NBSIR 77-1381

Preliminary Report on

Evaluating Alternatives for

Reducing Upholstered

Furniture Fire Losses

Benjamin Buchbinder and Susan Godby Helzer

Center for Fire Research

Institute for Applied Technology

National Bureau of Standards

Washington, D.C. 20234

and

Fred L. Offensend

SRI International

333 Ravenswood Avenue

Menlo Park, California 94025

November 1977

Preliminary Report

U S. DEPARTMENT OF COMMERCE

NATIONAL BUREAU OF STANDARDS

NBSIR 77-1381

PRELIMINARY REPORT ON

EVALUATING ALTERNATIVES FOR

REDUCING UPHOLSTERED

FURNITURE FIRE LOSSES

Benjamin Buchbinder and Susan Godby Helzer

Center for Fire Research

Institute for Applied Technology

National Bureau of Standards

Washington, D.C. 20234

and

Fred L. Offensend

SRI International

333 Ravenswood Avenue

Menlo Park, California 94025

November 1977

Preliminary Report

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

CONTENTS

Page

LIST OF FIGURES lv

LIST OF TABLES iv

Abstract 1

1. INTRODUCTION 2

2. APPROACH 3

3. MODEL OVERVIEW 3

4. MODELING THE PROPOSED UPHOLSTERED FURNITURE STANDARD 6

4.1. Model Parameters and Probability Assignments 7 4.2. Results for the Proposed Standard 13

5. ADDITIONAL ALTERNATIVES 22

6. UNCERTAINTIES IN CALCULATED OUTPUT VALUES 23

7. CONCLUSIONS 23

8. REFERENCES 25
LIST OF FIGURES

Page

Figure 1. Probability tree for assessing upholstered

furniture fire losses 4

Figure 2. Cumulative probability distribution on aggregate

losses per reported fire under proposed upholstered

furniture standard with 90 percent compliance ... 15

Figure 3. Percentage of furniture population manufactured after

proposed standard becomes effective 18

Figure 4. Total annual aggregate dollar loss under proposed

upholstered furniture standard with 90 percent

compliance 19

LIST OF TABLES

Page

Table 1. Number of Fires for Current Conditions and Under

Fully Implemented Proposed Standard 8

Table 2. Probability Distributions on Extent of Flame

Damage for Current Conditions and Fully Implemented

Proposed Standard 10

Table 3. Expected Losses from Reported Fires Under Proposed

Standard (90% Compliance) in the Year 2010 17

Table 4. Estimated Cost, Loss, and Cost Plus Loss of the

Proposed Upholstered Furniture Standard (90%

Compliance) 21

IV
PRELIMINARY REPORT ON EVALUATING ALTERNATIVES FOR

REDUCING UPHOLSTERED FURNITURE FIRE LOSSES*

Benjamin Buchbinder, Susan Godby Helzer and

Fred L. Offensend2

Abstract

This paper presents preliminary results from a pilot project designed to test the utility of applying decision analysis

to fire hazard problems. To test the methodology, an analysis

is being performed to determine the effectiveness and economic

consequences of alternative Intervention strategies for

reducing upholstered furniture fire losses in residences. A

probabilistic model has been developed to assess quantitatively

the expected fire losses under each alternative. This paper

describes the analysis on one alternative: the proposed

upholstered furniture standard currently under consideration

by the Consumer Product Safety Commission. The loss model

for this alternative is described in some detail. Preliminary

results on costs, losses, and cost plus loss to society and

the present value of these quantities are presented.

A subsequent report will update this analysis with

revised data, and present a comparison of the proposed

standard with other alternative strategies.

Key words: Cost plus loss; decision analysis; fire; furniture

fire; losses; residential fire; standard; upholstered furniture.

This paper was originally presented as a talk at the Society of Fire

Protection Engineers Seminar, National Fire Protection Association

Annual Meeting held on May 18, 1977 in Washington, D.C. and will

be published by NFPA as a Technical Note.

Fred Offensend works for SRI International, 333 Ravenswood Avenue,

Menlo Park, California 94025.

1
1. INTRODUCTION

Policy makers in areas of public safety, including fire safety, are continually confronted with the need to select among several courses of

action in setting policy to reduce accidental losses. Such decisions

should be based on a systematic consideration of all benefits, risks, and

costs. However, because of the complexity of safety problems and the

uncertainties inherent in the evaluation of strategies for reducing

accidental losses, the choice among strategies is difficult. To assist

in this regard we are developing an analytical technique for use in

assessing the risks and avoided damages associated with different fire

safety alternatives. A comprehensive technique for assessing the total

economic costs of the different alternatives must also be developed.

These loss and cost assessments will then be combined in an analytical

framework to provide a systematic basis for choosing the most cost

effective strategy for addressing a particular fire problem.

This paper outlines an analytical framework for evaluating alternative intervention strategies for reducing upholstered furniture

fire losses. Although work on this project is continuing, enough

progress has been made to allow us to outline the basic structure of the

model and to demonstrate its potential for analyzing the consequences of

alternative strategies for reducing such losses. We illustrate the use

of the model by evaluating one possible intervention strategy: the

proposed upholstered furniture standard currently under consideration

by the Consumer Product Safety Commission. More complete documentation

of the model and the results of this analysis will be presented in a

3 forthcoming report [1] .

Numbers in brackets refer to references listed at the end of this

paper.

2
2 . APPROACH

The analytic framework is being developed using decision analysis.

Decision analysis is a formal methodology for analyzing complex decision

problems under uncertainty. The methodology employs quantitative models

developed expressly for each decision problem. These models are used to assess systematically the costs and losses that would occur under the

decision aJternatives in question. Uncertainty on key factors affecting

future losses is addressed with probabilistic methods.

The first step in the analysis is the development of a model of

current fire losses. Parameters are included in the loss model if they are important determinants of the overall losses, or if they are important in evaluating the change in losses expected under a particular

intervention strategy. Comparing the output of this model with current

loss statistics provides a useful consistency check on the logic and

data of the basic model. To estimate the losses under a particular

strategy, the model of current losses is modified to reflect the losses

expected under that strategy.

A separate model is developed to estimate the cost of each

intervention strategy. The cost and losses under each strategy are then assessed over time. All future values of cost and loss are then

discounted to obtain the present value of the cost plus loss under the

alternative in question. From an economic viewpoint, the most

attractive strategy is that which minimizes the cost plus loss to

society

.

3 . MODEL OVERVIEW

Figure 1 gives a schematic of the fire loss model, expressed in

the form of a probability tree. The model is used to calculate the

expected fire losses associated with a single upholstered furniture

3
IS A IS FIRE RESPON- IS THERE A DISCOVERED EXTENT

IS THERE IS SIBLE FUNCTIONAL BEFORE OF AN IS FIRE IGNITION SOMEONE PERSON SMOKE LEAVING FIRE FLAME

IGNITION 7 REPORTED 7 SOURCE HOME 7 AWAKE 7 DETECTOR 7 CHAIR 7 TYPE OAMAGE

DISCOVERED I'FL / R -e

DISCOVERED

OPEN FLAME

DISCOVERED

FUNCTIONAL

y. K/FL / R

1 > R —

s

DISCOVERED / SM/FL

DISCOVERED

FUNCTIONAL

-s

M FL / R

V

> R C —

s

t c

c

*/FL / R

\ >R —BE

-Fk

DISCOVERED M/FL /~~ R \ZH

-B

NOT

DISCOVERED * FL / R \-^R

FL / R L.-> R Figure 1. Probability tree for assessing

upholstered furniture fire losses

LOSSES

4
fire (sometimes referred to in the following text as "chair fire" for

brevity). The principal model parameters are listed across the top of

figure 1. The first nine parameters, from "is there an ignition?" to

"extent of flame damage," are the independent or causal variables in

the model. The last parameter listed, "losses" is the dependent or output variable of the model. Losses are characterized in terms of loss

of life, injury, property loss, and intangible losses. The logical and

computation flow of the model is from left to right.

The different branches under each of the parameters give the

possible values that the parameter in question might take on. For

example, the possible values of the ignition source parameter are "cigarette," "open flame," "electrical," and "other." The branch

values are defined so that they encompass all possible values for

the particular parameter.

Probabilities are assigned to the different branches to indicate

the likelihood of the particular parameter taking on the designated

value. The probability of a particular path through the tree is

calculated by multiplying the probabilities of the branches making up

that path. The losses associated with each path are derived from

fire incident data, adjusted by expert judgment where necessary.

These are average or expected losses. By combining the probability

of each path with its corresponding losses and tracing all the paths

of the tree, we construct a probability distribution on the expected

losses per fire that would occur under the particular intervention

strategy. We then combine this distribution with the annual number of

upholstered furniture fires in the United States to obtain the probability

distribution of total upholstered furniture fire losses.

First, current losses are modeled. Next, losses under each

alternative strategy are modeled at a future time when that strategy

has become fully implemented. The losses for each alternative are

5
then modeled for each intervening year by combining the current losses

with the losses under the fully implemented strategy in the appropriate

way

.

A cost model is used to calculate the total cost of each

alternative. The model encompasses all direct and indirect costs

including costs of development, implementation, compliance and

enforcement. Costs for a given alternative are modeled for each year

of interest. Expected costs and losses for each alternative are then

combined, with appropriate discounting, and accumulated over time. When

this has been done for each strategy, the cost plus loss comparison is

made

.

4. MODELING THE PROPOSED UPHOLSTERED FURNITURE STANDARD

To illustrate the methodology for evaluating alternatives, we

now use the model to assess losses and costs under one alternative:

the upholstered furniture standard currently under consideration by

the Consumer Product Safety Commission. The proposed standard is aimed

at reducing smoldering ignitions of upholstered furniture, primarily

those caused by cigarettes. Combinations of upholstery and furniture

construction which can be ignited by cigarettes are not permitted under

the proposed standard.

Using the current loss model as a basis, new probability assignments

are made for certain parameters on the probability tree shown in figure 1

to reflect expected losses under the fully implemented proposed standard.

Probability assignments for the model of both current losses and losses

under the proposed standard are developed using a combination of fire

loss data and expert judgment. The data on current fire losses come primarily from the National Fire Incident Reporting System (NFIRS) at

the National Fire Prevention and Control Administration. The judgment

comes primarily from fire technology experts at the Center for Fire

Research at the National Bureau of Standards. This judgment is then

6
encoded into probabilities and combined with fire loss data as input

to the fire loss model shown in figure 1.

We must emphasize that the primary purpose of this project has

been to develop and demonstrate methodology. The probability and loss

assignments, whether from data or judgment, are strictly preliminary

and will be revised as more extensive information becomes available.

The reader is thus cautioned against drawing any firm conclusions from

this presentation as to the actual costs or benefits of the proposed

upholstered furniture standard.

4.1. Model Parameters and Probability Assignments

We now model the fire losses for the case in which the current

upholstered furniture population is replaced by a new furniture population fully compliant with the proposed standard. We show how the

probability assignments for current losses (values to be documented in our full report) are adjusted to obtain new probability assignments for

the fully implemented proposed standard. We consider each model parameter displayed in figure 1, determine if it is affected, and if so how.

We first discuss those model parameters, affected by changes in the

furniture population: "is there an ignition?," "ignition source,"

"fire type," and "extent of flame damage."

The column of table 1 gives the current number of ignitions by

ignition source and ignition type (smoldering or flaming) . Using a 1974 household fire survey [2], we estimate that there are currently

110 000 fires annually in which upholstered furniture was the first

item ignited. This is the total of column 1, table 1. Based on NFIRS

4 fire incident data from over 2700 upholstered furniture fires , we set

the current ignition source probabilities to the following: cigarette -

0.70, open flame - 0.13, electrical - 0.05, and other - 0.12. We

4 Fires in one and two family homes and apartments in which upholstered

furniture was the first item ignited from Ohio (1976) and California

(1975). Incendiary and suspicious fires were excluded.

7
Table

1.

Number

of

Fires

for

Current

Conditions

and

Under

Fully

Implemented

Proposed

Standard 8

TOTAL

110

000 8

008 8

008

1.000
then apply expert judgment to estimate the proportion of smoldering

and flaming ignitions for each ignition source. Combining the 110 000

ignitions with the ignition source probabilities, and the judgment on ignition type, we obtain the numbers shown in column 1.

The principal effect of the proposed standard would be to reduce

the number of ignitions, particularly smoldering ignitions. The

second column of table 2 gives the proportion of current smoldering

and flaming ignitions for each ignition source anticipated under the

proposed standard, as determined by expert judgment. For example, with

a fully compliant furniture population the experts predict essentially

no cigarette ignitions, an 80% decrease in smoldering electrical

ignitions and a 30% decrease in flaming electrical ignitions. The

entries in the third column are the estimated number of ignitions under

the standard by ignition source and type. They are obtained by taking

the products of the entries in columns 1 and 2. The total of this

column, 8008, is the expected number of ignitions under the fully

implemented standard. Dividing 8008 by 110 000, the current number

of ignitions, we find that the probability of ignition occurring under

the fully implemented standard is 0.0728 times the current ignition

probability.

Column 4 of table 1 displays the estimated number of ignitions for

each ignition source, which is the sum over both ignition types for

that source. Normalizing, the new probability distribution on ignition

source shown in colume 5 is obtained.

The next model parameter affected by the changing furniture

population is the "fire type," a combination of both ignition type

and fire development. Three fire types are considered: initially

smoldering (SM) , initially smoldering and later flaming (SM/FL) , and

directly flaming (FL) . The numbers in column 3 of table 1 are used

9
Table

2.

Probability

Distributions

on

Extent

of

Flame

Damage

for

Current

Conditions

and

Fully

Implemented

Proposed

Standard

10
to obtain the proportion of smoldering and flaming ignitions for each

ignition source. These proportions are then used, in combination with

fire development data, to obtain revised distributions on fire type

for the proposed standard.

The final model parameter directly Influenced by the changing

furniture population is the "extent of flame damage." This parameter

can take on three values: confined to the chair (C) , beyond the chair

but confined to the room (R) and beyond the room (>R) . The probability

assignments for current conditions, shown in table 2, are based on NFIRS data adjusted by judgment to make the assignments conditional on the parameter "is fire discovered before leaving chair?" Under the

fully implemented proposed standard, somewhat larger fires are likely

to result once an ignition has occurred. This effect is primarily the

result of the natural evolution of the furniture population toward

greater use of urethane foam. To model this effect expert judgment is

used to adjust the current flame extent probabilities to obtain the

new probability assignments shown in table 2.

It is useful to digress here to emphasize that as we move from

left to right through the probability tree, the probability assignment

on each branch is conditional on the values of the parameters on the

preceeding branches. Thus the details on some of the probability

assignments are too lengthy for this report. Note that from the

"ignition source" parameter on, the tree is in reality four times as large as it appears because only the "electrical" ignition source branch is continued on figure 1. We now return to our discussion of

the fully implemented proposed standard, to look at the other model

parameters affected.

11
The increasing voluntary installation of smoke detectors is

expected to reduce fire losses significantly. We assume that 5% of

the households in the United States currently have a functional smoke

detector. Eventually about 60% of U.S. households are expected to

have smoke detectors through voluntary installation or code requirements for new construction. We assume this level will be reached by

1980. We further assume that 90% of these will be working at a particular time. Thus to model the fully implemented proposed standard, the

parameter "is there a functional smoke detector?" is set to 0.60 x 0.90 = 0.54.

Finally, the probability assignment on "is fire reported?" is

adjusted. A separate inference structure has been developed to compute

that the probability that an upholstered furniture fire is reported

to the fire department is 0.29 under current conditions and 0.51 under

the fully implemented standard. ^ Only reported fires are explicitly

considered by the model at present because even though many fires are not reported to the fire department, reported fires account for the

great majority of the losses. In addition most statistical data are based on reported fires. Losses from unreported fires will be added

to the model later on for completeness, although this refinement is

not expected to be of great significance.

The other model parameters "is someone home?", "is a responsible

person awake?" and "is fire discovered before leaving chair?" are not

affected by the proposed standard. Thus the current probability

assignments are used.

Loss estimates are made for each path through the tree. Four

categories of loss are considered: fatality, injury, tangible property

and intangible property. The loss assignments are made dependent on

For the details on this calculation, and on others not fully explained,

the reader is referred to the forthcoming complete report on the

analysis

.

12
the extent of flame damage, and whether or not the fire was discovered

before it left the chair. In addition human losses are also made

dependent on whether or not someone was home at the time of ignition.

Loss assignments for deaths, Injuries and tangible property loss for

each extent of flame damage category are initially derived from NFIRS

data. These assignments are then modified by expert judgment to

reflect the dependencies discussed above. Estimates, based on expert

judgment, are also introduced to reflect intangible fire losses such

as disruption of lifestyle and loss of family heirlooms.

Loss assignments are given in terms of number of deaths and

injuries and dollars of property loss. Alternatives can be compared by

separately considering each loss category. However, since it is

difficult to compare several outcome factors at one time, value

assignments are introduced to aggregate all losses using a common monetary scale. For the purpose of this analysis we use nominal

assignments of $300 000 as the amount society is willing to pay to save a single life and $10 000 for the economic loss due to an average

fire injury. The current loss assignments are also used to model

g each alternative including the fully implemented proposed standard.

4.2. Results for the Proposed Standard

Thus far we have presented input data for the case of 100%

compliance with the proposed standard; however, we assume that in

practice only 90% of the furniture produced under the proposed standard

will be fully compliant. Ten percent of the furniture is assumed to be

non-compliant because of such factors as the use of slip covers, poor

quality control in the manufacturing process and loss of ignition

resistance due to soil and wear. To model this compliance level, we

For simplicity, all calculations are performed using 1977 dollars.

13
take a weighted average of the above losses for the fully compliant

case and the losses expected for upholstered furniture which does not

meet the proposed standard. Losses for the case of 90 percent compliance

with the proposed standard are given in figure 2.

Figure 2 gives the cumulative probability distribution on the

aggregate losses associated with a single reported upholstered furniture

fire. Aggregate losses include deaths, injuries, tangible and intangible

property loss, all measured in dollars. The probability distribution is

constructed by first following the ignition and reported branches, and

from that point the probability of each path through the tree is

calculated. Associating each path probability with its corresponding

aggregate loss figure, we obtain the dollar loss distribution shown.

The expected value of the probability distribution is calculated by

multiplying the aggregate loss for each path by its probability and then

summing. This calculation gives an expected aggregate loss of $13 500

per reported fire, under the proposed upholstered furniture standard.

Total annual expected U.S. losses are found by multiplying the

expected losses per reported fire by the expected number of reported

fires. Assuming 90 percent compliance with the proposed standard the

total number of ignitions is found to be 14 800 of which 5 800 are reported. (These numbers are appropriately weighted averages of the

corresponding numbers for the fully compliant proposed standard case and

the case in which no standard has been imposed.) Multiplying the number

of reported fires per year by the expected total loss per reported fire

gives an expected total annual loss of $78 million for the case of 90

percent compliance with the proposed standard.

The fire loss model can also be used to develop probability

distributions and loss statistics on individual categories of loss.

The calculations are carried out exactly as in the case of aggregate

loss, except that instead of using aggregate loss values for each

path on the tree, we use the losses for the particular loss category.

14
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15

LOSSES

(Thousands

of

Dollars)
Table 3 gives the expected losses per reported fire for each of the

four categories of loss. Multiplying the expected numbers of fatalities

and injuries per fire by 5 800, the annual number of reported fires, gives

an expected annual number of 120 deaths and 760 injuries for the case of

90 percent compliance with the proposed standard.

The results just presented reflect a furniture population all of

which has been manufactured under the proposed standard (at a 90%

compliance level). However, it will take years to completely replace

the current furniture population with this newly manufactured furniture.

Figure 3 shows the percentage of chairs in the total furniture population

produced after the standard takes effect. Using 1980 as year in which

the proposed standard is implemented, we calculate that by the year 2010

essentially all of the "pre-standard" furniture will be replaced by

"post-standard" furniture thus achieving the 90% compliance level. Losses

for the years 1980 to 2010 are found by interpolation. The interpolation

is accomplished by obtaining the fraction of pre-standard and post-standard

furniture for each year from figure 3 and then taking the appropriate

weighted average of the corresponding losses. To calculate expected

losses for the years 1975 to 1980, before the standard goes into effect,

both increased smoke detector installation and naturally evolving changes

in the furniture population are considered.

Figure 4 shows that relative to current losses substantial loss

reductions may be expected from the proposed standard. Current aggregate

losses (for 1975) are estimated at $455 million annually. The decline in

annual loss, prior to 1980, is primarily due to voluntary and locally

mandated installation of smoke detectors. After 1980 the losses decrease

as more and more furniture becomes compliant with the proposed standard.

By the year 2010, the 90 percent compliance level is reached with

resulting aggregate losses of $78 million annually.

16
Table 3, Expected Losses from Reported Fires Under Proposed

Standard (90% Compliance) in the Year 2010

Expected Loss Per Reported Fire*

Category Number Dollar Value

Fatalities 0.0208 $ 6 240

Injuries 0,131 1 310

Property

Tangible

Intangible

5 120

840

Aggregate $13 500

*5 800 of the Estimated 14 800 Fires Under the Proposed

Standard Would be Reported in the Year 2010

17
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CC

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(/)

103dd 3 Nl aaVONVlS d31dV

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18

Figure

3.

Percentage

of

furniture

population

manufactured

after

proposed

standard

becomes

effective.
400

O

CNJ

in

o

o

CM

o

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19

Figure

4.

Total

annual

aggregate

dollar

loss

under

proposed

upholstered

furniture

standard

with

90

percent
Our major modeling effort thus far has been directed towards

assessing fire losses. Nevertheless, our criterion of minimum cost plus

loss requires that we include the expected costs as well, and finally

that we compare cost plus loss among all alternative strategies.

Work is currently under way at the National Bureau of Standards to

develop a comprehensive cost model for the proposed standard [3]. To

obtain a preliminary estimate of the annual cost of the proposed

standard we use a Center for Fire Research estimate of $256 million

annually [4]. This figure includes the cost increase at retail, in 1977

dollars of upholstery fabrics, construction materials and flammability

testing. This estimate does not include the costs of record keeping,

research and development, and enforcement. To account for these

additional costs we add $25 million to the $256 million to obtain a preliminary estimate of $281 million for each year the standard is in

effect

.

Table 4 gives the cost plus loss of the proposed upholstered

furniture standard for selected years. The total cost plus loss to

society is calculated from the losses and costs outlined above. The

reader is again cautioned, however, that these losses and costs depend

upon nominal probability assignments, as well as nominal costs and loss

assumptions. Many of these assignments and assumptions are preliminary,

and are currently being refined and updated. Others are, and will remain,

largely subjective. These considerations make the decision analysis

methodology used here most useful in comparing alternatives, rather than

obtaining absolute estimates of the cost plus loss. Thus the results

presented in table 4, as well as figure 4, should be interpreted as illustrative of the decision analysis methodology rather than absolute

estimates of the losses, costs, and cost plus loss under the proposed

standard

.

As shown in table 4, the cost plus loss of the proposed upholstered

furniture standard is $455 million in 1975. When the standard takes

effect in 1980 the cost plus loss reaches $608 million because the

20
Table 4. Estimated Cost, Loss, and Cost Plus Loss of the Proposed

Upholstered Furniture Standard (90% Compliance)

Year

Cost Loss Cost Plus Loss

(Millions of Dollars)

1975 $ 0 M $ 455 M $ 455 M

281 327 608

281 175 456

281 85 366

281 78 359

1980

1990

2000

2010

Present

Value* $1990 M $2925 M $4915 M

*Discounted at 10% to 1977

21
first year's cost of implementing the proposed standard are included.

The cost plus loss then decreases due to the decreasing losses (shown

in figure 4). A constant annual level of $359 million cost plus loss

is attained by 2010 when the 90% compliance level is reached.

Also given in table 4 is the present value of the cost plus loss

discounted at a 10 percent rate to 1977. The present value is an accumulation of the costs and losses over the entire period, 1977-2010,

obtained by discounting the costs and losses of future years at a 10

percent compound interest rate and then summing. The table shows that

the present value of the expected cost plus loss at a 10 percent

discount rate is $4.9 billion.

5. ADDITIONAL ALTERNATIVES

Work is currently underway on modeling two other alternative

strategies. One is called the "no action" alternative under which we assume that no formal intervention strategy will be implemented, but

that voluntary purchases of smoke detectors will also reach a 60 percent

installation rate in 1980. This alternative also assumes that the

furniture population will evolve toward the mix that is currently being

produced, as opposed to that which is currently in our homes. The second

alternative involves a mandatory requirement for the installation of

smoke detectors in all U.S. residences. The evaluation of this

alternative is based on the same furniture population as the no action

alternative. Other alternatives such as a voluntary upholstered furniture standard, modifying the burning behavior of cigarettes, specially

targeted public education programs, or combination of alternatives may

also be considered. In each case the costs and losses will be computed

over time in a manner similar to that for the proposed standard. At

this point no comparison of alternatives has been made pending the

completion of the initial analysis of the other alternatives.

22
6. UNCERTAINTIES IN CALCULATED OUTPUT VALUES

The results just presented were based on nominal estimates for the

various input data assignments. We carry out an analysis on the

sensitivity of the calculated output variables to uncertainties in the

input estimates. In performing a sensitivity analysis, we use the model

to generate cost-plus-loss values, assuming different values for the

various input data. In this manner we bound our uncertainties on parameter assignments and examine the effect of changing given parameters to extreme values which they might take on. Initial sensitivity

analyses serve to screen the parameters, and identify those for which

our degree of uncertainty is too great to permit a clear choice among

alternatives. In these instances we weigh the cost of obtaining better

data against the improvement in our ability to distinguish between

alternatives

.

The forthcoming report on the complete analysis contains considerable sensitivity analysis. It should be stressed that the methodology

is designed to measure differences among alternatives rather than to

estimate exact values of cost and loss.

7. CONCLUSIONS

The purpose of this paper has been to provide preliminary documentation of a decision analytic approach for evaluating alternative intervention strategies for reducing upholstered furniture fire losses. We

have not attempted to document the detailed calculations and assumptions

for the fire problem involved, but rather to illustrate how it is possible to address systematically the uncertainties that combine to affect

fire losses.

23
A comprehensive evaluation of alternatives requires the incorporation of value judgments as a fundamental step. To evaluate alternatives

directed toward reducing injuries and fatalities, values are assigned

to the amount that society is willing to pay to avoid an average fire

injury or save a single life. There is a large body of literature and

substantial difference of opinion regarding these value assignments.

Our pilot analysis uses nominal values for injury and loss of life,

as well as nominal discount rate, to illustrate the cost plus loss

computation. Hard conclusions, based on these nominal assignments,

should not be drawn from the results presented at this time. Our

methodology, and the orderly structured analysis it provides, should

provide significant input to the decision makers ultimately responsible

for reducing fire losses in the public interest.

The emphasis of the project to data has been on methodology

development and on the pilot application of that methodology to a sample

problem. We are currently in the process of completing the analysis of

the upholstered furniture fire problem, and we will document that work

in a complete final report. We regard decision analysis as an important

tool in fire hazard analysis, and we plan to apply this approach to other

problems of fire safety, including mobile home fires.

24
8 . REFERENCES

[1] Offensend, F. L., Helzer, S. G. and Buchbinder, B. , Decision

Analysis of Strategies for Reducing Upholstered Furniture Fire

Losses. In preparation.

[2] Unpublished data from a survey of over 33 000 U.S. households

co-sponsored by the National Bureau of Standards and the

Consumer Product Safety Commission and conducted by the Bureau

of Census (1974).

[3] Muehlhause, C. 0., A Cost Benefit Framework for Consumer Product

Safety Analysis. In preparation.

[4] Howard D. Tipton to John S. Byington, Upholstered Furniture

Standard, Smoke Detector8, and Fire Prevention and Control

Strategy .

25
U.S. DEPT. OF COMM. BIBLIOGRAPHIC DATA

SHEET

1. PUBLICATION OR REPORT NO. NBSIR 77-13812. Gov’t Accession

No.

3, Recipient’s Accession No.

4. TITLE AND SUBTITLE

PRELIMINARY REPORT ON EVALUATING ALTERNATIVES FOR REDUCING

UPHOLSTERED FURNITURE FIRE LOSSES

5. Publication Date November 1977

6. Performing Organization Code

7. A UTHOR(S)

Benjamin Buchbinder, Susan Godby Helzer, Fred L. Offensend

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. 4913679

11. Contract/Grant No.

12. Sponsoring Organization Name and Complete Address (Street, City, State, ZIP)

Same as No. 9

13. Type of Report & Period Covered

Preliminary Report

14. Sponsoring Agency Code

15. SUPPLEMENTARY NOTES

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

bibliography or literature survey, mention it here.) This paper presents preliminary results from a pilot project designed to test the

utility of applying decision analysis to fire hazard problems. To test the

methodology, an analysis is being performed to determine the effectiveness and

economic consequences of alternative intervention strategies for reducing upholstered

furniture fire losses in residences. A probabilistic model has been developed to assess quantitatively the expected fire losses under each alternative. This paper

describes the analysis on one alternative: the proposed upholstered furniture

standard currently under consideration by the Consumer Product Safety Commission.

The loss model for this alternative is described in some detail. Preliminary

results on costs, losses, and cost plus loss to society and the present value of

these quantities are presented.

A subsequent report will update this analysis with revised data, and present a comparison of the proposed standard with other alternative strategies.

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) Cost plus loss; dec ision analysis; fire; furniture fire;

losses; residential fire; standard; upholstered furniture.

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