Preventing Carbon 

Monoxide Poisoning

Information for Older Adults and 

Their Caregivers

January 2009

Do you know that 

carbon monoxide 

(CO) is the most 

common cause of 

poisoning death in the United 

States? Unintentional CO 

poisonings are responsible for 

about 500 deaths and 15,000 

visits to emergency rooms 

annually. Older adults over 

65 years of age are especially 

vulnerable to unintentional 

CO poisoning due to their 

high frequency of pre-existing 

medical conditions.1 While CO 

alarms can save lives, fewer 

than one third of American 

homes have them installed.2

What Is Carbon 

Monoxide (CO)?

CO is an odorless, colorless 

gas that can cause illness and 

death. It is produced whenever 

any fuel such as natural gas, 

propane, gasoline, oil, kerosene, 

wood or charcoal is burned. 

Devices that produce CO include 

cars, boats, gasoline engines, 

stoves and heating systems. CO 

from these sources can build up 

in enclosed or semi-enclosed 

spaces. When people inhale 

CO, the toxic gas enters the 

bloodstream and blocks oxygen 

from being absorbed into the 

body, which can damage tissues 

and result in death.3

What Are the 

Symptoms of CO 

Poisoning?

For most people, the first 

signs of exposure to low 

concentrations of CO 

include mild headache and 

breathlessness upon moderate 

exercise. Continued or acute 

exposure can lead to flu-like 

symptoms including more 

severe headaches, dizziness, 

tiredness, nausea, confusion, 

irritability, and impaired 

judgment, memory and 

coordination.4 CO is called the 

“silent killer” because if these 

early signs are ignored, a person 

may lose consciousness and be 

unable to escape the danger. 

You May Be Symptom 

Free and Still Exposed 

to Unsafe CO Levels

Breathing low concentrations of 

CO may not result in obvious 

symptoms of CO poisoning, 

yet exposure to low levels 

of CO can cause long-term 

health damage, even after the 

Fact Sheet

Everyone is at 

risk of being 

poisoned by carbon 

monoxide exposure. 

Older adults 

with pre-existing 

conditions, such 

as chronic heart 

disease, anemia, 

or respiratory 

problems, are even 

more susceptible 

to the effects of this 

odorless, colorless 

gas.
CO source is removed. These health effects 

include long-term neurological damage such as 

learning and memory impairments, emotional 

and personality effects, and sensory and motor 

disorders.5

Who Is at Risk from CO 

Poisoning?

People of all ages are at risk for CO poisoning. 

Persons living with chronic heart disease, 

anemia, or respiratory problems are more 

susceptible to its effects.6 Older adults more 

frequently have these pre-existing conditions, 

which lower their tolerance and increase the 

risk of a fatal exposure.7 CO poisoning can 

also be highly dangerous for unborn children, 

greatly increasing the risk of fetal death and 

developmental disorders.8, 9

More Common among Minorities

A study conducted in Washington State among 

minority populations showed that Hispanic 

populations had a four times greater risk and 

black populations had a three times greater 

risk than white populations for CO poisoning. 

The most common source of CO poisoning 

among those populations was burning charcoal 

briquettes. Approximately 66% of Hispanic 

victims and 40% of black victims became 

poisoned as a result of indoor burning of 

charcoal briquettes.10

If You Experience Symptoms 

You Think Could Be from CO 

Poisoning:

n Get fresh air immediately. Open doors and 

windows and turn off stoves, ovens, heaters 

and similar appliances and leave the house.

n Call a poison center immediately at 1-800-

222-1222. The poison experts there will let 

you know if you need to seek further medical 

attention. 

To Prevent CO Poisoning,

Remember I CAN B:

n Install CO alarms near sleeping areas.

n Check heating systems and fuel-burning 

appliances annually.

n Avoid the use of non-vented combustion 

appliances. 

n Never burn fuels indoors except in devices 

such as stoves or furnaces that are made for 

safe use.

n Be Attentive to possible symptoms of CO 

poisoning.

Other Tips for Preventing CO 

Poisoning:

n Keep gas appliances properly adjusted.

n Consider purchasing a vented space heater 

when replacing a non-vented one. 

n Use proper fuel in kerosene space heaters.

n Install and use an exhaust fan vented to the 

outdoors over gas stoves.

n Open flues when using the fireplace.

n Choose properly-sized wood stoves that are 

certified to meet EPA emission standards. 

Ensure wood stove doors fit tightly.

n Have your heating system and chimney 

inspected and cleaned by a qualified 

technician annually.

Red 

Blood 

Cell

Oxygen

(vital to life)

Oxygen

Oxygen

Carbon

Monoxide

(deadly fumes)
n Make sure all interior fuel-burning appliances 

are in good condition and have proper 

ventilation.

n Never idle the car in the garage, even if the 

garage door is open to the outside.

n Use portable generators outside and far 

away from buildings. Never use portable 

generators on balconies or near doors, vents 

or windows. Never use portable generators 

near to where you sleep or your family 

sleeps.

n Never use a charcoal grill indoors, even in a 

fireplace.

n Propane heaters or heaters using other 

fuels placed in enclosed hunting and fishing 

shanties, should be vented to the outside.

n Never heat your home with a gas oven. 

CO Alarms

Half of all unintentional CO poisoning deaths 

could be prevented with the use of CO alarms. 

Alarms should be Underwriters Laboratories 

(UL) approved and are generally available at 

local hardware stores.11 The cost is minimal 

and in view of the possibility that it may save 

the lives of you and your family it is a bargain. 

Install a CO alarm on every floor of your home 

and within hearing range of each sleeping area. 

Carefully follow manufacturers’ instructions for 

their placement, use, and maintenance. Unlike 

smoke alarms, CO alarms may expire after 

several years. 

Carbon Monoxide Alarms

electric plug-in

battery operated 

wall/ceiling unit

Don’t let buying a CO alarm lull you into a 

false sense of security. CO alarms should only 

be considered a back-up for proper use and 

maintenance of your fuel-burning appliances. 

CO alarms are not designed for low-level CO 

monitoring and there have been questions 

about whether CO alarm standards are 

protective enough, especially for sensitive groups 

such as older adults.13

How to Tell the Difference 

between CO Poisoning 

and the Flu

Since many of the symptoms of 

CO poisoning are similar to those 

of the flu, you may not think that 

CO poisoning could be the cause. 

Symptoms could be the result of 

CO poisoning when:

n You feel better when you are 

away from your home.

n More than one person in the home 

gets sick at the same time (it 

usually takes several days for the 

flu to pass from person to person).

n Family members who are most 

affected spend the most time in 

the home.

n Symptoms occur or get worse 

shortly after turning on a fuelburning device or running a vehicle 

in an attached garage.

n Indoor pets also appear ill, 

exhibiting symptoms such as 

drowsiness and lethargy (human 

flu viruses are not transmitted to 

pets).

n Generalized aching, low-grade 

fever, or swollen lymph nodes 

(these are typical of a cold 

or flu).12
Aging Adults and Environmental 

Health Issues

EPA’s Aging Initiative is working to protect the 

health of older adults from environmental 

hazards through risk management and 

prevention strategies, education and research. 

For more information about EPA’s Aging 

Initiative, visit www.epa.gov/aging

Printed copies of this fact sheet can be ordered 

at: http://www.epa.gov/aging/resources/

factsheets/order.htm

Additional Resources

Your Local Poison Center

n 1-800-222-1222 

n Internet: www.aapcc.org 

U.S. Environmental Protection Agency

Carbon Monoxide

http://www.epa.gov/iaq/co.html 

CDC

Carbon Monoxide

http://www.cdc.gov/co/ 

Consumer Product Safety Commission

Home Heating Equipment Safety

www.cpsc.gov/cpscpub/pubs/heatpubs.html 

Carbon Monoxide Alarms

www.cpsc.gov/cpscpub/prerel/

prhtml01/01069.html 

Portable Generators

www.cpsc.gov/cpscpub/pubs/portgen.html

Endnotes

1 Centers for Disease Control and Policy. Carbon 

Monoxide-Related Deaths – United States, 1999-2004. 

Morbidity and Mortality Weekly Report. December 21, 2007; 

56(50):1309-12.

2 Home Safety Council. Unintentional Home Injury in the 

United States. State of Home Safety: 2004 Edition. http://

www.homesafetycouncil.org./state_of_home_safety/

sohs_2004_p017.pdf. 

3 (CDC), National Center for Environmental Health, 

“Carbon Monoxide Poisoning: Questions and Answers,” July 

2006. http://www.cdc.gov/co/faqs.htm 

4 The U.S. Environmental Protection Agency (EPA), Indoor 

Environments Division (6607J) Office of Air and Radiation, 

“Protect Your Family and Yourself from Carbon Monoxide 

Poisoning,” October 1996. http://www.epa.gov/iaq/pubs/

coftsht.html

5 Delayed Neuropathology after Carbon Monoxide 

Poisoning Is Immune-Mediated, Stephen R. Thom, Veena 

M. Bhopale, Donald Fisher, Jie Zhang, Phyllis Gimotty and 

Robert E. Forster, Proceedings of the National Academy of 

Sciences of the United States of America, Vol. 101, No. 37 

(Sep. 14, 2004), pp. 13660-13665. 

EPA. 2000. Air Quality Criteria for Carbon Monoxide. 

U.S.EPA, National Center for Environmental Assessment. 

June, 2000. EPA 600/P-99/001F. 

6 Centers for Disease Control and Prevention (CDC), 

National Center for Environmental Health, “Carbon 

Monoxide Poisoning: Questions and Answers,” July 2006. 

http://www.cdc.gov/co/faqs.htm 

7 CPSC. 2004. Non-Fire Carbon Monoxide Deaths 

Associated with the Use of Consumer Products: 2001 

Annual Estimates. U.S. Consumer Product Safety 

Commission, Division of Hazard Analysis, May 13, 2004. 

8 Raub, J. A., M. MathieuNolf, N. B. Hampson, and S. 

R. Thom. Carbon Monoxide Poisoning - a Public Health 

Perspective. TOXICOLOGY (145):1-14, (2000).)

9 Liu, S. Krewski, D., Shi, Y, Chen, Y, and R.T. Burnett. 

2003. Association between gaseous ambient air pollutants 

and adverse pregnancy outcomes in Vancouver, Canada. 

Environmental Health Perspectives. 111:1773-1778.

10 Ralston, J.D. and N.B. Hampson. 2000. Incidence of 

severe unintentional carbon monoxide poisoning differs 

across racial/ethnic categories. Public Health Reports. 

115:46-51. U.S. Department of Health and Human Services. 

11 Yoon, S., Macdonald, S., Parrish, G. 1998. Deaths from 

unintentional carbon monoxide poisoning and potential for 

prevention with carbon monoxide detectors. JAMA. 279(9): 

685-687

12 U.S. Department of Housing and Urban Development. 

Healthy Homes Issues: Carbon Monoxide, Healthy homes 

Initiative Background Information, December 2005. http://

www.healthyhomestraining.org/Documents/HUD/HUD_CO_

Brief.pdf .

13 The Minnesota Department of Health, Environmental 

Health Services Division, “Carbon Monoxide (CO) Poisoning 

In Your Home,” April 2007. http://www.health.state.mn.us/

divs/eh/indoorair/co/index.html

Publication Number EPA 100-F-09-001