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1
FIRE DEATHS IN THE UNITED STATES
SCOPE OF THE PROBLEM
As a cause of accidental death in the United States,
fire is exceeded only by automobile collisions, falls,
and drowning.26 The United States and Canada have the
highest absolute numbers of fire-related deaths in the
world and fire-death rates generally 2-4 times those in
Europe.~98 The United States also has one of the
highest per capita fire rates. 2 2 2
U.S. fire deaths have been decreasing for the last 20
years, with an overall decrease of about 35% in that
period (Figure 1-1). When adjusted for population, the
decrease is even more marked--approximately 42% since the
early 1950s (Figure 1-2). Throughout the latter period,
fires in the home accounted for an average of more than
75% of all fire deaths (Figures 1-1 and 1-2).
Most fire deaths occur in one- or two-family dwellings
and apartments (Table 1-1). People are most at risk of
dying in a fire when they are sleeping6 2 or when their
ability to escape is otherwise impaired. In a common
type of residential fire, death occurs at night, 2 6
results from the ignition by cigarette of upholstered
furniture or bedding (Table 1-2), and involves
intoxicating amounts of alcoholic beverages. 3 5
Although most fire deaths occur in residences (one or
two per fire), the fires that seem to attract public
attention are the dramatic and catastrophic ones that
result in the loss of many lives. According to the
National Fire Protection Association (NFPA), reported
15
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16
9
8
~5
In
i.
o
v,
~ 6
7
art....
/l\\/\l\
\ Total
Irk
\,~\ Home ~
W/~~ \
5 _ '\r\/
4
~ I 1 1 1 ,
1 1
1950 1960 1970 1980 1985
Year
FIGURE 1-1 Fire deaths in the United States, 19S0-1980,
total and home. (Data do not include transport-related
Data from National Center for Health
fire deaths.)
Statistics. 6 0
Census data for 1968 are missing.
multiple-death fires (those which resulted in three or
more deaths per fire) caused 16.4% of the fire deaths in
1984. On the basis of NFPA data for 1980-1984, loss of
life in multiple-death fires has decreased, owing to a
reduction in the number of these incidents, rather than
in their severity. 62
CAUSES OF FIRE DEATH
Accurate data on the causes of deaths associated with
fire are difficult to obtain Autopsy is the only means
available to determine the cause of death conclusively
(i.e., smoke inhalation versus burns), but it does not
always provide more definitive information--e.g., was
death due to carbon monoxide (CO), to some other
toxicant, or to a combination of toxicants? Finally,
autopsy is not usually ordered in cases of fire death.
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17
5
4
o
0
0
o
lo
-
it.
~ ~ \~~..
O L I I I I I I I
1950
.,
..
~ Total
Home
1 960
1 970
Year
1980 1 985
FIGURE 1-2 Fire deaths per 100,000 population in the
United States, 1950-1980, total and home. (Data do not
include transport-related fire deaths.) Data from
National Center for Health Statistics.i 6 o Census data
for 1968 are missing.
It is generally accepted that 70-80% of fire deaths
result from smoke inhalation. 3 S ~ 3 5 Smoke, as defined
by the American Society for Testing and Materials, 3 is
n the airborne solid and liquid particulates and gases
evolved when a material undergoes pyrolysis or combus-
tion. n Indeed, a comprehensive study of fire deaths,
performed by the Applied Physics Laboratory of The Johns
Hopkins University on the basis of data from Maryland,
found that CO, a toxic gaseous component of smoke, was
the cause or a contributing cause of 80% of fire deaths
(Table 1-3). Alcohol was involved in 40% of deaths.
CO, produced by all fires as a component of smoke, is
often considered to be the major toxicant produced by
fires; it acts by binding to red blood cells and forming
carboxyhemoglobin (COHb), which interferes with oxygen
transport. In studies of fire death, COHb concentrations
of 50-60% are generally accepted as fatal. 3 5 ~ 9 4 (For a
complete discussion of CO toxicity, see Chapter 4.)
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18
TABLE 1-1
Fire Deaths by Property Use,
United States, 1984a
Property Use
Residential (total):
One- and two-family
dwellings
Apartments
Hotels and motels
Other residential
Nonresidential structures
Highway vehicles
Other vehicles
Other
Total
aData from carter. 5
Estimated
Number of
Civilian
Deaths
4,240
3,290
785
120
45
285
530
100
85
5,240
Fraction
of
Civilian
Deaths,
80.9
62~8
15.0
2.3
O.9
5.4
10.1
1.9
1.6
99.9
Besides CO, smoke contains carbon dioxide and can contain
oxides of nitrogen, hydrogen cyanide (HCN), hydrogen
chloride, sulfur dioxide, acrolein, benzene, phenol, and
other compounds.~9 2 These substances, individually or
in combination with each other or with CO, can cause
immediate or delayed death. They can also impede escape
from fire, and thereby increase risk of death, by
obscuring vision as a result of eye irritation and
lacrimation, by impairing mobility, or by impairing
mental acuity.
The possibility that toxic gases other than CO cause
fire-related deaths has been investigated in several
studies. Analysis of samples from 80 victims of the MOM
Grand Hotel fire 3 6 revealed that approximately half the
victims had COHb concentrations less than 50%; that raises
the question of which other toxic factors might have con-
tributed to these deaths. Investigations of a jail fire
in Johnson City, Tennessee, 37 and of Maryland fire deaths
over a 42-month period 3 5 discovered potentially toxic
concentrations of HCN in the blood of a number of victims.
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19
TABLE 1-2
Major Residential Fire-Death Scenariosa
Item Ignited
Fraction of U.S.
Ignition Source Fire Deaths, %
Furnishings Smoking 27
Trash, apparel Smoking 4
Furnishings, flammable Open flame 11
liquids, apparel
Furnishings, flammable Heating and 13
liquids, apparel, cooking
interior finish equipment
Structural materials, Electric 4
interior finish equipment
Flammable liquids, Other 7
apparel
Other scenarios, each Variable
less than 2% of total 34
100
aData from Benjamin/Clarke Associates, Inc. 32
High HCN concentrations, however, were always associated
with high (not necessarily lethal) CO concentrations.
Surveys of fire victims in Glasgow have confirmed this,
in that both survivors and nonsurvivors had substantial
quantities of cyanide in their blood after the
fire. 49
Eighteen of the 23 victims of the Air Canada cabin
fire in 1983 had sublethal COHb concentrations (less than
50%). Blood concentrations of HCN, however, were lethal
in 14 or 19 of the victims, depending on whether one
assumes a fatal concentration of HCN to be 1.0 or 2.0
~g/ml. 3 8 That a number of survivors breathed through
wet towels supports the inference that HCN, a hydrophilic
agent, was a major factor in causing death. Breathing
through wet fabric can in principle reduce the concen-
tration of hydrophilic compounds, but not of CO. However,
it is not known how many of those who died also breathed
through wet towels. (High fluoride concentrations were
also found in the victims' blood. The toxicologic sig-
nificance of the observed concentrations, however, was
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20
TABLE 1-3
Causes of Fire Deaths (530 Cases)a
Cause of Death
CO aloneb
CO plus cardiovascular disease
Burns
Unexplained
Total
aData from Birky et al.35
bCarboxyhemoglobin content over 50%.
Fraction of Deaths,
60
20
11
9
100
not established. Exposure to hydrogen fluoride, a
hydrophilic acid gas, could also have been reduced by
breathing through wet fabric.)
THE CONTEMPORARY FIRE ENVIRONMENT
Findings like those just described, combined with a
growing public awareness of the toxic hazards associated
with fire, have led to the belief that today's fires
produce combustion products that are more toxic than the
fires of 30 or 40 years ago. Some assume that the
increased presence of synthetic materials in the built
environment causes fires to burn hotter and faster and to
produce more toxic smoke than ever before. Although
synthetic materials are more prevalent in our work and
residential environments than they were 40 or even 20
years ago (Figure 1-3), the national fire-death rate has
decreased over the last 30 years. No single factor can
explain this trend. For example, the decrease might
reflect recent decreases in fire incidence, improvements
in firefighting techniques, changes in building fire
codes, and the use of home smoke detectors.
Although it is possible to document the cause of death
in fire victims and potentially possible to identify
through pyrolysis/mass spectrometry3 8 the sources of
the combustion products inhaled by victims, such studies
are infrequent. And the existing data cannot be used to
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21
2,000
cn
o
° 1,000
a
. _
. _
_
/
//
PVF /
IMPS:
PVC
/
/ //
/
PVF
PS
PVC
1950 1960 1970 1980
Year
FIGURE 1-3 Production of poly(vinyl chloride), poly-
styrene, and polyurethane. PUF = total polyurethane
production; data from Society of the Plastics Industry. 2 o 7
PS = molded polystyrene production for selected consumer
markets; data abstracted from Modern Plastics. 49-~52
PVC = poly(vinyl chloride) film production for selected
consumer markets data abstracted from Modern
Plastics. l 4 9 - l 5 2
determine trends, because comparative data from the
presynthetic era (before 1950) are not available. Post-
mortem examination of fire victims for pathologic evidence
of exposure to such irritants as HC1 is a fairly new
practice; and some techniques for measurement of combus-
tion products, such as atomic-absorption spectroscopy for
detection of heavy metals and gas chromatography for
measurement of blood cyanide, have become widely available
only recently.
In view of the lack of comparative-pathology studies
and of death-rate trends, there is little evidence that
modern fires present a greater risk of death than fires
of 30 or 40 years ago--either residential fires or large
multiple-death fires, such as the Cocoanut Grove fire of
1943.
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22
The hypothesis of a greater toxic hazard in contempo-
rary fires might be tested by collecting prospective
epidemiologic evidence and exploring potentially variable
postexposure health effects in survivors of fires of
different kinds. For example, evidence of a change in
smoke toxicity could appear as an increased incidence of
some pulmonary complications in those exposed to fires
that involved greater amounts of synthetic materials.
Data for such a study could be drawn from hospital
records, insurance-company records, firefighter-
association statistics, and so forth.
Many factors impinge on the fire problem in the United
States; the change in the fuel load of the built environ-
ment is only one of them. However, whatever the cause of
death, the United States has the highest fire-death rate
in the world. An improved understanding of the hazards
associated with fires, including toxic hazards, will
certainly assist all who must deal with fire and its
consequences, be they fire-safety engineers, firefighters,
medical personnel, or those who find themselves threatened
by fire.
Representative terms from entire chapter:
combustion products
