1 | Page

Non-Fire Carbon Monoxide Deaths

Associated with the Use of Consumer Products

2009 Annual Estimates

Matthew V. Hnatov

U.S. Consumer Product Safety Commission

Directorate for Epidemiology

Division of Hazard Analysis

4330 East West Highway

Bethesda, MD 20814

December 2012

This analysis was prepared by the CPSC staff, has not been reviewed or approved by, and may not necessarily 

reflect the views of, the Commission.
2 | Page

Table of Contents

Executive Summary.......................................................................................................................................................3

Introduction ...................................................................................................................................................................6

National Estimates of Non-Fire CO Poisoning Deaths Associated with Consumer Products.......................................7

Table 1: Estimated Non-Fire Carbon Monoxide Poisoning Deaths by Associated Fuel-Burning Consumer 

Product, 1999–2009.................................................................................................................................................10

Table 2: Estimated Non-Fire Carbon Monoxide Poisoning Deaths Associated with Consumer Products Organized 

by Fuel Type, 1999–2009........................................................................................................................................13

Table 3: Estimated Non-Fire Carbon Monoxide Poisoning Deaths Associated with Engine-Driven Tools, 1999–

2009 .........................................................................................................................................................................16

Figure 1: Comparison of Trends in Consumer Product-Related Carbon Monoxide Deaths – 1999 to 2009..........18

Table 4: Number of Carbon Monoxide Poisoning Incidents Reported to CPSC by Number of Deaths Per Incident, 

1999–2009 ...............................................................................................................................................................19

Table 5: Estimated Non-Fire Carbon Monoxide Poisoning Deaths by Location of Death, 1999-2009..................20

Table 6: Estimated Non-Fire Carbon Monoxide Poisoning Deaths by Month of Year of the Fatality, 1999–2009

.................................................................................................................................................................................21

Figure 2: Estimated Number of Consumer Product-Related Carbon Monoxide Deaths by Month of Death, 1999–

2009 .........................................................................................................................................................................22

Demographics of Fatalities from Non-Fire Carbon Monoxide Poisoning Associated with the Use of Consumer 

Products.......................................................................................................................................................................23

Table 7: Estimated Non-Fire Carbon Monoxide Poisoning Deaths by Age of Victim, 1999–2009.......................23

Table 8: Estimated Non-Fire Carbon Monoxide Poisoning Deaths by Gender of Victim, 1999-2009 ..................24

Table 9: Estimated Non-Fire Carbon Monoxide Poisoning Deaths by Race/Ethnicity, 1999-2009.......................25

Table 10: Estimated Non-Fire Carbon Monoxide Poisoning Deaths by Population Density of Place of Death, 

1999–2009 ...............................................................................................................................................................27

Appendix A: Methodology.........................................................................................................................................29

Table A.1.a: Initial Categorization for 2007 Data ..................................................................................................31

Table A.1.b: Initial Categorization for 2008 Data ..................................................................................................31

Table A.1.c: Initial Categorization for 2009 Data ..................................................................................................31

Table A.2.a: Calculation Detail of the Final Computed 2007 Estimate of Non-Fire CO Poisoning Deaths 

Associated with Consumer Products .......................................................................................................................32

Table A.2.b: Calculation Detail of the Final Computed 2008 Estimate of Non-Fire CO Poisoning Deaths 

Associated with Consumer Products .......................................................................................................................33

Table A.2.c: Calculation Detail of the Final Computed 2009 Estimate of Non-Fire CO Poisoning Deaths 

Associated with Consumer Products .......................................................................................................................33

Table A.3: CO Fatality Cases and Weighting Factors Used to Calculate the Estimates for the Years 1999–2009 34

Appendix B: National Estimates of Consumer Product-Related CO Poisoning Deaths, 1980 to 2009......................36

Figure B.1: Estimated Non-Fire CO Poisoning Deaths Associated with Consumer Products: 1980–2009...........36

Table B.1: Estimated Non-Fire Carbon Monoxide Poisoning Deaths Associated with Consumer Products, 1980-

2009 .........................................................................................................................................................................37

Table B.2: Estimated Non-Fire Carbon Monoxide Poisoning Deaths Associated with Generators, 1999-2009....38

Table B.3: Estimated Non-Fire Carbon Monoxide Poisoning Deaths Associated with Consumer Products, 1999–

2009 (Excluding Generator-Related Deaths)...........................................................................................................39

Table B.4: Estimated Non-Fire Carbon Monoxide Poisoning Deaths Associated with Generators and Other 

Engine-Driven Tools, 1999–2009............................................................................................................................40

Table B.5: Estimated Non-Fire Carbon Monoxide Poisoning Deaths Associated with Consumer Products, 1999-

2009 (Excluding Generator- and Other Engine-Driven Tool-Related Deaths)........................................................41

Appendix C: Regional Definitions .............................................................................................................................42

References ...................................................................................................................................................................43
3 | Page

Executive Summary

This report provides information about the estimated number of unintentional non-fire 

deaths attributed to carbon monoxide (CO) poisoning that were associated with the use of 

consumer products in 2009, and companion statistics since 1999. It should be noted that CPSC 

staff continues to receive reports of CO poisoning fatalities, and the estimates may change in 

subsequent reports. 

Some of the key findings in this report are:

For 2009:

• There were an estimated 146 unintentional non-fire CO poisoning deaths associated with 

consumer products under the CPSC’s jurisdiction. The estimated annual average from 

2007 to 2009 was 169 deaths.

1

• Engine-Driven Tools (EDT) were associated with the largest percentage of non-fire CO 

poisoning fatalities at 53 percent (estimated 77 deaths). Heating Systems-related CO 

fatalities were associated with 27 percent (40 deaths), and the remaining six product 

categories [Charcoal Grills or Charcoal (7 deaths), Ranges, Ovens (3 deaths), Water 

Heaters (5 deaths), Lanterns – LP Fueled (1 death), Other Products (2 deaths), and 

Multiple Products (11 deaths)], combined were associated with a total of 20 percent. In 

2009, there were no reported deaths in the Grills, Camp Stoves category.

Generators & Other Engine-Driven Tools2

:

• There were an estimated 79 CO fatalities in 2009 that were associated with EngineDriven Tools, including 2 of the 11 Multiple Products deaths in which an EDT and 

another potential CO-producing product was also in use. Sixty-seven of the 79 EDTrelated deaths (including both of the multiple product deaths that involved an EDT) 

involved generators.

Heating Systems:

• Of the estimated 40 Heating Systems-related fatalities in 2009, 85 percent (34 deaths)

involved gas heating equipment. Natural gas heating equipment accounted for 33 percent 

(13 deaths) of all fuel types of heating system-related fatalities; liquefied petroleum (LP 

or propane) gas heating accounted for 48 percent (19 deaths); and an additional 5 percent 

(2 deaths) were only identified as unspecified gas heating. Oil- (3 deaths) and woodfueled (2 deaths) heating systems accounted for a total of 13 percent. Three additional 

fatalities (8 percent) were associated with heating systems, where the fuel type could not 

be ascertained from CPSC records.

 1 Not all of these fatalities are addressable by an action the CPSC could take; however, it was not the purpose of this 

report to evaluate the addressability of the incidents but rather to update the estimates of the number of consumer 

products associated with CO poisoning deaths. 2 Numbers presented in this document represent national estimates of unintentional non-fire deaths attributed to CO 

poisoning that were associated with the use of consumer products and not observed counts as presented in the CPSC 

report Incidents, Deaths, and In-Depth Investigations Associated with Non-Fire Carbon Monoxide from EngineDriven Generators and Other Engine-Driven Tools, 1999–2011.

http://www.cpsc.gov/library/foia/foia12/os/cogenerators.pdf.
4 | Page

Location/Demographics:

• CPSC staff is aware of 115 fatal non-fire CO incidents involving consumer products in 

2009. Seventy-nine percent (91 deaths) of these incidents involved a single fatality.

• Seventy-nine percent (116 deaths) of the estimated 146 CO deaths in 2009 occurred in a

home location. Of these 116 estimated fatalities, 7 occurred in an external structure, such 

as a shed or detached garage, and 1 occurred in a nonfixed location domicile (e.g., 

camper trailer, boat) used as a permanent home, or a structure not designed for habitation 

(e.g., sea-land shipping container, metal shed). Additionally, an estimated 12 percent (18

deaths) occurred in tents, camper trailers, and other temporary shelters. 

• More CO fatalities occurred in the colder months of the year. In 2009, 58 percent (84 of 

146 deaths) occurred during the colder months of November, December, January, and 

February.

• In the three most recent years of this report (2007–2009), adults 45 years and older 

comprised an annual average of 59 percent of all non-fire, consumer product-related CO 

deaths, while this age group makes up about 39 percent of the U.S. population. 

Conversely, children less than 15 years of age accounted for an annual average of 5 

percent of the yearly CO poisoning deaths, while this age group makes up about 20 

percent of the U.S. population. 

• In 2009, 73 percent (an estimated 107 deaths) of CO poisoning victims were males, and 

27 percent (39 deaths) were females. 

• There is some statistical evidence that the proportion of fatalities by race/ethnicity differs 

from the proportions of race/ethnicity in the U.S. population in the 2007 through 2009 

time frame. The proportion of Hispanic victims (irrespective of race) is significantly 

lower than the proportion of Hispanic Americans in the U.S. population (9% versus 15%) 

while the proportion of Black or African American victims was marginally significantly 

greater of the U.S. population (17% versus 12%) during this time period. 

• The proportion of all CO poisoning fatalities that occurred in small towns or isolated 

rural locations (20 percent in 2007 through 2009) is larger than the proportion of the U.S. 

population living in these areas (9 percent). The disparity is even higher at isolated nonhome locations, which account for 29 percent of all CO fatalities occurring at non-home 

locations.
5 | Page

Historical Data:

• Regression models indicate that there is a statistically significant increasing trend in nonfire CO fatalities from 1999 to 2009, although the short-term trend since 2005 appears to 

have leveled off, or perhaps, has even been declining. 

• The CO poisoning 3-year average mortality rate for 2007 through 2009 associated with

consumer products (5.56 per 10 million population) is approximately 28 percent greater 

than the 3-year average for 2000 (expressed as the midpoint year of the 3-year period 

1999 to 2001) of 4.34 per 10 million population. However, for non-engine-driven tool 

products, the mortality rate has decreased by 20 percent from 3.62 (the 2000 3-year 

average) down to a 2.91 average mortality rate in 2008 (the average rate for 2007 through 

2009). Conversely, the mortality rate of CO poisoning from engine-driven tools during 

the same time period more than tripled, increasing from 0.72 in 2000, up to a 3-year 

average of 2.65 for 2008. Details are given in Appendix B of this report. 
6 | Page

Introduction

Carbon monoxide (CO) is a colorless, odorless, and poisonous gas that results from the 

incomplete combustion of fuels, such as natural or liquefied petroleum (LP) gas, gasoline, oil, 

wood, coal, and other fuels. The health effects related to CO depend upon its concentration in 

blood, which in turn, depends upon its concentration in air, the duration of exposure, and an 

individual’s general health. Carbon monoxide combines with the body’s hemoglobin (Hb) with 

an affinity about 250 times that of oxygen, forming carboxyhemoglobin (COHb) and interfering 

with oxygen transport, delivery, and utilization. Generally, there are no perceptible health 

effects or symptoms in healthy individuals at COHb levels below 10 percent. Symptoms 

associated with blood levels at or above 10 percent COHb include: headache, fatigue, nausea, 

and cognitive impairment. Loss of consciousness, coma, and death can occur at COHb levels 

greater than 20 percent; although for healthy adults, CO fatalities typically require levels above 

50 percent COHb.

3

Some symptoms of CO poisoning may mimic common illnesses, such as influenza or 

colds; thus, there likely is a high incidence of initial misdiagnosis by physicians and victims 

(Long and Saltzman, 1995). Frequently, patients are unaware of exposures, and health care 

providers may not always consider CO poisoning a cause of such nonspecific symptoms. COHb 

formation is reversible, as are some clinical symptoms of CO poisoning. However, some 

delayed neurological effects that develop following severe poisonings, especially those involving 

prolonged unconsciousness, may not be reversible. Prompt medical attention is important to 

reduce the risk of permanent damage.

Any fuel-burning appliance can be a potential source of fatal or hazardous CO levels. 

Fuels, such as natural and LP gas, kerosene, oil, coal, and wood can produce large amounts of 

CO when there is insufficient oxygen available for combustion. Consumer products that burn 

kerosene, oil, coal, or wood (such as wood stoves, oil boilers, and kerosene heaters) produce an 

irritating smoke that can alert the victim to a potentially hazardous situation. Engine-driven tools 

powered by gasoline engines produce large amounts of CO, even when they are run where there 

is sufficient oxygen available for combustion, yet they may not emit an irritating exhaust smoke. 

Other fuels, such as charcoal briquettes and pressed wood-chip logs produce relatively smokeless 

fires, even at times of inefficient combustion. In these cases, victims receive no obvious sensory 

warning that high CO levels are present. Another hazard scenario is present when gas appliances 

are not vented properly or are malfunctioning. Natural and LP gas burn more efficiently and 

cleanly, compared with other forms of fuel. In circumstances of poor maintenance, inadequate 

ventilation, or faulty exhaust pathways, natural and LP gas appliances may emit potentially lethal 

amounts of CO without any irritating fumes. Again, many victims may be unaware of a potential 

problem.

 3 Inkster S.E. Health hazard assessment of CO poisoning associated with emissions from a portable, 5.5 kilowatt, 

gasoline-powered generator. Washington, D.C.: U.S. Consumer Product Safety Commission, 2004.
7 | Page

National Estimates of Non-Fire CO Poisoning Deaths Associated with Consumer Products

During 2009, there were an estimated 146 carbon monoxide (CO) poisoning deaths 

associated with the use of a consumer product under the jurisdiction of the U.S. Consumer 

Product Safety Commission (CPSC). The estimates presented in this report are based on nearly 

complete reporting of consumer product-related CO poisoning fatalities that occurred in 2009. 

The National Center for Health Statistics (NCHS) has records of every death certificate filed in 

the United States and its territories. A comparison of CPSC records to NCHS records indicates 

that CPSC records have data on nearly 97 percent of all the fatal CO poisoning deaths that 

occurred in 2009, in the United States. For the 10 years covered in this report prior to 2009, 

CPSC records contain approximately 91 percent of all the fatal CO poisoning deaths that

occurred in the United States reported to NCHS. Carbon monoxide poisoning deaths referred to 

in this report do not include those where the CO gas resulted from a fire or a motor vehicle, were 

intentional in nature, or were directly work-related.

Although there can be multiple factors contributing to a CO poisoning fatality, the source 

of CO is virtually always a fuel-burning product. As mentioned earlier, poor product 

maintenance by professionals or consumers, inadequate ventilation, faulty exhaust pathways, and 

poor user judgment in operating these products can result in fatal scenarios. It should be noted 

that CPSC staff produces the CO estimates by associated consumer products in order to identify 

product groups involved in fatal CO scenarios and to monitor this distribution over time. It is 

within the individual, product-specific CPSC projects that further analysis is done to consider 

whether improvements are warranted in the areas of product design, ventilation safeguards, or 

user information and education.

The annual CO estimates for the years 1999 through 2009 are presented in two formats: 

by product type (Table 1) and by product within fuel type (Table 2). The data are presented as 

yearly estimates for each of the 11 years covered by this report and as an average of the most 

recent 3-year period (2007 through 2009). At the time this report was prepared, data collection 

was nearly complete for 2009. Estimates for this year may change in the future, if additional 

data become available. Therefore, they are reported using italic font in the tables. 

It should be noted that numbers presented in this document represent national estimates of 

unintentional non-fire deaths attributed to CO poisoning that were associated with the use of 

consumer products. Generator and other EDT death estimates would not be expected to match 

observed fatality counts presented in the CPSC report, “Incidents, Deaths, and In-Depth 

Investigations Associated with Non-Fire Carbon Monoxide from Engine-Driven Generators and 

Other Engine-Driven Tools, 1999–2011.” 

Table 1 (pages 10−11) presents the consumer product distribution of CO poisoning 

deaths. The estimate for Heating Systems, historically a large percentage of the consumer 

product estimate, is broken down into heater system subcategories and is further distributed 

among the various fuel types. Fatality estimates for the Engine-Driven Tools category were

further distributed between generators and other engine-driven tools. The consumer product 

estimate and product distributions were derived using the methodology described in Appendix A. 
8 | Page

Of the estimated 146 CO poisoning deaths associated with a consumer product that 

occurred between January 2009 and December 2009, Heating Systems were associated with 40

deaths (27% of the total consumer product estimate). Of the 40 deaths associated with heating 

systems, the majority (85% or 34 fatalities) involved gas heating systems. Among gas heating 

systems, natural gas heating was associated with an estimated 13 deaths (33% of heating systemrelated deaths). Liquid Petroleum gas (LP gas)4 heating was associated with an estimated 19

deaths (48% of heating system-related deaths); and unspecified gas heating was associated with 

an estimated two deaths (5% of heating system-related deaths). Oil-fueled heating was

associated with an estimated three deaths (8% of heating system-related deaths). There were an 

estimated two deaths (5% of heating system-related deaths) associated with a wood-burning 

heater. There are no reported kerosene-, coal-, or diesel-fueled heating system fatalities in the 

2009 data. Additionally, in 2009, there was an estimated one CO death (3% of heating systemrelated deaths) associated with heating systems with unknown fuel sources. Note that the 

estimates for individual categories may not sum to that of the broader category due to rounding 

effects.

Of the estimated 13 deaths in 2009 that were associated with natural gas heating systems, 

11 (85%) involved installed furnaces—one (8%) of which was described as being a wall or floor 

furnace. In addition to the 11 furnace-related deaths, two deaths (15%) were described as being 

associated with natural gas-fueled room or space heaters. Of the estimated 19 deaths in 2009

that were associated with LP gas heating systems, eight (42%) involved unvented portable 

propane heaters. These unvented portable propane heaters were fueled by a propane tank and 

were not a component of an installed heating system. Unvented portable propane heaters were 

either camping heaters that used disposable propane tanks, one-pound propane bottles, or tank 

top heaters that used bulk tanks larger than one pound. 

In 2009, an estimated seven CO deaths (5% of the 146 total consumer product estimate) 

were associated with charcoal or charcoal grills; an estimated five deaths (3%) were associated 

with water heaters; an estimated 3 deaths (2%) were associated with gas ranges or ovens; an 

estimated one death (1%) was associated with LP-fueled lanterns; and an estimated 2 deaths 

were associated with other gas-fueled products. Additionally, in 2009, an estimated 11 deaths 

were associated with multiple appliances (8% of the total consumer product estimate). The 

Multiple Products category includes all incidents where multiple fuel-burning products were 

used simultaneously, such that a single source of the CO could not be determined. 

An estimated 78 CO poisoning deaths (53% of the estimated total for 2009) were 

associated with the category of Engine-Driven Tools, which includes generators, riding mowers 

or garden tractors, snow blowers/throwers, and other engine-driven equipment. Additionally, 2

of the 11 Multiple Product fatalities were associated with some type of engine-driven tool being 

used in conjunction with another fuel-burning product for an estimated total of 80 CO fatalities 

associated with the use of an engine-driven tool (55% of the estimated total for 2009). Generator 

associated deaths comprise the majority of this category. An estimated 67 CO poisoning deaths 

were associated with a generator, including both of the Multiple Product fatalities involving an 

engine-driven tool in 2009 (84% of all engine-driven tool fatalities and nearly half of the total 

consumer product estimate). 

 4 In this document, references to liquid petroleum gas, or LP gas, also include propane and butane gases, the two 

primary components of LP gas.
9 | Page

In recent years, the Engine-Driven Tools category has been associated with more CO 

fatalities than any other category. The estimated number of CO fatalities associated with enginedriven tools (78, not including multiple product incidents) in 2009, is greater than the number 

associated with heating systems (40 deaths). Since 2005, there have been a far greater number of 

CO fatalities associated with engine-driven tools than with heating systems. There have been an 

estimated combined total of 448 engine-driven tool-related CO fatalities from 2005 through

2009, compared to 260 deaths combined for heating systems. From 1999 through 2004, there 

were twice as many heating system-related CO fatalities (448) than engine-driven tool-related 

fatalities (224). (Note: These figures exclude fatalities associated with multiple products because

these possibly could be categorized into both categories.) Stated differently, while heating 

system-related CO fatalities have dropped by 30 percent from an approximate estimated average 

of 75 per year from 1999 through 2004, to an average of 52 per year from 2005 through 2009, 

the estimated annual average number of engine-driven, tool-related CO fatalities have increased 

by 140 percent over the same time period, from 37 to 90.

Table 1 (pages 10−11) shows the estimated average annual number of CO poisoning 

deaths associated with a consumer product for 2007 to 2009. The average yearly total number of 

CO deaths for this 3-year period is estimated to be 169 (with a standard error of approximately 

12.0). The 95 percent confidence interval5 for this estimated average ranged from 118 to 221

deaths. Appendix B contains a graph and the data point values for the annual estimates of CO 

poisoning deaths associated with a consumer product for 1980 through 2009.

Detailed information regarding the condition of products associated with fatalities was

not reliably collected, and the availability of such information in the CPSC’s files varied widely. 

However, information collected often described conditions regarding compromised vent systems, 

flue passageways, and chimneys for furnaces, boilers, and other heating systems. Vent systems 

include the portion of piping that connects the flue outlet of the appliance and exhausts air to the 

outside through a ceiling or sidewall, or connects to a chimney. Some vented products had vents 

that became detached or were installed or maintained improperly. Vents were also sometimes 

blocked by soot caused by inefficient combustion, which, in turn, may have been caused by 

several factors, such as leaky or clogged burners, an over-firing condition, or inadequate 

combustion air.

Other conditions related to furnaces included compromised heat exchangers or filter 

doors or covers that were removed or not sealed. Some products were old and apparently poorly 

maintained, such that there were several factors involved in generating and exacerbating the 

amount of CO produced. Other incidents mentioned a backdraft condition, large amounts of 

debris in the chimney, and the use of a product that was later red-tagged by the utility company 

(taken out of commission by the utility company and designated not to be turned on until 

repaired). 

 5 The confidence interval is based on a t-distribution with two degrees of freedom.
10 | Page

Table 1: Estimated Non-Fire Carbon Monoxide Poisoning Deaths by Associated Fuel-Burning Consumer Product, 1999–2009

2007–2009+ Annual Estimates

Consumer Product Average 

Estimate

Average 

Percent 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009+

Total 169 100% 108 138 121 181 153 168 190 180 186 176 146

Heating Systems 55 33% 50 82 71 93 67 85 47 49 66 58 40

 Furnaces 25 15% 22 37 26 47 29 43 14 30 29 30 16

 Coal * * * 1 1 1 * 1 * * * * *

 Liquid Petroleum (LP) Gas 1 1% 5 7 7 16 3 8 1 9 * 3 1

 Natural Gas 16 9% 15 25 10 21 19 23 6 19 20 19 10

 Oil 3 2% * 4 3 3 1 * 2 * 5 1 3

 Unspecified Gas 2 1% 1 * 1 1 2 4 2 * 4 2 1

 Unspecified Fuel 2 1% 1 * 3 4 4 8 3 2 * 5 1

 Portable Heaters 13 8% 16 20 17 26 25 20 23 14 17 13 8

 Diesel * * * * * 1 * * * * * * *

 Kerosene 2 1% 3 3 1 4 5 4 2 3 3 4 *

 Liquid Petroleum (LP) Gas 10 6% 12 14 16 20 18 15 19 10 14 9 8

 Natural Gas * * 1 2 * * 2 * * * * * *

 Unspecified Gas * * * * * * * 1 1 * * * *

 Unspecified Fuel * * * * * * * * 1 1 * * *

 Wall/Floor Furnaces 6 4% 6 15 18 9 4 6 2 2 9 3 6

 Liquid Petroleum (LP) Gas 3 2% 3 5 2 4 1 5 * * 4 1 5

 Natural Gas 3 2% 2 10 13 4 3 1 2 2 5 2 1

 Oil * * * * 1 * * * * * * * *

 Unspecified Fuel * * * * 2 * * * * * * * *

 Room/Space Heaters 7 4% 6 9 9 10 8 12 4 1 6 5 9

 Coal * * * * 3 * * 1 1 * * * *

 Liquid Petroleum (LP) Gas 4 2% 3 1 1 * 1 * * * 4 2 5

 Natural Gas 1 1% 1 7 3 5 3 6 * 1 * 2 2

 Wood 1 1% * 1 1 1 2 * 2 * * 1 2

 Unspecified Gas 1 1% 1 * * 3 2 4 1 * 2 * *

 Unspecified Fuel * * * 1 * * * * 3 * * * *

 Unspecified Heater/System 4 2% * 1 * 2 * 3 3 1 5 7 1

 Liquid Petroleum (LP) Gas 1 1% * 1 * * * * * * 1 2 *

 Natural Gas 1 1% * * * * * * * * 3 * *

 Unspecified Gas 1 1% * * * 1 * 2 * * * 1 1

 Unspecified Fuel 2 1% * * * 1 * 1 3 1 1 4 *
11 | Page

Table 1 (continued)

2007–2009+ Annual Estimates

Consumer Product Average 

Estimate

Average 

Percent 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009+

Engine-Driven Tools 81 48% 13 26 21 52 56 56 102 104 79 85 77

 Generators 70 41% 7 19 20 42 49 41 88 85 68 77 65

 Other Engine-Driven Tools 11 7% 6 8 1 10 7 15 13 18 11 8 13

Charcoal Grills, Charcoal 8 5% 17 8 10 11 8 3 6 10 8 8 7

Gas Ranges or Ovens 3 1% 6 12 9 3 3 4 6 * 6 * 3

 Liquid Petroleum (LP) Gas < 1 < 1% 3 1 2 * * 1 1 * 1 * *

 Natural Gas 1 1% 2 5 1 3 * 2 1 * 2 * 1

 Unspecified Gas 2 1% * 5 6 * 3 1 3 * 3 * 2

Gas Water Heaters 4 2% 1 3 * 1 7 2 6 4 2 6 5

 Liquid Petroleum (LP) Gas 1 1% * * * * 3 1 2 * 1 1 2

 Natural Gas 1 1% * 2 * 1 3 * * 3 * 1 1

 Oil < 1 < 1% * * * * * * * * * 1 *

 Unspecified Gas 1 1% 1 1 * * 1 1 3 1 1 1 1

 Unspecified Fuel 1 1% * * * * * * * * * 2 1

Lanterns - Liquid Petroleum (LP) 

Gas Fueled 2 1% 8 3 * 2 1 3 6 3 * 4 1

Grills, Camp Stoves 1 1% 5 1 1 4 1 4 * 2 2 * *

 Kerosene * * * * * * * 1 * * * * *

 Liquid Petroleum (LP) Gas < 1 < 1% 5 1 1 4 1 3 * 1 1 * *

 Unspecified Fuel < 1 < 1% * * * * * * * 1 1 * *

Other Products 2 1% 2 * * 2 2 3 3 * 2 2 2

 Chimney – Unspecified Fuel * * * * * * * * 1 * * * *

 Fireplace – Unspecified Gas < 1 < 1% * * * * * * * * 1 * *

 Fireplace – Wood < 1 < 1% * * * 2 * 2 * * 1 * *

 Other Products –

 Liquid Petroleum (LP) Gas < 1 < 1% 1 * * * 2 * 1 * * * 1

 Other Products – Natural Gas < 1 < 1% 1 * * * * * 1 * * * 1

 Unidentified Product * * * * * * * 1 * * * * *

 Unidentified Product – LP Gas 1 1% * * * * * * * * * 2 *

Multiple Products 14 8% 6 2 8 13 8 7 12 8 20 11 11

+ Data collection for 2009 is nearly complete. Italicized estimates may change in the future if more reports of fatalities are received.

* No reports received by CPSC staff.

Source: U.S. Consumer Product Safety Commission/EPHA.

 CPSC Death Certificate File, CPSC Injury or Potential Injury Incident File, CPSC In-Depth Investigation File,

 National Center for Health Statistics Mortality File, 1999–2009.

Note: Reported annual estimates and estimated averages and percentages may not add to subtotals or totals due to rounding.
12 | Page

Table 2 (beginning on page 13) organizes the estimates by product within fuel type. The 

three major fuel types include: Gas-Fueled Products (natural gas and liquid petroleum [LP

including propane and butane] gas); Solid-Fueled Products (charcoal, coal, and wood); and 

Liquid-Fueled Products (gasoline, kerosene, and oil). Of these fuel types, Liquid-Fueled 

Products were associated with 81 of the 146 (55%) estimated CO fatalities in 2009. Gas-Fueled 

Products and Solid-Fueled Products were associated with 52 (36%) and 9 (6%) estimated 

fatalities in the same time period, respectively. An additional two (1%) fatalities were associated 

with multiple products, where there were two or more different categories of fuel used. 

Multiproduct cases, where the fuel types were the same, are counted in their respective category 

summary. There were also two (1%) fatalities in 2009 associated with consumer products where 

the fuel type was unknown.

In the Gas-Fueled Products category, the majority of CO fatalities in 2009 were 

associated with heating-related products. Of the estimated 52 gas-fueled appliance fatalities in 

2009, 34 (65%) were associated with heating systems or heaters, including furnaces and boilers, 

portable heaters, wall or floor heaters, room or space heaters, or fireplaces. Additionally, five of 

the estimated eight fatalities in the Multiple Gas-Fueled Products category involved some type 

of gas heater. Of the estimated 81 liquid-fueled appliance-related fatalities in 2009, 77 (95%) 

were associated with engine-driven tools (e.g., generators, lawn mowers/garden tractors, power 

washers). Generators accounted for 65 of the estimated 81 fatalities (80%) in the Liquid- Fueled 

Products category for 2009. Additionally, the estimated one fatality in the Multiple LiquidFueled Products category also involved a generator. 

In 2009, there were an estimated nine fatalities in the Solid-Fueled Products category. 

Seven of these were associated with charcoal or charcoal grills and two with a wood-burning 

room heater. Additionally, there were an estimated two CO fatalities associated with multiple 

products of different fuel types— both involved portable LP heaters (gas-fueled), one involved a 

generator (liquid-fueled), and one involved charcoal (solid-fueled). 
13 | Page

Table 2: Estimated Non-Fire Carbon Monoxide Poisoning Deaths Associated with Consumer Products Organized by Fuel Type, 1999–2009

2007–2009+ Annual Estimates

Consumer Product Average 

Estimate

Average 

Percent 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009+

Total 169 100% 108 138 121 181 153 168 190 180 186 176 146

Gas-Fueled Products 62 37% 72 93 66 92 70 87 53 51 80 55 52

 Natural Gas 25 15% 23 51 28 35 30 32 10 26 30 28 16

 Furnace 16 9% 15 25 10 21 19 23 6 19 20 19 10

 Pool Heater * * 1 * * * * * 1 * * * *

 Portable Heater * * 1 2 * * 2 * * * * * *

 Range/Oven 1 1% 2 5 1 3 * 2 1 * 2 * 1

 Room/Space Heater 2 1% 1 7 3 5 3 6 0 1 * 3 2

 Wall/Floor Furnace 3 2% 2 10 13 4 3 1 2 2 5 3 1

 Water Heater 1 1% 0 2 0 1 3 * * 3 * 1 1

 Unspecified Heater 1 1% * * * * * * * * 3 * *

 Other Appliance < 1 < 1% * * * * * * * * * * 1

 Liquid Petroleum (LP) Gas 27 16% 40 34 30 47 31 37 30 23 26 31 23

 Furnace 1 1% 5 7 7 16 3 8 1 9 * 3 1

 Grill/Camp Stove < 1 < 1% 5 1 1 4 1 2 * 1 1 * *

 Lantern 2 1% 8 3 * 2 1 4 6 3 * 4 1

 Other Products 1 1% * * * * 1 * * * * 3 1

 Portable Heater 10 6% 12 14 16 20 18 15 19 10 14 9 8

 Range/Oven < 1 < 1% 3 1 2 * * 1 1 * 1 * *

 Refrigerator * * 1 * * * 1 * 1 * * * *

 Room/Space Heater 4 2% 3 1 1 * 1 * * * 4 3 5

 Unspecified Heater/System 1 1% * 1 * * * * * * 1 3 *

 Wall/Floor Furnace 3 2% 3 5 2 4 1 5 * * 4 1 5

 Water Heater 1 1% * * * * 3 1 2 * 1 1 2

 Unspecified Gas 6 4% 3 7 7 5 8 15 11 1 11 3 5

 Furnace 2 1% 1 * 1 1 2 5 2 * 4 2 1

 Portable Heater * * * * * * * 1 1 * * * *

 Range/Oven 2 1% * 5 6 * 3 1 3 * 3 * 2

 Room/Space Heater 1 1% 1 * * 3 2 4 1 * 2 * *

 Fireplace < 1 < 1% * * * * * * * * 1 * *

 Water Heater 1 1% 1 1 * * 1 1 3 1 1 1 1

 Unspecified Heater 1 1% * * * 1 * 2 * * * 1 1

 Multiple Gas-Fueled Products 8 5% 5 1 2 4 1 3 2 1 13 2 8
14 | Page

Table 2 (continued)

2007–2009+ Annual Estimates

Consumer Product Average 

Estimate

Average 

Percent 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009+

Liquid-Fueled Products 88 52% 16 35 28 64 66 61 108 108 89 95 81

 Gasoline-Fueled 80 47% 13 26 21 52 56 56 102 104 78 85 77

 Generator 70 41% 7 19 20 42 49 41 88 85 68 77 65

 Other Engine-Driven Tools 11 7% 6 8 1 10 7 15 13 18 11 8 13

 Kerosene-Fueled 2 1% 3 3 1 4 5 5 2 3 3 4 *

 Grill/Camp Stove * * * * * * * 1 * * * * *

 Portable Heater 2 1% 3 3 1 4 5 4 2 3 3 4 *

 Oil-Fueled 3 2% * 4 5 3 1 * 2 * 5 2 3

 Furnace 3 2% * 4 3 3 1 * 2 * 5 1 3

 Water Heater < 1 < 1% * * * * * * * * * 1 *

 Wall/Floor Furnace * * * * 1 * * * * * * * *

 Diesel-Fueled * * * * * 1 * * * * * * *

 Portable Heater * * * * * 1 * * * * * * *

 Multiple Liquid-Fueled 

Products 2 1% * 1 1 4 4 * 2 1 2 4 1

Solid-Fueled Products 9 5% 17 10 16 15 10 8 9 10 9 9 9

 Charcoal-Fueled 8 5% 17 8 10 11 8 3 6 10 8 8 7

 Charcoal / Charcoal Grills 8 5% 17 8 10 11 8 3 6 10 8 8 7

 Coal-Fueled * * * 1 5 1 * 2 1 * * * *

 Furnace * * * 1 1 1 * 1 * * * * *

 Room/Space Heater * * * * 3 * * 1 1 * * * *

 Wood-Fueled 1 1% * 1 1 3 2 2 2 * 1 1 2

 Chimney/Fireplace < 1 < 1% * * * 2 * 2 * * 1 * *

 Room/Space Heater 1 1% * 1 1 1 2 * 2 * * 1 2
15 | Page

Table 2 (continued)

2007–2009+ Annual Estimates

Consumer Product Average 

Estimate

Average 

Percent 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009+

Unspecified Fuel Products 5 3% 1 1 6 5 4 9 12 6 2 11 2

 Chimney * * * * * * * * 1 * * * *

 Furnace 2 1% 1 * 3 4 4 6 3 2 * 5 1

 Grill/Camp Stove < 1 < 1% * * * * * * * 1 1 * *

 Portable Heater * * * * * * * * 1 1 * * *

 Room/Space Heater * * * 1 * * * * 3 * * * *

 Unspecified Heater 2 1% * * * 1 * 1 3 1 1 4 *

 Wall/Floor Furnace * * * * 2 * * * * * * * *

 Unidentified Product * * * * * * * 1 * * * * *

 Water Heater 1 1% * * * * * * * * * 2 1

Multiple Product - Different 

Fuels 4 2% 1 * 5 4 4 2 8 6 5 5 2

 Gas & Liquid 3 2% 1 * 5 4 3 2 7 6 5 3 1

 Gas & Solid < 1 < 1% * * * * * * 1 * * * 1

 Liquid & Solid < 1 < 1% * * * * 1 * * * * 1 *

 Gas & Liquid & Unspecified 1 1% * * * * * * * * * 2 *

+ Data collection for 2009 is nearly complete. Italicized estimates may change in the future if more reports of fatalities are received.

* No reports received by CPSC staff.

Source: U.S. Consumer Product Safety Commission/EPHA.

 CPSC Death Certificate File, CPSC Injury or Potential Injury Incident File, CPSC In-Depth Investigation File,

 National Center for Health Statistics Mortality File, 1999–2009.

Note: Reported annual estimates and estimated averages and percentages may not add to subtotals or totals due to rounding.
16 | Page

Table 3 (below) shows a breakdown of the fatality estimates for the 11-year period from 

1999 through 2009 in the Engine-Driven Tools category. During 2009, engine-driven tools were 

associated with an estimated 79 carbon monoxide poisoning deaths (54% of the total consumer 

product estimate). Table 3 totals differ from those in Tables 1 and 2 in that they also include 

fatalities associated with multiple potential CO-producing products, where at least one product 

was an engine-driven tool. In 2009, there were two such deaths—both associated with a 

generator and some other product (in both cases, some type of heater). An estimated 67 of the 79

engine-driven tool-related CO poisoning deaths (85%) were associated with generators, or 

generators in conjunction with another fuel-burning product. In 2009, the other engine-driven,

tool-related CO fatalities included an estimated six deaths that were associated with riding lawn 

mowers, three with snow blowers, and four were associated with other types of engine-driven 

products. 

Table 3: Estimated Non-Fire Carbon Monoxide Poisoning Deaths Associated with 

Engine-Driven Tools, 1999–2009

Engine-Driven Tools

2007-2009+

Average 

Estimate

Average 

Percentage

Annual Estimate

1999 2000 2001 2002 2003 2004 2005 2006 2007 2008+ 2009+

Total 86 100% 14 27 27 58 63 59 110 107 85 93 79

Generators 70 81% 7 19 20 41 50 41 88 85 68 77 65

Other Engine-Driven 

Tools (OEDTs) 10 12% 6 8 1 10 7 15 13 18 11 6 13

 Lawn Mowers 4 5% 6 7 1 5 6 8 9 11 5 2 6

 Riding Mowers 4 5% 6 5 1 5 6 5 9 8 4 2 6

 Walk Behind Mowers * * * 1 * * * 1 * * * * *

 Unspecified Mowers < 1 < 1% * * * * * 1 * 3 1 * *

 Power Washer 1 1% * * * * * 2 3 1 1 * 1

 Snow Blower / Thrower 2 2% * 1 * * * 1 * 1 2 * 3

 ATV 1 1% * * * 1 * 1 1 * * 2 *

 Water Pump < 1 < 1% * * * * * 1 * 1 1 * *

 Welder 1 1% * * * 2 1 * * * 1 1 *

 Air Compressor * * * * * * * 1 * 1 * * *

 Concrete Saw < 1 < 1% * * * 1 * 1 * * * 1 *

 Tiller < 1 < 1% * * * * * * * * * * 1

 Go-Cart 1 1% * * * * * * * * * * 2

 Small Engine * * * * * * * * * 1 * * *

 Snowmobile * * * * * * * * * 1 * * *

Multiple Product: EngineDriven Tools Involved 6 7% 1 1 6 8 6 3 9 3 6 9 2

 Generator + OEDT * * * * 1 * * * * * * * *

 Generator + other

 Product 5 6% * 1 5 6 5 2 9 3 6 8 2

 Multiple OEDT < 1 < 1% * * * * * * * * * 1 *

 OEDT + other product * * 1 * * 1 1 1 * * * * *

+ Data collection for 2009 is nearly complete. Italicized estimates may change in the future if more reports of fatalities are received.

* No reports received by CPSC staff.

Source: U.S. Consumer Product Safety Commission/EPHA.

 CPSC Death Certificate File, CPSC Injury or Potential Injury Incident File, CPSC In-Depth Investigation File,

 National Center for Health Statistics Mortality File, 1999–2009.

Note: Reported annual estimates and estimated averages and percentages may not add to subtotals or totals due to rounding.
17 | Page

In 2009, there were an estimated 77 CO fatalities associated with engine-driven tools (79,

if the two multiproduct incidents involving an engine-driven tool are included). As can be seen 

in Table 3, the estimated numbers of fatalities associated with engine-driven tools increased 

dramatically in 2005 and 2006, over previous years. The large increase in the number of enginedriven tool fatalities in 2005 can partially be explained by the large increase of generator-related 

deaths associated with severe weather events. An unusually severe hurricane season and ice 

storms in the South and the Midwest caused widespread power outages, prompting consumers to 

resort to the use of generators, often unsafely, as an alternative source of power. It is unclear 

why the number of generator fatalities remained high in 2006, which was a relatively mild 

weather event year. From 2007 through 2009, there were an estimated average of 86 CO 

fatalities associated with engine-driven tools, slightly lower than the peak 2005/2006 levels (an 

estimated of 109), but still in excess of the pre-2005/2006 levels. 

Figure 1 provides a graphic representation of the CO fatality trends related to: (1) all 

consumer products; (2) to engine-driven tools alone, and (3) to non-engine-driven tools. A 

regression analysis of the estimated number of all non-fire, consumer product-related CO 

poisoning fatalities from 1999 to 2009, indicates that there is statistical evidence of an upward 

trend in the data (p-value = 0.0376), even though the short-term trend since 2005 appears to have 

leveled off, or perhaps, has even been declining. It should be pointed out that due to reporting 

delays, national estimates for recent years, especially 2009, most likely will change in 

subsequent reports. As can be seen in the figure, the estimated number of non-generator CO 

fatalities fluctuates from year-to-year, but appears to be fairly steady though in 2009, when there 

were fewer non-generator CO fatalities than any other year of this report. Conversely, the 

estimated number of generator CO fatalities has shown a steady rise, to peak levels in 2005 and 

2006. The estimated number of generator CO fatalities in 2007 through 2009 are below the peak 

2005 and 2006 levels, but greater than the years prior to 2005.
18 | Page

Figure 1: Comparison of Trends in Consumer Product-Related Carbon 

Monoxide Deaths – 1999 to 2009

Lawnmowers were associated with 61 percent (66 of 108) of the deaths in the Other 

Engine-Driven Tools category for the 11-year period. There were two other fatalities associated 

with a lawnmower and another product in this time period—one with a generator, and the other 

with a propane heater. There was an estimated average of four lawnmower-related CO fatalities 

per year in 2007 to 2009 (13 deaths). CO fatalities related to snow blower/thrower usage were in

the next largest subcategory, with an estimated eight deaths from 1999 to 2009, and five 

occurred from 2007 through 2009.

Table 4 shows that in 2009, 79 percent of fatal CO incidents reported to the CPSC 

involved a single death. Table 4 accounts for only the fatally injured victims in each CO 

poisoning incident. It is not uncommon for CO incidents involving one or more fatalities also to 

result in one or more nonfatal CO poisoning injuries, but they were not quantified for analysis in 

this report. It should be noted that these are the incidents reported in CPSC databases and do not 

represent the national estimates of fatalities per CO incident. Death certificates do not include 

information about other fatalities for the same incident. The number of fatalities for a particular 

incident are based on CPSC In-Depth Investigation files and may include fatalities for which 

0

20

40

60

80

100

120

140

160

180

200

1998 2000 2002 2004 2006 2008 2010

generator non-generator All products
19 | Page

CPSC staff does not have death certificates. Some additional multiple fatality incidents were 

identified by matching date of death, and location of death on death certificates, while others 

were identified from news articles contained in the CPSC Injury or Potential Injury Incident 

(IPII) database. Over the 11-year period covered by this report, CPSC records indicate that 19 

percent (247 of 1,304 incidents) resulted in multiple fatalities, including 15 incidents resulting in 

four or more CO fatalities.

Table 4: Number of Carbon Monoxide Poisoning Incidents Reported to CPSC by 

Number of Deaths Per Incident, 1999–2009

Number of 

Deaths Reported 

in Incident

2007−2009+ Annual Incidents

Annual 

Average

Average 

Percent 1999 2000 2001 2002 2003 2004 2005# 2006 2007 2008 2009+

Total Incidents 133 100% 78 104 88 130 121 127 146 123 147 139 115

1 109 82% 63 82 71 101 96 105 123 93 125 118 91

2 16 12% 14 19 15 24 21 14 17 22 13 15 19

3 6 5% * 2 2 1 3 7 5 6 8 4 4

4 1 1% 1 * * 2 * 1 * 1 1 2 1

5 < 1 < 1% * * * 2 1 * * 1 * * *

6 * * * 1 * * * * 1 * * * *

+ Data collection for 2009 is nearly complete. Italicized estimates may change in the future if more reports of fatalities are received.

* No incident reports received by CPSC staff were for this time period.

# 2005 data include one case where there were two CO fatalities, but only one was considered in scope for this report due to the work-related nature of the 

 incident (one worker, one non-worker). This incident is identified in this table as a two-death incident, but only the non-work-related fatality is accounted for 

 elsewhere in the report.

Source: U.S. Consumer Product Safety Commission/EPHA.

 CPSC Death Certificate File, CPSC In-Depth Investigation File, CPSC Injury or Potential Injury Incident File, 1999–2009.

Note 1: Data in Table 4 do not add to totals presented in Table 1. Data presented in Table 4 are not national estimates derived from NCHS totals, but

 reported deaths contained in the CPSC files. NCHS data do not contain enough detail to identify multiple victims of the same CO poisoning

 incident. These figures include fatalities reported in CPSC In-Depth Investigation files for which CPSC may not have a death certificate.

Table 5 shows that in 2009, an estimated 116 CO poisoning deaths occurred in home 

locations, including an estimated eight deaths in detached structures at residential locations (i.e., 

sheds, detached garages) and structures not intended originally as a permanent residence (i.e., 

camper trailers, sea-land shipping containers). From 2007 to 2009, an annual average of 138 CO 

poisoning deaths (82% of all CO fatalities) occurred at home locations. In 2009, an estimated 18

deaths took place in temporary shelters, such as tents, ice fishing sheds, and boats. For 2007 to 

2009, an annual average of 19 CO poisoning deaths (11%) took place in temporary shelters. In 

2009, CO deaths in temporary shelters were most commonly associated with heating sources, 

generators, or lanterns. An estimated 8 of 18 (44%) CO deaths in temporary shelters were 

associated with LP-fueled products, including portable heaters and water heaters. In 2009, an 

estimated eight deaths (44%) in temporary shelters involved generators.

A consistently small percentage of deaths due to CO poisoning involving a consumer 

product occurred in vehicles, such as passenger vans, trucks, automobiles, recreational vehicles, 

campers, or boats. In 2009, there were an estimated 13 (9%) CO fatalities in this category—

most commonly associated with generators (6 deaths), portable LP heaters (3 deaths), and 

charcoal grills (3 deaths). For 2007 to 2009, an annual average of 10 CO poisoning deaths (6%) 

took place in vehicles. 
20 | Page

Table 5: Estimated Non-Fire Carbon Monoxide Poisoning Deaths by Location of Death, 1999−2009

Location of Death

2007−2009+ Annual Estimate

Average 

Estimate 

Average 

Percent 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009+

Total 169 100% 108 138 121 181 153 168 190 180 186 176 146

Home1 124 73% 58 87 78 121 109 121 120 119 138 126 108

Home – External

 Structure2 10 6% 7 8 8 15 11 10 16 14 11 13 7

Home – But Not

 House3 4 2% 6 5 5 8 2 * 6 4 4 6 1

Temporary Shelter 19 11% 28 32 17 32 22 22 32 36 22 16 18

Vehicles (including 

 boats) 10 6% 9 7 13 4 9 8 14 6 8 9 13

Other 2 1% * * * * * 8 2 1 2 3 *

Unknown 1 1% * * * * 2 * * * * 2 *

+ Data collection for 2009 is nearly complete. Italicized estimates may change in the future if more reports of fatalities are received.

* No reports received by CPSC staff.

1 Traditional home (e.g., detached house, townhouse, apartment, mobile home)

2 External structure at residential locations (e.g., detached garage, shed)

3 Non-fixed structure or structure not originally designed for permanent occupation (e.g., camper trailer, van, converted sea-land shipping)

Source: U.S. Consumer Product Safety Commission/EPHA.

 CPSC Death Certificate File, CPSC In-Depth Investigation File, CPSC Injury or Potential Injury Incident File, National Center

 for Health Statistics Mortality File, 1999–2009.

CPSC data indicate that there were more CO fatalities attributable to incidents that 

occurred in the colder months than in the warmer months. This is most likely because of the use 

of furnaces and portable heaters in the colder months. Additionally, generators are often used in 

the winter months because of power outages due to snow and ice storms. Table 6 on the next 

page shows the annual estimated CO fatalities categorized by month of death for the 11 years 

covered by this report. In 2009, 84 of the 146 estimated CO fatalities (58%) are attributable to 

incidents that occurred during the colder months of November, December, January, and 

February. An estimated 42 fatalities (29%) are attributable to incidents that occurred during the 

transition months of March, April, September, and October; and an estimated 21 fatalities (14%)

in the warmer months of May, June, July, and August. Over the 11 years this report spans, an 

estimated 59 percent of CO fatalities are attributable to incidents that occurred during the colder 

months; an estimated 25 percent are attributable to incidents that occurred during the transition 

months; and an estimated 16 percent of fatalities occurred in the warmer months.
21 | Page

Table 6: Estimated Non-Fire Carbon Monoxide Poisoning Deaths by Month and

Year of the Fatality, 1999–2009

Month of Death

2007−2009+ Annual Estimate

Average 

Estimate 

Average 

Percent 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009+

Total 169 100% 108 138 121 181 153 168 190 180 186 176 146

Cold Months 100 59% 59 89 86 94 96 107 98 95 109 107 84

 November 20 12% 7 28 13 27 32 26 18 23 21 28 12

 December 22 13% 16 33 24 26 30 27 33 38 25 22 19

 January 34 20% 28 17 26 20 22 34 37 14 43 31 29

 February 23 14% 8 11 23 21 12 20 10 20 20 26 24

Transition

 Months 42 25% 31 31 28 67 39 41 62 56 49 36 42

 March 13 8% 17 9 3 28 8 10 19 19 19 7 13

 April 10 6% 2 3 13 9 13 8 9 16 15 8 8

 September 4 2% 6 7 5 5 9 14 17 7 1 7 4

 October 15 9% 6 12 7 25 9 9 17 14 14 14 17

Warm Months 27 16% 18 18 7 19 19 19 31 29 29 32 21

 May 10 6% 3 7 5 4 3 5 4 9 9 17 5

 June 7 4% 5 3 * 5 7 6 9 3 4 7 10

 July 4 2% 5 5 * 2 6 4 12 4 5 3 4

 August 6 4% 5 3 2 8 3 4 6 13 11 5 2

+ Data collection for 2009 is nearly complete. Italicized estimates may change in the future if more reports of fatalities are received.

* No reports received by CPSC staff.

Source: U.S. Consumer Product Safety Commission / EPHA.

CPSC Death Certificate File, CPSC In-Depth Investigation File, CPSC Injury or Potential Injury Incident File, National Center for Health 

 Statistics Mortality File, 1999– 2009.

Note: Reported annual estimates and estimated averages and percentages may not add to subtotals or totals due to rounding.

Figure 2 illustrates the relationship between the time of year and the estimated number of 

CO poisoning fatalities. The total estimated number of CO poisoning fatalities is presented on 

the radar graph by month of death. The shaded area represents the estimated total number of 

fatalities for 1999 through 2009, for each month. It can be seen clearly that more CO deaths 

occur in the colder months, particularly, November, December, and January, than in warmer 

months. It also can be seen that as the months after the summer get colder, the number of CO 

fatalities increases. Conversely, as the months after the winter get warmer, the number of 

fatalities decreases.
22 | Page

Figure 2: Estimated Number of Consumer Product-Related Carbon Monoxide 

Deaths by Month of Death, 1999–2009

0

50

100

150

200

250

300

350

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

Deaths
23 | Page

Demographics of Fatalities from Non-Fire Carbon Monoxide Poisoning Associated with the 

Use of Consumer Products

Table 7 shows the estimated number of CO poisoning fatalities categorized by victim age 

for the 11 most recent years of data (1999–2009). From the summary, it appears that consumer 

product-related CO fatalities are skewed toward older individuals. For the three most recent 

years (2007–2009), children younger than 15 years of age accounted for an annual average of 5 

percent (an estimated 9 of 169) of the yearly CO poisoning deaths, while this age group 

represents an average of about 20 percent of the U.S. population. The annual average percentage 

of deaths represented by adults 45 years and older was 59 percent (99 of 169) in 2007 to 2009,

while only about 37 percent of the U.S. population is over 45 years old. In 2007 to 2009, adults 

age 65 years and older accounted for an annual average percentage of 20 percent of CO 

poisoning fatalities, although this age group is about 13 percent of the U.S. population.

6

 Chisquare goodness-of-fit test results indicate that there is a statistically significant difference (pvalue = < 0.0001) between the proportion of CO victims in each age group from that of the 

general U.S. population. Each age group was analyzed separately, versus the expected 

proportion of the respective age group, based on U.S. population figures, assuming there was no 

age group effect on the CO poisoning fatality rate, to determine which age group proportions 

were significantly different from expectation. Binomial tests indicate that three groups were 

found to be significantly different than what would be expected if there was no population group 

effect:

1. The “Under 15” group7 was significantly lower;

2. The “45–64” group was significantly higher; and

3. The “65 and older” group was significantly higher.

Table 7: Estimated Non-Fire Carbon Monoxide Poisoning Deaths by Age of Victim, 1999–2009

Age

2007–2009+ Estimated 

Percentage of 

U.S. Population#

Annual Estimate

Average 

Estimate

Average 

Percent 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009+

Total 169 100% 100% 108 138 121 181 153 168 190 180 186 176 146

Under 5 4 2% 7% * 3 3 2 6 3 * 2 8 2 3

5 - 14 5 3% 13% 7 3 6 9 9 11 7 4 6 8 2

15 - 24 16 9% 14% 8 10 16 11 17 4 17 21 18 16 14

25 - 44 44 26% 27% 31 42 23 56 46 43 46 59 34 55 43

45 - 64 65 38% 26% 45 57 39 51 55 68 86 58 70 66 59

65 and 

over 34 20% 13% 16 23 33 51 21 39 34 36 49 29 25

+ Data collection for 2009 is nearly complete. Italicized estimates may change in the future if more reports of fatalities are received.

* No reports received by CPSC staff.

# Based on average estimated U.S. population statistics for 2007 to 2009.

Source: U.S. Consumer Product Safety Commission/EPHA.

 CPSC Death Certificate File, CPSC In-Depth Investigation File, CPSC Injury or Potential Injury Incident File, National Center for Health Statistics

 Mortality File, 1999 - 2009.

 U.S. Census Bureau, Statistical Abstract of the United States: 2012.

Note: Reported annual estimates and estimated averages and percentages may not add to subtotals or totals due to rounding.

 6 U.S. Census Bureau, Statistical Abstract of the United States: 2010. 7 “Under 5” and “5–14” groups were combined due to small sample sizes.
24 | Page

Table 8 presents the distribution of estimated CO fatalities categorized by gender. In 

2009, 73 percent of CO poisoning victims were males, and 27 percent were females. These

percentages varied slightly from year to year over the 11 years of this report, but every year there 

are many more male CO fatalities than female ones. Over the years, 1999 through 2009, the 

average percentage of male CO victims was 75 percent, and the average percentage of female 

victims was 25 percent. By contrast, about 49 percent of the U.S. population is male, and 51 

percent are female8. Chi-square goodness-of-fit test results indicate that there is a statistically 

significant difference (p-value = < 0.0001) between the proportion of CO victims by gender 

group and that of the general U.S. population.

 Table 8: Estimated Non-Fire Carbon Monoxide Poisoning Deaths by Gender of Victim, 1999-2009

Gender

2007−2009+ Estimated 

Percentage of 

U.S. Population#

Annual Estimate

Average 

Estimate

Average 

Percent 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009+

Total 169 100% 100% 108 138 121 181 153 168 190 180 186 176 146

Male 127 75% 49% 86 105 82 126 118 123 140 145 132 142 107

Female 42 25% 51% 22 34 39 54 37 45 50 36 53 34 39

+ Data collection for 2009 is nearly complete. Italicized estimates may change in the future if more reports of fatalities are received.

# Based on average estimated U.S. population statistics for 2007 to 2009.

Source: U.S. Consumer Product Safety Commission/EPHA.

 CPSC Death Certificate File, CPSC In-Depth Investigation File, CPSC Injury or Potential Injury Incident File, National Center for Health Statistics

 Mortality File, 1999–2009.

 U.S. Census Bureau, Statistical Abstract of the United States: 2012.

Note: Reported annual estimates and estimated averages and percentages may not add to subtotals or totals due to rounding.

Table 9 provides a summary of CO fatality victims characterized by race/ethnicity for the 

years 1999 through 2009. Because of the growing proportion of the U.S. population of Hispanic 

descent, Hispanic victims were categorized separately, irrespective of their race. It should be 

noted that estimates of the percentage of the U.S. population categorized into the various 

race/ethnicity groupings were based on single-race characterizations, as represented in the U.S. 

Census Bureau reports. Multirace population counts were omitted from the calculations. The 

reason for this modification is because death certificates, the primary source of race/ethnicity 

designations, often list only a single race/ethnicity designation. 

The estimated percentage of the 2007–2009 annual average of non-Hispanic white CO 

fatalities closely mirrors the percentage of the U.S. population9 at 67 percent and 66 percent, 

respectively. However, there appears to be a disproportionate number of Black or African 

American victims of CO poisoning, comprising 17 percent of all CO poisoning fatalities, even 

though Blacks or African Americans represent only about 12 percent of the U.S. population. By 

contrast, the proportion of the CO poisoning fatality victims who were of Hispanic ethnicity

(9%) is below the percentage of Hispanics in the U.S. population (15%). Chi-square goodnessof-fit test results indicate that there is a marginally non-significant statistical difference (p-value 

= 0.0898) between the proportion of CO victims categorized by race/ethnicity from that of the 

general U.S. population. Each race/ethnicity group was analyzed separately, versus the expected 

proportion of the respective race/ethnicity group based on U.S. population figures, assuming 

 8 Average of 2012 U.S. Census estimates for 2007 through 2009 for the U.S. population.

9 The “percentage of the U.S. population” is defined here as the average of the 2012 U.S. Census estimates for 2007 

through 2009 for the U.S. population.
25 | Page

there was no race/ethnicity group effect on the CO poisoning fatality rate, to determine which 

race/ethnicity group proportions were significantly greater than or less than the expectation. 

Binomial tests indicate that one race/ethnicity group was statistically significantly different from 

the expected proportion based on the U.S. population. The observed proportion of Hispanic CO 

fatalities was significantly lower (p-value < 0.05) than the proportion of Hispanics in the U.S. 

population. Additionally, the observed proportion of Black or African American CO fatalities 

was marginally significantly higher (p-value < 0.10) than the proportion of Black or African 

Americans in the U.S. population.

Table 9: Estimated Non-Fire Carbon Monoxide Poisoning Deaths by Race/Ethnicity, 1999−2009

Country of Origin

2007−2009+ Estimated 

Percentage of 

U.S. Population#

Annual Estimate

Average 

Estimate

Average 

Percent 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009+

Total 169 100% 100% 108 138 121 181 153 168 190 180 186 176 146

 White (non-Hispanic) 113 67% 66% 57 101 86 138 102 116 134 107 122 123 93

 Black or 

 African American 28 17% 12% 30 22 19 20 26 27 36 36 35 30 20

 Hispanic (All races) 16 9% 15% 13 10 9 14 14 20 15 19 23 15 11

 Asian / Pacific 2 1% 5% 6 2 1 4 10 2 2 13 3 1 3

 American Indian 1 1% 1% 2 2 3 2 2 0 0 6 1 2 1

 Unknown / Other 8 5% 1% 0 1 1 1 0 2 2 0 2 4 19

+ Data collection for 2009 is nearly complete. Italicized estimates may change in the future if more reports of fatalities are received.

* No reports received by CPSC staff.

# Based on average estimated U.S. population statistics for 2007 to 2009.

Source: U.S. Consumer Product Safety Commission / EPHA.

 CPSC Death Certificate File, CPSC In-Depth Investigation File, CPSC Injury or Potential Injury Incident File, National Center for Health Statistics

 Mortality File, 1999–2009.

 U.S. Census Bureau, Statistical Abstract of the United States: 2012.

Note: Reported annual estimates and estimated averages and percentages may not add to subtotals or totals due to rounding.

Table 10 provides a breakout of the CO poisoning fatalities characterized by population 

density of the incident location. The table is presented as three sections: (1) incidents occurring 

at all incident locations; (2) incidents occurring in locations identified as a permanent home (e.g., 

house, apartment, mobile home); and (3) incidents occurring only in non-home locations (e.g., 

camper trailer, tent, motel room). Please note that “Home Locations” and “Non-Home 

Locations” sum to “All Locations.” 

All fatal incidents were designated as occurring in one of four rural/urban categories 

based on the Rural-Urban Commuting Area (RUCA) codes developed by the Economic 

Research Service (ERS) of the U.S. Department of Agriculture (USDA). The categories are 

based on theoretical concepts used by the U.S. Office of Management and Budget (OMB) to 

define county-level metropolitan and micropolitan areas. This 33-category classification system 

is based on measures of population density, urbanization, and daily commuting. The OMB 

methodology is based on a county-level delineation. ERS refined the methodology by applying 

it to smaller census tracts. The WWAMI Rural Health Research Center at the University of 

Washington10 further delineated the characterization by cross-referencing each zip code in the 

United States to its RUCA code classification. The zip code cross-reference was used to 

 

10 The WWAMI name is derived from the first letter of each of the five cooperating states in a partnership between 

the University of Washington School of Medicine and the states of Wyoming, Alaska, Montana, and Idaho. 
26 | Page

characterize each of the CO fatalities into one of four broad categories: Urban Core, Sub-Urban, 

Large Rural Town, and Small Town/Rural Isolated.

Table 10 also includes the estimated percentage of the U.S. population, per population 

density designation category. As can be seen in the All Locations section, the estimated average 

percentage of CO fatalities during the 3-year period 2007 through 2009, in urban locations 

(55%), is smaller than the percentage of the U.S. population living in urban core locations (71%). 

The difference is offset by the larger percentages the other three categories: sub-urban locations

(12% versus 10% of the U.S. population), large rural town locations (14% versus 10%), and 

small town/rural isolated locations (20% versus 9%). A look at the Non-Home Locations section 

helps to identify some of the disparity. An average of 29 percent of all non-home CO fatalities 

occurred in small town/rural isolated locations, even though the U.S. population living in isolated 

locations is only 9 percent. In 2007 through 2009, an estimated average of 9 of 33 CO poisoning 

fatalities in small town/rural isolated locations occurred in non-home locations. Two factors may 

help to explain the relatively high proportion of small town/isolated rural location CO fatalities. 

Many non-home locations where CO fatalities occurred were tents, camper trailers, or cabins in 

isolated locations, used during hunting or camping activities where no local power utility is 

available. In these cases, individuals often resort to generators for power and use portable LP 

heaters, lanterns, and stoves.

Another possible factor in the elevated percentage of small town/isolated rural location 

CO fatalities is the isolated nature itself. Being isolated from friends, family, and neighbors, 

victims often have little day-to-day interaction with others, so discovery is often days later,

instead of perhaps, hours, which could make the difference between life and death. Small towns 

or isolated rural location may also be a factor when it comes to rescue and hospital services,

which may be very far away.
27 | Page

Table 10: Estimated Non-Fire Carbon Monoxide Poisoning Deaths by Population 

Density of Place of Death, 1999–2009

RUCA Population 

Density Designation

2007−2009+ Estimated 

Percentage of 

U.S. Population#

Annual Estimate

Average 

Estimate

Average 

Percent 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009+

All Locations 169 100% 100% 108 138 121 181 153 168 190 180 186 176 146

 Urban Core

 Sub-Urban

 Large Rural Town

 Small Town / 

 Rural Isolated

93

21

23

33

 55%

 12%

 14%

 20%

71%

10%

10%

 9%

60

7

20

22

83

20

11

25

68

22

16

15

100

24

31

26

110

11

8

25

112

27

14

15

119

21

20

30

122

22

12

23

110

19

18

39

96

20

37

23

72

23

13

38

Home Locations 138 100% 100% 70 101 90 144 121 131 141 139 153 145 116

 Urban Core

 Sub-Urban

 Large Rural Town

 Small Town / 

 Rural Isolated

78

17

19

24

 57%

 12%

 14%

 17%

71%

10%

10%

 9%

53

3

8

6

70

16

7

8

52

17

11

10

86

19

27

12

92

11

8

10

91

21

10

9

89

19

18

15

107

16

8

8

93

16

16

28

81

18

28

18

61

16

13

26

Non-Home Locations 31 100% 100% 37 37 31 36 32 36 48 43 32 30 31

 Urban Core

 Sub-Urban

 Large Rural Town

 Small Town / 

 Rural Isolated

15

4

3

9

 47%

 13%

 11%

 29%

71%

10%

10%

 9%

7

3

12

15

13

3

4

17

16

5

5

5

14

4

4

14

17

*

*

15

20

5

4

7

30

2

2

14

16

7

4

16

17

3

2

10

15

2

8

5

12

7

*

12

+ Data collection for 2009 is nearly complete. Italicized estimates may change in the future if more reports of fatalities are received.

* No reports received by CPSC staff.

# Estimated 2010 U.S. population categorized by RUCA designation. U.S. population estimates by RUCA classification were determined from by cross-referencing the 

 WWAMI RUCA zip code table with the 2010 U.S. Census population estimates by zip code area, the most current census data available by zip code area.

Source: U.S. Consumer Product Safety Commission/EPHA.

 CPSC Death Certificate File, CPSC In-Depth Investigation File, CPSC Injury or Potential Injury Incident File, National Center for Health Statistics

 Mortality File, 1999–2009.

 U.S. Census Bureau, Statistical Abstract of the United States: 2010.

Note: Reported annual estimates and estimated averages and percentages may not add to subtotals or totals due to rounding.

Table 11 provides a breakout of the CO poisoning fatalities characterized by geographic 

region where the incident occurred. As can be seen in the table, for the most part, the percentage 

of CO fatalities in each of the regions reflects the percentage of the U.S. population living in 

these regions. This would indicate that geographic location has little effect on the likelihood of 

fatal CO poisoning incidents. There are, however, a few exceptions that should be pointed out. 

The Midwest region, as a whole, exhibited a far greater than expected number of CO deaths. 

Thirty percent of the estimated CO fatalities in 2007 through 2009 occurred in Midwest states 

where only 22 percent of the U.S. population live. The Mountain states of the West region also 

had a greater than expected number of CO deaths compromising 11 percent of the deaths, yet 

home to only seven percent of the population. Conversely, the South Atlantic states of the South 

region accounted for 12 percent of the CO deaths where 19 percent of the U.S. population live. 

The Pacific states of the West region also accounted for fewer CO deaths than expected (9% of 

the deaths, 16% of the population).
28 | Page

Table 11: Estimated Non-Fire Carbon Monoxide Poisoning Deaths by Geographical Region 

of Incident, 1999–2009

Region‡

2007–2009+

Estimated 

Percentage of 

US Population#

Annual Estimates

Average 

Estimate

Average 

Percent 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009+

Total 169 100% 100% 108 138 121 181 153 168 190 180 186 176 146

North East 28 17% 18% 12 20 11 18 24 16 33 24 44 27 12

 New England 9 5% 5% 1 1 1 6 3 7 7 8 10 11 5

 Middle Atlantic 19 11% 13% 10 19 10 12 21 10 26 16 34 16 7

South 56 33% 37% 37 49 38 69 53 58 74 57 61 52 55

 South Atlantic 20 12% 19% 28 17 11 38 25 21 41 26 25 21 13

 East South Central 13 8% 6% 3 8 6 12 15 16 9 10 9 10 19

 West South Central 24 14% 12% 6 24 21 19 12 21 24 21 27 21 23

Midwest 51 30% 22% 28 46 28 58 41 49 46 54 47 59 48

 East North Central 31 18% 15% 17 37 14 38 34 30 31 40 25 40 28

 West North Central 20 12% 7% 10 9 14 20 7 19 15 14 22 19 20

West 34 20% 23% 31 24 44 33 33 37 33 46 33 37 31

 Mountain 19 11% 7% 20 17 24 21 12 20 18 21 17 22 17

 Pacific 16 9% 16% 12 7 20 12 20 16 15 24 17 16 15

‡ Region designation is based on U.S. Census Bureau reporting practices. See Appendix C for identification of specific regional designation of state of

occurrence.

+ Data collection for 2009 is nearly complete. Italicized estimates may change in the future if more reports of fatalities are received.

# Based on estimated 2006 U.S. population statistics. This is the latest available data for this Density Designation characterization and represents a midpoint value in the 

2006 to 2008 range.

Source: U.S. Consumer Product Safety Commission/EPHA.

 CPSC Death Certificate File, CPSC In-Depth Investigation File, CPSC Injury or Potential Injury Incident File, National Center for Health Statistics

 Mortality File, 1999–2009.

 U.S. Census Bureau, Statistical Abstract of the United States: 2010.

Note: Reported annual estimates and estimated averages and percentages may not add to subtotals or totals due to rounding.
29 | Page

Appendix A: Methodology

This appendix describes the data sources and methodology used to compute the national 

estimate of non-fire carbon monoxide (CO) poisoning deaths associated with the use of 

consumer products and the estimates by product, victim age, and incident location.

All death certificates filed in the United States are compiled by the National Center for 

Health Statistics (NCHS) into a multiple cause of mortality data file. The NCHS Mortality File 

contains demographic and geographic information, as well as the International Statistical 

Classification of Diseases and Related Health Problems codes for the underlying cause of death. 

Data are compiled in accordance with the World Health Organization instructions, which request 

that member nations classify causes of death by the current Manual of the International 

Statistical Classification of Diseases and Related Health Problems. The International 

Classification of Diseases, Tenth Revision (ICD-10) was implemented in 1999. Although the 

NCHS data contain cause of death codes that are helpful in identifying deaths due to CO 

poisoning, the records do not contain any narrative information that might indicate the 

involvement of a consumer product.

To complement the NCHS mortality data, CPSC staff purchases death certificates from 

the 50 states, the District of Columbia, and New York City. Specifically, CPSC staff purchases 

death certificates with certain cause of death codes for which there is a high probability that 

consumer products are involved. In addition to the cause-of-death codes and demographic and 

geographic information, the death certificate contains information about the incident location and 

a brief narrative describing the incident. Any references to consumer products are usually found 

in these narratives. As resources allow, CPSC staff conducts follow-up In-Depth Investigations 

on selected deaths to confirm and expand upon the involvement of consumer products.

ICD-10 classifies deaths associated with CO poisoning with the codes listed below. The 

focus of this report is unintentional CO poisoning deaths and concentrates on deaths coded as 

X47 and Y17. That is, code X67─records of intentional CO poisonings─are excluded from this 

analysis.

ICD-10 Code Definition

X47 Accidental– Poisoning by and exposure to other gases and vapors.

Includes: carbon monoxide, lacrimogenic gas, motor (vehicle) exhaust gas, 

nitrogen oxides, sulfur dioxide, utility gas.

X67 Intentional– Poisoning by and exposure to other gases and vapors.

Includes: carbon monoxide, lacrimogenic gas, motor (vehicle) exhaust gas, 

nitrogen oxides, sulfur dioxide, utility gas.

Y17 Undetermined intent– Poisoning by and exposure to other gases and vapors.

Includes: carbon monoxide, lacrimogenic gas, motor (vehicle) exhaust gas, 

nitrogen oxides, sulfur dioxide, utility gas.

The first step in compiling the annual estimates is computing the total estimates of CO 

poisoning deaths associated with consumer products. The CPSC’s Death Certificate (DTHS) 
30 | Page

File and the CPSC’s Abbreviated Death Certificate (ABDT) File were searched for cases 

associated with ICD-10 codes X47 and Y17. 

Each death found in the CPSC’s DTHS File and coded as X47 or Y17 was reviewed by 

an analyst and categorized as in scope, out of scope, or whether the source of the CO was 

unknown or questionable. In-scope cases are unintentional, non-fire CO poisoning deaths 

associated with a consumer product under the jurisdiction of the CPSC. Out-of-scope cases are 

cases that involve CO sources that are not under the jurisdiction of the CPSC (including motor 

vehicle exhaust cases), fire or smoke-related exposures, or intentional CO poisonings. Examples 

of out-of-scope cases include: poisonings due to gases other than CO (i.e., natural gas, ammonia, 

butane); motor vehicle exhaust- or boat exhaust-related poisonings; and work-related exposures. 

The source of CO was classified as unknown or questionable in cases where a consumer product 

was possibly associated with the incident, but the exact source of CO was unknown. 

Deaths found in the CPSC’s ABDT File are categorized as out-of-scope cases. The 

ABDT File contains death certificates for CO poisonings (X47 and Y17) that involve motor 

vehicle exhaust, cases where the source of the CO is unknown, or where the death certificate 

does not mention a consumer product. Other examples of out-of-scope cases that may appear in 

the abbreviated file are cases associated with farm accidents, smoke inhalation from a structural 

fire, or other gas poisonings. Occasionally, newer information from CPSC In-Depth 

Investigations (IDIs) may be matched with ABDT cases that were classified as having no known 

source or did not mention a consumer product. In the cases where the CPSC IDIs indicate the 

CO source was from a consumer product and should be considered in scope, it was assumed that 

the death certificate was misclassified, and the subject cases in the ABDT File were included

with the DTHS database files. 

In previous years, a small number of cases in the ABDT File were identified as in scope,

based on further information collected during IDIs. The method used to identify three deaths in 

1999, and two deaths in 2000, is found in Appendix A of the 1999 and 2000 Annual Estimate 

Report (Vagts, 2001). For 2001 data, no ABDT File cases were reclassified as in scope, based 

on additional information. For the 2002 data, additional information on one incident in the 

ABDT File resulted in the incident being reclassified as in scope. This fatality was not included 

in the NCHS file. Because the incident was not included in the NCHS data, it was also removed 

from the ABDT File, and thus, it was not used in calculations for the weights. For the 2003 data,

there were seven reclassified in-scope cases in the ABDT File and five in 2004. For the 2005 

data, one case from the ABDT File was reclassified as an in-scope case. For the 2006 data, three 

cases from the ABDT were reclassified. And for 2007, three more cases were reclassified. For 

2008 and 2009, no ABDT records were reclassified as in-scope.

Since the release of the previous annual report, additional records have been entered into 

the CPSC databases, and therefore, the resultant initial categorization for 2007 through 2009 has

been recalculated and is presented in Tables A.1.a through A.1.c.
31 | Page

Table A.1.a: Initial Categorization for 2007 Data

ICD-10 

Code

NCHS 

Total

DTHS File

Total in 

ABDT File

Total in 

CPSC 

Databases1

Number of 

Cases to be 

Imputed2

In-Scope Unknown 

Scope

Out-ofScope Total

X47 605 173 10 235 418 172 590 25

Y17 89 4 4 34 42 30 72 21

Total 694 177 14 269 460 202 662 46

Table A.1.b: Initial Categorization for 2008 Data

ICD-10 

Code

NCHS 

Total

DTHS File

Total in 

ABDT File

Total in 

CPSC 

Databases1

Number of 

Cases to be 

Imputed2

In-Scope Unknown 

Scope

Out-ofScope Total

X47 677 161 22 198 381 290 671 28

Y17 68 6 6 22 34 25 59 15

Total 745 167 28 220 415 315 730 43

Table A.1.c: Initial Categorization for 2009 Data

ICD-10 

Code

NCHS 

Total

DTHS File

Total in 

ABDT File

Total in 

CPSC 

Databases1

Number of 

Cases to be 

Imputed2

In-Scope Unknown 

Scope

Out-ofScope Total

X47 734 143 16 230 389 361 750 0

Y17 72 2 5 23 30 22 52 25

Total 806 145 21 253 419 383 802 25

1 “Total in ABDT File” cases, plus “Total” from DTHS File.

2 “NCHS Total” cases, minus “Total in CPSC Database,” plus “Unknown Scope” from DTHS.

Source: U.S. Consumer Product Safety Commission/EPHA. 

CPSC Death Certificate File, CPSC In-Depth Investigation File, Abbreviated Death Certificate File, National Center for Health 

Statistics Mortality File, 2007–2009.

The proportion of death certificates found in the CPSC database associated with non-fire 

unintentional X47 or Y17 deaths and associated with consumer products was applied to the 

NCHS totals to calculate the total estimated number of non-fire CO poisoning deaths associated 

with consumer products. In theory, the NCHS totals comprise all death certificates in the United 

States, and the same proportion of in-scope cases should exist in the death certificates that are 

missing from the combined CPSC Death Certificate and Abbreviated Death Certificate files or 

are from an unknown source. Applying the proportion of in-scope cases to the NCHS database 

totals, therefore, should provide an estimate of in-scope cases nationwide. This was done in the 

following way and was done for ICD-10 codes X47 and Y17, separately:
32 | Page

1. The number of in-scope deaths in the CPSC’s Death Certificate File coded as X47 or Y17 

separately that were associated with an accidental non-fire CO poisoning and a consumer 

product were identified (n1).

2. The total number of deaths in the CPSC’s Death Certificate File and the Abbreviated 

Death Certificate File coded as X47 or Y17 were summed separately, excluding cases with an 

unknown or highly questionable source (n2).

3. The total number of deaths in the NCHS data associated with X47 and Y17 was counted 

(n3).

4. The estimate of the number of non-fire CO poisoning deaths associated with consumer 

products in codes X47 and Y17 was calculated separately, using the formula:

N= (n1 / n2) * n3

The proportion (n1 /n2) represents the number of in-scope cases found in the CPSC’s files,

divided by the total of in-scope and out-of-scope cases. 

5. The estimates of the number of non-fire CO poisoning deaths associated 

with consumer products in codes X47 and Y17 were summed to calculate the total 

estimate of non-fire CO poisoning deaths.

Total Estimate = NX47 + NY17

The ratio (n3 / n2) represents the weighting factor used to calculate the annual estimates. 

The CPSC’s Death Certificate File does not contain death certificates for all deaths listed in the 

NCHS file; therefore a weighting factor was calculated to account for death certificates that are 

missing. The weighting factor allows the computation of national estimates of CO deaths by 

consumer products and by other characteristics collected by CPSC about each death.

Table A.2 contains the values for the variables used in the calculation, as well as the final 

computed 2008 estimate of CO poisoning deaths. 

Table A.2.a: Calculation Detail of the Final Computed 2007 Estimate of Non-Fire CO 

Poisoning Deaths Associated with Consumer Products

Variable

ICD-10 Code

X47 Y17

n1 173 4

n2 590-10 = 580 72-4 = 68

n3 605 89

Weighting Factor (n3 / n2) 1.0431 1.3088

N 180.4569 5.2353

Total Estimate {180.4569 + 5.2353 = 185.6922 ~ 186}
33 | Page

Table A.2.b: Calculation Detail of the Final Computed 2008 Estimate of Non-Fire CO Poisoning 

Deaths Associated with Consumer Products

Variable

ICD-10 Code

X47 Y17

n1 161 6

n2 671-22 = 649 59-6 = 53

n3 677 68

Weighting Factor (n3 / n2) 1.0431 1.283

N 167.9461 7.6981

Total Estimate {167.9461 + 7.6981 = 175.6442 ~ 176}

Table A.2.c: Calculation Detail of the Final Computed 2009 Estimate of Non-Fire CO Poisoning 

Deaths Associated with Consumer Products

Variable

ICD-10 Code

X47 Y17

n1 143 2

n2 750-16 = 734 52-5 = 47

n3 734 72

Weighting Factor (n3 / n2) 1 1.5319

N 143.0000 3.0638

Total Estimate {143 + 3.0638 = 146.0638 ~ 146}

Source: U.S. Consumer Product Safety Commission/EPHA. 

CPSC Death Certificate File, CPSC In-Depth Investigation File, Abbreviated Death Certificate File, National 

Center for Health Statistics Mortality File, 2008.

It should be noted that death certificates received by NCHS are routinely checked for 

accuracy of state personnel identified ICD-10 coding. On occasion, NCHS staff will correct 

codes before entering the data into their databases. The death certificate facsimiles or electronic 

death certificates that CPSC receives are direct from the states, and therefore, have not been 

corrected per NCHS procedures. As a consequence, there may be slight discrepancies between 

final NCHS counts and CPSC records, which are not due to CPSC simply not having the records, 

but instead, may be due to corrections made at NCHS. Because CPSC receives the death 

certificates directly from the states, CPSC records do not contain information from NCHS when 

an ICD-10 code changed for a specific death certificate; so CPSC staff has no way of correcting 

CPSC records to come into accord with NCHS records. For this report, CPSC staff have made 

the assumption that, over time, the number of death certificates with ICD-10 codes changed by 

NCHS staff to the codes of interest (X47 and Y17) would approximately equal those changed 

from the code of interest. 

Table A.3 shows the weighting factors used to calculate the estimates for the years 1999–

2009, based on the information available to CPSC staff.
34 | Page

Table A.3: CO Fatality Cases and Weighting Factors Used to Calculate the 

Estimates for the Years 1999–2009

Year NCHS Total

Total in 

CPSC 

Databases*

In-Scope 

Cases+ Weighting Factor

1999

X47 542 469 92 1.1557

Y17 80 66 1 1.2121

2000

X47 600 551 126 1.0889

Y17 76 70 1 1.0857

2001

X47 596 520 102 1.1462

Y17 79 62 3 1.2742

2002

X47 642 599 168 1.0718

Y17 71 61 1 1.1639

2003

X47 633 625 149 1.0128

Y17 89 75 2 1.1867

2004

X47 566 527 154 1.0740

Y17 86 72 2 1.1944

2005

X47 650 590 171 1.1017

Y17 92 70 1 1.3143

2006

X47 585 527 161 1.1101

Y17 74 53 1 1.3962

2007

X47 605 580 173 1.0431

Y17 89 68 4 1.3088

2008

X47 677 649 161 1.0431

Y17 68 53 6 1.2830

2009

X47 734 734 143 1.0000

Y17 72 47 2 1.5319

+ For some years, the number of in-scope cases has changed slightly from the previous report, due to either newly obtained 

information or a recharacterization of a few cases.

* This is the total number of deaths in the Death Certificate File and Abbreviated Death Certificate File, excluding deaths associated 

with an unknown or questionable source of CO. 

Source: U.S. Consumer Product Safety Commission/EPHA. 

CPSC Death Certificate File, CPSC In-Depth Investigation File, Abbreviated Death Certificate File, 

National Center for Health Statistics Mortality File, 1999–2009.
35 | Page

Incidents with unknown or highly questionable CO sources were excluded from the 

denominator (the number of fatalities in the CPSC databases) of the weighting factor. The group 

of cases with unknown or highly questionable sources was assumed to contain the same 

proportion of cases associated with a consumer product as the group of cases within the CPSC 

database with known CO sources (this is the same assumption that is made for those cases where 

the death certificate is missing). To include these cases within the denominator assumes that 

these cases can be classified as in-scope or out-of-scope cases, when actually their scope status is 

unknown. Therefore, for weighting purposes, cases where the source was unknown, or highly 

questionable, were treated in the same way as missing cases were treated.

In-scope cases were examined further to determine which product was associated with 

the incident. Further information on the CO deaths was obtained from review of the CPSC’s IDI

File.

Reports of non-fire CO poisoning deaths were retrieved from the DTHS and ABDT files 

based on the following criteria: date of death between 1/1/1999 and 12/31/2009, and ICD-10 

code of X47 or Y17. Death certificates entered into the CPSC’s database prior to July 23, 2012,

were included in this analysis. Whenever possible, each CO death was reviewed and coded by 

the author, according to the consumer product and type of fuel involved, incident location, and 

whether multiple deaths resulted in the same incident. If information about the product’s 

condition, venting system, or installation environment was provided in the IDI report, then this 

information was coded for informational purposes.

In Table 1 of this report, the Heating Systems category includes CO poisoning fatalities 

from subcategories for furnaces and boilers (combined under the heading of Furnaces), vented 

floor and wall heaters, unvented room/space heaters, unvented portable heaters, and other 

miscellaneous heating systems. Each subcategory is further delineated by fuel type used. Deaths 

associated with charcoal being burned alone and in the absence of an appliance (e.g., in a pail or 

in the sink) were presented with Charcoal Grills, even though this practice usually was done for 

heating purposes. Examples of products historically included in the Other Products category 

include LP gas refrigerators and gas pool heaters. LP gas grill, LP fish cooker, and other LP gas 

portable cooking appliance incidents are classified in the Grills, Camp Stoves category. Deaths 

where multiple fuel-burning products were used simultaneously, such that a single source of the 

fatal CO could not be determined, were classified under Multiple Products. Engine-Driven

Tools included generators and power gardening equipment, such as power lawn mowers, garden 

tractors, concrete cutters, gasoline-powered water pumps, and snow blowers. Generators that 

were original equipment installed on a recreational vehicle (RV), trailer, camper, or boat were 

considered out of scope, as they are outside the jurisdiction of the CPSC.
36 | Page

Appendix B: National Estimates of Consumer Product-Related CO Poisoning Deaths, 1980 

to 2009

Figure B.1 below graphically suggests a trend of the estimated CO fatalities from 1980 to 

2009. Before the implementation of the ICD-10 coding in 1999, the estimated number of nonfire, consumer product-related CO poisoning deaths decreased from the early 1980s to the late 

1990s, from a high of 340 in 1982, to a low of 180 in both 1997 and 1998. In 1999, there were 

an estimated 108 consumer product-related CO fatalities, well below the estimated 180 deaths in 

each of the two previous years. The difference may be due, in part, to the change from ICD-9 

coding to ICD-10 coding, where product identification could be assessed more accurately.

Figure B.1: Estimated Non-Fire CO Poisoning Deaths Associated with 

Consumer Products: 1980–2009

* Implementation of ICD-10.

Table B.1 presents the annual estimates from 1980 to 2009, and the 3-year average 

mortality rates associated with each year, where 3 years of data were available. The 3-year 

average mortality rate is presented in the table for the mid-point year. The estimated 3-year 

average mortality rate decreased from the 1982 high of 14.02 per 10 million population, to a 3-

year average rate of 4.34 per 10 million in 2000, a reduction of 69 percent. Subsequently, the 3-

year average rate has been increasing annually through 2006, to a rate of 6.21. The current 2008

estimate of 5.56 is slightly less than the previous 2 years, but still 28 percent above the 2000 low 

average. The year 2008 is the last year for which data are available to calculate a 3-year average.

0

50

100

150

200

250

300

350

400

1980198119821983198419851986198719881989199019911992199319941995199619971998

1999*

2000200120022003200420052006200720082009

ICD-9 ICD-10
37 | Page

Table B.1: Estimated Non-Fire Carbon Monoxide Poisoning Deaths Associated

with Consumer Products, 1980−2009

Year Estimate

U.S. Population 

Estimates 

(thousands)

3-Year Average 

Mortality Rate per 10 

Million Population

1980 282 227,225

1981 311 229,466 13.55

1982 340 231,664 14.02

1983 323 233,792 13.38

1984 275 235,825 12.47

1985 284 237,924 11.19

1986 240 240,133 10.49

1987 232 242,289 9.77

1988 238 244,499 10.44

1989 296 246,819 10.49

1990 243 249,623 10.53

1991 250 252,981 9.27

1992 211 256,514 8.77

1993 214 259,919 8.31

1994 223 263,126 8.08

1995 201 266,278 8.02

1996 217 269,394 7.40

1997 180 272,647 7.05

1998 180 275,854 5.66

1999* 108 279,040 5.09

2000 138 282,172 4.34

2001 121 285,082 5.15

2002 181 287,804 5.27

2003 153 290,326 5.76

2004 168 293,046 5.81

2005 190 295,753 6.06

2006 180 298,593 6.21

2007 186 301,580 5.99

2008 176 304,375 5.56

2009 146 307,007

Note: The 3-year average mortality rate is reported at the mid-point year.

* The Tenth Revision of the International Statistical Classification of Diseases and Related Health Problems (ICD-10) was 

implemented.

Source: U.S. Consumer Product Safety Commission/EPHA. 

U.S. Census Bureau, Statistical Abstract of the United States: 2012 (excluding Armed Forces overseas).

Prior to 1999 with the implementation of ICD-10, it was not possible to generate 

estimates for an important category of products: generators and other engine-driven tools.

11 

With the advent of ICD-10 coding, it is now possible to generate estimates of fatalities associated 

with generators and other engine-driven tools. This category has been observed to have a 

 11 See Appendix B of Mah (2001) for details.
38 | Page

statistically significant upward trend in the estimated number of associated CO poisoning 

fatalities since 1999 (pages 13–14). This increasing trend appears to be having an impact on the 

mortality rate of consumer product-related CO poisoning fatalities. Table B.2 shows that the 

2008, 3-year average mortality rate (2.30) for generators alone was more than four times greater 

than for the 2000, 3-year average rate (0.54), and the estimated 3-year average rate has increased 

each year from 2000 through 2006, with a slight decrease in 2007 and 2008. In each of the last 5

years (2005 through 2009), there were more CO fatalities associated with engine-driven tools 

than with heating systems. These are the only years since the implementation of ICD-10 that 

there were more EDT-associated CO deaths than heating system-associated CO deaths. 

Table B.2: Estimated Non-Fire Carbon Monoxide Poisoning Deaths Associated

with Generators, 1999−2009

Year Estimate+ U.S. Population 

(thousands)

3-Year Average 

Mortality Rate per 10 

Million Population

1999 7 279,040

2000 19 282,172 0.54

2001 20 285,082 0.95

2002 42 287,804 1.29

2003 49 290,326 1.52

2004 41 293,046 2.02

2005 88 295,753 2.41

2006 85 298,593 2.69

2007 68 301,580 2.43

2008 77 304,375 2.30

2009 65 307,007

+ Estimates in this table do not include multiple product-related deaths because a generator was not the 

sole product associated with the fatality.

Note 1: The 3-year average mortality rate is reported at the mid-year population estimates.

Note 2: Mortality rate changes from last year’s report are due to changes in CPSC CO death estimates 

and changes in U.S. Census population estimates.
39 | Page

Table B.3 shows the CO poisoning mortality rates associated with all consumer products,

excluding generators. The data indicate that with the exclusion of generators, there does not 

appear to be a trend in the mortality rate for consumer products. The 2000, 3-year annual 

average mortality rate was 3.79. The 2008, 3-year average mortality rate was 3.26, a decrease of 

14 percent. In fact, the 3-year averages have dropped slightly each year since the 2003 high 

point. With generators included, the mortality rate increased from 4.34 per 10 million to 5.56 in 

the same time span, an increase of 28 percent.

Table B.3: Estimated Non-Fire Carbon Monoxide Poisoning Deaths Associated with 

Consumer Products, 1999–2009 (Excluding Generator-Related Deaths)

Year Estimate U.S. Population 

(thousands)

3-Year Average 

Mortality Rate per 10 

Million Population

1999 101 279,040

2000 119 282,172 3.79

2001 101 285,082 4.20

2002 139 287,804 3.99

2003 104 290,326 4.25

2004 127 293,046 3.79

2005 102 295,753 3.65

2006 95 298,593 3.52

2007 118 301,580 3.45

2008 99 304,375 3.26

2009 81 307,007

+ Excludes estimates of deaths associated with a generator only.

Note 1: The 3-year average mortality rate is reported at the mid-year population estimates.

Note 2: Mortality rate changes from last year’s report are due to changes in CPSC CO death estimates 

and changes in U.S. Census population estimates.
40 | Page

Table B.4 shows the mortality rates of all engine-driven tools, including generators

through 2008. Even though the average mortality rate in 2007 and 2008 dropped slightly since 

the 2006 high (3.18), it can be seen in the table that the average mortality rate has more than 

tripled from the 2000, 3-year average rate (0.72), to the average rate for 2008 (2.65).

Table B.4: Estimated Non-Fire Carbon Monoxide Poisoning Deaths Associated with 

Generators and Other Engine-Driven Tools, 1999–2009

Year Estimate U.S. Population 

(thousands)

3-Year Average 

Mortality Rate per 10 

Million Population

1999 13 279,040

2000 26 282,172 0.72

2001 22 285,082 1.17

2002 52 287,804 1.51

2003 56 290,326 1.88

2004 56 293,046 2.43

2005 102 295,753 2.95

2006 104 298,593 3.18

2007 79 301,580 2.86

2008 85 304,375 2.65

2009 78 307,007

+ Estimates in this table do not include multiple product-related deaths because an EDT was not the sole 

product associated with the fatality. The one exception to this is the 2001 estimate that includes one 

estimated death associated with a generator and another EDT.

Note 1: The 3-year average mortality rate is reported at the mid-year population estimates.

Note 2: Mortality rate changes from last year’s report are due to changes in CPSC CO death estimates 

and changes in U.S. Census population estimates.
41 | Page

Table B.5 shows the CO mortality rates associated with all consumer products, excluding 

generators and other engine-driven tools. The data indicate that the annual average, 3-year 

mortality rate decreased by 20 percent of non-engine-driven tool consumer products, with the 

2000 average mortality rate of 3.62 and 2.91 in 2008. When all products are included, there has 

been a 28 percent increase in the CO mortality rate from the 2000 average rate, increasing from 

3-year average mortality rate of 4.34 in 2000, to 5.56 in 2008. Engine-driven tools and 

generators, in particular, have had a substantial impact on the CO poisoning mortality rate 

involving consumer products.

Table B.5: Estimated Non-Fire Carbon Monoxide Poisoning Deaths Associated with Consumer 

Products, 1999−2009 (Excluding Generator- and Other Engine-Driven Tool-Related Deaths)

Year Estimate U.S. Population 

(thousands)

3-Year Average 

Mortality Rate per 10 

Million Population

1999 95 279,040

2000 112 282,172 3.62

2001 99 285,082 3.98

2002 129 287,804 3.77

2003 97 290,326 3.88

2004 112 293,046 3.38

2005 88 295,753 3.11

2006 76 298,593 3.02

2007 107 301,580 3.03

2008 91 304,375 2.91

2009 68 307,007

+ Excludes estimates of deaths associated with EDTs only. Multiproduct-associated incidents are 

included here because an EDT could not be identified as the only product involved. The one exception to 

this is the 2001 estimate, which excludes one estimated death associated with a generator and another 

EDT.

Note 1: The 3-year average mortality rate is reported at the mid-year population estimates.

Note 2: Mortality rate changes from last year’s report are due to changes in CPSC CO death estimates 

and changes to U.S. Census estimates.
42 | Page

Appendix C: Regional Definitions

1) Northeast comprises New England and Middle Atlantic states. 

a) New England: Maine, New Hampshire, Vermont, Massachusetts, Rhode Island, and Connecticut. 

b) Middle Atlantic: New York, New Jersey, and Pennsylvania. 

2) Midwest comprise East North Central and West North Central states. 

a) East North Central: Ohio, Indiana, Illinois, Michigan, and Wisconsin. 

b) West North Central: Minnesota, Iowa, Missouri, North Dakota, South Dakota, Nebraska, and Kansas. 

3) South comprises South Atlantic, East South Central and West South Central states. 

a) South Atlantic: Delaware, Maryland, District of Columbia, Virginia, West Virginia, North Carolina, South 

Carolina, Georgia, and Florida. 

b) East South Central: Kentucky, Tennessee, Alabama, and Mississippi. 

c) West South Central: Arkansas, Louisiana, Oklahoma, and Texas. 

4) West comprises Mountain and Pacific states. 

a) Mountain: Montana, Idaho, Wyoming, Colorado, New Mexico, Arizona, Utah, and Nevada. 

b) Pacific: Washington, Oregon, California, Alaska, and Hawaii

Source: U.S. Census Bureau 2012 Statistical Abstract 

http://www.census.gov/compendia/statab/cats/population.html
43 | Page

References

Hnatov, Matthew V., Non-Fire Carbon Monoxide Deaths Associated with the Use of Consumer 

Products 2008 Annual Estimates. Washington, D.C.: U.S. Consumer Product Safety 

Commission. 2011. <http://www.cpsc.gov/library/foia/foia11/os/co10.pdf >

Hnatov, Matthew V., Incidents, Deaths, and In-Depth Investigations Associated with Non-Fire 

Carbon Monoxide from Engine-Driven Generators and Other Engine-Driven Tools, 1999–2011. 

Washington, D.C.: U.S. Consumer Product Safety Commission. 2012.

http://www.cpsc.gov/library/foia/foia12/os/cogenerators.pdf.

Long, K., Saltzman, L. (1995). Non-fire Carbon Monoxide Incidents: Morbidity and Mortality

Related to the Use of Household Appliances. Washington, D.C.: U.S. Consumer Product Safety

Commission.

Mah, J., Non-Fire Carbon Monoxide Deaths Associated with the Use of Consumer Products 

1998 Annual Estimates. Washington, D.C.: U.S. Consumer Product Safety Commission. 2001.

<https://www.cpsc.gov/library/co98.pdf>

Vagts, S., Non-Fire Carbon Monoxide Deaths Associated with the Use of Consumer Products 

1999 and 2000 Annual Estimates. Washington, D.C.: U.S. Consumer Product Safety 

Commission. 2003.

<https://www.cpsc.gov/library/co03.pdf>

Vagts, S., Non-Fire Carbon Monoxide Deaths Associated with the Use of Consumer Products 

2001 Annual Estimates. Washington, D.C.: U.S. Consumer Product Safety Commission. 2004.

<https://www.cpsc.gov/library/co04.pdf>

U.S. Census Bureau. Statistical Abstract of the United States: 2012.

U.S. Census Bureau. American Factfinder. <http://factfinder.census.gov>

U.S. Department of Agriculture. Briefing Rooms: Measuring Rurality. 7 Nov. 2008

<http://www.ers.usda.gov/briefing/Rurality/>

University of Washington, WWAMI Rural Health Research Center. Rural-Urban Commuting 

Area Codes (version 2.0). 5 Jan. 2009 <http://depts.washington.edu/uwruca/>