areas designated throughout a tall building. These

systems need to overcome the various buoyancy forces and volume outflow

from a fire, as well as external forces such as stack action and wind.

Mechanical methods of smoke control, such as the use of the building’s air-handling system and the use of special fan and damper arrangements, are mainly for smoke or early phase fire control when the fire

does not involve the air-handling equipment directly. For this reason,

the buildings’s air-handling system, adapted for smoke control, is

considered as an adjunct to, but not a replacement of a manual smoke and

fire venting system, as traditionally used by firefighters, to handle

high temperatures in the immediate fire area. These smoke control

systems are envisioned as operating best for the early phase of a fire

or in sprinklered buildings where the fire, if not extinguished, at

least is temperature controlled to the extent that a mechanical, airhandling system may be expected to sustain reliable operation.

The San Diego Veterans Administration (VA) Hospital is a modern,

sixstory structure with a 2.4-meter-high (8-foot) interstitial space

between each floor as shown in figure 1, the elevation sketch. Looking

at a typical floor, the building consists of four identical wings

connected to a central core in a symmetrical fashion as shown in figure

2. For a more complete description on the construction features of the

San Diego VA Hospital one may refer to reference [19] . A unique feature

of this building is that each floor of each wing has its own 100 percent

outside air system that can be controlled separately. A brief description of the air-handling system is contained in Appendix A of this

report. In view of this special capability, the National Bureau of

Standards (NBS) suggested that the airhandling units be programmed for

automatic horizontal and vertical smoke control.

A typical horizontal smoke control mode would have the fire wing

under 100% exhaust and the other three wings of the affected floor under

100% supply. As the smoke hazard becomes progressively worse additional

floors can be put into horizontal smoke control mode. This way smoke

may be prevented from leaving the affected wing.

In addition should smoke make its way into the central core an automatic vertical smoke control mode would go into operation such that

the affected floor will be under 100% exhaust and the floors immediately

above and below the affected floor will be under 100% supply. Should

the smoke hazard get progressively worse additional floors above and

below the affected floor can be put on 100% exhaust. Since it is far

more convenient to conduct horizontal evacuation in a hospital involving

invalid patients than vertical evacuation it is recommended that whenever applicable the horizontal smoke control mode should be initiated

first.

3
2. TEST METHODS

An extensive series of experiments designed to evaluate the above

smoke control concepts were performed by the NBS in cooperation with the

VA. Two types of experiments were performed with the building airhandling system operating in normal and various smoke control modes.

First, simulated smoke infiltration measurements were obtained by using

the sulfur-hexafluoride smoke simulation technique [6]. Second, pressure

measurements were obtained across elevator doors, and doors leading from

the building central core to each wing. Both SFg concentrations and

pressure measurements are key indicators of smoke movement in this evaluation.

2.1. Smoke Simulation Experiments

The smoke simulation experiments consist of the following salient

features. Smoke was simulated by a net airflow out of a designated

"burn-room" (locations of various burn-rooms used are indicated in fig- ures 3 to 5) . The air was mixed with a predetermined amount of sulfurhexafluoride tracer gas2 and heated to a temperature approximately 3

to 4 °C (4 to 6 °F) above the corridor temperature. The range of reference concentrations of the SFg tracer gas^ in the air from the burn-room

was of the order of 150 parts per billion (ppb), which was the maximum

reference concentration for each experiment. Six smoke movement simulations were conducted. Detailed conditions for each test are listed

along with measurements for that test in tables 2 to 7 and are explained

in section 3.

Prior to the beginning of each experiment the burn-room air was preheated to a temperature of approximately 27 °C (80 °F) by an electric

heater with a capacity of 1,650 watts. A window box-type fan at the

bottom of the doorway was used to draw the preheated air from the burnroom and blow it into the corridor. A cardboard mask was installed in

the hall doorway, in the same vertical plane as the fan, to allow air

from the burn-room only to be channeled through the fan. The measured

air-flow through the fan was approximately 15 cubic meters per minute

(500 cfm). This may typically represent a fire with a 2-pound per minute

burning rate. For a detailed comparison of the above simulation parameters in relation to the volume outflow, energy and burning rate in a real fire one may refer to the derivation and discussions in reference

[ 6 ].

SFg was chosen as a tracer gas because of its electron capture property

for detection, as well as being odorless, colorless, harmless and stable.

Occupational Safety and Hazard Administration (OSHA) concentration limits

of SFg is 1000 ppm as set forth in the Federal Register, Volume 36,

No. 157, August 13, 1971.

4
At the beginning of each test, a standard, lecture-size bottle of

SFg gas, located inside the burn-room behind the fan, was turned on to

continuously deliver a predetermined amount of SFg to the burn-room

air. The movement of the SFg throughout the building was then traced

by sampling at different building locations and the results are tabulated

in tables 2 to 7. The samples were collected by using individual 20

cubic centimeter syringes.

The air and SFg specimens taken at the several sampling locations,

were analyzed by use of a portable gas chromatograph having an electron

capture cell fitted with a 300 me of radiation source. The response of

the instrument to SFg is exponential and the usable range is between 1

and 1,000 ppb . If dilution of samples is necessary, syringes of various

sizes can be used.

Flow rates of the simulated smoke from the burn-room were determined

from velocity measurements made with a thermoanemometer having a low

range of 30 to 150 meters per minute (100-500 feet per minute (fpm)),

and a high range from 150 to 360 meters per minute (500 to 1,200 fpm).

Average velocities were obtained by making a traverse of nine points in

front of the fan or other openings.

2.2. Pressure Monitor Experiments

From the six basic air-handling tests described in table 1, pressure

difference data were collected at fifteen locations on each floor measured.

On at least two floors and more generally three floors, measurements were

taken for each test. The measured data are summarized in table 8.

The sampling locations are illustrated in figure 6. At every

location pressure differences were measured across a closed door with a magnehelic pressure gage of 2.5 to 125 Pascal (0.01 to 0 . 5-inch-H20)

pressure range. Sample locations 4, 7, 10 and 13 were taken across the

inner corridor doors which are normally open, providing one continuously

open and connected corridor throughout each floor. Sample locations 5,

8, and 14 were taken across external doors opening on to the outside

decks of the inner ring. Sample locations 6, 9, 12 and 15 were taken across external doors opening onto the outside decks at the outer perimeter of the building. Location 9 was directly exposed to the prevailing

west wind which was usually at a velocity of about 17.6 kilometers per

hour (11 mph)

.

3. RESULTS AND DISCUSSION

3.1. Smoke Simulation Experiments

A total of six smoke simulation experiments was conducted. The

results and test conditions for each test are tabulated in tables 2 to

7 inclusively. The highlights of the experiments are as follows:

4 Cylinder dimension: 5.08 cm x 38.10 cm. Contains: 1-1 kg of SFg in

liquid form under 22*06 x 10 Pascals pressure at 20 °C.

5
1. Smoke Simulation Test No. 1 (table 2, figure 3) — In this case the

HVAC system was in a normal mode. The simulated burn-room was on the

third floor. As shown by the graphs in figure 7 infiltration of SFg was extensive throughout the entire third floor. In 20 minutes the

SFg concentration at third floor central core (the elevator lobby) was as high as 18% of burn-room concentration. (In the following

all concentration measurements in parts per billion were normalized

by the burn-room concentration to yield percentage concentrations.)

The concentration at the central core measured to 34% at one hour.

Horizontal SFg infiltration of other wings on the third floor was

also extensive as shown by the concentration growth of the third floor

East and West wings in figure 7. Note that above the fire floor,

at the fourth floor, a gradual increase in SFg contamination was also

detected

2. Smoke Simulation Test No. 2 (figure 3) — In this case the HVAC system

was in a control mode, as follows:

(1) The south wing of the third floor was placed on exhaust

only and the burn-room was located in this wing.

(2) The East, West and North wings of the third floor were

placed on supply only.

(3) The third floor interstitial exhaust fans were turned

off except for the South wing.

(4) The balance of the building. operated in a normal mode.

Results in table 3 clearly showed the effectiveness of the horizontal

systematic pressurization smoke control concept. The only SFg measurements detected outside of the third floor South wing (the location of

the burn-room) were in the interstitial space immediately over the burnroom. No trace of SFg was detected in the other wings of the third

floor, nor was SFg detected on the fourth or sixth floors.

3. Smoke Simulation Test No. 3 — In this case the simulated burn-room

was located in the central core on the second floor (figure 4).

The second floor interstitial fans were off and the balance of the

building remained in a normal HVAC mode. The SFg concentration in

central core (see figure 8) rose rapidly to 56.3% in 20 minutes.

In both the West and North wing, the SFg concentrations, as shown in

figure 8, rose rapidly also (solid lines).

4. Smoke Simulation Test No. 4 — In this case the simulated burn-room

was located on the second floor in the central core as shown in figure

4 (same as test 3) . The second floor was placed on exhaust only,

the third floor was placed on supply only, the third floor interstitial fans were turned off, and the balance of the building remained

in a normal mode.

6
Results of this test are also plotted as dotted lines in figure 8

and are summarized in table 5. The difference between the smoke

control mode and normal mode is very pronounced. Not only was there

no SFg detectable away from the fire floor during smoke control mode

operation, but the total contamination on the fire floor was also

substantially reduced in all wings except the South wing during the

vertical smoke control mode. The higher concentration of SFg showing

up in the second floor South wing appears to be a result of airhandling system inbalance resulting in greater exhaust on the South

side.

5. Smoke Simulation Test No. 5 — This was a smoke decay study of the

third floor South wing interstitial space. The test conditions and

burn-room conditions for this test are listed in table 6. At time zero release of SFg was discontinued, after an initial concentration

level as tabulated in table 6 was reached. At that time the interstitial fan was turned on and the decay of the initial concentration

was monitored.

Results of this study are tabulated in table 6. The SFg concentration

decay in the South wing (where the burn-room is located) is plotted

in figure 9. Note in the plot, the data points after taking their

logarithm value follow a linear decrease. This indicates that the

decay behaved essentially exponentially as expected, and at half-anhour the concentration in the South wing has dropped at 1.3% of the

original concentration.

6. Smoke Simulation Test No. 6 — This case was a test to evaluate the

exhaust fan in the third floor interstitial space. The SFg was released directly in the interstitial space and the HVAC system was

in the normal mode. The interstitial exhaust fan was on.

Results of this test are tabulated in table 7. The SFg release and

sampling stations in relation to the exhaust duct location are shown

in figure 5. It appears from this test that the exhaust fan in the

interstitial space was able to channel the SFg gas straight through

without contaminating the interstitial space.

3.2. Pressure Monitor Experiments

The pressure tests were conducted under the temperature and wind

conditions listed in table 8. Since the indoor and outdoor temperature

differences were small we did not expect much pressure difference due to

the stack effect. Appendix B shows a derivation of the stack effect.

For reference, figure 10 presents the pressure difference due to stack

effect as a function of height and outdoor temperature. Note in figure

10 that the neutral plane is assumed to be at mid-height.

7
The pressure test configurations are summarized in table 1 and the

results in table 9. Since only a small stack effect was expected, as discussed before, it can be concluded that the typical measured pressure

difference in Test No. 1 of 2.5 Pascals (.01 inches H2 0) was probably

attributable to the air-handling system. Also, as there is no definite

recognizable pattern it can be conjectured that the measured pressure distribution was due to the balance of the air-handling units.

In the subsequent tests, when the air-handling units were put into

smoke control modes by unbalancing the system, definite pressure patterns

then emerged. These are illustrated by figures 11 and 12. In figure 11

data is taken from test 5, location 3, figure 6 which is the freight

elevator shaft. It can be seen that the directions of the measured

difference indicates that the flow was from the second and fourth floor

into the elevator shaft. On the third floor (fire floor), flow direction

was out of the shaft. This flow achieves the purpose of vertical systematic pressurization, which is to prevent flow of smoke from infiltrating

the second and fourth floor. For reference, the pressure difference due

to stack effect for a typical San Diego winter is plotted for comparison.

In figure 12, data are taken from test 2, second floor locations 4,

7, 10 and 13; figure 6. It can be seen that the measured pressure differences indicated that all flow was towards the South wing. This achieves

the purpose of horizontal systematic pressurization, which is to keep the

smoke from leaving the South wing through the core and thus infiltrating

the other wings or the other floors.

Pressure test numbers 3a through 3e were essentially a repeat of

test 2 except certain doors were opened to investigate the possibility

of defeating the preferred pressure pattern set up by the horizontal

systematic pressurization. The variations from the basic test 2 configuration (see fig. 6) are detailed as follows:

Case 3a

Case 3b

Case 3c

Case 3d

Case 3e

Inner corridor doors to the West wing closed and West wing

external door open (location 9) on the 3rd floor.

Same as 3a except East wing (location 15) instead of West wing.

Same as 3a except North wing (location 6) instead of West wing.

Same as 3a except South wing (location 12) instead of West wing.

All inner corridor doors and external doors closed. See note on figure 6.

Since there was a prevailing Westerly wind of approximately 18 kmph

(11 mph) , test 3 gave a good opportunity to see if significant wind

pressure can defeat the horizontal systematic pressurization concept.

In Appendix C a derivation was shown for the relationship of the maximum

pressure induced by wind. The relationships were then plotted in figure

13 on semi-log paper. From this plot we see that a wind of 18 kmph (11

mph) can induce a maximum pressure of approximately 17.5 Pascals (0.7

8
inches H2 O) , which is a significant pressure in relation to the measured

operating pressures of the horizontal smoke control mode in test 2. However, the results of test 3, as tabulated in table 9, clearly indicated

that the westerly wind did not affect the preferred smoke control pressure pattern as established by the air-handling system.

3.3. Computer Analysis of Smoke Movement

3.3.1. The Computer Program

The objective of a smoke control system is to provide dependable

smoke control to reduce the hazard to life from smoke movement at a minimum cost. In order to evaluate the effectiveness of any smoke control

system we need to know the reduction in smoke levels in the various

designated refugee areas and escape paths of a high-rise building, as a function of time during a fire. As a first step in obtaining this quantitative concentration information we have initiated this series of

smoke simulation experiments by using the SFg tracer gas technique. But

large-scale experiments like these are time consuming and expensive and

thus are necessarily limited in scope. Large-scale field experiments of

this type also are subject to the limitations of a given design, the prevalent weather conditions, and the exisiting building operations. Thus,

a more comprehensive study of smoke control design for a given building

can best be accomplished by computer modeling.

The task of creating a general computer smoke movement program valid

for today’s buildings is a difficult one. First, the known physical laws are complex; second, the buildings can be complicated, and the smoke paths can be numerous and hidden. The main motivation forces that cause smoke

movement in a high-rise building has been discussed in the Introduction

section of this report. These include, buoyancy and expansion forces

due to a fire, pressure forces due to wind, stack effect and the heatingventilating system. Based on the above smoke movement principles, a com- puter program can be written to simulate rooms and corridors connected by

leakage paths. A mass balance is then performed on this system with the

flow governed by a generalized orifice flow equation which is temperature

compensated. This system of simultaneous equations, characterizing the

building as a complex airflow network, is then solved by a nested iterative approach. Given the calculated rates and directions of airflow in

a building, it is then possible to determine the smoke concentration

distribution as a function of time and relative to the burn-room concentration.

3.3.2. The Assumptions

Because of the complexity of the problem, many simplifying assumptions were necessary to keep the calculation tractable. The principal

assumptions are as follows:

9
1. We are dealing with a small fire, so that the energy output by the HVAC system is large relative to fire size. A

consequence of this is that, except in the immediate neighborhood of the burn-room and its connecting corridor, the

smoke has essentially been cooled to the same temperature

as its surrounding air. Consequently, at distances from

the fire we can calculate smoke movement according to con- ditions of normal ventilation flows.

2. The flow calculations are based on a steady-state fire

condition.

3. Distribution is considered instantaneous within a given

compartment, such that the concentration at any given

time within that compartment is uniform.

Some of these assumptions can be relaxed and the calculations improved

as we gain more experience in applying the program. At the present

stage of development the program represents our present state of knowledge

about important contributing factors affecting the movement of smoke.

3.3.3. Building Configuration Properties

The primary problem identified with earlier published air movement

programs was the lack of a realistic modeling ability for the spatial

configurations of buildings and the components, and the arrangement of

the HVAC system. The current computer program design which was developed

and is now being utilized, has the capability of simulating:

1. Up to 100 floors;

2. A single corridor on each floor;

3. Up to 10 compartments which can be related to zones, suites, or specific spaces on each floor;

4. Up to 25 HVAC systems, each composed of:

a. An air-handling unit (AHU) (blower/fan) which delivers

air to the supply duct network,

b. A supply duct network,

c. A return air duct network or plenum,

d. An outside air supply shaft or duct to the AHU inlet,

e. A return air coupling to the AHU inlet to supply

recycled air,

10
f. A means to provide any mixture of outside air (OA) or return air (RA) , from 100% OA to 100% RA, to

the AHU,

g. A ventilation shaft or duct to exhaust return air

not recycled, and

h. An exhaust fan for the ventilation shafts.

5. Up to 20 different fans/blowers for use anywhere in the

building/HVAC system.

6. Up to 90 shafts or ducts made up of any combinations of

the following, except as indicated:

a. Elevator shafts to a maximum of 16,

b. Stairwells,

c. Air supply ducts/shafts,

d. Ventilation ducts/shafts,

e. Cable/pipe/duct shafts,

f. Window HVAC unit pipe shafts.

7. Up to 70 sets of non- fan /blower coupling parameters.

8. Up to 10 external wind functions which are linearly variable

as a function of height.

9. Up to 20 single temperature values for spatial temperature

specification and 20 temperature-height functions for shaft/

duct temperature specification.

Many other features are also included in the program design, such as

1. Inlet fans /blowers to pressurize shafts, such as stairwells;

2. HVAC air supply to stairwells;

3. External leakage to

a. Corridors,

b. Compartments,

c. Stairwells, to a maximum of 20,

d. HVAC window unit shafts.

11
4. Ventilation fans from corridors and compartments to

ventilation shafts and directly to the outside, and

5. Outlet fans from the various forms of shafts.

Although all characteristics of all building/HVAC systems cannot

be specifically represented by the capability of the computer program

developed, the functional representation of almost all characteristics

can be modeled by imaginative use of the available characteristics.

3.3.4. Field Trip Comparisons and Parametric Studies

In order for the computer program to be useful in evaluating the

smoke control system, and as a design tool, the following tasks need to

be performed:

1. In applying the program a complete specification must be

made from the architectural drawings of the layout of the

building of the spaces, the vertical and horizontal connecting paths, and the exact layout and specification of the

HVAC systems and smoke control flow input. Also, it is

necessary to establish the building leakage characteristics

through walls and floors; the size of cracks around doors

and windows, and which doors and windows are open. In

addition, the fire must be characterized in terms of its

temperature, pressure, volume outflow, and smoke concentrations. Finally, the environmental conditions prevailing

at the time of the fire must be determined.

2. Due to the complexity of the numerous inputs needed to

specify the basic model of a building it is almost imperative that the computer program be "calibrated" for each

building before any reliance on the application of the

computer program for smoke control studies, controlling

variable (parametric) and design studies. The "calibration"

approach adopted in the present study is first to obtain

a set of field pressure measurements from strategic locations throughout the building with the building HVAC

system in normal operation. This basic set of pressure

measurements then serves as an input for the specification of building leakage in the computer program. The

computer building leakage input is considered to be

"calibrated" for a given building when the computer output

simulating the building in normal HVAC operation matches

the basic pressure measurement.

3. A calibrated computer program can now be used to predict

smoke concentrations as a function of time with the

building HVAC system under various smoke control operations, and to verify experimental findings. In addition.

12
a calibrated computer program tailored to a given building can become a powerful tool in extending the validity

of any given smoke control concept under varying environmental conditions and internal building modifications, and

leakage parametric variations (door and window openings,

etc.)* A calibrated computer program is also the most

efficient tool for smoke control design optimization

studies by varying the needed airflow requirements.

3.3.5. Computer Simulation of the San Diego VA Hospital

A computer simulation, field test comparison and parametric analysis

for this hospital were performed to confirm and extend the results of our experiment findings. Details of the building characterization,

input description, model calibration, field test comparisons, and parametric studies for varying door openings and wind conditions are con- tained in Appendix D to this report [24].

The comparative results, in general, are in good agreement. This

implies that the computer simulation model utilized was reasonably representative of the building and the test conditions at the time of the

field pressure difference collection. The elevator pressure difference

comparisons appeared to be somewhat better than the outside wind function

and external door comparisons. Overall behavior appeared to be consistent

and representative of the actual building system. Occasional points

varied, but there was uncertainty about some of the measurements taken,

as well as the wind that fluctuated.

4. CONCLUSIONS

1. Based on the SFg concentrations and pressure difference measurements for the two simulated smoke control modes discussed in

sections 3.1 and 3.2 one can conclude that air-handling systems

in the San Diego VA Hospital can be effective in controlling

smoke movement in a typical San Diego climate if the proper

vertical and horizontal systematic pressurization concepts as described in this report are applied.

2. Results of the computer simulation of smoke movement in the VA

Hospital indicate the capabilities of the computer program to

confirm and extend the results of our experimental findings.

This signals the application of computer simulation for smoke

control design optimization and design guidelines by parametric

variations of building characteristics and environmental conditions .

13
5 . REFERENCES

[1] McGuire, J. H. , Control of Smoke in Building Fires, Fire Technology,

Vol. 3, No. 3 (Aug. 1967).

[2] McGuire, J. H. , Control of Smoke in Building Fires, Fire Technology,

Vol. 3, No. 4 (Nov. 1967).

[3] Tamura, G. T. and Wilson, A. G., Building Pressures Caused by

Chimney Action and Mechanical Ventilation, ASHRAE Transactions,

Vol. 73, Part II (1967).

[4] Tamura, G. T. and Wilson, A. G. , Pressure Differences Caused by

Chimney Effect in Three High Buildings, ASHRAE Transactions, Vol.

73, Part II (1967).

[5] Barrelt, R. E. and Locklin, D. W. , Computer Analysis of Stack

Effect in High-Rise Buildings, presented at ASHRAE 1968 Annual

Meeting at Lake Placid, New York (Aug. 1968).

[6] Fung, F. C. W. , Evaluation of a Pressurized Stairwell Smoke Control

System for a 12-story Apartment Building, National Bureau of

Standards (U.S.), NBSIR 73-277 (June 1973).

[7] Galbreath, M. , McGuire, J. H. and Tamura, G. T. , Exploratory

Paper on Control of Smoke Movement in High-Rise Buildings, NRC

No. 11413, National Research Council of Canada, Ottawa, Canada

(1970).

[8] Fung, F. C. W. and Ferguson, J. B. , Test and Evaluation of the

Smoke Control Features of the Seattle Federal Building, Proceedings

of the Public Buildings Service International Conference on Firesafety in High-Rise Buildings, held in Seattle, Washington (U.S.)

(Nov. 1974).

[9] Fung, F. C. W. , Smoke Control by Systematic Pressurization, Fire

Technology, Vol. 11, No. 4 (Nov. 1975).

[10] Fung, F. C. W. and Zile, R, H. , Evaluation of Smoke Proof Stair

Towers and Smoke Detector Performance, National Bureau of

Standards (U.S.), NBSIR 75-701 (Sept. 1975).

[11] Butcher, E. G. , Fardell, P. J. and Clarke, J. , Pressurization

as a Means of Controlling the Movement of Smoke and Toxic Gases on Escape Routes, Joint Fire Research Organization Symposium No. 4,

Movement of Smoke on Escape Route in Buildings, Paper 5, Watford,

England (1969).

[12] Butcher, E. G. and Hall, M. , Smoke Tests in New Law Courts Building,

Joint Fire Research Organization Research Note No. 889, Borehamwood,

England (1971).

[13] Mechanically-Ventilated Smoke Proof Enclosure, Los Angeles Fire

Department, City of Los Angeles BFP and PA Requirement No. 56 (1970).

14
[14] Butcher, E. G. , Cottle, T. H. and Bailey, T. A., Smoke Tests in

the Pressurized Stairs and Lobbies of a 26-Story Office Building,

CP 4/74, Building Research Establishment, Fire Research Station,

Borehamwood, England (Jan. 1974).

[15] Barrett, R. E. and Locklin, D. W. , Computer Analysis of Stack

Effect in High-Rise Buildings, presented at ASHRAE 1968 Annual

Meeting at Lake Placid, New York (Aug. 1968).

[16] Erdelyi, Bayliss J. , Test Results of a Ducted Stairwell Pressurization System in a High-Rise Building, Proceedings of a Symposium

entitled: Fire Technology Developments that Affect the ASHRAE

Engineer, ASHRAE Semi-annual Meeting held in Atlantic City, N.J. on Jan. 26, 1975. ASHRAE Journal (Feb. 1976).

[17] Taylor, Robert E. , The Carlyle Apartment Fire — A Study of a Pressurized Corridor, Proceedings of a Symposium entitled:

Fire Technology Developments that Affect the ASHRAE Engineer,

ASHRAE Semi-annual Meeting held in Atlantic City, N.J. on

Jan. 26, 1975. ASHRAE Journal (Feb. 1976).

[18] Tamura, G. T. , McGuire, J. H. and Wilson, A. G. , Air-handling

Systems for Control of Smoke Movement, ASHRAE Symposium Bulletin

Fire Hazards in Buildings (Jan. 1970).

[19] Schmidt, W. A. , Built for Tomorrow's Needs, Hospitals, Journal

of the American Hospital Association (Feb. 1970).

[20] Tamura, G. T. and McGuire, J. H. , The Pressurized Building Method

of Controlling Smoke in High-Rise Buildings, NRCC 13365, National

Research Council, Ottawa, Canada (Sept. 1973).

[21] Tamura, G. T. , Experimental Studies on Pressurized Escape Routes

ASHRAE Transactions, Vol. 80, Part 2 (1974).

[22] DeCicco, R. R. , Smoke and Fire Control in High-Rise Office

Buildings, Part I — Full Tests for Establishing Standards,

Presented at ASHRAE Symposium on Experience and Applications

on Smoke and Fire Control, Louisville, Kentucky (June 1973).

[23] Cresci, R. J. , Smoke and Fire Control in High-Rise Office

Buildings, Part II — Analysis of Stair Pressurization Systems,

presented at ASHRAE Symposium on Experience and Applications on Smoke and Fire Control, Louisville, Kentucky (June 1973).

[24] Fothergill, J. W. , Fothergill, P. A. and Johnson, M. A.,

Development of an Air Movement Simulation Program, Integrated

Systems, Inc., Md., U.S.A. (See Appendix A, and B of this report).

[25] Schmidt, W. A., HVAC Systems Can Save Lives, ASHRAE Journal

(Feb. 1976).

15
Table

1.

San

Diego

Pressure

Test

Configurations

16
Table 2. Third Floor Smoke Simulation with HVAC

in Normal Mode

Sample Normalized SF 6 Concentration** at;

Location*

5 min. 20 min. 35 min. 60 min.

3-1 14.6 19.8 25.6 34.5

3-2 6.1 22.2 32.1 34.5

3-3 6.1 18.0 27.0 34.0

3-4 6.8 6.8 9.8 13.0

3-5 1.3 — 2.6 3.3

31-1 1.3 — 3.3 4.0

31-2 0.6 0.6 1.3 1.0

4-1 0.0 1.3 1.6 2.6

4-2 0.0 1.6 2.6 2.6

4-3 0.0 — 2.6 2.6

4-4 0.0 1.3 2.6 1.6

4-5 0.0 1.3 2.6 1.6

First number indicates floor number, second number indicates

third floor sampling location as shown in figure 3. I denotes interstitial space.

* * Percentage SF 6 concentration normalized with respect to

burn-room concentration.

Test Conditions:

1. HVAC system in normal mode.

2. Third floor interstitial exhaust fans on.

3. Simulated burn-room: Room 3179.

Burn-Room Conditions:

1. Out flow from burn-room 13.42 cubic meters (474 cfm) per

minute

.

2. SF g concentration: 121.6 ppb.

3. Pressure differential across doorway: 45 Pascals (0.18

inch H 2 0)

Temperatures

Outdoor: 18.3 °C (65 °F)

Indoor: 23.9 °C (75 °F)

Burn-room: 26.7 °C (80 °F)

17
Table 3. Third Floor Smoke Simulation with HVAC

in Control Mode

Normalized SF c Concentration** at;

1 LUll

10 min 30 min 40 min

3-1 63.1 86.0 86.9

3-2 0.0 0.7 2.0

3-3 0.0 0.0 0.0

3-4 0.0 0.0 0.0

3-5 0.0 0.0 0.0

31-1 0.6 8.6 18.6

31-2 0.0 0.0 0.0

4 All samples on the fourthl and sixth

6 floors showed no traces of SF 6 contamination

.

First number indicates floor number, second number indicates

third floor location as shown in figure 3. I denotes interstitial space.

•k * Percentage SF 6 concentration normalized with respect to

burn-room concentration.

Test Conditions;

1. Third floor south wing exhaust.

2. Third floor north, east, west wings supply.

3. Third floor interstitial exhaust fans off except south

wing 31 exhaust which was on.

4. Rest of building HVAC normal.

5. Simulated burn-room: Room 3179.

Burn-room Conditions

:

1. Out flow from burn-room: 11.33 cubic meters (400 cfm)

per minute.

2. SF 6 concentration: 114.2 ppb.

3. Pressure differential across doorway: 45 Pascals (0.18

inch H 2 0)

.

Temperatures

:

Outdoor: 20.6 °C (69 °F)

Indoor: 23.9 °C (75 °F)

Burn-Room: 26.1 °C (79 °F)

18
Table

4.

Second

Floor

Smoke

Simulation

with

HVAC

in

Normal

Mode

a) • rH c a 0 g •H

fd -p

CO fdp p •P 0 c 0 CD rH O

MH

C0

T3

O

C0 g o 0

0) 0

cop

CO 0 c

(D 0 p

-p td 3

fd

a 12

O C0 •H 0

T3 -H -P c <d rH *rH -P P O P -h CD

<D P a

X) CO CO 6 P CD 3 CD P C -Pc JZ

T3 -H

p c •H 0 CO 3 O CD 0 -P

CO 0 CD c N • - CD •rH »p P T3 rH MH

<D fd 0 • 12 H g *3" g P CO rH d 0 d O c • c fd CN

»P

p c g o a) 0 rH 0 o p •H fd 0

r-l

a -p

H OS 4H CP fd -p

•rH

p •H

CO *4H -P . p .. CD e <D co e

-P

C CDd

p o

<d "H 0 0 CD 0 o C g p p H C 0 C 1 TS 3 o HH C C 0 fd p

•H jC M3 • • g

p 3

CO Cm CO P 0 XI P CO c 0 0

CD CO 0 CH-O

xi fd (D •H «P CD g CP •p C -P 3 c fd •rH •h t3 <d C 0 -P T3 C rH •H C C U 0 3 p -p CD 0 < O g

co fd

O

u > <D -H P 0 P 3C CO CO •H 0 CD •p

Cm rH a. CO

CD Eh p-I <n ro

<D P o 3 CM C CC •Hg x:o P c

CD •H a

VO

rH

g • 4H o o —

VO CO rH rH

CT fd —

u

CO

CO fd p 04

CD -p o

CDgu .. •H >i

12 (d 3 3 O P0

00 0

r~ • T3 • XI

r—1

CP CO rH a co0

rH P • • • O g ^ fd 0 cn 0 rH rH P fd 1 •H c .. 4J • • p C C

CO 3 0 CD c 12 •H P o -P CD •H g <d cp p 0 P P

•H P 4J -H

TD P C T3 C CD 0 3 O CD U 0 C P

rH 0 3 g HH O CO 0 CO 0 -P ^ CD OS 3 Cm P 1 O CO CP cp3 • . • CQ i—f

cm ro

Cmo

ooUo

CM

CO

CDp3p •• fd P p o

<d o a t3 go 3

&H o

19

20.6

°C

(69

°F)

Indoor

23.9

°C

(75

°F)

Burn-Room

27.
Table 5. Second Floor Smoke Simulation with

HVAC in Control Mode

Sample

Location

Normalized SFg Concentration at:

5 min 15 min 25 min 35 min

2-1 Center 0 .

0

1.2 1.2 3.8

2-2 East 0 .

0

0.0 0.0 0.0

2-3 North 0.0 0.0 0.0 0.0

2-4 West 6.9 12.4 8.6 14.0

2-5 South 17.3 30.1 33.2 33.2

21-1 0.6 1.2 0 .

6

0.6

3 All measurements from the third and sixth

6 floors showed no traces of SF 6 contaminat ion

First number indicates floor number, second number indicates

second floor location as shown in figure 4. I denotes

interstitial space.

k * Percentage SF 6 concentration normalized with respect to

burn-room concentration.

Test Conditions:

1. Second floor 100% exhaust, 5 Pascals (.02" H 2 0) Ap across

elevator doors, flow from elevator shaft to floor.

2. Third floor 100% supply 5 Pascals (.02" H 2 0) Ap across

elevator doors, flow from floor into elevator shaft.

3. Third floor interstitial fans off.

4. HVAC normal in the rest of the building.

5. Simulated burn-room: Room 2014.

Burn-Room Conditions:

1. Out flow from burn-room: 11.89 cubic meters (420 cfm)

per minute

2. SF 6 concentration: 130.4 ppb.

3. Pressure differential across doorway: 40 Pascals (0.16

inch H 2 0)

Temperatures

Outdoor: 21.2 °C (70 °F)

Indoor: 23.9 °C (75 °F)

Burn-Room: 27.2 °C (81 °F)

20
Table 6. Third Floor SF 6 Decay Study

Sample

Location*

Normalized SF 6 Concentration** at:

i 0 min 10 min 20 min 30 min

j 3-1 Center 53.5 17.1 3.4 1.3

3-2 East 0.8 0.0 — —

3-3 North 0.8 0.0 — —

3-4 West 1.7 0.0 — —

3-5 South 0.8 0.0 — —

31-1 9.0 8.0 3.9 3.0

31-2 0.9 0.0 0.0 0.0

* First number indicates floor number, second number indicates third floor location as shown in figure 3. I denotes

interstitial space.

"k k

Percentage SF

& concentration normalized with respect to

burn-room concentration.

Test Conditions:

1. 31 interstitial exhaust fan on.

2. HVAC system in normal mode.

3. Simulated burn-room before shut down: Room 3179.

Burn-Room Conditions:

1. SF 6 release turned off at time zero.

2. Burn-room fan shut down at time zero.

3. Initial burn-room concentration: 99.94 ppb.

Temperatures

Outdoor: 20.6 °C (69 °F)

Indoor: 25.0 °C (77 °F)

Burn-Room: 26.7 °C (80 °F)

21
Table

7.

Third

Floor

Interstitial

Space

SF6

Purging

Study

>1

g rH i Id •H p p o E o o o g o 0 • • • 1 0 0 p ID

in o o o 1 o o •H

p

g rp o o P -H •H 1—1 1—1 g Td o g u 0 0 •H O

rH

Ug

g N’

p o • g 0 P H

•H o g

p CN E o o o ' 1 rQ g • • • 1 P p

p o o o o o o in

p • • g o o r

cd

g rH

rH 1—1 p 0 0 g * •H &H o • •H * p: g g P g p tji 0 ro •rH 0 •H u P

•H

W P 0 0 p g 0 E P • P g •H p g g g P 0 p E o o o in ro g -h E Cn a P p • • • • • • 1 o •H •H CU g g in o o o o I—1

CN 1 •h

g

X

p

H 0 CN O'! Td £ g ID o g o E g • g •H X? •H ro o 0 0 ro u p P g rH pH 0 0 £ 0

<*D

p

g P o

id

g E o p • • in

CA "H

g 0 0 0 g r- E o o o in ID g p a 0

Td • • • • • 1 g 0 0 •H 0 in o o o o o O Td 0 g p

U

N i—1 O

g 0 P g

O •H 1 1 o g 0 p i—1 u 0 P o p CTi g (D -H P g g • g 0 p 0 ro p g 5 0 0 CN 0 - o g • :z g P 0 Td rH 0 g

•H o o o ID ID ID 0 rH 0 g

u 0 • • E • • • • • • p N •H P o o o O O r-~ E 0 •H p tD g 0

in

g

p i—1

•H Id

g 0 g a g p CA p Td E E 0 g p g • p p 0 p H 0 0 0 o 0 o 0 0 o g p g g P H g g a, g

g P ro

ag •H 0 p

•H o o o o o o 0 0 X E • • • • • • 1 0 •H g i—1 0 • !d o o o o o o 1 0 • r—i p 0 g 0 0 o P in g g a •H 0 Td g p o p o o o U 0 p p •H g E r-~ •H p •H g g P id —

Td

gp 0 •rH 0 0 rH

K

g Cn 0 a P g

O

g •H *rH

p

g • •• Td 0 i—1 E O 0 p 0 0 0 0 0 P g p

•Hpgoop0

I—I ae

fd CA i—i cn ro l l l ro ro ro HNn l l l H M H

rom ro

4-) OgQP0g

fd pxw

go

-P P

-PC

•Hg

•H

a)>o 0 P g g o o

fd <d d

Cn 0 g —i

td 0 0 p

•H

-p •H 0 -P d 0 Co

•HP

•H

Tdgou

-p0

ai EH 0

fd0I—I 0p

IX> IdCA

g

•HEgE

•HxgS

•H

-p •Hp0p0pg ogg

•Hu<

cn ro 0 P 0 CN Pgp .. g p p o 0 o a tj E 4-> 0 g

Eh o

22
Table

8.

Temperature

and

Wind

Conditions

Direction Westerly Westerly Westerly Westerly Westerly Westerly

73 p: <D 00 00 CN CN CN CN CN 0 a • • CD g oo on cn oo oo i—i r"- t d, i—1 rH i—1 rH i—1 pH i

1 rH

03 '—

T3C p: o h in oo oo ^ *3* r~- oo oo •H a rH • • • • s g rH i—1 O O

i—1 rH rH H

• 0

H cn m ^

c

cd Cm

a 00 r" cj\ i-h r-i r- g u •

<1) 0 CN l—1 ^ n rl rl i—

1

Eh CM CN CN CN CN CN CN u

0

0

^3 Cm CO HlDinOON

P o r*- r— r" P —

O

a CO <Ti ^ CO CO CO CO g U • a) o m CO ^ CO CO CO CO

' ’ CN CN CN CN CN CN CN

sh0

0 Cm in co ^ ^ tj1 T3 o r-~ r- r" t"- f" r* C

’—

H

a) rH

cn rH rHcNn^mco

fd C

u

cn cn T3 C C

d) 0 iH 0 P -H cd *h

<d P p p

rH *H P -H P T3 O T3 g e < c H 0 0

03 (J y
Table

9.

Pressure

Difference

Across

Doors

CO CM CN

ro cm o o

+ I

CM CM CM CM CM CM

co co co

CM CM (M

cm vo co

co cm co in cm

CM CM in

u

<U 0 in co o CO T O

o o o o

4-> tn

in 1 1 + +

0) 'V

Eh p

co

p

TJ 0 in in

co o cm co m o

rH o o o o

-P

in l i + +

(U TJ

Eh P

co

P

U 0

1 o eg ^ rr rH

| iH o o o o

P t,

in 1 1 + +

0) T)

Eh P

CO

p

XI 0

co 0 co *3" vo i—

o o o o

-P u,

in 1 1 + +

(U TJ

Eh P

CO

P «—

03 0 o

co o

i—

(

P lu co H- VO CM

in O O O O

<D TD

Eh p 1 + + -1- CO

ItC0

•H

-P

03 1 O CO U rH rH 0

PJ

+ 1 +1

CM CN CM

C

•H

-Co

05

0)

d)U

o

in

in

(Up

vu

<D>

•HP

•H

ino

cu

24
a: o

crn

cro

0£o

cro cr z O

_i 3

5

_j

o_J o_J O

o

LU

2j

u. Lu Li_ Ll_ u. —i LU

-C .C JC T3 T

3

u_ tn

•4— w c <

10 in ro CVJ

</> on

fO

25

Figure

1.

Elevation

of

San

Diego

VA

Hospital
OUTSIDE

STAIRWELLS

bo £BM

Q»

26

Figure

2.

San

Diego

VA

Hospital

Typical

Floor

Plan
Figure 3. Third Floor, Floor Plan

27
Figure 4. Second Floor, Floor Plan

28
North

Wing H

11

29

Figure

5.

Sampling

Locations

for

Smoke

Test

(Samples

Collected

from

Third

Floor

and

also

Interstitial

Space)
West Wing

North Wing

7%

FI

rur.__

7 , /1

3

LL_L

10

14

<

South Wing

East Wing

Figure 6. Sampling Locations for Pressure Monitor Experiments

(Interior Corridor Doors 4, 7, 10, 13 were Open Unless Otherwise

Noted. All Other Exterior Doors were Closed Unless Otherwise

Noted .

)

30
CO

a>

i©

£

uiooy-ujng jo 4U90J9d ( uoi4dj4U90uoo 9js

31

Figure

7.

San

Diego

VAH,

Horizontal

Smoke

Movement

Experiment

[Test

1]
0) co

CO4> 4—3

C

i O)E

ujooy-iung jo *u9Djad ‘uojiDJiuaouoo 9jg

32

Figure

8.

San

Diego

VAH,

Vertical

Smoke

Movement

Experiment

[Tests

3

and

4].
TIMEMinutes

O

Natural log of percentage SF

6

Concentration (Table 6)

Figure 9. Third Floor SF6 Decay Study, Location 3-1 [Test 5].

33
.C o Q.OW

< .E CL lO in

34

Figure

10.

Stack

Effect

versus

Building

Height

for

Different

Outside

Temperatures
SMOKE

CONTROL

MODE,

FIRE

ZONE

3rd

FLOOR

35

Figure

11.

San

Diego

VAH

Elevator

Shaft

Pressure

Profile,

Smoke

Control

Mode

[Test

4].
SMOKE

CONTROL

MODE,

FIRE

ZONE

2nd

FLOOR

SOUTH

WING i

CL

Q.3

CO©fc= oo

O'cEo*o m

(A3O

.CX

LlI o»E?o

k.ooEo5o 2 T> - g

(O a> 2 o o <-> o —o

T3 >-° O'c 3

(AS £ E

o> ZS-o

w. a> o 3 £ T3

co

—

to t >

Q.2x»§ fE o° oo

CM M- - 1^- .c ° U- \ ° c

CD £ ^ - 1 ° - S O3C

O

0J X «oo

COo

CLO6 ° < .E

rO

m

O

n

CVJ o O in — m O CM

co o

Q)

O

.c

Q.E

T>C$ h-

— in O CM

OJ o O in

to

m

O P O —

36

Figure

12.

San

Diego

VAH

Center

Core

Pressure

Profile,

Smoke

Control

Mode

[Test

2].
Figure 13. Pressure versus Velocity Head

37
APPENDIX A. DESCRIPTION OF AIR-HANDLING SYSTEM

The air-handling systems for the San Diego VA Hospital are all

housed in the "interstitial space" between each floor. Each wing on each floor gets its own air supply unit and several exhaust fans. For a brief description of the construction features of the San Diego Hospital

and the interstitial space, one is referred to references [19] and [25].

Each air-handling system contains one supply unit (600 cubic meters or 20,000 cubic feet per minute) and several exhaust fans (total 480 cubic

meters or 16,000 cubic feet per minute) that are located in separate

mechanical rooms within the interstitial space. The rooms containing

the supply units are located close to the center core of the building and

the supply units draw 100 percent outside air through grills mounted in

the interstitial overhang. The exhaust equipment rooms are located in

the opposite end of each quadrant from the supply equipment rooms and are close to the end of each wing, permitting the wind to sweep the

exhaust away from the building and thus lessening the chance of cross contamination from the exhaust to the outside air intake. The air supply

systems are of the single duct, variable-volume- type with reheat coils

mounted in the volume control terminals. The moderate size of the airhandling units permits the units to be located in the interstitial spaces.

Moreover, these systems are capable not only of handling the initial

loads but, also, of handling increased loads, when they need to. Thus

the systems themselves can be modified without disruption of the entire

hospital or the entire floor. With ductwork, piping, and equipment mounted

within the interstitial space, servicing of the equipment as well as future modifications may be accomplished without disruption of patient

treatment

38
APPENDIX B. PRESSURE FORCE DUE TO STACK EFFECT

The well known stack effect in a high-rise building is caused by the

difference in hydrostatic pressure due to two air columns at different

temperatures. Thus the pressure difference is given by:

Ap = (p Q

- p) gh. (Bl)

where

p Q

= the outside air density

p = the inside air density

g = the gravity constant

h = distance from the neutral plane.

Assuming the ideal gas law

Ap = r^ " t

} h - (B2)

o

Considering standard atmospheric condition, we can express the above

as

Ap = 7.7 (j- - i) h.

o

where

h = is in feet

T = in degrees Rankine

Ap = in inches of water

or

where

Ap = 3600 h * o

h = height in meters

T = temperature in degrees Kelvin

Ap = pressure difference in Pascals

(B3)

(B4)

39
The above formula indicates that for a 100-ft tall building with

neutral plane at mid-height and a 70 °F temperature differential, a maximum of 0.1 inch H 2 O pressure difference can be induced by stack

effect

40
APPENDIX C. PRESSURE FORCE DUE TO WIND EFFECT

Consider air motion caused by a generalized pressure force, p. The

momentum equation for the flow field in this case can be simply written

as

,

pV • VV = - Ap

where

(Cl)

p = the gas density,

V = the gas velocity vector,

p = the pressure distribution of the flow field, and

V = the gradient operator.

Integrating (Cl) along the direction of smoke motion one obtains

1/ 2pV 2 = | Ap | (C2)

where

Ap = the pressure difference

Assume that gas density change is governed by the ideal gas law,

P

PRT (C3)

where

T = the absolute temperature, and

R = the gas constant.

Combining (C2) and (C3) and evaluating for air under standard atmospheric condition, with R equaling 53.3 ft lbf/lbra °R one obtains

V = 174 VApT

_

(C4)

where

V = velocity in feet per minute,

T = temperature in degrees Rankine, and

Ap = pressure difference in inches of H2 O.

41
or

V = 4.49VApT (C5)

where

V = velocity in meters per minute,

T = temperature in degrees Kelvin, and

Ap = pressure difference in Pascals.

42
APPENDIX D. FIELD TEST COMPARISON AND PARAMETRIC ANALYSIS

SAN DIEGO VETERANS ADMINISTRATION HOSPITAL

Development of an Air Movement Simulation Program

43
APPENDIX D. FIELD TEST COMPARISON AND PARAMETRIC ANALYSIS

SAN DIEGO VETERANS ADMINISTRATION HOSPITAL

DEVELOPMENT OF AN AIR MOVEMENT SIMULATION PROGRAM

J.W. Fothergill, P.A. Fothergill, M.A. Johnson

Prepared for:

Center for Fire Research

Fire Safety Engineering Division

National Bureau of Standards

Under Contract No. 5-35727

Integrated Systems, Inc.

(A Maryland Corporation)

11880 Coakley Circle

Rockville, Maryland 20852

44
TABLE OF CONTENTS

Section Page

INTRODUCTION 1

SIMULATION MODEL CONFIGURATION 3

CALIBRATION OF THE MODEL 6

Field-Collected Data 6

Wind and Temperature Parameters 16

Results of Computer Simulations for Calibration 19

SMOKE CONCENTRATION SIMULATIONS 50

Trace Gas Simulations 50

Computer Simulation of Trace Gas Tests 51

Smoke Test No. X 52

Smoke Test No. 2 68

Smoke Test No. 3 68

Smoke Test No. 4 69

Computer Simulation of Smoke Movement

on Pressure Tests 72

PARAMETRIC ANALYSIS 76

Scenario I 77

Case 1A - Failure State of Third Floor

HVAC Equipment 78

Case IB - Control Mode 84

Case 1C - No HVAC Failure 87

Scenario II 88

Case 2A - Failure State of the West Wing

HVAC Equipment 89

ii

45
TABLE OF CONTENTS (Cont.

)

Section Page

Case 2B - Control Mode at Nominal Wind Speed 89

Case 2C - Control Mode with a 25-mph West Wind 89

Case 2D - Normal HVAC State 103

CONCLUSIONS 104

REFERENCES 106

iii

46
LIST OF FIGURES

Figure No. Page

1. Sample Point Locations 13

2. Wind Effects 18

3. Simulated Elevator Shaft No. 1 vs Sample Point

No. 1 (Pressure Test Case No. 1) 20

4. Simulated Elevator Shaft No. 2 and 3 vs Sample

Point No. 2 (Pressure Test Case No. 1) 21

5. Simulated Elevator Shaft No. 4 and 5 vs Sample

Point No. 3 (Pressure Test Case No. 1) 22

6. Simulated Outside Wind Function No. 4 vs Sample

Points No. 6 and 15 (Pressure Test Case No. 1) 23

7. Simulated Outside Wind Function No. 3 vs Sample

Points No. 5, 8, 11, 12, and 14 (Pressure Test

Case No. 1) 24

8. Simulated Outside Wind Function No. 2 vs Sample

Point No. 9 (Pressure Test Case No. 1) 25

9. Simulated Elevator Shafts No. 2 and 3 vs Sample

Point No. 2 (Pressure Test Case No. 2) 26

10.

Simulated Elevator Shaft No. 1 vs Sample Point

No. 1 (Pressure Test Case No. 2) 27

iv

47
LIST OF FIGURES (Cont.)

Figure No. Page

11. Simulated Elevator Shafts No. 4 and 5 vs Sample

Point No. 3 (Pressure Test Case No. 2) 28

12. Simulated Outside Wind Function No. 4 vs Sample

Point No. 9 (Pressure Test Case No. 2) 29

13. Simulated Outside Wind Function No. 4 vs Sample

Points No. 6 and 15 (Pressure Test Case No. 2) 30

14. Simulated Outside Wind Function No. 3 vs Sample

Points No. 5, 8, 11, 12, and 14 (Pressure Test

Case No. 2) 31

15. Simulated Elevator Shafts No. 2 and 3 vs Sample

Point No. 1 (Pressure Test Case No. 4) 32

16. Simulated Elevator Shafts No. 2 and 3 vs Sample

Point No. 2 (Pressure Test Case No. 4) 33

17. Simulated Elevator Shafts No. 4 and 5 vs Sample

Point No. 3 (Pressure Test Case No. 4) 34

18. Simulated Outside Wind Function No. 4 vs Sample

Points No. 6 and 15 (Pressure Test Case No. 4) 35

19. Simulated Outside Wind Function No. 2 vs Sample

Point No. 9 (Pressure Test Case No. 4) 36

v

48
LIST OF FIGURES (Cont.)

Figure No. Page

20. Simulated Outside Wind Function No. 3 vs Sample

Points No. 5, 8 , 11, 12, and 14 (Pressure Test

Case No. 4) 37

21. Simulated Elevator Shafts No. 2 and 3 vs Sample

Point No. 2 (Pressure Test Case No. 5) 38

22. Simulated Elevator Shaft No. 1 vs Sample Point

No. 1 (Pressure Test Case No. 5) 39

23. Simulated Elevator Shafts No. 4 and 5 vs Sample

Point No. 3 (Pressure Test Case No. 5) 40

24. Simulated Outside Wind Function No. 4 vs Sample

Points No. 6 and 15 (Pressure Test Case No. 5) 41

25. Simulated Outside Wind Function No. 2 vs Sample

Point No. 9 (Pressure Test Case No. 5) 42

26. Simulated Outside Wind Function No. 3 vs Sample

Points No. 5, 8 , 11, 12, and 14 (Pressure Test

Case No. 5) 43

27. Simulated Elevator Shaft No. 1 vs Sample Point

No. 1 (Pressure Test Case No. 6 ) 44

28. Simulated Elevator Shafts No. 2 and 3 vs Sample

Point No. 2 (Pressure Test Case No. 6 ) 45

yi

49
LIST OF FIGURES (Cont.)

Figure No. Page

29. Simulated Elevator Shafts No. 4 and 5 vs Sample

Point No. 3 (Pressure Test Case No. 6) 46

30. Simulated Outside Wind Function ti>. 2 vs Sample

Point No. 9 (Pressure Test Case No. 6) 47

31. Simulated Outs de Wind Function No. 4 vs Sample

Points No. 6 and 15 (Pressure Test Case No. 6) 48

32. Simulated Outside Wind Function No. 3 vs Sample

Points No. 5, 8, 11, 12, and 14 (Pressure Test

Case No. 6) 49

33. Primary Smoke Routes at the 31 Level (Case 1A) 81

34. Primary Smoke Routes on the Third Floor (Case 1A) 82

35. Primary Vertical Smoke Routes (Case 17\) 83

36. Smoke Flow in Control Mode (Case IB) 86

37. Primary Smoke Routes on Third Floor Interstitial

Level 90

38. Primary Smoke Routes on Third Floor 91

39. Smoke Flow Paths from West Wing 31 92

vii

50
LIST OF FIGURES (Cont.)

Figure No. Page

40. Infiltration Routes Under Control Mode

(Case 2B) 95

41. Third Floor Smoke Routes (Case 2C) 90

42. Infiltration Routes Under Control Mode

(Case 2C) 99

viii

51
LIST OF TABLES

Table No. Page

1. Test Pressure No. 1 7

2. Test Pressure No. 2 8

3. Test Pressure No. 3 9

4. Test Pressure No. 4 10

5. Test Pressure No. 5 11

6. Test Pressure No. 6 12

7. Temperature and Wind Conditions 17

8. Smoke Simulation Comparisons - Smoke Test No. 1 at 5 min. 53

9. Smoke Simulation Comparisons - Smoke Test No. 1 at 20 min. 54

10. Smoke Simulation Comparisons - Smoke Test No. 1 at 35 min. 55

11. Smoke Simulation Comparisons - Smoke Test No. 1 at 60 min. 56

12. Smoke Simulation Comparisons - Smoke Test No, 1 at 10 min. 57

ix

52
LIST OF TABLES (Cont.)

Table No. Page

13.. Smoke Simulation Comparisons - Smoke Test No. 2 at 30 min. 58

14. Smoke Simulation Comparisons - Smoke Test No. 2 at 40 min. 59

15. Smoke Simulation Comparisons - Smoke Test No. 3 at 5 min. 60

16. Smoke Simulation Comparisons - Smoke Test No. 3

at 15 min. 61

17. Smoke Simulation Comparisons - Smoke Test No. 3

at 20 min. 62

18. Smoke Simulation Comparisons - Smoke Test No. 3

at 30 min. 63

19. Smoke Simulation Comparisons - Smoke Test No. 4 at 5 min. 64

20. Smoke Simulation Comparisons - Smoke Test No. 4 at 15 min. 65

21. Smoke Simulation Comparisons - Smoke Test No. 4 at 25 min. 66

22. Smoke Simulation Comparisons - Smoke Test No. 4 at 35 min. 67

x

53
LIST OF TABLES (Cont.)

Table No. Page

23. Smoke Test No. 4 - Pressure Comparisons 70

24. Smoke Simulation Comparisons - Smoke Test No. 2 at 60 min. 73

25. Smoke Simulation Comparisons - Smoke Test No. 6A

at 60 min. 75

xi

54
INTRODUCTION

Under the sponsorship of the Fire Research Center of the National

Bureau of Standards, a realistic computer simulation program was developed for predicting the steady state movement of air through

high-rise building complexes. The objective of this work was to

provide a more representative building/HVAC system modeling capability than was currently available (1) , (2) at the Fire Research

Center. The available air movement simulation capability (1) was based upon an extremely simplistic representation of a building/

HVAC system. Since the Fire Research Center had been and was con- ducting trace gas field tests of various Federally owned or con- trolled buildings to test, evaluate, and make recommendations for

smoke control features in these buildings, it was also necessary

to provide a means to simulate smoke concentrations within a building from a simulated source in the computer simulation capability.

However, this effort did not include the development of a "second

generation" smoke concentration computer simulation program which

matched the newly developed air movement simulation program. Rather,

it v/ as decided to achieve a meaningful air movement simulator in

this effort and attack the smoke concentration simulator at a later

time.

In order to provide a minimal smoke concentration prediction capability, an output data interface was developed in the new air move- ment simulator which was compatible to the smoke concentration simulation program currently available (1) at the Fire Research Center.

This allowed the use of a very limited portion of the simulated air

movement data to be input to a smoke concentration predictor. The

use of this smoke concentration predictor must be made with extreme

care, since its representation of a building/HVAC system is limited

to corridors coupled to a maximum of 10 vertical shafts and two ex- ternal walls. Results from the use of this smoke concentration

predictor can be completely misleading when it is coupled to the

newly developed air movement program.

1

55
In order to verify the newly developed air movement computer simulation and to demonstrate its capability, several buildings which

had undergone trace gas tests and pressure data measurement by personnel of the Fire Research Center were simulated to some degree

during this project. The most extensive computer simulation effort

was accomplished in the San Diego Veterans' Hospital. Three levels

of simulation were performed, i.e.:

1. Calibration of the parametric model of the

San Diego VA Hospital building/HVAC system

against pressure data collected on site

under various states of the building/HVAC

system

2. Simulation of the field-conducted trace gas

tests

3. Simulation of hypothetical conditions of

the hospital by varying different parameters

to gain insight into the level of effectiveness of the smoke control techniques available.

This appendix presents a description of the model of the hospital

used in the newly developed air movement program, the manner in

which the simulated model was calibrated, and the results of the

calibration, the trace gas tests simulated and the results of the

simulation, the parametric variations of the hospital's states

simulated and the results of these simulations, and some of the

conclusions reached regarding the use of the computer simulation

programs on this building.

2

56
SIMULATION MODEL CONFIGURATION

Many variations are available in the newly developed air movement

computer simulation program to represent a building such as the

San Diego VA Hospital. Three basic configurations were immediately

obvious, i.e.:

1. As one integral building with the interstitial

spaces represented as floors between the occupancy floors, one main corridor open and con- necting the core and all wings on each occupancy

floor, office spaces on occupancy floors represented as compartments connecting to the main

corridor, and the center core areas of the interstitial spaces as a pseudo-corridor with only

leakage penetrations connecting to the wing interstitial spaces represented as compartments.

2. As one integral building, defined as above, except

that the wing corridors would be separated from

the core corridor as another compartment which was

coupled to the wing compartments representing the

office spaces in the wings on the occupancy floors.

3. As five separate buildings composed of the central

core and wings connected by passageways between the core and the wings at each occupancy floor and each

interstitial level.

3

57
The first model defined above was selected because it most closely

represented the hospital in its normal mode. Separating the wing

corridors into separate compartment spaces would have allowed a means to evaluate lateral smoke movement. However, the currently

available smoke concentration simulator is not capable of simulating

lateral smoke movement and the results from the air movement program

could not have been utilized effectively. Use of the third model

suggested above would have presented modeling of the couplings of

the interstitial spaces with each other, and with common electrical

equipment shafts, plumbing shafts, and stairwells.

The office spaces from the second floor upward were lumped into a single compartment for the core and a single compartment for each

wing. This allowed a five-compartment representation on each

occupancy floor. Segregation could have been made to a maximum

of 10 compartments on each floor. However, it would not have provided any additional benefits to the simulation. The basement

and the first floor were each reduced to a corridor and one com- partment representation for all non-corridor space.

All of the inner stairwells and adjacent shafts were represented

and coupled as they actually occurred. The shafts adjacent to

stairwells 9 and 11 were also represented with their own air

supply, as actually occurs. The outer stairwells were reduced

to one on each wing rather than two because of the number and the

fact that the effect of two could be represented by one simulated

stairwell. The short stairwell connecting the basement and the

first floor was also represented, as were the plumbing risers.

All of the elevator shafts were represented as constructed,

including the animal elevator. The pneumatic trash and laundry

tube coupling was also represented as shown on the mechanical

drawings. Leakage between each corridor and the interstitial

4

58
space directly above was represented by the floor-to -floor leakage

term. However, the office space areas were coupled to their

interstitial spaces directly above by the use of pseudo shafts.

The availability of 90 simulated shafts and their versatility

allows them to be used to couple any building spaces and external

space as desired. Couplings between the wing interstitial spaces

representing plumbing and conduit penetrations were accomplished

in the same way.

Because of the limitations on the number of IIVAC systems allowed

by the program (25) , it was not possible to represent each individual A/C unit. Each occupancy floor was lumped for air supply

and air exhaust. However, each wing was represented correctly

in the amount of supply and exhaust as reflected in the mechanical

drawings. The core was exhausted by an independent exhaust fan

representing TF-8. However, the penthouse was not modeled and the

simulated TF-8 exhausted directly to the external space from the

simulated sixth floor interstitial space.

One limitation was encountered in the program that hampered correct

representation. This was the limitation on blower or fan parametric representations. The program only allows the use of 20

fans. This creates the need to compromise on the specifications

of output capacities and static pressures so that each entry can

be utilized to represent more than one actual fan or blower. This,

in turn, creates difficulties in manipulation of the input data

to represent non-normal operating states, such as smoke control

modes of failure modes. The number of allowable blowers or fans

should be increased to approximately 50 at some time in the future.

5

59
CALIBRATION OF THE MODEL

Comparison of simulated smoke tests in a building, using a tracer

gas, with simulated computer smoke concentrations from the simulated model of the building does not provide an exact basis to

determine how well the computer model represents a building's

spatial configuration, air couplings and leaks, HVAC system, and

air flow. It is only of an indicative nature. However, fitting

the computer model to field-collected pressure difference data

taken at all major airflow couplings, e.g., elevator doors,

stairwell doors, etc., provides a very precise basis for adjusting the model to fit the air movement characteristics of a building. Consequently, pressure difference data was collected

in the San Diego building with the HVAC system in various modes.

This section presents the results of fitting or calibrating the

computer model of the San Diego VA Hospital to the fieldcollected pressure difference data.

Field-Collected Data

Six basic modes or conditions were established and pressure difference data was collected at 15 locations on each floor measured.

At least two floors and, more generally, three floors were measured for each mode. Each of the six modes are described in this

section and the measured data is presented in Tables 1, 2, 3, 4,

5, and 6. The sample points are illustrated in Figure 1.

The bank of elevators at sample location 1 are represented in a single sample. However, the banks located at sample location 3

is composed of two separate shafts and was simulated in that

manner

6

60
TABLE 1 TEST PRESSURE NO . 1

Floor 2 3 6 Sample

Point

1 + .01 + .00 -.01 !

2 + .00 + .00 -.01

3 +.01 +.01 + .01 -.01

4 + .00 + .00 + .01

5 -.02 + .00 + .02

6 -.01 +.01 + .01 + . 01 .

7 -.01 +.01 -.01 -.01

8 -.02 + .00 -.02 i

9 -.02 -.025 + .01

10 -.02 + .00 -.00

11 + .01 + .01 + .02

12 + .015 + .01 + .00

13 + .00 -.01 + .00

14 + .03 + .01 + .015

15 + .01 + .00 + .01 i

7

61
TABLE 2 TEST PRESSURE NO. 2

Floor 2 3 4 Sample

Point

1 .00 .01 .00

2 .00 .01 .00

3 .00 .01 .005

4 .00 -.03 .00

5 .00 + .00 -.015

6 .00 .015 .02

7 -.02 -.03 -.01

8 -.02 + .00 -.02

9 -.05 -.04 -.08

10 .00 .02 .00

11 + .01 .025 .03

12 -.02 .01 .02

13 .00 -.02 .01

14 .02 .02 .025

15 .00 .01

l

-.01

8

62
TABLE 3. TEST PRESSURE NO. 3

Floor 3a 3b 3c 3d

Sample

West Wing

Door Open

North Door -.03 -• u 3 -.02 -.02

South Door .06 .06 .04 .05

East Door .02 .01 .01 .005

West Door i • 0 1+ O -.04 -.04 -.035

Samples taken with center core corridors

closed at the center core corridor doors.

9

63
TABLE 4 'EST PRESSURE NO. 4

10
TABLE 5 TEST PRESSURE NO. 5

Floor

2 3 4

. Sample n.

Point

1 .035 -.02 .03

2 .03 -.02 .02

3 .035 -.02 .02

4 .00 -.025 .01

5 .03 -.02 . 025+. 005

6 .015 -.02 + .015

7 -.03 -.01 -.Oi

8 .015 -.02 + .04

9 -.015 -.06 -.04

10 -.01 .035 .00

11 .05 .01 .05+. 01

12 .07 -.01 + .02

13 .00 .025 .00

14 .035 .01 .045

15 .02 -.01 .01

11

65
TABLE 6 TEST PRESSURE MO. 6

Floor

4 5 6 Sample

Point

1 .04 -.03 .01

2 .03 -.03 .01

3 .03 -.03 .01

4 -.015 .015 -.02

5 .02 -.03 .01

6 .02 -.01

7 -.015 -.01 .01

8 • 035 -.015 .025

9 -.02 — -.04

10 -.01 O H 1 .01

11 .07 -.00 .04

12 .005 -.01 .01

13 .00 .02 - .01

14 .05 .00 . 045

15 .01 -.01 .00

12

66
67
The samples taken at location 3 were from both shafts. Consequently,

the sampled data from these locations must be compared with the

computer simulation results from the two shafts in each respective

bank of elevators.

Sample locations 4, 7, 10, and 13 v/ere taken at the inner corridor

doors, which are normally open, providing one continuously open and

connected corridor throughout each floor.

Sample locations 5 , 8 , 11 , and 14 were taken at external doors opening onto the outside decks of the inner ring.

Sample locations 6, 9, 12, and 15 were taken at external doors opening onto the outside decks at the outer perimeter of the building.

Location 9 was directly exposed to the prevailing west wind, which

was usually at a velocity of 11 mph.

The modes imposed during the field collection of pressure difference

data were as follows:

1. Pressure Test Case No. 1 - HVAC in normal mode.

2. Pressure Test Case No. 2 - South wing of third floor

on exhaust only, balance

of third floor on supply

only, balance of building

in normal mode.

3. Pressure Test Case No. 3 - Same mode as Test Case 2,

except as follows:

14

68
Case 3A

Case 3B

Case 3C

Case 3D

Case 3E

4. Pressure Test Case No. 4

5. Pressure Test Case No. 5. -

Inner corridor doors to the

west wing closed and west

wing external door open

(location 9) on the third

floor

Same as 3A, except east wing

(location 15) instead of

west wing.

Same as 3A, except north

wing (location 6) instead

of west wing.

Same as 3A, except south

wing (location 12) instead

of west wing.

All inner corridor doors

and external doors closed.

Entire third floor on exhaust only, entire fourth

floor on supply only, and

balance of building in normal mode.

Entire second and fourth

floors on supply only and

entire third floor on exhaust only.

15

69
6. Pressure Test Case No. 6 - Entire fourth floor on

supply only, entire fifth

floor on exhaust only,

except the west wing on

supply and exhaust, and

entire sixth floor on supply only, except the

south wing on supply and

exhaust.

Wind and Temperature Parameters

The indoor and outdoor temperatures, the wind yelocity existing

at the time each test was made, and the parametric values used

in the computer simulation are shown in Table 7 . The small variation in indoor and outdoor temperatures justified the use of

average values in the computer simulation.

The rationale used to represent the wind acting on the external

doors is illustrated in Figure 2. The external door at location

9 was assumed to be receiving almost the direct effects of the

prevailing west wind, and wind function No. 2 was set at 11 mph

for this purpose. The external doors at locations 6 and 15 were

assumed to be receiving indirect and turbulent actions due to the

west wind. Wind function no. 4 at 8 mph was used for these

locations in the computer simulation. The inner ring doors at

locations 5, 9, 11, and 14 and the external door at location 12 were assumed to be in relatively stagnant areas. Wind function

no. 3 at 5 mph was utilized for that representation.

16

70
TABLE 7. TEMPERATURE AND WIND CONDITIONS

Case

Indoor

Temp.

P F

Outdoor

Temp.

°F

Wind Speed (mph)/

Direction

Function No. 1 - 0 Function No. 2 - ll

Simulated Function No. 3 - 5 Conditions All 74 73 Function No. 4 - 8

Actual

Conditions 1 75 71 8, westerly

2 76 76 11.4, westerly

3 74 75 11.4, westerly

4 74 75 11.4, westerly

5 74 72 10.8, westerly

6 74 73 10.8, westerly

17

71
72

FIGURE

2.

WIND

EFFECTS
Results of Computer Si mulat ions for Calibration

The comparative results between the field-collected pressure

difference data and that produced by the computer model of the

San Diego VA Hospital in the newly developed air movement program

are presented in Figures 3 through 32, except for pressure test case no. 3. Because the model configuration utilized a single

open and connected corridor, no pressure differences were generated between the center core corridor and the outer wing corridors

by the computer simulation. Consequently, no comparative results

were obtained.

The comparative results, in general, are in good agreement. This

implies that the computer simulation model utilized was reasonably

representative of the building and the test conditions at the time

of the field pressure difference collection. The elevator pressure

difference comparisons appeared to be somewhat better than the outside .wind function and external door comparisons. Overall behavior

appeared to be consistent and representative of the actual building

system. Occasional points varied, but there was some uncertainty

about some of the measurements taken, due to fluctuations in the

measuring gages, as well as a wind that rapidly fluctuated between

500 and 1,200 fpm in speed.

19

73
x:

b£) 3

oM

x:

•u H -

• 0 n3 # 25 .H >-i w

X) 4-1 4J • c

_£j

No (Uc

•HO

l/l -P •H Ck

CJ

r-l

• •r{ CO >• o 01 4J

a) Ck bO CO

r—

{

cO X) w <1) U

t—

0) aj

* Ck > xo e <! 4J ri <o in in

1 X <1 1

1*~

H‘ '£>

H

in

^ a) XI

4H

- m M

kiO

O

£

•n o

voo o

rro

roo04o

o

o

04OCOO o

ino

o i i ODuaaajjTa oinss a^a

20

74

FIGURE

3.

SIMULATED

ELEVATOR

SHAFT

NO.

1

VS

SAMPLE

POINT

NO.

(PRESSURE

TEST

CASE

NO.

1)
Pressure

Difference

.07 -

.06

.05

.04

.03

.02

.01

0.00

-.01

-.02

-.03

-.04

-.05

Average line drawn through

shaft No. 3 points

v Sim. Elev. Shaft No. 2 O Sim. Eley. Shaft No. 3

Sample Point No. 2 Average line drawn through

shaft No. 2 points

Floor Number

FIGURE 4. SIMULATED ELEVATOR SHAFTS NO. 2 AND 3 VS SAMPLE POINT NO. 2 (PRESSURE TEST CASE NO. 1)

75
m

TJC

itf

o

E5w

-pm o

fC £5 ui -uc

* M

> o

0) Ck

I—

w o

r—

(

* a 5 t

in in * o

r-oIDo

-<J

<3 S>

<J-xIDO O

m

o

o

o o c

• • • o I g oouaaajjxa amssojd

roo o

H* VO

H

•n

uo

oH

£n

Q

ino

CM

22

76

FIGURE

5.

SIMULATED

ELEVATOR

SHAFTS

NO.

4

AND

5

VS

SAMPLE

POINT

NO

(PRESSURE

TEST

CASE

NO.

1)
oa

co

•H

-PO

Ch vo

ra

c; o

•K a

0) 'O

•rt 01 -Po

w

•P

•r|o

&t

a)

i—

a*

to to X <J

to

»—

ID

H

m

'in

ID -<£h

p

o

o

rH

PH

VO

H

-W

•P o

voo

ino

^3* O

m

o

o

o o c o | I aouojegjTQ ainss sxa

m

o o

ino

23

77

FIGURE

6.

SIMULATED

OUTSIDE

WIND

FUNCTION

4

VS

SAMPLE

POINTS

6

AND

15

PRESSURE

TEST

CASE

NO.

1)
TS

ro

O3

CS

G rH O >-l •H

+JO CO

in m

o • • • • O J I aouajagjxa aanssajjj

24

78

FIGURE

7.

SIMULATED

OUTSIDE

FUNCTION

NO.

3

VS

SAMPLE

POINTS

NO.

b,

8,

11,

12
(NO«

c

o

•HP cn O

§ o

Pm 2! C

•H£

Qi

•riW

•Pao

-Pc

rfo

Pk

(1)

I—

{

aw

x <3 7

7

H

• VO

H

'in

•in

-<}-*-

a

PO

OH

Pm H

-<N

H

-rH

-a o

voo

ino o

roo

<No

o

o

<NOcno o

o I I aouajej^ja bolusso

ino

25

FIGURE

8.

SIMULATED

OUTSIDE

WIND

FUNCTION

NO.

2

VS

SAMPLE

POINT

NO

(PRESSURE

TEST

CASE

NO.

1)
04 ro

O O

2! 2; cm

-P 4J

10 n X X

to to P

C

. . -H > > O

tl 01 ft w w a 5 §

to to to * 0<i

±J 4-1 4-1 4-i CO CO x: -C

CO CO CO •w .3 -C

00 00 -H 3 3 o

O O 1 >4 Pi -C -C CO u 4-1 g g oz

to CO P

X)

Pi T3

ai C0 CD C 4J 3

•H C-H

iH rlrl O

a) a<u

00 00

(0 CM CO Pi u

cu • cu > o > < 25<

Br^

%

'' \

-xf-&

rfT

ereo

voo

ino

•*3* o

coo

rHO

O

o a o | | aouajcajgxa ojnssojj

H• vo

M• in

H

* CO ^

MO

O ^ £

a

roo o

ino

26

80

FIGURE

9.

SIMULATED

ELEVATOR

SHAFTS

NO.

2

AND

3

VS

SAMPLE

POINT

NO

(PRESSURE

TEST

CASE

NO.

2)
O I » I I I aouaaojjTQ aanssaaj

27

81

FIGURE

10.

SIMULATED

ELEVATOR

SHAFT

NO.

1

VS

SAMPLE

POINT

NO

(PRESSURE

TEST

CASE

NO.

2)
m

'O

rtf o

55

n

MooH

28

82

FIGURE

11.

SIMULATED

ELEyATOR

SHAFTS

NO. 4

AND 5

VS

SAMPLE

POINT

NO

(PRESSURE

TEST

CASE

NO.

2)
CN

O

C

c•n

•PO

£

to Ch c - •H O

& s

a) -p 'O c m o

-p a

PO V

1—

B | w w

X o

— VD

r h-» lO

to

H

...

1

— K?

J M /

XT"\ \ \

j —COM

\

V T _

CM

<J CM

H

«—t

1 i -10

O

u

o

o

•H

Pm

fOo o

rHo

H

o

CNo

m

o o

10o

voo o

CO till o

ouaaajgpTa oanssajCcj

29

o>o

83

FIGURE

12.

SIMULATED

OUTSIDE

WIND

FUNCTION

NO.

4

VS

SAMPLE

POINT

NO.

(PRESSURE

TEST

CASE

NO.

2)
o

25

inH

rd

G

<3

x

Sim.

Wind

Functi

A

Samole

Points

No

!

1

1

I

If

1

>t

VO

'i Is 1 4

*

J

A fl X*\

J\ N

mH

VO < 5

M

•in

•in

H^

u

oo

*H

o

voo

ino o

rnoOlo

o

o

H

o

04o o

kj* o

o § | aouaaajjra oanssajj

ino

30

84

FIGURE

13.

SIMULATED

OUTSIDE

WIND

FUNCTION

NO.

4

VS

SAMPLE

POINTS

NO.

6

AND

15

(PRESSURE

TEST

CASE

NO.

2)
xl9

r-\

CN

CO

§

ao

IT;

x

Sim.

Wind

Functi

A

Sample

Points

Nc

1

l ~

3*t’ ‘

—3C

-1-

r4HCM

- r-\ r-J 1, Jft J 2,

\ \

\ S?

j

1 * a

/ /

/ /

/

4

'• \ Y,

i <

COin

1 ^

/ //

'/

3 Y \

\

\i

\

j <

\

J ^

K

\

\

: v. \ c a K I \ v

X

3

m

1 A

* »

O

X r

. \

> \ c 'x\

C >

>

1! j ^ J J

H

^ <D ,Q

$3M

O

O

o

voo

ino o

rooCMOo

o

CMO

o a a aouaaajjxa aanssaa^

coo

nj* o

«

ino

31

85

FIGURE

14.

SIMULATED

OUTSIDE

WIND

FUNCTION

NO.

3

VS

SAMPLE

POINTS

NO.

5,

8,

11,

12

(PRESSURE

TEST

CASE

NO.

2)
ViO.OH

Cm

o i i oouajagrfTa oanssaja

32

86

FIGURE

15.

SIMULATED

ELEVATOR

SHAFT

NO.

1

VS

SAMPLE

POINT

NO

(PRESSURE

TEST

CASE

NO.

4)
CN fO CN O O

& & C* p p

•P <H O

<d d a W W 4JG

• • *H > > O

O O Pi

»H H

w rq flj

•—

{

• • •3WWW.3 §

X Oo

/ /

— VO

7

/

/ /

j.

r

i

i

i

si

e

j //

/

e—-/y

/

/

//

Ul

M

1

1 i 5£/V v s v

—

M

\

X

3 xl ) n

H

s' 7(7) ^

s'

* /

>

r

i

1 W1

1

1

‘TM

M

i j ,

i

i

ii y

- X 1 (. >\

1

l 0

‘"r—

KJ

u

O

O

cH

Ua

o

VDO

m

o o

coo

o

o o o

o i § eouaaajgrpa ajnsso^d

cno o

ino

33

87

FIGURE

16.

SIMULATED

ELEVATOR

SHAFTS

NO.

2

AND

3

VS

SAMPLE

POINT

NO

(PRESSURE

TEST

CASE

NO.

4)
m

'd

o2

n

x

Sim.

Elev.

Shaft

A

Sample

Poi'-t

No. /

- vo

;

/

n

i

i

i

si

e

/

f

/*

/

U]M

n - j

1

— *3*

... , . ^ j \s

H

r/

1

/ N

<2 3

**

— TOM

s

s'

1

"(N

H

2

J

r—

1

— CQ

2

Uo

o

rH

(M

r^* o

VOo

ino o

m

o o

o

o

H

O

(NO m

o o

ino

o 8 8 eouaaajjTa o^nssaaj

34

88

FIGURE

17.

SIMULATED

ELEVATOR

SHAFTS

NO.

4

AND

5

VS

SAMPLE

POINT

NO

(PRESSURE

TEST

CASE

NO.

4)
o

2;G in O

•H

•Pog

*

3

(H VO

*0c

cd

x

Sim.

Outside

Wir

A

Sample

Points

Nc ,/

/

P

/x

/ r

If

-1J

'

’ x

M

* vo

H* in

•in

M*

u ** o

Ua

CQ o

VOo

m

o o

COo

CNO

O

o o

8

CMO

COO o

O g 8 oouaaajjTa a^nsseJcJ

ino

35

89

FIGURE

18.

SIMULATED

OUTSIDE

WIND

FUNCTION

NO.

4

VS

SAMPLE

POINTS

NO.

6

AND

15

(PRESSURE

TEST

CASE

NO.

4)
<N

a

o

aouajcajjxa ojcnssajcj

36

90

FIGURE

19.

.SIMULATED

OUTSIDE

WIND

FUNCTION

NO.

2

VS

SAMPLE

POINT

NO

(PRESSURE

TEST

CASE

NO.

4)
'dG

rt

-s*

i—

O

A

G

O

4JU

m

x

Outside

Wind

Fun

A

Sample

Points

No /

- VO

! 1

H

1

— IT)

,7 /

m

H

rl

rH

fl h

/ ^ n.1. H

// ^ 1-1 % T 1 4 < J ^q ^

0

1

>

J n

H

71 “TJ

H

L

r-H

— CQ

u

V

1

uo

oH

r-ovoo

ino o

m

o

o

o o c o i | eoaoasjjTa einssaid

cno o

ino

37

91

FIGURE

20.

SIMULATED

OUTSIDE

WIND

FUNCTION-NO.

3

VS

SAMPLE

POINTS

NO.

5,

8,

11,

12

(PRESSURE

TEST

CASE

NO.

4)
CN

CM

ri 5, — m ^

cn cr 0

• • 2

0 0

& Z 4JG

• . -H > > O

O ID Pi

r- . H P W ID

r-i

• • cu aWWW5 §

X 0<

V

/

r r\

- vo

/

/ U

/

M

/

! * f

— LO

T /

/

1

i

1

1

l

31

4

-

41

5

1 ^

' J

/

r1

!

<3 * N•> S

< >1T\ J ^ J —ri

M

1 r €

V

'

J ‘“CN

H

\ ,

\, \

‘H

r- v/ 0 cD

3

lO3

•

cr3

•

*>3

• N

3

• H C 3 C•

3 r 3 CH C 3 <

•

N r 3 c0 * 3 <

•

& u* 3 C

— Q

1>

I I aouajajjxa ajnssaxj

38

92

FIGURE

21.

SIMULATED

ELEVATOR

SHAFTS

NO.

2

AND

3

VS

SAMPLE

POINT

NO

(PRESSURE

TEST

CASE

NO.

5)
uooH

ft o

S3

EhZH0

ftw41

01m

— > m O2 02W

01<u 3W EH oj o)

ft. « Eh Os s > D W W

ft to w w QW

Ehas

01

fS

<NDOH

ft

ft I I aouajajjTQ a^nssajta

39
T>a

ton

x

Sim.

Elev.

No. 4 ^

Sample

Point

No. / - VO // M //

/• /

""mH

H / /

<] j X'

M < J ^ Ns- ( mH /s'

x' " <i V

"CMH \r

\„

—

H

—

Q

ncoHh

<n§

tri 3HOwA

CUaintn>

ino

53 W Eh Eh <n

C*jw < ^

ino

53W

in<u o

KOo

ino

**r o mo

(NJ o HO oo

CMOroo o

ino

c/)

P$o

Eh<WS

Eh3|M

in

cn

CM§DOM

tM

e«

aouaaaggxa aanssajd

40

94
R

rJ

3

R

O

O

»—

I

o i I oousaajjxa ainssaja

41

95

FIGURE

24.

SIMULATED

OUTSIDE

WIND

FUNCTION

NO.

4

VS

SAMPLE

POINTS

NO

(PRESSURE

TEST

CASE

NO.

5)
<N6

Od4JO

a

M

O

OH

Cl

souaaajjTa sjnssajj

42

96

FIGURE

25.

SIMULATED

OUTSIDE

WIND

FUNCTION

NO.

2

VS

'SAMPLE

POINT

NO.

(PRESSURE

TEST

CASE

NO.

5)
<

T3C

«a

IN

X

m

o

S3

Vi

<u .Q

MO

O

i—

I

P4

Q

f?<

IN

rH

CO

in

o | | aouajejjTa a^nssaaj

43

97

FIGURE

26.

SIMULATED

OUTSIDE

WIND

FUNCTION

NO.

3

VS

SAMPLE

POINTS

NO
<3

uoo

rH

tn

eouaasjgTa aanssejj

r-l• ozHo

p<wp

Oi3<ww> VO rH • o • z oz ww H < & o S EH w WW « Eh O

EH

W < 2 > p W W P W w a Q P4 W

Eh<Pp3

FJWm

OJ

r,i spoH

Ph

44

98
<1

* O CV

o

voo

m

o o

m

o

<No

o

o

i—

o

CMO

COO o

o I 1 aousJiajjTa aarvssaaj

0

55o

oH

pH

ina

CMO

2

H

55H

O

PiW

P

Pi

in>

o

z

wm

<u

Eh

inw

Eh§

D

inw

w

«

Pi

CO

CMw

Pip

u

H

Cm

45

99
m

'a3 m

oa

a -pc

• *H > o

<u cu

I—

M a) H

e e

•H SJ W W

*0

in in o o o

aouaaajjxa ainssajd

ID

• o

a

w

COu

EhW

W

H

§

D

W

tns

Ai

46

100
CN

Ca

M

a

XIH

32

H

o

oH

aouaaajjTQ smssaij

CTl

o

f>§

D

O

H

fa

47

101

SIMULATED

OUTSIDE

WllJD

FUNCTION

NO.

2

VS

SAMPLE

POINT

NO

(PRESSURE

TEST

CASE

NO.

6)
m

vt*

• a

o «s 55 \o

<D •QE3

S3U

o

oH

En

o I aouaaojjxa oinssoia

48

102

FIGURE

31.

SIMULATED

OUTSIDE

WIND

FUNCTION

NO.

4

VS

SAMPLE

POINTS

NO.

6

AND

15

(PRESSURE

TEST

CASE

NO.

6)
Nr-4

c

10

IN

I—

I—

l—l

N'H

a

o

55 m

zs 2

M

O

O

<—

fa

aouajojjTa eanssoa.-r

49

103

FIGURE

32.

SIMULATED

OUTSIDE

WIND

FUNCTION

NO.

3

VS

SAMPLE

POINTS

NO.

5,

8,

11,

12
SMOKE CONCENTRATION SIMULATIONS

Two sets of smoke cases were simulated on the newly developed air

movement program coupled to the present smoke concentration program.

The first set simulated the field trace gas tests that had been performed earlier. The second set simulated the smoke concentration

of the pressure calibration test cases previously discussed.

Trace Gas Simulations

A total of six trace gas tests were available for comparison w: th

the computer simulation results. These tests are defined as follows

1. Smoke Simulation Test No. 1 - In this case,

the HVAC system was in a normal mode with the

simulated burn room on the third floor.

2. Smoke Simulation Test No. 2 - In this case,

the HVAC system was in a control mode, as follows

a. The south wing of the third floor was

placed on exhaust only and the burn room

was located in this wing.

b. The east, west, and north wings of the

third floor were placed on supply only.

c. The third floor interstitial exhaust fans were turned off except for the south wing.

50

104
d. The balance of the building operated in

a normal mode.

3. Smoke Simulation Test No. 3 - In this case,

the simulated burn room was placed on the

second floor, the second floor interstitial

fans were turned off, and the balance of the

building remained in a normal mode.

4. Smoke Simulation Test No. 4 - In this case,

the simulated burn room was located on the

second floor, the second floor was placed on exhaust only, the third floor was placed on supply only, the third floor interstitial

fans were turned off, and the balance of the

building remained in a normal mode.

5. Smoke Simulation Test No. 5 - This was a smoke decay study with the simulated burn

room shut down, the third floor interstitial

exhaust fans on, and the KVAC system in a normal mode.

6. Smoke Simulation Test No. 6 - This case was

a purging study of the third floor interstitial

space with the trace gas released in the interstitial space and the IIVAC system in a normal

mode.

Computer Simulation of Trace Gas Tests

Since the smoke concentration program did not have the capability

to simulate lateral movement of smoke, very few comparisons could

be made. Further, no capability presently exists to perform decay

and purging simulations which are of interest to designing smoke51

105
controlling HVAC systems. Consequently, cases 5 and 6 and portions

of case 3 could not be simulated.

A very important point must be considered when using the present

smoke concentration program with the newly developed air movement

program. The smoke concentration program does not have the capability to consider all of the infiltration routes provided by the

newly developed air movement program. The newly developed air movement program allows a user to select any two of the external wall

flows from/to the corridor, the floor above/below flows from/to the

corridor and 10 vertical shafts, as a maximum data link to the smoke

concentration. This is the maximum configuration allowed by the

present smoke concentration program.

For this smoke study of the San Diego VA Hospital, the mass flow

data for the six elevator shafts, the shafts adjacent to stairwells

10 and 12, the pneumatic trash/laundry access path, and one stairwell were passed from the newly developed air movement program to

the smoke concentration proqram.

The results of the computer simulations compared to the trace gas

tests are presented in Tables 8 through 22.

Smoke Test No. 1 - The infiltration rate of smoke from the third

floor in the computer simulations of the smoke tests appear to be

occurring at too high a rate. The infiltration of the second floor

interstitial level in the computer simulation of smoke test 1 may

or may not be true. The simulated amount of leakage may be too

high. However, no samples were taken in the second floor interstitial level. The infiltration of the trace gas into the fourth

floor of the first smoke case probably occurred through a path

other than the interstitial spaces, which are usually at a lower

pressure level than the occupancy floors. A good possibility is

that the trace gas was transported by the elevator cages, since

52

106
TABLE 8 . SMOKE SIMULATION COMPARISONS

SMOKE TEST NO. 1 AT 5 MIN.

Floor Corridor Elev. No . 2 Shafts 8/10

Samp. Sim. Samp

Sim. SampSim. Samp. Sim. Samp. S im. Samp. Sim.

B

1

11

2

21 . 028 . 030 .009

3 1.0 1.0 .153 .006

31 .013 .252 .062

4 0.00 . 052

41 .032

5 . 028

51 .020

6 .017

61 .013

53

107
TABLE 9 . SMOKE SIMULATION COMPARISONS

SMOKE TEST NO. 1 AT 20 MIN.

54

108
TABLE 10. SMOKE SIMULATION COMPARISONS

SMOKE TEST NO.AT 35 MIN.

55

109
TABLE 11. SMOKE SIMULATION COMPARISONS

SMOKE TEST NO. 1 AT 60 MIN.

Floor Corridor Elev. No. 2 Shafts 8/10

Samp. Sim. Samp. Sim. Samp. Sim. Samp. Sim. Samp. Sim. Samp. Sim.

B

1

11

2

21 .101 .228 .051

3 1.0 1.0 .355 .051

31 . 040 .783 .295

4 . 026 .295

41 .221

5 .221

51 .176

6 .176

61 .145

56

110
TABLE 12. SMOKE SIMULATION COMPARISONS

SMOKE TEST NO. 1 AT 10 MIN.

57

111
TABLE 13. SMOKE SIMULATION COMPARISONS

SMOKE TEST NO. 2 AT 30 MIN.

58

112
TABLE 14. SHORE SIMULATION COMPARISONS

SMOKE TEST NO. 2 AT 40 MIN.

59

113
TABLE 15. SMOKE SIMULATION COMPARISONS

SMOKE TEST NO. 3 AT 5 MIN.

60

114
TABLE 16 . SMOKE SIMULATION COMPARISONS

SMOKE TEST NO. 3 AT 15 MIN.

61

115
a ABLE 17. SMOKE SIMULATION COMPARISONS

SMOKE TEST NO. 3 AT 20 MIN.

Floor Corridor Kiev. No. 2 Shafts 8/10

Samp. Sim. Samp. Sim. Samp. Sim. Samp. Sim. Samp. Sim. Samp. Sim.

B

1

11 .005

2 1.0 1.0 .494

21 .105 .567 .068 .284

3 .267

31 .167

4 .159

41 .115

5 .111

51 .086

6 . 002 . 000 .083

61 .067

62

116
TABLE 18. SMOKE SIMULATION COMPARISONS

SMOKE TEST NO. 3 AT 30. MIN.

*Decay process cannot be simulated in the

Smoke Concentration Program at present.

63

117
TABLE 19. SHORE SIMULATION COMPARISONS

SMOKE TEST NO. 4 AT 5 MIN.

64

118
TABLE 20. SMOKE SIMULATION COMPARISONS

SMOKE TEST NO. 4 AT 15 MIN.

Floor Corridor Shafts 8/10

Samp. Sim. Samp. Sim. Samp. Sim. Samp. Sim. Samp. Sim. Samp. Sim.

B

1

11

2 1.0 1.0

21 . 012 .530 .245

3 . 000 . 000 .217

31 .130

4 .119

41 .083

5 .077

51 . 058

6 . 000 .000 . 055

61 . 043

65

119
TABLE 21. SMOKE SIMULATION COMPARISONS

SMOKE TEST NO. 4 AT 25 MIN.

Floor Corridor Shafts 8/10

Samp. Sim. Samp. Sim. Samp. Sim. Samp. Sim. Samp. Sim. Samp. Sim.

B

1

11

2 1.0 1.0

21 . 006 .695 .350

3 .000 .000 .334

31 .211

4 .204

41 .148

5 .145

51 .113

6 .000 . 000 .111

61 .089

66

120
TABLE 22. SMOKE SIMULATION COMPARISONS

SMOKE TEST NO. 4 AT 35 MIN.

67

121
10 of them were in continual operation. However, the computersimulated leakage shown in elevator shaft no. 2 is a distinct

possibility. Leakage was also evidenced back to the corridors

from the fourth floor upward in the newly developed air movement

program but not by the smoke concentration program. It is the only

elevator shaft connecting with the interstitial spaces. Shafts 8

and 10 represent the shafts adjacent to stairwells 10 and 12.

This infiltration of these shafts is possible through small penetrations in the interstitial spaces, which is evidenced in the

computer simulation data.

Smoke Test No. 2 - The infiltration rates of the computer simulation again appear to be much too high in comparison to the trace

gas test results. With the exception of the magnitude of the

concentrations, the behavior of the simulated infiltration com- pared favorably to the trace gas test for those sample points which

could be compared. However, the computer simulation evidenced

significant infiltration of the elevator shafts and the corridor

spaces below the third floor. The elevator shaft infiltration is

reasonable, but the corridor infiltration may be due to unrealistic

leakage paths in the computer model between floors and the interstitial levels immediately below. The only actual penetrations

in this direction are for drain lines, and they are reasonably

well sealed. Hence, the infiltration to the simulated floor due

to interstitial leaks may not be realistic. The shafts adjacent

to stairwells 10 and 12 again reflect smoke infiltration.

Smoke Test No. 3 - The computer simulation evidenced the same behavior as reflected in the trace gas test. However, the

rates of infiltration are much too high as compared to the

68

122
trace gas test. Evidence of the trace gas on the sixth floor in

the trace amount at 2 0 minutes was not found in the computer simulation and was probably due to transport by the 10 elevator cages.

Typical infiltration of elevator no. 2 and shafts 8 and 10, as evidenced in previous cases, occurred in the computer simulation

again. The decay process from 30 minutes onward could not be simulated in the smoke concentration program, as indicated earlier.

Smoke Test No. 4 - The computer simulation reflected the same behavior for those points which could be compared as did the trace

gas test. However, the concentrations were again much too high

and were probably due to overly large infiltration rates. Shafts

8 and 10 again reflected the same infiltration characteristics,

via entry from the interstitial space. An important point is

that these shafts communicate with the wing interstitial spaces

via plumbing and electrical conduit penetrations which provide an infiltration path to all interstitial spaces.

The field trace gas test data for smoke test 4 also provided two

pressure difference measurements which can be compared to the

computer-simulated results. These differences were measured on the second and third floors between the corridor and an elevator

shaft. The field data did not specify which elevator shafts were

measured. Consequently, Table 23, which reflects a comparison of

the measured and computed results, presents the results from each

elevator shaft determined by the computer simulation, in comparison with the field data. The comparison is favorable and indicates that the elevator shaft pressures in the computer simulation

may have been about .01 inches of water too high in pressure.

65

123
TABLE 23. SMOKE TEST NO. 4 - PRESSURE COMPARISONS

Floor Measured Computer Simulation

Elev.

No. 1 Elev.

No. 2 Elev.No. 3

Elev.

No. 4 Elev.

No. 5

2 -.02 -.012 -.006 -.013 -.013 -.013

3 + .02 .031 .037 .030 .030 .030

Note: Minus indicates flow from the corridor to the

elevator shaft; plus indicates the converse.

70

124
In general, the San Diego VA Hospital is well sealed around cables,

conduits, and pipe. However, occasional points of leakage exist

because of incomplete sealing at these penetrations. More significantly, there are numerous electrical conduits that exist and

that are well sealed at their wall penetrations. However, those

conduits are unused. They provide 4- to 6-inch diameter holes

through the barriers and are significant paths of infiltration.

The behavior of the computer simulations paralleled the results

of the field tests, except in the levels of concentration, and

the computer simulation appears suitable for predicting the behavior of smoke in the San Diego VA Hospital.

71

125
Computer Simulation of Smoke Movement on Pressure Tests

As indicated earlier, smoke concentrations were also simulated

on the computer programs for the pressure test cases. These

cases also synthesized various realistic modes of operation under

v/hich the building system could exist during a fire.

Pressure test case no. 1, with a burn room on the third floor, was

identical to smoke test no. 1 and will not be repeated. However,

pressure test case no. 1 was also run with a simulated fire in the

first floor interstitial level. At 60 minutes, the only infiltration calculated was into stairwell 12, with concentrations of .007

at the second floor level and .118 at the second floor interstitial

level of the stairwell.

Pressure test case no. 2, with a fire on a pressurized floor, the

third floor, in this case, demonstrates the infiltration v/hich

could occur under such a condition. Table 24 presents the results

from the smoke concentration program. As should be expected , the

elevator shafts provide the primary infiltration paths to the occupancy floors.

Pressure test case no. 4 simulates a fire on the third floor, with

the third and fourth floors in a control mode. Results from the

smoke concentration program evidenced no infiltration at 60 minutes

to any space represented in the input generated by the newly developed air movement program, as defined above.

72

126
TABLE 24. SMOKE SIMULATION COMPARISONS

SMOKE TEST NO. 2 AT 60 MIN.

73

127
Pressure test case no. 5 simulates a fire on the third floor,

with the second, third, and fourth floors in a control mode.

Results from the smoke concentration program evidenced no infil

tration at 60 minutes to any space, in the same manner as pressure test case no. 4, above.

Pressure test case no. 6 simulates a fire on the fifth floor,

with the fourth, fifth, and sixth floors in a control mode.

Results from the smoke concentration program evidenced no infil

tration at 60 minutes to any space, in the same manner as pressure test case no. 4, above.

Simulation of a fire on the third floor, while in a control

mode on the fourth, fifth, and sixth floors, was performed as

a variation on pressure test case no. 6. With the exception of

the shafts adjacent to stairwells 10 and 12, no infiltration of

the upper floors above 31 occurred. This is to be expected be- cause of the shielding action of floor 4 in a pressurized mode.

Infiltration by two routes was evidenced to the lower floors.

Infiltration by f loor-to-floor leakage and by elevator shaft

no. 2 to the lower floors occurred in the computer simulations.

The results of the smoke concentration program are shown in

Table 25 for this case.

The results evidenced in the computer-simulated behavior of the

smoke v/ere realistic and occurred as expected for the given

conditions for these cases.

74

128
TABLE 25. SMOKE SIMULATION COMPARISONS

SMOKE TEST NO. 6 A AT 60 MIN.

Floor Corridor Shafts 8/10

Samp. Sim. Samp. Sim. Samp. Sim. Samp. Sim. Samp. Sim. Samp. Sim.

B

1

11

2

21

3

31

4

41

5

51

6

61

. 001

.102

1.0

.733

.063

.189

.190

.190

.052

. 052

.282

.282

.211

.211

.169

.168

.136

i

75

129
PARAMETRIC ANALYSIS

The performance of a parametric analysis, unlike a sensitivity

analysis, need not be an exhaustive analysis of the effects of

incremental variations of each independent variable over an interval of variation. It usually comprises meaningful, i.e., re- alistic, variations and combinations of variations of significant

independent variables. However, its upper limit is equivalent

to an exhaustive sensitivity analysis. In the case of a building

as extensive as the San Diego VA Hospital, the number of potential

variations of state of the building/HVAC system are quite large.

Since the primary objective of this effort was to demonstrate

the practical application of computer simulation methodology to

the design, analysis, and evaluation of smoke control features

of large buildings, and since a very limited amount of time and

funds could be allocated to this building, it was necessary to

define a set of parametric states of the building/HVAC system

that were few in number but would clearly fulfill the objectives.

In addition to the above considerations, the investigators responsible for this project nave been . extremely interested in evaluating

the effects of various energy levels and sources which could operate against smoke control measures in buildings. It was felt that,

if realistic energy sources and levels could be induced in the

simulation and reflect significant effects upon the smoke control

measures, then the value of such simulation would be demonstrated.

It was noted during a fiexd trip to the hospital that, during the summer months, there was a prevailing west wind off the Pacific

Ocean. The implications of its effect upon the interstitial spaces

posed an interesting problem. Consequently, these investigators

established two fire scenarios which have realistic sources and

spaces according to the nation's statistics on fire sources. These were defined as follows:

76

130
1 . A fire in the third floor electrical room

adjacent to the shaft next to stairwell 9 with subsequent HVAC failures in the third

floor. This was followed by a control

mode at normal weather conditions.

2. A fire in the third floor interstitial

space with subsequent equipment failures

in the west wing of the third floor interstitial level. This was followed by a control mode at nominal weather conditions

and a control mode with a west wind of

25 mph.

Normal HVAC states were also run with both of the simulated fires.

The detailed conditions for the results of the computer simulations

are presented in the following material.

Scenario I

The San Diego VA Hospital has electrical and plumbing shafts that

exist adjacent to stairwells 9 and 11. Both of these shafts have

independent air supply fans on the sixth floor interstitial level.

They are vented to the outside periodically down an external wall

and have many penetrations at each interstitial level where an electrical room exists. These electrical rooms open directly onto

the plumbing and cable shafts. The air supplies mentioned above

are actually for these electrical rooms.

An electrical fire is assumed to occur in the electrical room at

the third floor interstitial level. Before it is suppressed, it

is assumed to destroy sufficient electrical circuitry to cause

the third floor interstitial fans, the third floor exhaust fans,

and the air conditioning units in the third floor interstitial

space to fail. The exhaust fan TF8 for the core in the penthouse

was assumed to continue operation.

77

131
Three computer simulations were made to evaluate the effect of

such a condition with a nominal temperature state and a nominal

wind velocity of 11 mph. The first case. Case 1A, simulated the

effects of a fire state with the third floor HVAC equipment in

a failure mode and the balance of the building's HVAC system

operating in a normal mode. The second case. Case IB, simulated

the effects of an HVAC control mode in effect using the remaining

systems that would be still operational. The control mode was

defined as follows:

1. The third floor and third floor interstitial systems were assumed to remain in a failure state

2. The supply fan to the shaft and the electrical

rooms was turned off

3. The entire fourth floor was placed on supply only

4. The entire second floor was placed on supply only

5. All of the second floor interstitial fans were

turned off.

To provide a base for comparison, the same fire state was assumed

to occur with no failures of the HVAC system in Case 1C.

Case 1A - Failure State of Third Floor HVAC Equipment - The results

from the smoke concentration program simulation of the failure

state indicated that the smoke from the electrical room fire on the

third floor moved downward through shaft no. 9 to the basement

level. Since all of the electrical rooms along that shaft open

directly onto shaft no. 9, this implies that the smoke detectors

below the fire in the lower electrical rooms would also have been

activated. Some ambiguities as to exactly where the fire source

is located might occur, if heavy dependence is placed upon combustion

78

132
product detectors. The heat detectors present in the electrical

rooms might prevent such a problem, but they are slow-reacting

sensors by nature.

The smoke from the shaft infiltrated the second floor center core

interstitial space and the basement corridor. The second floor

interstitial smoke then infiltrated shafts 8 and 10. These were

the only results directly predictable from the present smoke concentration program. A great deal more significant infiltration

actually occurred. In order to trace the flow of smoke more completely, the air flow paths were traced from the results of the

newly developed air movement program.

Tracing the flows from the spaces infiltrated according to the

smoke concentration program, the results were as follows:

1. The smoke in the center core of the second floor

interstitial level infiltrated all of the wings

of the second floor interstitial at low levels

to the already infiltrated shafts 8 and 10. The

balance of the smoke was exhausted to the outside.

2. Fifty percent of the smoke infiltrating the basement corridor was then moved to the office spaces

and the balance exhausted to the outside. This was then mostly exhausted. Trace amounts would

have infiltrated two stairwells.

3. Shafts 8 and 10 infiltrated the first floor interstitial space and the south wing of all of the

interstitial levels above the second floor. These

spaces then leaked to adjacent wings and other

vertical paths in small amounts. The flow of smoke

indicated by the newly developed air movement program under the prescribed failure conditions is

79

133
illustrated in Figures 33 through 35. All of

the infiltration paths are not shown. Higher

order flow paths are generated by the infiltration of the plumbing risers and the stairwells. The infiltration from these spaces is

almost entirely into the interstitial spaces

above the fourth floor interstitial level.

Analyzing the results of the newly developed air movement program

indicated that the third floor was approximately .015 in. of water

below normal pressures, with:

1. The west wing providing a large amount of air

to the corridor

2. The north and south wings supplying small amounts

of air to the corridor

3. The corridor supplying a large amount of air to

the east wing, with the balance exhausting through

TF-3

4. The elevator shafts .01 to .02 in. of water above

the corridor pressures of the third floor and small

amounts of air moving from the elevator shafts to

the third floor corridor.

The center core of the third floor interstitial space with the

north and south wings was fairly static. Most of the air supply

was from the third floor and was mostly exhausted by the outside

vents. The east wing of the third floor interstitial received

significant air from the third floor east wing and exhausted it

to the outside. About 100 percent of the air exhausted from the

80

134
FIGURE 33. PRIMARY SMOKE ROUTES AT THE 31 LEVEL

(CASE 1A)

81

135
FIGURE 34. PRIMARY SMOKE ROUTES ON THE THIRD FLOOR

(CASE 1A)

82

136
i

JOpTX -aoo

L * °N

*330

9^03

MM

Hd

MS

MS

MN

w a, •H M 3

<D tJ1 w .—, W

in '

»—1

rH nj t—I o C a) •H •H Ss ,o M P F •H O p (U <D *—1

-P

r—1

A* COw

H II II

cu

w& n

cnw

tHDO

PiHO3uHH

piw>

>i

piM

Pi

P.

w

CO<u

innW

PiDOH

83

137
west wing of the third floor interstitial was to the west wing of

the third floor. The air supply to the wing of the third floor

interstitial space was outside air.

From the fourth floor upward, the building was essentially at a normal state in the corridors and compartment spaces.

This case illustrates the value of the newly developed air movement program in analyzing potential failure states. It also provides a means to analyze evacuation plans, e.g. , infiltration of

the third floor east wing from a fire in the west wing of the

third floor interstitial space.

The assumption of total failure of the equipment of the third

floor interstitial level due to the single electrical room fire

is not realistic in the case of this building. Only the west

and north wing interstitial equipments would probably fail. However, the basic flow behavior would remain the same, with the

exception of the east wing third floor infiltration. The third,

south, and center core supply fans would probably still be operational and cause exhaustion through the north or west wing

interstitial levels, depending on the wind velocity. However,

there would also be the possibility of additional equipment

failures at higher levels in the west and north wings if such a fire occurred.

Case IB - Control Mode - The control mode defined above for the

given failure state was simulated with this case. The smoke

infiltrations predicted by the present smoke concentration

program failed to provide a comprehensive view of the effects

of this control mode and detailed analysis of the flow predicted

by the newly developed air movement program was necessary.

84

138
The limited results of the smoke concentration program indicated

the following:

1. Infiltration of the first and second interstitial levels from shaft no. 7 occurred.

2. Secondary infiltration of elevator no. 2 From the interstitial spaces occurred.

3. Infiltration of shafts 8 and 10 adjacent

to stairwells 10 and 12 occurred.

4. Infiltration of the shaft adjacent to

stairwell no. 11 at the lower levels

occurred.

In this instance, the smoke infiltration shown by the smoke

concentration program did not accurately reflect the flow of

smoke from shaft no. 7. An analysis of the air movement simulation data indicated that the smoke flow paths were as shown

in Figure 36. The control mode, as simulated, appears to be

effective. Although the smoke enters the interstitial spaces

and a plumbing riser, it never enters the occupancy floors and

always results in being exhausted to the outside.

This case illustrates the value of simulated air movements to

analyze the effectiveness of HVAC control of smoke movement.

It also illustrates the serious deficiencies existing in the

present smoke concentration program and the hazards of employing

it in combination with the newly developed air movement program.

85
r^Outside Vent

r->11 Core

—>41 W.Wing->N. Wing-

^S. Wingr-*E. Wing_

kExhaust Fans

-Plumbing Riser—

-^Exhaust

f->4l N . Wing >E. 41 E.VJing

—>41 N.WingExhaust

“>N. Wing-

—>51 W.Wing--^5. Wing.

Shaft 7-1 L^Exhaust

->51 N.WingE. Wing-

-*Exhaust —^Outside Vents

>N. Wing-|

->S. WingJ" —>61 W.Wing-

>Exhaust

*-^6I N.Wing—»E. Wing41 S. Wing >£. L^5I All Wings-»E.

->E. Wing >Exhaust

-^Exhaust

->E. Wing >Exhaust

-^Exhaust

->E. Wing ^Exhaust

-^Exhaust

FIGURE 36. SMOKE FLOW IN CONTROL MODE

(CASE IB)

86

Wing-

^Exhaust

Wing.

Wing—>Exhaust

140
Case 1C - No HVAC Failures - This case assumes that the fire

exists in the electrical room as for the previous cases and

that the HVAC system is in a normal state. The smoke concen- tration program indicates smoke infiltration as follows:

1. Infiltration of the basement, the first floor

interstitial level, and the second floor interstitial level

2. Secondary infiltration of elevator shaft no. 2

3. Infiltration of shafts 8 and 10

4. Infiltration of the shaft next to stairwell 9.

An analysis of the actual flows indicates routes similar to

that shown in Figure 36, except for possible infiltration to

the basement. The normal state appeared to be almost as effective as the control mode in routing the smoke to exhaust

areas for the fire simulated in the electrical room.

87

141
Scenario II

In this evaluation, it is assumed that the HVAC equipment failed

because of fire in the west wing of the third floor interstitial

space. 'Phis condition implies the failure of the exhaust fan for

the west wing of the third floor interstitial and the supply and

exhaust systems for the west wing of the third floor. This failure state was simulated in the first case. Case 1A. A control mode

was established in the second case. Case IB, where:

1. The remainder of the third floor was placed on

supply only

2. The remainder of the third floor interstitial

exhaust fans were turned off

3. The fourth floor was placed on supply only

4. The second floor interstitial exhaust fans were turned off

5. The second floor was placed on supply only

6. The prevailing west wind was assumed to be

at a nominal speed of 11 mph.

The same control mode was also simulated with the west wind at

25 mph for a third case. Case 1C.

A normal mode with the same smoke source was simulated with the

wind at a nominal 11 mph for the fourth case. Case ID.

88

142
Case 2A - Failure State of the VJest Wing HVAC Equipment - The results from the smoke concentration program indicated no infiltration through corridors, vertical shafts, or corridor to corridor.

However, tracing the air flows shown by the results of the newly

developed air movement program indicates significant air movement

from the west wing of the third floor interstitial where the smoke source was assumed to exist. The primary paths of the smoke from

the vest wing of the third floor interstitial space are illustrated

in Figures 37 and 38. The smoke, routes to several levels of infiltration are shown in Figure 39. The flow movement indicates significant infiltration of essentially the entire third floor.

Case 2B - Control Mode at Nominal Wind Speed - An analysis of the

air movement data generated by the newly developed air movement

program indicated that the control mode imposed on the failure

state established in Case 2A, as simulated in this case, effectively routes the smoke through non-occupancy spaces. It does,

according to the simulation, infiltrate most of the interstitial

spaces, but it is either vented or exhausted oy exhaust fans to

the outside. A few stair-wells appear to be infiltrated from the

interstitial spaces in relatively small amounts. The smoke routes,

to several levels of infiltration, are shown in Figure 40.

The present smoke concentration program does not have the ability

to simulate the spaces simulated by the newly developed air movement program. Consequently, it reflected no infiltration of smoke

in its results.

Case 2C - Control Mode with a 25-mpn West TJind - The same control

mode defined earlier for the failure state and simulated in Case 2B was repeated in this case, except that the speed of the west wind

was increased to 25 mph. Although a wind of 11 mph did not affect

89

143
I

FIGURE 37. PRIMARY SMOKE ROUTES ON THIRD-FLOOR ’’NTEP^ITIAL LEVEL90

144
FIGURE 38 PRIMARY SMOKE ROUTES ON THIRD FLOOR
-^W.Wing

3rd Floor

^N.Wing 31

^Corridor 3rd Floor

-^Plumbing Riser——30)

^JE.Wing ^Exhaust

->Shaft 10

^Exhaust

W. Wing 31.

$>^S.Wing 31

—Stairwell

-ws. Wing ^Exhaust

*>Exhaust

f^Shaft 8/10

L

*N.Wing‘

—f*->Pluinbing Riser

—>21 N.Wing-r>Exhuast

L^E.Wing >Exhaust

—>21 E.Wing-

>11 Center— *. Wing—-s-SExhaust

>S.WingExhaust

.^Exhaust

->Exhaust

HExhaust —>21 S .Wing-4^E. Wing ^Exhaust

>Exhaust —>31 N . Wing-? "*E . Wing

>Shaft 10 >© —>31 E.Wing—>Exhaust

r>Stairwell —$31 S . Wing |->E . Wing >Exhaust

l^Exhaust

r*E . Wing * Exhaus t 41 N.Wing'H^Exhaust

I—>41 E.Wing >Exhaust

FIGURE 39. SMOKE FLOW PATHS FROM WEST WING 31

92

146
W. Wing 31- (Continuec

“Plumbing Riser

(Continued)

—*51 N.Wing-

~*4I S.Wing-

->5I E. Wing.

—>51 S . Wing-

-1

-> Center—31-

haft 8/10-

~^LI Center

-—>21 S.Wing ~>31 S.Wing —*11 S.Wing —>41 W. Wing —>51 S.Wing —>61 W.Wing

—^61 S.Wing

Stairwell.

*E.Wing

^Exhaust

texhaust

sL'xhaust

«. Wing ^Exhaus t

.Exhaust

lE.Wing* ^Exhaust

HExhaust

"*11 Center —%I W.Wing —^41 W.Wing —>51 w. Winer

_^6I W.Wing

FIGURE 39. Sr40KE FLOW PATHS FROM WEST WING 31 (Cont.

)

93

147
Corridor 3.

FIGURE

fa. Wing 3

' ^Pneumatic System

}4n. Wing 31— Mg)

-^Exhaust

*. Wing 3-

»S. Wing 3-

>)Pneumatic System

*. Wing 31 MD

^Exhaust

^Pneumatic System

>S. Wing 31 MD

4Elev. No.

-?Elev. No.

X2

*

*Corr. Basement

VEorr. 2nd Floor

*Corr. 4th Floor

^Corr. 5th Floor

^Corr. 6th Floor

^Outside Vent

4LI Center

-)2I Center

-)3I Center

41 Corr.

»4I Center

-»5 Corr.

451 Center

>6 Corr

.

^61 Center

-Exhaust

-421 Center

-^31 Center

39. SMOKE FLOW PATHS FROM WEST WING 31 (Cont.)

94

148
31 W . WingX

^Outside Vent

—> Stairwell 10 ^External Leaks

>11 Center —^Exhaust

31 Center0—4shaft 10-

"^11 Center—^Exhaust

:>Exhaust —Ml N.Wing-d

4E.Wi.ng Exhaust

^1 E.Wing

^—^51 N. Wing-5

‘E.Wing ^Exhaust

^Exhaust —>51 E.Wing—^Exhaust

^E.Wing—^Exhaust —

)

6 I N.Wing-)

^Exhaust

61 E.Wing—^Exhaust

r>Shaft 10-

>21 Center

L»Exhaust

Shaft 8

-

*€>

rfShaft 10-

931 Center

UExhaust

-*£>

©- 41 W. Wing 30

r*E.Wing

-Ml N.Wing *^Exhaust

-^41 E.Wing-

>41 Center

^Exhaust

Exhaust

)E . Wing »Exhaus t -M I S.Wing 5

4Shaft 10-

^Exhaust

^Exhaust

FIGURE 40. INFILTRATION ROUTES UNDER CONTROL MODE

(CASE 2B)

95

149
<p—>Shaft 8 (Cont.

)

Exhaust

->S . Wing

(5)Jl^ 4I W.Wing*

-fWing

^Exhaust

^Exhaust

-^Plumbing Riser

-^Stairwell

.Wing ^Exhaust

-=}N.Wing-—

LjE:

N. Wing*

^Stairwell 3/4 - ->Shaft 10 30

-^Flumbing Riser

:xhaust

^External Leahs

© *'>E . Wing-

—Exhaust

"^Stairwell 12

—t8I Center—KQ)

-*Shaft 10 —9©

-^Plumbing Riser

—Stairwell 5/6—External Leaks

*31 Center ^(5) L—^ s.Wmg- * Stairwell 11- ~il Center

-^41 W.Wing-^>(B)

-^61 W.Wing

—Exhaust

-)Shaf t 8 -c

-^Plumbing Riser

-?E.Wing ^0

-^Outside Vent

FIGURE 40. INFILTRATION ROUTES UNDER CONTROL MODE (Cont.)

(CASE 2B)

96

150
the control mode, as indicated in the results of Case 2B, an analysis of the newly developed air movement program results of

this case evidences a serious change in the flow of smoke with a 25-mph west wind. The flow of air into the west wing of the third

floor interstitial space was in excess of 4,000 CFM and an increase

in pressure in excess of the third floor west wing pressure occurred

because of this increased wind velocity. This resulted in a significant infiltration of the west wing of the third floor, as illustrated in Figure 41. Additionally, extensive infiltration of the

interstitial spaces and low-level, but extensive, infiltration of

stairwells was evidenced, as shown in Figure 42.

This simulation is relevant to the control mode and the failure

state synthesized in Scenario I. Similar results would be ex- pected from the control mode used in Scenario I if the wind velocity were increased to 25 mph. It is important to note that the

simulation of a 25-mph west wind does not mean that the results

evidenced in the computer simulation will actually occur at a wind

of 25 mph. It means that, at some wind velocity higher than 11 mph,

behavior evidenced in the computer simulation will occur in the

real situation.

'‘.‘his case illustrates the need to consider energy levels and sources which may operate against HVAC control techniques under relatively

normal conditions, i.e., in relatively low-energy situations, and

the need for thorough analysis of smoke control techniques. It

also illustrates the potential impact that such conditions would

have on evacuation plans. It further illustrates the value of

computer simulation techniques in analyzing smoke control techniques.

The conclusions that can be drawn from this case relative to the

San Diego VA Hospital are that measures should be considered which

prevent the increase of pressure due to external wind pressure if

97

151
FIGURE 41. THIRD-FLOOR SMOKE ROUTES (CASE 2C)

98

152
*Shaft 10 ®

31 W.Wing-

-j3rd Floor_

W. Wing

">3I Center-%

(Shaft 8-

Hlutside Vent —^Corridor.

~*3I Center

-V2I Center

-JN.Wing

->£. Wing

->3I N.Wing

-^Center Off ^

->3I E.Wing

"^31 Center

.^Exhaust

-3Elev. No. 1 _)Exhaust/Vents

•—^Pneumatic Tube Path —^Basement Corridor-

-^I Center- —>21 Center-

>1 W.Wing- —>31 Center- —>31 S.Wing*

"^Basement Office Space

-plumbing Riser

-ipxhaust —^Exhaust —^Outside Vent

“Xnd Floor W. Wing

Wing

-^>. Wing —^Outside Vent

“Exhaust

I CenterP^Jutside Vent

4^ Wings

-/4 th Floor W.Wing

I W.Wing- —>41 S.Wing

-jExhaust —^Exhaust

FIGURE 42. INFILTRATION ROUTES UNDER CONTROL NODE

(CASE 2C)

99

153
©

31 W. VJing

(Cont .

)

"^51 Center.

^I W.Wing*

"^Outside Vent

^"Hjings

->5th Floor W. VJing

> ^Exhaust

4

-^61 S.Wing-

^61 Center-

—^Exhaust

r-y)utside Vent

_^jings

”^6th Floor W.Wing

-*I W.Wing-

->6I S.Wing-

-^Exhaust

—^Exhaust

V

Gtairwell 10-

"^External Leaks

-^1 W. VJing

-551 W.Wing

>

*->6I W.Wing-

~^4th Floor W.Wing

-^Exhaust

-95 th Floor W.Wing

4- Exhaust

->6th Floor W.V/ing

-^Exhaust

FIGURE 42. INFILTRATION ROUTES UNDER CONTROL MODE (Cont.)

(CASE 2C)

100

154
-^Plumbing Riser

-^N. Wing31 W. Wing—

<4

£

-)3 1 Center—

stairwell 9

-JShaft 10-

-jgtairwell 9-

2

-^Stairwells 3/4-

-^Exhaust

41 N.Wing-

>51 N.WingC

. Wing

xhaust

"^E. Wing

-96 1 N.WingL3Exhaust

Wing ChaustWi]

hai

-^1 N.Wing

>41 E.Wingp^E. VJing

l-^Exhaust —^Exhaust

E. Wing

-361 N.Wing-

-»I E.Wing-

-96 I N.Wingchaust

-^Exhaust

-7E.Wing

>61 E. Wingexhaust

-^Exhaust

[^External Leaks

^E . Wing

>41 N. Wingexhaust

^E. Wing

>51 N.VJingN.Wingl>Exhaust

^E. Wing

-^Exhaust

FIGURE 42. INFILTRATION ROUTES UNDER CONTROL MODE (Cont.)

(CASE 2C)

101

155
31 W. Wing

(Cont. )

'

©

—^N. Wing

(Cont.

)

r*I Center~*£> r*outside Leaks

<¥> l*E.Wing»* ^Stairwell 12—

-MI E. Wing

->5I E. Wing

_y>I E.Wing

^Bhaft 10 -^0

-plumbing Riser

"^4 1 E.Wing

c/ “$5I E.Wing

-^Stairwells /S-^6I E_ Mi

-^Exhaust

—^31 Center-^© F*ll S.Wing

'>51 S.Wing

—^Stairwell 11 >61 S.Wing

-^External Leaks

—>S. Wing- ^External Leaks —^Stairwell %-V*4I S . Wing

"*5I S.Wing —^E.Wing )© -)6I S.Wing

^External Leaks —^Exhaust

Exhaust

-Exhaust

FIGURE 42. INFILTRATION ROUTES UNDER CONTROL MODE (Cont.)

(CASE 2C)

102

156
failure of the interstitial exhaust fans occur. This could be

accomplished by dampers over the outside vents which close in case of fire and exhaust fan failure in that space, i.e., each

wing or center spaces.

Activation could also be established from wind velocity on the

vents of the particular interstitial space suffering from equipment failure and fire.

It is also of importance to note that the present smoke concen- tration program reflected no infiltration of smoke to any spaces

treated in its simulation.

Case 2D - Normal HVAC State - This case simulates the fire condition in the west wing of the third floor interstitial space with

the HVAC system in a normal operating state and at a wind velocity

of 11 mph, i.e., without a failure state of the equipment in the

west wing of the third floor interstitial space.

The results of the smoke concentration program indicate no infiltration, except for shafts 8 and 10, which do not provide paths

to occupancy floors.

An analysis of the air flows predicted by the newly developed air

movement program also indicates flow to shafts 8 and 10 as well

as into the north and south wings of the third floor interstitial

space. These two wings then leak to the east wing of the same

level. The east wing exhausts all of its air through its exhaust

fan.

This case implies that, if no equipment failures occur on the

third floor interstitial level, the normal HVAC mode effectively

constrains the smoke to the interstitial level.

103

157
CONCLUSIONS

Results of the computer simulations for the calibration cases,

the trace gas simulations, and the parametric analysis cases indicate that the newly developed air movement program can be

used in an effective operational manner satisfactorily.

The only deficiency encountered with the newly developed air

movement program was an insufficiency of blower or fan representations. At some time in the future, the program should

be modified to allow 50 different fans or blowers.

The use of the present smoke concentration program was essen- tially valueless. Its limitation to 100 corridors and 10

vertical shafts prevents the consideration of the lateral

flows and vertical flows between occupancy spaces. Further, it

cannot represent purging or decay processes, i.e., the negative

concentration process, or compartment spaces. In determining

the smoke flow routes in the parametric analysis cases, it was necessary to manually analyze the flows generated by the newly

developed air movement program. Although the routes could be

established, estimates of the concentrations which would provide

insight into the seriousness of the infiltrations was lacking.

Consequently, the smoke concentration program should be modified to be compatible to the building configurations representable by the newly developed air movement program. Further,

that the smoke concentration program should be modified to

allow the prescription of an initial smoke concentration state

and calculation of a negative or decrementing process to simulate purging and decay of smoke concentrations.

104

158
If further simulations of the San Diego VA Hospital are made, the

model should be modified to separate the wing corridors from the

outer core corridors. This can be accomplished by representing

the wing corridors as compartments. The cases simulated in the

parametric analysis effort imply that the San Diego VA Hospital

offers an extensive base for studying, via computer simulation,

the use of HVAC control of smoke under a variety of conditions,

particularly energy levels.

105

159
REFERENCES

1. D. Sander, A FORTRAN IV Program to Simulate Air Movement in

Multi-Story Buildings .

2. G. T. Tamura and J. H. McGuire, "Smoke Movement in HighRise Buildings," National Research Council, Division of

Building Research, Building Digest CBD , 133, Ottawa, 1971.

106

160
NBS-1 14A (REV. 7-73)

U S. DEPT. OF COMM. BIBLIOGRAPHIC DATA

SHEET

1. PUBLICATION OR RKPORT NO. NBSIR 77-1225

2. Gov't Accession

No.

3. Recipient's Accession No.

4. TITLE AND SUBTITLE

TEST AND EVALUATION OF THE SMOKE CONTROL CAPABILITIES OF

THE SAN DIEGO VETERANS ADMINISTRATION HOSPITAL

5. Publication Date April 1977

6 . Performing Organization Code

7. AUTHOR(S)

Francis C. W. Fung and Richard H. Zile

8 . Performing Organ. Report No.

9. PERFORMING ORGANIZATION NAME AND ADDRESS

NATIONAL BUREAU OF STANDARDS

DEPARTMENT OF COMMERCE

WASHINGTON. D.C. 20234

10. Project/Task/Work Unit No. 4928678

11. Contract/Grant No.

12. Sponsoring Organization Name and Complete Address (Street, City, State, ZIP)

Prepared for:

Office of Construction

Veterans Administration

Washington, D.C. 20420

13. Type of Report & Period Covered

Final Report

14. Sponsoring Agency Code

15. SUPPLEMENTARY NOTES

16. ABSTRACT (A 200-word or less (actual summary of most significant information. If document includes a significant

bibliography or literature survey, mention it here.)

A study was made by the National Bureau of Standards to evaluate the smoke

control capabilities of the San Diego Veterans Administration Hospital. A unique

feature of the hospital is the presence of independent air-handling units for each

floor and each wing. This feature allows the air—handling units to be manipulated

for smoke control following the systematic pressurization concept. Systematic

pressurization is a means of smoke control whereby a building is divided into

either vertical or horizontal compartmented zones such that the air-handling systems

are designed to exhaust the immediate fire zone and pressurize the adjacent surrounding zones upon detection of smoke. An experimental technique of smoke simulation

and smoke movement measurement was used for the study. The effectiveness of the

systematic pressurization smoke control concept is demonstrated by the simulated

smoke concentration profiles and pressure measurements.

An extensive series of experiments designed to evaluate the above smoke control

concepts were performed by the NBS in cooperation with the VA. Two types of experiments were performed with the building air-handling system operating in normal and

various smoke control modes. First, simulated smoke infiltration measurements were

obtained by using the sulfur-hexafluoride smoke simulation technique. Second,

17. KEY WORDS (six to twelve entries; alphabetical order; capitalize only the first letter of the first key word unless a proper name; separated by semicolons) Air-handling units; building pressure profile; computer

simulation; elevator shaft pressure profiles; parametric analysis; simulated smoke

concentration; smoke control; smoke movement; smoke simulation; systematic pressurization.

18. AVAILABILITY P? Unlimited 19. SECURITY CLASS 21. NO. OF PAGES

(THIS REPORT)

|

1 For Official Distribution. Do Not Release to NTIS

UNCLASSIFIED

|

1 Order From Sup. of Doc., U.S. Government Printing Office Washington, D.C. 20402. SD Cat. No. C13

20. SECURITY CLASS

(THIS PAGE)

22. Price

Order From National Technical Information Service (NTIS)

Springfield, Virginia 22151 UNCLASSIFIED

USCOMM-DC 29042-P74
ABSTRACT, continued

pressure measurements were obtained across elevator doors, and doors leading

from the building central core to each wing. Both SFg concentrations and

pressure measurements are key indicators of smoke movement in this evaluation.

Six basic air-handling test configurations were established and pressure

difference data was collected at fifteen locations on each floor measured.

At least two floors and more generally three floors were measured for each

mode. Each of the six configurations tested are summarized in table 7, and

the measured data are summarized in table 8. A total of six smoke simulation

experiments were conducted. The results and test conditions for each test are tabulated in tables 1 to 6 inclusively. It is concluded that airhandling systems in the San Diego VA Hospital can be effective in controlling

smoke movement if the proper vertical and horizontal systematic pressurization

concept as described in this report is applied. This is illustrated in

figures 7, 8, 11, and 12.

A computer smoke movement simulation analysis is also presented.

Computer calculations compared favorably with field data. Parametric

analysis was also performed on smoke control modes for varying environmental

and leakage conditions to further study the smoke control uses of the airhandling system and to demonstrate the capability of the computer simulation

program.

643 4




VVFRT BOOKBINDING

U’OOVETOWN PA JUNE 80