NBSIR 82-2634

Workshop on Combustion Product

Toxicity Summary of Presentations,

September 10, 1982

U S. DEPARTMENT OF COMMERCE

National Bureau of Standards

National Engineering Laboratory

Center for Fire Research

Washington, DC 20234

November 1982

Issued January 1983

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NBSIR 82-2634

WORKSHOP ON COMBUSTION PRODUCT

TOXICITY SUMMARY OF PRESENTATIONS,

SEPTEMBER 10, 1982

J. E. Snell, B. C. Levin, A. J. Fowell

U.S. DEPARTMENT OF COMMERCE

National Bureau of Standards

National Engineering Laboratory

Center for Fire Research

Washington, DC 20234

November 1982

Issued January 1983

U.S. DEPARTMENT OF COMMERCE, Malcolm Baidrige, Secretary

NATIONAL BUREAU OF STANDARDS, Ernest Ambler, Director
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Workshop on Combustion Product Toxicity

Summary of Presentations

September 10, 1982

J. E. Snell, B. C. Levin, A. J. Powell

FOREWORD

This publication is a summary of presentations given September 10,

1982, at a Workshop on Combustion Product Toxicity.

Publicity on fire deaths caused by smoke and toxic gases has given

impetus to a number of state legislatures to consider requiring material

toxicity provisions in building codes and other regulations. The National

Bureau of Standards recently published a technical report describing the

development of a test method for the assessment of the acute inhalation

toxicity of combustion products. This test method is intended primarily

for research and; f>r preliminary screening purposes by product researchers

and material manufacturers in developing and evaluating materials. The

test method is not intended to be used by itself in evaluating the suitability of a material for specific application since additional factors

must be considered.

Nonetheless, a number of fire, building code, and other regulatory

officials, as well as industry and association members, who have responsibilities relating to fire hazard assessment may benefit from learning more

about the test method, the background to its development, and limitations

on its appropriate use, and the relevance of this work to code, regulatory,

or material selection decisions or provisions.

Therefore, the National Bureau of Standards sponsored a half-day

workshop on combustion product toxicity, 9:00 a.m. - 12:00 noon, Friday,

September 10, 1982, at NBS in Gaithersburg, Maryland. The purpose of this

workshop was to brief fire code and building officials and others on the NBS

test method for assessing acute inhalation toxicity of combustion products

and to provide an opportunity for discussion of its appropriate use.

The agenda of the workshop is presented on page v. The presentations

are published here in the order they appear on the agenda.

iii
TABLE OF CONTENTS

Page

FOREWORD ili

AGENDA V

PRESENTATIONS

:

"Fire Hazard Assessment and Combustion Product Toxicity—An 1

Overview of the Context", Jack E. Snell

"NBS Protocol/Test Method for Assessment of the Acute Inhalation 13

Toxicity of Combustion Products", Barbara C. Levin

"Hazard Assessment—Review of Research in Progress and Planned" , 35

Andrew J. Fowell

APPENDIX - ATTENDANCE LIST 57

iv
WORKSHOP ON COMBUSTION PRODUCT TOXICITY

National Bureau of Standards

Green Auditorium

September 10, 1982

AGENDA

9:00 Welcome to NBS

9:10 Fire, Hazard Assessment & Combustion Product

Toxicity — An Overview of the Context

9:30 NBS Protocol/Test Method for Assessment of the

Acute Inhalation Toxicity of Combustion Products

10:10 Coffee Break

10:30 Hazard Assessment — Review of Research in

Progress and Planned

11:15 Question & Answer Session

12:00 Adjourn

Samuel Kramer

Deputy Director-Programs

National Engineering Lab

Jack E. Snell, Director

CFR

Barbara C. Levin, Head

Fire Toxicology, CFR

Andrew J. Fowell, Chief

Fire Safety Technology

Division, CFR

Jack E. Snell - Moderator

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Fire Hazard Assessment and Combustion Product

Toxicity—An Overview of the Context

Jack E. Snell

Good morning ladies and gentlemen. It's a pleasure for me to have the

opportunity to discuss this important topic with you. I'm advised I should

say at the very outset that our presentations are being video taped and the

questions and answers recorded so that we can make this information available

to others.

I've labored a great deal over how to begin this morning's program and

have concluded it would be most fitting to begin with the "answer" or the

"bottom line" as we see it and then successively through the balance of the

program fill in and elaborate in detail. The purpose of this workshop is

to provide interested parties in the fire community in general and particularly building and regulatory code officials a progress report on the Center

for Fire Research's work in combustion product toxicity. Specifically, we

wish to clear the air of any question or misunderstanding concerning NBSIR

82-2532 entitled, "Further Development of a Test Method for the Assessment

of the Acute Inhalation Toxicity of Combustion Products," a copy of which you

all now have.

And now here it comes, this is what we see as the bottom line. The

test method described in this report is primarily intended for research and

preliminary screening purposes for use by product researchers and material

manufacturers in developing and evaluating materials. It is not suitable

for use by itself for evaluating the fire safety of materials in use since

a number of additional factors must be considered in a specific situation.

Note the words "further development" in the title of this report. This

simply denotes the fact that this is not the first and certainly is not the

last report or word from us on this topic. Further development and evaluation of this test method and, in our view, all others currently available

is necessary to determine their suitability or utility for regulatory

purposes presuming the intent there of course, is fire-safe material/product

design, selection, or evaluation.

1
Please don’t be mislead by these remarks. We are concerned about

combustion product toxicity. However, we are much more intent upon

broadening our understanding of all the principal determinants of the

real threats or hazards posed by fire and the development of practicable

tools for yoi4T use in dealing with them. It’s our view that it will be

mutually beneficial to share with those of you in the regulatory community

as well as those in industry, our thinking on the technical issues that

remain to be resolved regarding combustion product toxicity in the broader

context of fire hazard assessment, and our current and planned research on these topics. Thus, even though we make no claim of offering a complete or easy solution to your current problems, we do believe this information will

be of practical use to you, now.

Therefore, it is our hope that each of you will leave this meeting with

a number of things. First, a clear understanding of what the test method is,

what it does and does not address, our views on its appropriate use, and

a copy of NBSIR 82-2532. Further, we hope you’ll have a clear understanding

of our plans for future research in this area. Also, we hope to answer your

questions. If we don’t answer them this morning, we’ll be sure to get the answers to you. Finally, we have asked each of you to fill out a registration card. It’s our intent to send each of you a brief summary of the

presentations of this morning for your further reference and also a list

of all the folks here with their affiliation for your use and reference in

getting the further information you may need to address the question of

hazard assessment in a specific design problem or context.

For our part we hope to gain from this meeting a clear perception of

the technical and measurement needs and concerns that you have so that to

the extent possible within our resource limitations our efforts are responsive to them.

Center for Fire Research Role in Combustion Toxicity Research

The National Bureau of Standards has been involved in fire research

from its very beginning. The Fire Prevention and Control Act of 1974

clearly dictated that the focus of the Center for Fire Research should be

2
on developing greater understanding of fire phenomena, and providing the

scientific and technical basis for development of sharper tools for resolving

the serious problem of fire in this country. From that time we have been

involved in combustion toxicity related work. This continued through the

efforts of the Product Research Committee in which we worked with a number

of groups in industry to broaden our understanding of materials' fire

properties in general and toxicity in particular. In September 1980 we published a preliminary toxicity test method that subsequently was used

in an interlaboratory evaluation and led to the development of the report

we'll be discussing this morning. This effort has involved a large number

of people. In fact, I'd venture to guess somewhere between 1/2 to 2/3 of

those here this morning have been involved one way or another in the

work we are talking about.

The topic of toxicity of combustion products from fires has been

a matter of a great deal of publicity recently and indeed a matter of

genuine concern within the fire community for quite sometime. For example,

the National Fire Protection Association, and the National Institute of

Building Sciences have recently held extensive meetings on this topic and

have commissioned special task forces to review the facts and generate

action recommendations for the fire community at large. In recent months a number of states have conducted hearings concerning the possible need for

regulatory measures to address toxicity concerns. These include New York,

New Mexico, and California. Also, CPSC and other federal agencies have

expressed similar concerns regarding certain products and furnishings.

Our Intent this morning is not to attempt to replicate these efforts or to

offer you a simple solution to the whole toxicity problem, but rather to

provide a perspective on our scientific and technical efforts that may be

useful to you in developing a lasting solution to this particular problem.

Fire Hazard Assessment

Now, let me say a few words about the context in which we see the

toxicity issue. Firstly, and most importantly, fire safety usually involves

tradeoffs (slide 1*). It's not a matter of safety at any cost. If that were

^Slides follow each presentation.

3
the case, we*d all be wearing glass clothing and living in stone shelters

as John Lyons is fond of saying. Rather, it's a matter of trade-offs between

funation^ safety and cost. These trade-offs are made typically in the marketplace and in the governmental or regulatory contexts. For example, one of the

model building codes defines an unsafe building as one which is a) structurally

unsafe, b) has inadequate egress, c) presents a fire hazard, or d) is otherwise dangerous to human life. Our concern this morning is with fire hazard.

Therefore, let's review our understanding of what we mean by this. The threat

or hazard of fire to human life evolves over time through a sequence of events.

I've listed on slide 2 a series of stages in the development of a fire and

shown graphically at the bottom of this figure on the horizontal axis time and

vertically some measure of fire intensity. The graph represents the process

of evolution of a fire and the occurrence of various phases. It all begins,

of course, with a pre-existing unsafe condition or practice, followed by the

subsequent steps of fire growth and extinction. Alternatively, at some point an intervention strategy may be employed, e.g., extinguishment in which case,

hopefully, the fire is knocked down before its intensity exceeds acceptable

limits.

My point in going through this, perhaps simple-minded illustration, is

simply this, our business is to provide the technical basis for interventions

that work in reducing fire loss. It's our conviction that an orchestrated

set of intervention strategies is essential. I've argued that it is socially

unacceptable to create an environment in which no unsafe condition or practice exists. It would be nice, but it's unrealistic. By the same token

it's unreasonable to expect that one single fire protection system or strategy is sufficient to deal with all possible fire threats and that it

makes no difference what we put into a facility or what materials we use in

its construction, furnishings, or finishings.

Now, let's take a closer look at what constitutes the threat of

fire to human life. Slide 3. First of all we have the fire itself, the

heat and flames, and the direct effect of them on building occupants.

Secondly, we have the combustion products, generally smoke, and thirdly we

have the overall event of the fire. Now we could think of each of these

in terms of the threat that they pose to individuals who might be in the

4
room of origin of the fire or elsewhere in the building in which fire might

occur. We can think specifically what senses, physiologically are insulted

by that aspect of the fire threat and develop means to characterize when and

at what point and to what extent those senses are threatened. It is important

for us to understand clearly the limits of tenability for each of those

threats. Some of the main ones include; the effect of heat on our sense of

feel 5 the irritant, toxic and visual effects of smoke; and the psychological/

physiological effects of the overall fire event in terms of stress on human

occupants.

Also, we can consider the properties of materials or products involved

in fire that give rise to these particular threats. For example, the pertinent

parameters relating to heat and flames are fairly well understood. We have

widely used test methods for flammability, ignitability , and combustibility,

and we are working on measures of flame spread, and rate of heat release.

These are measures we can use to understand the contribution of materials or

products to the threat of fire to human life, and they can be used in the

process of developing appropriate and effective intervention strategies. In

the same way, we would like to understand the irritant threat of smoke. We

know very little about that and are not all sure how to measure it. Those

who have been repeatedly in direct contact with fire argue convincingly about

its signficance and importance in disorienting or otherwise threatening

occupants in terms of their ability to escape.

The focus of our attention this morning of course is on inhalation

toxicity. Not only are the lethal aspects of smoke important, but also

the intoxicating or incapacitating effects of smoke which result in

occupants being subjected to further assault from other fire threats.

Similarly, the effect of smoke on visual obscuration interferes with

occupants’ ability to escape. We have reasonable measures of optical

density, and of smoke generation properties of materials, and these are

now widely used and cited in codes. Finally, we have no measures of

material or product properties that have been related to the overall

psychological stress of a fire, yet we know it’s important.

5
Ideally, of course, we would like to have means to measure the fire

properties of materials or systems that give rise to all of these threats.

We would like to be able to predict the evolution of fire hazards in time

and space, and use that understanding to test the effectiveness of various

interventions

.

Consider how, ideally, we might do this. I think we are all familiar

with the personal computer, video games, and interactive graphics. So, let

your imagination wander for just a moment and think about this problem in

that context (slide 4). Ideally, we would like to be able to provide as input to the computer the design, contents, occupancy and use of a building

including the major materials, furnishings and finishings, and the specific

activity patterns and so on that are likely to take place in it. Secondly,

we would like to be able to simulate a series of likely fire scenarios

including ignition, what materials are involved and in what sequence, the

responses of occupants and fire protection systems, etc., to the developing

hazard. Thirdly, we would like to have a means to evaluate quantitatively

the probable consequences of that simulation in terms of risk of life loss

and injury, in terms of property loss, and in terms of cost, etc. Think

about it. That would really be nice. That would provide us means to analyze

actual fire data and probable fire scenarios; to test designs, materials, and

furnishings, against those likely threats; and to test the performanceeffectiveness of various fire protection measures or systems in dealing with

those threats. This capability is now within our reach.

In fact, this is the principal focus of the program of the Center for

Fire Research. Dr. Fowell’s presentation will deal in some depth with where

we are now in terms of our ability to do just this. Before that, of course,

we want to describe for you in detail the toxicity test method. In closing,

let me just briefly recount in this broader context of fire hazard assessment

that fire safe material selection and use (slide 5) is situation specific,

it depends in a very significant way on the design of the material in

question, its form, contents, structure, on other materials present and their

properties, on fire protection systems and many other factors.

6
Now, I'd like to introduce Dr. Barbara Levin who heads our Fire

Toxicology Group. Barbara spent the last four years at NBS working on development of this test method, prior to that time she did postdoctoral

work at the National Institute of Health in biochemistry and microbiology.

She will be followed by Dr. Andrew Fowell. Andy is Chief of the Fire

Safety Technology Division of CFR. Andy is a mechanical engineer with a background in fluid mechanics and heat transfer research. He has 16 years

of private sector research and product development experience.

7
FIRE

SAFETY

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NBS Protocol/Test Method for Assessment of the Acute

Inhalation Toxicity of Combustion Products

Barbara C. Levin

Today I plan to describe the toxicity test method that we have

developed here at the National Bureau of Standards and to discuss its use

and its limitations. Most of what I plan to discuss is in the NBS report

entitled "Further Development of a Test Method for the Assessment of the

Acute Inhalation Toxicity of Combustion Products" (NBSIR 82-2532) which

you received at registration. I will certainly not be able to provide

all the information that is in the report, but, hopefully, this presentation

will introduce you to the report and will answer any of your current questions.

The first slide shows the objective and use of the NBS toxicity test

method. The objective is to assess the acute Inhalation toxicity of

combustion products under specified laboratory conditions. Its intended

use is for research and preliminary screening purposes by product researchers

and material manufacturers.

In slide 2, I will present some definitions to familiarize everyone

with the terminology used both in the report and this presentation. "Acute

toxicity" is defined as the harmful effects of a single short exposure to

combustion products generated by the thermal degradation of materials.

"Toxic hazard", on the other hand, is defined as the material and environmental conditions which Increase the probability that a toxic atmosphere

will occur and an injury will result. I’d like to emphasize that the test

method only addresses acute toxicity. It does not address the problem of

total toxic hazard. In this test method we also discuss "mass loading"

which is the amount of material placed in the furnace and thermally

degraded during the test itself. Another term is "auto-ignition temperature".

This is defined as the lowest furnace temperature which causes a material

sample, which is introduced into the cup furnace, to spontaneously ignite

within 30 minutes. For each material, the toxicity test is performed at

two different temperatures, a flaming temperature-25 °C above the autoignition temperature and a non-flaming temperature-25°C below the autoignition temperature.

13
Slide 3: Another term which needs definition is "concentration” which

is used in the test report in two slightly different contexts. In one case,

the concentration of a specific gas that is evolved into the exposure chamber

can be measured with laboratory instruments in parts per million (ppm) , for

example, carbon monoxide. On the other hand, it is very difficult to measure

the concentration in ppm of a mixture of unknown combustion products generated

when a material sample is decomposed. Therefore, the concentration of mixed

combustion products is defined as the mass loading of the material that is

placed into the cup furnace divided by the exposure chamber volume. This

concentration is expressed in milligrams per liter (mg/iO. "Concentrationresponse" is a graphic representation of the concentrations (ppm or mg/Jl)

required to produce a specified response in a percentage of animals. In

this test method, the biological response or endpoint which is measured is

animal death within the 30 minute exposure and/or within a 14 day postexposure observation period. From such a concentration-response cuirve (an

example will be shown later) an value can be estimated. An "LC^q" is

defined as the concentration which is necessary to produce death in 50% of

the test animals exposed for 30 minutes and observed for 14 days. The

values presented in the toxicity test method report were statistically

calculated by the method of Litchfield and Wllcoxon (J. Pharmacol, and Expt.

Therapeut. 9^:99-113, 1949).

Slide 4 shows a picture of the NBS exposure chamber. The test method

involves three components: a combustion system, a chemical analytical

system, and an animal exposure system. The combustion system is located

below the left side of the exposure chamber and consists of a cup furnace

(slide 5) in which the test material is decomposed at a preset temperature,

25°C above or below the predetermined auto-ignition temperature. The com- bustion products are generated directly in the exposure chamber. Some of

the smoke is pumped from the exposure chamber and analyzed continuously for

carbon monoxide, carbon dioxide, and oxygen during the 30 minute exposure.

All smoke removed for chemical analysis is returned to the exposure chamber,

i.e., the system is kept static.

This test is designed to assess the acute toxicity of combustion

products. In order not to confound the results with the physiological

effects of heat stress or oxygen deprivation on the animals, the test

14
method specifies that the average temperature at the nose level of the

animals during the exposure should not exceed 40°C. Temperatures at the

nose position of the animals as well as in the cup furnace are monitored

continuously during the exposure. Also the test method specifies that the

average oxygen levels throughout this exposure should not fall below 16%.

The exposure chamber is a 200 liter rectangular box and the animals,

six rats per experiment, are exposed in a head-only mode, l.e., only the

heads of the animals are exposed to the combustion products. The exposure

lasts for 30 minutes after which the animals are kept for a 14 day postexposure observation period. Blood is sampled from two of the six animals

and analyzed for carboxyhemoglobin. Carboxyhemoglobin is the molecule that

is formed within the blood when animals inhale carbon monoxide. As the

carboxyhemoglobin levels increase, the oxygen that is usually bound to the

hemoglobin is now displaced. In other words, when the blood becomes highly

saturated with carbon monoxide, the carboxyhemoglobin levels increase, the

oxyhemoglobin levels decrease, and the animals become starved for oxygen.

This test method also Includes an optional 10 minute exposure to a mass

loading of 30 milligrams per liter. The 10 minute exposure is intended

primarily to allow product researchers and material manufacturers to distinguish those materials which rapidly produce lethal concentrations of toxicants.

The response of the animal to the toxic insult absorbed during the test may

occur during the 14 day post-exposure period.

Slide 5 is a picture of the cup furnace consisting of a removable quartz

beaker surrounded by a heating element which is encased in insulation. A

thermocouple is placed in a well within the quartz beaker to monitor the

temperature throughout the exposure.

Most of the limitations of this test method concern the combustion

system (slide 6). One of the limitations is the quartz beaker size which

limits the quantity of material, especially low density materials, that can be accommodated by this combustion system. NBS did experiment with a larger

size cup furnace which was an improvement, but it still does not permit

large quantities to be tested. In addition, the cup furnace does not allow

15
for the continuous measurement of material mass loss throughout the experiments. In our present system we weigh the quartz beaker plus the material

before and after the exposure to determine how much material was decomposed

during the 30 minute exposure. Also, the effect of sample orientation is

not addressed by this test method. A material is literally dropped into the

cup furnace and falls whichever way it falls. Composite materials referred

to as "assemblages of nonuniform structure" in the test method report have

not been evaluated by this combustion system. And finally, there are two

degradation modes, flaming and nonflaming; we do not look at all possible

fire conditions.

As mentioned earlier, materials are examined above and below their

auto-ignition temperature. It would make the test extremely costly if every

material had to be tested at every temperature. The results of NBS and the

laboratories that participated in the interlaboratory evaluation of the test

method and data in the literature all show that the most toxic conditions

are generated at temperatures close to each material's auto-ignition

temperature. As the temperature rises and approaches the auto-ignition

temperature, more and more of the material is degraded and more toxic products

are produced. And, of course, in the flaming mode, the higher the temperature,

the more complete the combustion, the ultimate result of which is the production of only carbon dioxide and water. If materials are examined under their

most toxic conditions, then we avoid false negatives, i.e., the situation

where a material may produce even more toxic products under conditions that

have not been tested. The material modacrylic was decomposed at different

temperatures in both the flaming and nonflaming mode. The results (slide 7)

clearly show that as the temperature increases in the nonflaming mode, the

LC^q decreases, i.e., less material is needed to cause the animals to die.

The lower the value, the more toxic the situation is.

During the interlaboratory evaluation of the toxicity test method, seven laboratories examined a total of 12 materials including both synthetic

and natural materials. Not all the laboratories looked at all 12 materials.

The natural materials were Douglas fir, red oak and wool; the others were all

synthetic. The material abbreviations shown (in slide 8) are used throughout

16
the toxicity test method report. The test results that are provided here

and in the report pertain to the particular samples of these materials that

were used for this study and are not necessarily representative of the

generic class of materials that would fall under this particular name.

Slide 9 shows a typical concentration-response curve from which the

LC^q or the (the concentration necessary to incapacitate 50% of the

animals) can be estimated. The Y axis gives the percent response of the

animals and the X axis provides the concentration of the combustion products

as defined by the mass loading of material per unit chamber volume. Each

point (on this graph) is a single test consisting of six animals which were

exposed to one mass loading. From such data, we can now statistically

calculate the or the EC^^. During the development of the test method,

different biological endpoints were examined. The was calculated for

the 30 minute exposure itself as well as for the 30 minute exposure plus 14

day post-exposure observation period. In addition, the EC^q for 30 minutes

and the times-to-incapacitation were also determined.

Slide 10 shows NBS results for flaming combustion. The EC^^, the

concentration that caused 50% of the animals to become incapacitated in the

30 minute exposure; the EC^q, the concentration that caused death in 50% of

the rats in the 30 minutes and 14 days; and the the concentration that

caused lethality in 50% of the rats during the 30 minute exposure itself, are plotted against the mass loading divided by chamber volume for all 12

materials. In classical toxicology, one material is considered significantly

more toxic than another material if the toxic concentrations differ by an order of magnitude. However, in this series of experiments, only one material

(PTFE) turned out to be orders of magnitude more toxic than the other materials

* tested. These data also show that regardless of the endpoint (EC^q or EC^q)

examined, the relative toxicities of the materials do not significantly change

except for PTFE. With this particular material, all deaths occurred postexposure. No incapacitation or death was observed during the thirty minute

exposure. A hundred fold increase in the mass loading of this material still

Experiments carried out in another laboratory subsequent to the publication

of this report indicate that the conditions of thermal decomposition used

in the NBS test—i.e., the absense of flame from other combustibles—may not

be appropriate to the toxicity testing of PTFE (the only poljnneric material

which does not contain hydrogen). Testing in a hydrocarbon flame indicated

1-hp T.r. Kp ciicrVit-iAT loss than but of the same order of magnitude as for

*

17
did not produce any Incapacitation or death within the 30 minute exposure.

Our conclusion from this information is that the biological endpoint that

provides the most information as to the toxicity of a material is the

for 30 minutes and 14 days which includes the post-exposure results.

The toxicity test method also includes an optional 10 minute test which

is primarily designed to enable product researchers and material manufacturers

to distinguish those materials that rapidly produce effective concentrations

of toxicants. Slide 11 shows the results of this test performed on two

materials - PVC and PVC-ZnFeCN under both flaming and non-flaming conditions.

These materials have the same chemical formulation except that the PVC-ZnFeCN

has in addition zinc ferrocyanide, a smoke suppressant. The 10 minute results

can be compared to the values for 30 minutes and 14 days. Using orders

of magnitude as the criterion to determine whether one material is significantly

more toxic than another material, these two materials can not be distinguished

by the results. However, when the animals were briefly exposed for 10

minutes to 30 mg/2, and observed for 14 days, the PVC-ZnFeCN killed 100% of

the animals in all cases in both the flaming mode and the nonflaming mode.

PVC, however, produced only one animal death in three experiments in the

flaming mode and no deaths in the non-flaming mode. Therefore, the 10 minute

test provides a means of distinguishing between materials which rapidly produce toxicants and those that do not.

As an example of the Importance of following the toxicity test method

closely, slide 12 shows some of the research performed at NBS to determine

the best time to take blood samples. The test method specifies that the

blood samples for carboxyhemoglobin measurements should be taken either at

the end of the exposure or within 5 minutes following the end of the exposure.

Slide 12 shows the percent of hemoglobin saturated either with oxygen or carbon

monoxide plotted against time. The time axis is divided into the time of the

exposure (30 min.) and a long post-exposure period during which blood samples

were taken. These animals were exposed to an average concentration of 4100

ppm of carbon monoxide for 30 minutes and no animals died. During the exposure,

there is a rapid increase in carboxyhemoglobin to a level of 84% and simultaneously, there is a rapid decrease in the oxyhemoglobin. Immediately upon

removal of these animals from the chamber, the carboxyhemoglobin levels start

to drop. The decrease in percent carboxyhemoglobin is so rapid that if blood

samples are taken long after the exposure is over, the levels observed will

not be related to that which the animals actually experienced during the

18
exposure Itself. Therefore, we do recommend arterial cannulation of the

animals. This procedure allows blood sampling without removing the animals

from the exposure conditions. However, if cannulations are not performed,

then rapid sampling is important for reliable results. The longer the delay,

the more significant the error.

Post-exposure death was not an Isolated phenomenon. The combustion

products of many materials produced both within-exposure deaths and postexposure deaths at the concentrations tested. A few materials produced only

within-exposure death 'and a few materials produced only post-exposure death.

Therefore, in the assessment of the toxicity of the combustion products of

materials, it is important to examine both within-exposure and post-exposure

deaths. The test method specifies that the animals be observed for 14 days,

a time period during which the various materials caused deaths (slide 14)

.

What about the reproducibility of this test method? As mentioned

earlier, an Interlaboratory evaluation was conducted. The LC^q results for

30 minutes and 14 days for Douglas fir as determined by seven laboratories

are shown in slide 15. NBS is listed here at NBSa and NBSb because NBS tested

both a 360 ml furnace and 950 ml furnace. Douglas fir is the appropriate

material to examine for reproducibility across laboratories as all of the

laboratories tested Douglas fir and only a few laboratories tested each of

the other materials. The Douglas fir results show good reproducibility

between laboratories under both non-flaming and flaming conditions. It is

important to note that this was an interlaboratory evaluation; it was not a round-robin in which each laboratory was told exactly what concentrations to

test and how to exactly replicate experimental conditions. There were variations both in how experiments were run and the methodology used. However,

slide 15 still shows good reproducibility between laboratories. Data for

other materials can be found in Table 17 of the test method report (NBSIR

82-2532) . NBS is planning to publish a report on the interlaboratory

evaluation of this other data soon.

In conclusion, this presentation has described very briefly the toxicity

test method that was developed here at the National Bureau of Standards and

discussed its use and its limitations. The Center for Fire Research is

planning future work to correct these limitations and Dr. Fowell will be

discussing our future research plan after the coffee break. Thank you.

19
NBS

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33

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34

In

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variations.
Hazard Assessment—Review of Research in

Progress and Planned

Andrew J. Powell

My purpose today is to describe the additional research planned at NBS

relating to the toxicity test method and to toxic hazard assessment. First,

I'll discuss some of the current limitations of the test method particularly

those on which we intend to concentrate our effort. Then, I'll describe

various approaches to hazard assessment, and give an example of the kind of

output that we expect from some of the more elaborate techniques. Finally,

I'll outline our plans for work in hazard assessment methodology.

(See slide 1). Several test methods for measuring combustion product

toxicity are now available. They can provide information for research and

product development but they should not be incorporated directly into building

codes and standards, for a number of reasons. There is very little available

information on toxicity of materials obtained using either the NBS or the

other test methods and the ways to use this information have not yet been

developed. Also, some technical issues need to be resolved including how to

deal with composite assemblies of materials and material orientation. At NBS

we are focusing on two areas: the further refinement of the test method to

address some of the current limitations; and the development of a framework

for combining toxicity information with the other information so that regulators

or decision makers can make better decisions on fire safety. This other

information—which includes the material's own fire properties, use data, and

statistics on fires—may be considered "application information". The com- bination of "material performance" data with "application information" comprise

toxic hazard assessment. This is shown in dashed lines because to date we lack

procedures for conducting such an assessment.

What are the current limitations of the toxicity test method? (See

slide 2). Barbara Levin mentioned these. The time to reach untenable

conditions is a key factor in addressing hazard. So, an indication of the

rates of generation of combustion products is important. Therefore, some continuous measure of mass loss of the material would be a good indicator.

Few materials are ever used on their own; they are usually used in

35
combination with other materials or formed into assemblages of materials.

The current test method has not really addressed composite materials. To

test these materials a different combustion system will probably be needed,

and it is likely to be some form of radiant system. The size of the present

cup furnace is a limiting factor for low density materials. In burning

materials, oxygen is a critical factor in determining the products of com- bustion, particularly carbon monoxide. Therefore, some measure or control

of the oxygen in the combustion system should be included. The exposure

conditions, the ventilation conditions and the material orientation all are factors that contribute the combustion products and therefore our combustion systems must take this into account.

We in the U.S. are not the only people working on combustion toxicity.

Efforts are underway in Japan, Germany, Canada, England, France, Sweden, and

many other countries. The Japanese are focusing on the correlation between

small scale and large scale tests, which bears on the subject of verification.

The Japanese also are attempting to simulate real fire conditions. The

Canadians concentrate more on analytical techniques rather than exposing

animals. Although the English researchers have used primates in their tests,

they concentrate mostly in the analytical area. We in the U.S. have set up

collaborations with both Japan and Canada to exchange information and look

at the correlation between our various test methods and the results of using

the various techniques.

What are we planning to do about the limitations of the test method

mentioned? (See slide 3). The first effort will be to better control com- bustion by redesigning combustion systems. We have done some initial work

on radiant heating systems. Our work in full-scale testing and modeling of

fires will give us a lead on the design requirements of that combustion

system. At the same time as refining the combustion system, we may modify

the animal exposure system if necessary to control the temperature at the

noses of the animals, and the oxygen level to make sure that the animals

aren’t too affected by high gas temperatures or oxygen depletion.

Once modifications have been made to the test equipment we will

correlate any new measurements with the data we have from the old system.

36
Following the modifications to the equipment, we plan to examine the composite

material and material orientation questions. Another problem we see with

toxicity testing is cost. It would be very nice to explore every parameter

in every direction. This is impractical. Some time can well be spent

selecting appropriate standard test conditions.

As we have said a number of times today, when considering the suitability of a material for a particular use the results of small scale toxicity

tests should be considered along with information on its other fire properties.

In fact, in the test method itself we list a number of these properties in the

"Significance and Use" section of the report, (section 2.2.2).

Combining this fire property information with application information

leads to hazard assessment. Various approaches that either have or can be

used for hazard assessment are listed on slide 4. I'm going to concentrate

on the last two items. They are the more quantitative approaches. But

first, let's look at chemical analysis techniques. Since they don't rely on animal testing, some unsuspected or unknown toxicants can be missed. The

French code requires* the use of a chemical analysis technique in the regulation of building materials in public buildings. They consider two gases,

hydrogen chloride and hydrogen cyanide. A limit is placed on the maximum

concentration of these gases that could possibly be generated by the chlorine

and nitrogen in the furnishings of the room and the wall covering materials.

There are various weighting factors Incorporated into the calculations when

floors and walls are considered. The second approach on the list, subjective

assessment, is really the approach that is being used today. It's a way of

comparing the various fire properties of different materials with those of

some standard material or with some other familiar material.

Of the the two more quantitative approaches to hazard assessment the

last one, mathematical modeling, is the more sophisticated or elaborate.

It combines mathematical models of fire growth and fire spread with the

capabilities of computers to predict the time to reach untenable conditions

*Since this presentation, it has come to our attention that this analysis

technique is not in regular use in France.

37
within various parts of the building under various fire scenarios. But

first, let's look at each of the two quantitative approaches.

The information that we get from the test method, the is the mass loaded in thecombustion system divided by the volume of the chamber which is

necessary to cause death in fifty percent of the animals as a result of a 30

minute exposure (slide 5).

If we multiply the by 30 minutes, it gives us some idea of the

lethal dose D* for the animals. Now consider a compartment containing a burning material. The rate of mass loss of that material is m^. The

burning material generates flow into and out of the room through any open

doorway or window. The voliame flow out of the room v can be calculated

o from the heat generated by the burning material and the temperature in the room. So we have a concentration of toxicants flowing out of the room, the mass generated divided by the volume flow rate. Multiply that by the time

under consideration and we have a dose. So now we have a very crude, very

simple way, assuming the material is burning at a steady state, to calculate

the time to reach a lethal dose. Now I'd be the first to recognize that for

many toxicants the lethal dose itself is dependent on concentration. In fact,

in the test method, we recognize this by doing a 10 minute test. But, for

the purposes of this crude calculation we'll make that assumption. We can elaborate on this technique by adding to the calculation the time for a material to get Involved in the fire. The techniques to do this are available

and they give us a much better indication of time to reach toxic conditions.

A more elaborate or ideal method of assessing fire hazard is to combine

the latest models of both fire growth and fire spread with the capabilities

of computers to predict the changing conditions in various parts of a building.

(See slide 6). Here I show just two examples of fire growth models. One

developed at Harvard for single compartments and another one developed by

Professor Tanaka in Japan, for multi-room or multi-compartment spread of

smoke throughout a building. There are many models and many submodels available. In the first one, the fire growth within a single compartment, the

usual approach is a zone model where the compartment is divided into a number

of zones, such as the upper smoke layer, the lower cooler layer, and the

turbulent plume above the fire. (See slide 7). Some of the factors that are considered in developing these various models include the air flow

38
Into the room, the mixing of the products of combustion into that inflow air,

the escape of the products of combustion, heat transfer to the ceiling and

walls, and radiation from the flame and from the upper zone to the floor and

to other materials in the room. This particular model is undergoing various

stages of modification and parameters are constantly being added or modified.

Thus, the model is becoming much more sophisticated.

This next slide (see slide 8) is a pictorial representation of the Tanaka

model of smoke filling a building. Starting in the upper left corner of the

slide, we see a fire on the second level generating smoke which spreads from

the room of origin into neighboring compartments and to the upper floors. As

we examine the figures down the left hand side and then down the right hand

side of the slide we see a progressive filling of the building with smoke. So,

through a combination of models like these that we can generate the overall fire

hazard or the fire safety picture for a particular building.

In the report on the test method, we list a number of factors that should

be combined in assessing overall fire hazard. Some of these are listed on slide 9. These same factors really form the input to these mathematical models.

It isn’t a complete list but it does show you some of the pieces of Information

that need to be incorporated into the models to give us a good understanding of

the fire growth. The output that is of interest to us at the present time is

the time to reach tenability limits. These tenability limits have to do with

toxicity, temperature, and visibility. We are examining the literature to

determine what values to use for these limits.

An important purpose of modeling is to gain a better understanding of the

fire growth process and to reduce the number of repetitive large scale tests

that must be done. As a result many subroutines are continually being added

to the modeling framework to account for the various components of the fire

process. (See slide 10). Modeling capabilities are limited at this time,

primarily by lack of data on both individual materials and composite materials.

Another limitation is lack of information on the combustion products in underventilated conditions that are different from those of the test methods. This

is one of the criticisms that a standard test method usually encounters. One

of the problems with the models that are available today is they’re not necessarily compatible with each other and so we will be working to improve

39
model compatibility. As I said, mathematical modeling is continually being

improved by the incorporation of other factors. Factors currently being

addressed are forced ventilation and wall fires. In most of the models that

exist today, the flows within and between the various compartments associated

with the fire, are assessed on the basis of the buoyant effects of the fire

itself, whereas, in big buildings the heating, air conditioning, and smoke

control systems are a major factor. Not only do we need combined models, or models that are compatible with each other, we also need efficient algorithms

so that we can process each model conveniently. Another problem that we have

encountered is that many of today’s models can only be handled by the experts

who developed them. So, effort needs to be directed at simplifying and

refining the models.

Modeling gives a good overall picture of the fire growth process if you

know where the fire starts, but what is the probability that a fire will

start in a particular way, or particular location? We need more input on

fire scenario probabilities. Fire statistics that are available today can provide some of this information.

These limitations not withstanding current fire and smoke models can provide useful information. For example, we have run two of the models,

the two that I mentioned earlier, the Harvard Code and the Tanaka model, in

combination with each other for a very simple situation. (See slide 11)

.

The setup we used was a two room building, the room of origin, (a bedroom)

and the rest of the house. We considered only one combination fuel package,

a bed and two side tables, but with two different sets of materials. In each

case, the fire was assumed to start in the middle of the bed. In this hypothetical example, the kind of output we might expect is shown in slide 12.

Tenability limits for temperature and visibility were assumed as follows:

lower layer room temperature reaches 100° C; and the smoke layer reaches Im

from the floor. Two toxicity tenability limits were assumed a) for all the

products of combustion, 30 x mg/ii min; and b) for carbon monoxide,

4500 ppm min. For each of the fuel packages, designated A and B, we calculated the conditions which first made each room untenable. What this

particular example turned up was that tenable conditions persisted in both

the room of origin and the rest of the building with fuel package A. With

fuel package B, we did run into tenability limits in very short order.

40
visibility happened to be the first one. This occurred in both the room of

origin and the rest of the building. The smoke layer came to within one meter of the floor in 4 to 5 minutes. The second limit that was reached was

the lower layer temperature in the room of origin reached 100°C in 5 or 6

minutes. Lethal levels of toxicants were not reached in neither of these cases which involved relatively small fuel loadings.

What is our overall plan for hazard assessment in the Center for Fire

Research? (See slide 13). It includes research, test method development,

experimental studies, particularly in the area of extinguishment systems, an extension to our work in fire modeling and what is more Important to you in

the audience, the development of models that can be used by the people other

than those who develop them. The research effort will include studies such

as particulate generation, particulate coagulation, smoldering fires and the

combined effects of various toxicants. Work on the development and refinement of test methods will include the rate of generation of combustion

products, the rate of heat release, flame spread and refinements to combustion

toxicity testing. Not all fires continue unchecked. Fire control systems are effective. So we plan to study the response and effectiveness of extinguishment systems and the effectiveness and field testing of smoke control systems.

I have already mentioned that our fire growth modeling will be developed

further, particularly the single compartment model where we will address

wall fires, forced ventilation, incorporate extinction effects and the use of layered materials on the walls. The multi-room smoke model will be

extended to improve prediction of the lower layer temperatures in the various

parts of the building, and to handle mixing of the upper and lower layers,

scrubbing of combustion products as they flow around the building, and the

effectiveness of smoke control systems. That’s an ambitious package. It

will take quite a long time before all that is complete. However, we Intend

to develop usable interim models and information for fire hazard assessment.

(See slide 14). Some of the more useful techniques that will come out of

this program will be cost and loss models, and building egress models. In

addition to those tools we’ll be developing or gathering basic data such as various fire scenario probabilities, tenabillty limits, fire properties of

the Individual materials and assemblies of materials.

41
In summary, what I've covered today is the work we are planning on the test method Itself, some approaches to hazard assessment and an outline

of our program for developing useful tools for hazard assessment.

42
CONTEXT

OF

ADDITIONAL

RESEARCH

Slide 1

43
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continuous

mass

loss

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SELECT

MOST

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CONDITIONS
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46
RATE

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COMBUSTION

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GENERATION

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to

lethal

dose

At
HAZARD

•

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growth

model

(Harvard

-

ASSESSMENT

single

compartment)

METHODOLOGY

•

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spread

model

(Tanaka

-

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multi

compartment)

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48
Phenomerici

of

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LOW

SPEED

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FLOWS
•

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MIN.
FACTORS

ASSOCIATED

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ASSESSMENT

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input

data

LIMITATIONS -

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materials

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ASSUMED

FIRE

SITUATION

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OF

PROPOSED

OUTPUT

(hypothetical

example)

Slide 12

54
HAZARD

•

Research

and

test

method

ASSESSMENT

development

PLAN

•

Experimental

studies

-

fire

control

systems

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55
USER

MODELS

•

Cost/loss

models

AND

DATA

FOR

•

Building

egress

models

HAZARD

•

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scenario

probabilities

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56
APPENDIX

ATTENDANCE LIST

National Bureau of Standards

Workshop on Combustion Product Toxicity

September 10, 1982

Dr. H. (Pat) Adams, Jr.

Technical Director

Man-Made Fiber Producers Assoc.

1150 17th Street, NW.

Washington, D.C. 20036

(202) 296-6508

Mr. Charles W. Almand

Manager, Governmental Services

U.S. Gypsum

1050 17th Street, NW, Suite 1150

Washington, D.C. 20036

(202) 223-8266

Dr. Rosalind C. Anderson

Toxicologist

Arthur D. Little, Inc.

Acorn Park

Cambridge, MA 02140

(617) 864-5770

Mr. Bruce D. Anson

Engineer

Rohm & Haas Company

Independence Mall West

Philadelphia, PA 19107

(215) 592-3644

Mr. Bernard E. Auerbach

Manager, Standards Information

Allied Tube & Conduit Corporation

16100 South Lathrop Avenue

Harvey, IL 60426

(312) 339-1610

Mr. Irwin A. Benjamin

Vice President

Benjamin/ Clarke Associates, Inc.

10605 Concord Street

Kensington, MD 20895

(301) 949-1414

Mr. David W. Bensen

Program Manager

Federal Emergency Management Agency

500 C Street, SW.

Washington, D.C. 20472

(202) 287-3874

Mr. Jim Beyreis

Managing Engineer, Fire Protection

Underwriters Laboratories, Inc.

333 Pfingsten Road

Northbrook, IL 60062

(312) 272-8800 (x2301)

Dr. Merritt M. Birky

Director of Research

Foundation for Fire Safety

1700 North Moore Street, Suite 1508

Rosslyn, VA 22209

(703) 276-9222

Mr. Richard G. Bright

Fire Protection Engineer

Consultant

10303 Huron Court

Mt . Airy, MD 21771

(301) 831-9105

Mr. David J. Burkhart

Student-Fire Protection Engineering

University of Maryland

P.O. Box 223

College Park, MD 20740

(301) 434-2400

Mr. Robert W. Burns

Principal Engineer - Fire Protection

State of New Jersey, Bureau of

Construction Code Enforcement

363 West State Street

Trenton, NJ 08625

(609) 292-6254

Dr. Frederic B. Clarke

President

Benjamin/Clarke Associates, Inc.

10605 Concord Street

Kensington, MD 20895

(301) 949-1414

Mr. Eugene T. Cumberland

Codes Enforcement Officer

Codes Administration - Department of

Economic and Community Development

2525 Riva Road

Annapolis, MD 20714

(301) 269-2701

57
2

Mr. Alvin D. Delman

Manager, Testing Services

The Wool Bureau, Inc.

225 Crossways Park Drive

Woodbury, NY 11797

(516) 364-0890

Mr. John W. Fothergill, Jr.

President

Integrated Systems, Inc.

P.O. Box 128

Brunswick, MD 21716

(301) 834-7117/(703) 734-9057

Mr. Joseph G. DiPinto

Product Technology Manager

DuPont Company

11070 DuPont Building

Wilmington, DE 19898

(302) 774-7807

Ms. Jane N. Fowler

Administrative Assistant

Upholstered Furniture Action Council

918 16th Street, NW. , Suite 402

Washington, D.C. 20006

(202) 466-7362

Mr. John C. Drinkard

Building Code Supervisor

State of Virginia

205 North Fourth Street

Richmond, VA 23219

(804) 786-5031

Mr. William R. Freeman, Jr.

Government & Architectural Services

Koppers Company, Inc.

11724 Critton Circle

Woodbrldge, VA 22192

(703) 690-3550

Mr. Daniel Drozdowski

Assistant Vice President

U.S. Testing Company

1415 Park Avenue

Hoboken, NJ 07030

(201) 792-2400 (x346)

Mr. Kenneth R. Frese

District Fire Protection Engineer

Office of State Fire Marshal (Virginia)

319 Landmark Towers

101 South Whiting Street

Alexandria, VA 22304

(703) 751-1008

Mr. W. A. Dunlap

Codes & Standards Specialist

Dow Chemical Company

P.O. Box 515

Granville, OH 43023

(614) 587-4382

Prof. Irving Einhorn

Mr. Richard G. Gewaln

Chief Fire Protection Engineer

American Iron and Steel Institute

1000 16th Street, NW.

Washington, D.C. 20036

(202) 452-7194

Vice President

Center for Environmental and

Materials Research

1550 Asylum Avenue

West Hartford, CT 06117

(203) 233-6056

Mr. Robert W. Glowinski

Manager, Fire Technology

National Forest Products Association

1619 Massachusetts Avenue, NW.

Washington, D.C. 20036

(202) 797-5884

Mr. Wayne P. Ellis

Manager, Industry Standards

H. B. Fuller Company

P.O. Box 625

Spring House, PA 19438

(215) 628-2600

Mr. Tom Goonen

Senior Engineer

Schirmer Engineering Corporation

803 W. Broad Street

Falls Church, VA 22046

(703) 237-8211

Mr. Daniel J. Falngnaert

Technical Representative - Chemist

Stauffer Chemical Company

Grasslands Road

Elmsford, NY 10523

(914) 592-9010

/

58
3

Ms. Cheryl Grounds

Student (Fire Protection Engineering)

University of Maryland

6864 Riverdale Road, #101

Lanham, MD 20706

(301) 577-7851

Mr. Matthew T. Gustafson

Student (Fire Protection Engineering)

University of Maryland

43 Hatton Drive

Severna Park, MD 21146

(301) 647-4847

Mr. David M. Hammerman

Director

Codes Administration

2525 Riva Road

Annapolis, MD 21704

(301) 269-2701

Ms, Rea Harwood

Statistician

U.S. Consumer Product Safety

Commission

5401 Westbard Avenue

Washington, D.C. 20207

(301) 492-6470

Mr. Marvin Hassman, P.E.

Director, Materials & Equipment

Acceptance Division

Department of Buildings, City of

New York

120 Wall Street

New York, NY 10005

(212) 248-8817

Mr. Edward Heisnell

Associate Building Construction

Engineer

New York State Housing and Building

Codes Bureau

60th Floor, Two World Trade Center

New York, NY 10047

(212) 488-4912

Mr. Thomas M. Helscher

Manager, Regulatory Affairs

Monsanto Company

1101 17th Street, NW.

Washington, DC 20036

(202) 452-8880

Dr. Robert K. Hinderer

Senior Toxicologist

B. F. Goodrich Company

500 S. Main Street

Akron, OH 44318

(216) 374-4534

Mr. Richard N. Hopper

Director of Governmental Affairs

Carpet & Rug Institute

Suite 700, 1629 K Street, NW.

Washington, D.C. 20006

(202) 223-2578

Mr. A. Larry Iseminger, Jr.

Fire Protection Engineer

Maryland State Fire Marshal's Office

301 West Preston Street

Baltimore, MD 21201

(301) 383-2522

Ms. Deborah Kale

Statistician

U.S. Consumer Product Safety

Commission

EPHA, Room 642

Washington, D.C. 20207

(301) 492-6470

Mr. Richard G. Katz

Fire Data Analyst

Federal Emergency Management Agency

500 C Street, SW.

Washington, DC 20472

(202) 287-0766

Mr. David Kay

Fire Prevention Engineer

Naval Sea Systems Command

Code 55X32

Washington, D.C. 20362

(202) 692-1242

Mr. Richard P. Kuchnicki

Executive Director

Council of American Building Officials

5205 Leesburg Pike, #1201

Falls Church, VA 22041

(703) 931-4533

59
4

Mr. Ronald J. Kunego

Foamwall Product Manager

E. G. Smith Division - Cyclops Corp.

100 Walls Street

Pittsburgh, PA 15042

(412) 761-7474 (x234)

Mr. Thomas E. Lewis

Manager, Govt. Tech. & Mkt. Services

Armstrong World Industries, Inc.

1025 Connecticut Ave. , NW. , Suite 1007

Washington, D.C. 20036

(202) 296-2830

Mr. Larry Litchfield

Deputy Chief Engineer

State of Wisconsin DILHR

Safety & Buildings Division

201 E. Washington Avenue

Madison, WI 53707

(608) 266-0675

Mr. George E. Maloney

Senior Engineering Consultant

The Travelers Insurance Company

7617 Little River Turnpike

Annandale, VA 22003

(703) 750-4196

Mr. Francis A. McGarry

State Fire Administrator

N.Y.S. Office of Fire Prevention

162 Washington Avenue

Albany, NY 12231

(518) 473-3590

Mr. Lawrence A. McKenna, Jr.

Student (Fire Protection Engineering)

University of Maryland

11930 Beltsville Drive, #14

Beltsville, MD 20705

(301) 572-2471

Mr. Don Moore

Architect

HUD

451 7th Street, SW.

Washington, D.C. 20410

(202) 755-6590

Mr. G. R. Munger

President

Society of the Plastics Industry, Inc.

355 Lexington Avenue

New York, NY 10017

(212) 573-9440

Mr. John Munno

Student (Fire Protection Engineering)

University of Maryland

4606 Beechwood Road

College Park, MD 20740

(301) 454-2436

Ms. Margaret L. Nelly

Chief, Flammability & Textiles Branch

Engineering Sciences

Consumer Product Safety Commission

Room 735, WTB

Washington, D.C. 20207

(301) 492-6494

Dr. Rita Orzel

Chief , Toxicology Review Branch

Directorate for Health Sciences

Consumer Product Safety Commission

5401 Westbard Avenue

Bethesda, MD 20207

(301) 492-6994

Mr. Robert Robins

Chief Engineer

Hardwood Plywood Manufacturer’s Assoc.

P.O. Box 2789

Reston, VA 22090

(703) 435-2900

Mr . H . J . Roux

Coordinating Manager

Armstrong World Industries, Inc.

Lancaster, PA 17604

(717) 397-0611

Mr. Van M. Seabaugh

Toxicologist

Consumer Product Safety Commission

200 C street, SW.

Washington, D.C. 20204

(202) 245-1445

Dr. L. J. Sharman

Fire Programs Officer

Consumer Product Safety Commission

5401 Westbard Avenue

Bethesda, MD 20207

(301) 492-4554

60
5

Mr, Tony Shaw

Manager of Technical Information

Hoechst Fibers Industries

P.O. Box 5887

Spartanburg, SC 29304

(803) 579-5382

Mr. Joseph G. Werner

Vice President

National Electrical Manufacturers Assoc.

2101 L. Street, NW.

Washington, D.C. 20037

(202) 457-8444

Mr. Robert S. Strength

Product Safety & Acceptability Manager

Monsanto Plastics & Resins Company'

800 N. Lindbergh Blvd.

St. Louis, MO 63167

(314) 694-3211

Mr. Franklin E. Williams

Division Lab. Manager

Burlington Industries

Anderson Street

Glasgow, VA 24555

(703) 258-2811

Mr. Hugh Patrick Toner

Society of the Plastics Industry, Inc.

355 Lexington Avenue

New York, NY 10017

(212) 573-9422

Mr. H. F. Van Der Voort

Vice President, Industry Affairs

Carlon

23200 Chagrin Blvd.

Cleveland, OH 44122

(216) 831-4000

Mr. William Wald

General Manager, Marketing

Tech. Services

Burlington Industries

Valley Forge Corp. Center

King of Prussia, PA 19406

(215) 666-7770

Mr. Robert E. Warr

Consultant - Standards

General Electric

Fairfield, CT 06431

(203) 373-2288

Mrs. Susan Womble

Chemist

Consumer Product Safety Commission

5401 Westbard Avenue

Bethesda, MD 20207

(301) 492-6994

Mr. Raymond S. Zielinski

Code Enforcement Specialist

N.Y.S. Office of Fire Prevention & Control

162 Washington Avenue

Albany, NY 12231

(518) 474-6746

Mr. Rodney L. Wells

Research Specialist, Polymer

Technology

Allied Corporation

P.O. Box 31

Petersburg, VA 23804

(804) 520-3621

61
NBS-114A (REV, 2-80

U.S. DEPT. OF COMM.

BIBLIOGRAPHIC DATA

SHEET (See instructions)

PUBLICATION OR

REPORT NO.

NBSIR 82-2634

2. Performing Organ. Report NoJ 3. Publication Date

4. TITLE AND SUBTITLE

Workshop on Combustion Product Toxicity

Summary of Presentations, September 10, 1982

5. AUTHOR(S)

Jack E. Snell, Barbara C. Levin, Andrew J. Fowell

6. PERFORMING ORGANIZATION (If joint or other than NBS, see instructions) 7, Contract/Grant No. national bureau of standards - _

DEPARTMENT OF COMMERCE S WASHINGTON, D.C. 20234

9. SPONSORING ORGANIZATION NAME AND COMPLETE ADDRESS (Street. City. State. ZIP)

. Type of Report & Period Covered

10. SUPPLEMENTARY NOTES

I I Document describes a computer program; SF-185, FIPS Software Summary, is attached.

11. ABSTRACT (A 200-word or less factual summary of most significant information. If document includes a significant

bibliography or literature survey, mention it here)'j;iij^g publication is a summary of presentations

given September 10, 1982, at a Workshop on Combustion Product Toxicity. Publicity on fire deaths caused by smoke and toxic gases has given impetus to a number of state

legislatures to consider requiring material toxicity provisions in building codes and

other regulations. The National Bureau of Standards recently published a technical

report describing the development of a test method for the assessment of the acute

inhalation toxicity of combustion products. This test method is intended primarily for

research and for preliminary screening purposes by product researchers and material

manufacturers in developing and evaluating materials. The test method is not intended

to be used itself in evaluating the suitability of a material for specific application

since additional factors must be considered. Therefore, the National Bureau of

Standards sponsored a half-day workshop on combustion product toxicity, 9:00 a.m. - 12:00 noon, Friday, September 10, 1982, at NBS in Gaithersburg, Maryland. The purpose

of this meeting was to brief fire code and building officials and others on the NBS

test method for assessing acute inhalation toxicity of combustion products and to

provide an opportunity for discussion of its appropriate use.

12. KEY WORDS (Six to twelve entries; alphabetical order; capitalize only proper names; and separate key words by semicolon s) building codes; combustion products; fire growth modeling; hazard assessment;

inhalation; materials; test method; toxicity.

13. AVAILABILITY

l_Xj Unlimited

I I For Official Distribution. Do Not Release to NTIS

I I Order From Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402.

Order From National Technical Information Service (NTIS), Springfield, VA. 22161

14. NO. OF

PRINTED PAGES

65

15. Price

$9.00

USCOMM*DC 6043-P80