Monday, January 8, 2007

Carbon Monoxide General Information

Carbon monoxide is an odorless, colorless and toxic gas. Because it is impossible to see, taste or smell the toxic fumes, CO can kill you before you are aware it is in your home. At lower levels of exposure, CO causes mild effects that are often mistaken for the flu. These symptoms include headaches, dizziness, disorientation, nausea and fatigue. The effects of CO exposure can vary greatly from person to person depending on age, overall health and the concentration and length of exposure.

Definition
Carbon monoxide (CO) is a colorless, practically odorless, and tasteless gas or liquid. It results from incomplete oxidation of carbon in combustion. Burns with a violet flame. Slightly soluble in water; soluble in alcohol and benzene. Specific gravity 0.96716; boiling point -190oC; solidification point -207oC; specific volume 13.8 cu. ft./lb. (70oF). Auto ignition temperature (liquid) 1128oF. Classed as an inorganic compound.Source: "The Condensed Chemical Dictionary," 9th ed., revised by Gessner G. Hawley, Van Nostrand Reinhold Co., NY, 1977.

Sources of Carbon Monoxide
Unvented kerosene and gas space heaters; leaking chimneys and furnaces; back-drafting from furnaces, gas water heaters, wood stoves, and fireplaces; gas stoves; generators and other gasoline powered equipment; automobile exhaust from attached garages; and tobacco smoke. Incomplete oxidation during combustion in gas ranges and unvented gas or kerosene heaters may cause high concentrations of CO in indoor air. Worn or poorly adjusted and maintained combustion devices (e.g., boilers, furnaces) can be significant sources, or if the flue is improperly sized, blocked, disconnected, or is leaking. Auto, truck, or bus exhaust from attached garages, nearby roads, or parking areas can also be a source.

Health Effects Associated with Carbon Monoxide
At low concentrations, fatigue in healthy people and chest pain in people with heart disease. At higher concentrations, impaired vision and coordination; headaches; dizziness; confusion; nausea. Can cause flu-like symptoms that clear up after leaving home. Fatal at very high concentrations. Acute effects are due to the formation of carboxyhemoglobin in the blood, which inhibits oxygen intake. At moderate concentrations, angina, impaired vision, and reduced brain function may result. At higher concentrations, CO exposure can be fatal.

Levels in Homes
Average levels in homes without gas stoves vary from 0.5 to 5 parts per million (ppm). Levels near properly adjusted gas stoves are often 5 to 15 ppm and those near poorly adjusted stoves may be 30 ppm or higher.

Steps to Reduce Exposure to Carbon Monoxide
It is most important to be sure combustion equipment is maintained and properly adjusted. Vehicular use should be carefully managed adjacent to buildings and in vocational programs. Additional ventilation can be used as a temporary measure when high levels of CO are expected for short periods of time.
Keep gas appliances properly adjusted.
Consider purchasing a vented space heater when replacing an unvented one.
Use proper fuel in kerosene space heaters.
Install and use an exhaust fan vented to outdoors over gas stoves.
Open flues when fireplaces are in use.
Choose properly sized wood stoves that are certified to meet EPA emission standards. Make certain that doors on all wood stoves fit tightly.
Have a trained professional inspect, clean, and tune-up central heating system (furnaces, flues, and chimneys) annually. Repair any leaks promptly.
Do not idle the car inside garage.

Measurement Methods
Some relatively high-cost infrared radiation adsorption and electrochemical instruments do exist. Moderately priced real-time measuring devices are also available. The Pocket CO is a nanoelectronic carbon monoxide detecting instrument that has an 85 decibel alarm at 2 feet, a vibrating alarm, and LED warning of toxic gas. With a weight of less than 2 ounces it is the smallest known loud alarm detector/dosimeter presently available. The applications range from Emergency responders, industrial occupational safety to personal use. To view specs or make inquires visit www.transducertech.com. Product availability is the first quarter of 2007.

Standards or Guidelines
No standards for CO have been agreed upon for indoor air. The U.S. National Ambient Air Quality Standards for outdoor air are 9 ppm (40,000 micrograms per meter cubed) for 8 hours, and 35 ppm for 1 hour.

Additional Resources
To report a dangerous product or a product-related injury, call the Consumer Product Safety Commission's (CPSC) hotline at (800) 638-2772 or CPSC teletypewriter at (800) 638-8270. Consumer can obtain recall information at CPSC's web site - http://www.cpsc.gov/ Consumers can report product hazards to info@cpsc.gov

Links to Additional Information
EPA's Office of Air and Radiation page - "CO - How Carbon Monoxide Affects the Way We Live and Breathe"

EPA's Office of Research and Development:
Carbon Monoxide and the Nervous System. Raub, J. A., and V. A. Benignus. Carbon Monoxide and the Nervous System. NEUROSCIENCE AND BIOBEHAVIORAL REVIEWS 26(8):925-940, (2002).

Carbon Monoxide Poisoining - A Public Health Perspective. Raub, J. A., M. Mathieunolf, N. B. Hampson, and S. R. Thom. Carbon Monoxide Poinsoning--a Public Health Perspective. TOXICOLOGY (145):1-14, (2000).

Revised Evaluation of Health Effects Associated With Carbon Monoxide Exposure: An Addendum to the 1979 EPA Air Quality Criteria Document for Carbon Monoxide Benignus, V., L. Grant, D. Mckee, and J. Raub. Revised Evaluation of Health Effects Associated With Carbon Monoxide Exposure: An Addendum to the 1979 EPA Air Quality Criteria Document for Carbon Monoxide. U.S. Environmental Protection Agency, Washington, D.C., EPA/600/8-83/033F (NTIS PB85103471).

Centers for Disease Control and Prevention (CDC)National Center for Environmental Health
Carbon Monoxide Poisoning Fact Sheet - (offered in many languages) - www.cdc.gov/co/faqs.htm

U.S. Consumer Product Safety Commission (CPSC)Office of Information and Public AffairsWashington, D.C. 20207www.cpsc.gov

CPSC protects the public from the unreasonable risk of injury or death from 15,000 types of consumer products under the agency's jurisdiction. To report a dangerous product or a product-related injury, you can go to CPSC's forms page - www.cpsc.gov/talk.html and use the first on-line form on that page. Or, you can call CPSC's hotline at (800) 638-2772 or CPSC's teletypewriter at (800) 638-8270, or send the information to info@cpsc.gov.

Carbon Monoxide Questions and Answers (CPSC document #466)

"Your Home Fire Safety Checklist" - www.cpsc.gov/cpscpub/pubs/556.html - CPSC document #556

Surviving the Aftermath of Hurricane Katrina CPSC Warns of Deadly Post-Storm Dangers with Portable Generators, Candles and Wet Appliances - www.cpsc.gov/CPSCPUB/PREREL/prhtml05/05251.html August 31, 2005, CPSC Release #05-251

U.S. Department of Homeland SecurityU.S. Fire Administration, 16825 S. Seton Ave., Emmitsburg, MD 21727Voice: (301) 447-1000 Fax: (301) 447-1346 Admissions Fax: (301) 447-1441www.usfa.fema.gov

Carbon Monoxide page - www.usfa.fema.gov/safety/co/

Exposing an Invisible Killer: The Dangers of Carbon Monoxide - www.usfa.fema.gov/safety/co/fswy17.shtm

American Lung Associationwww.lungusa.org

Fact Sheet on Carbon Monoxide - www.lungusa.org/air/carbon_factsheet99.html

Occupational Safety and Health Administrationwww.osha.gov

Fact Sheet on Carbon Monoxide - www.osha.gov/OshDoc/data_General_Facts/carbonmonoxide-factsheet.pdf

U.S. National Library of Medicine and the National Institute of Health
"Carbon Monoxide Poisoning" www.nlm.nih.gov/medlineplus/carbonmonoxidepoisoning.html

About Carbon Monoxide Detectors
CPSC Recommends Carbon Monoxide Alarm for Every Home (January 18, 2001 CPSC Release # 01-069)
The U.S. Consumer Product Safety Commission (CPSC) recommends that every home should have a carbon monoxide (CO) alarm. CPSC also urges consumers to have a professional inspection of all fuel- burning appliances -- including furnaces, stoves, fireplaces, clothes dryers, water heaters, and space heaters -- to detect deadly carbon monoxide leaks. CPSC recommends that every home should have at least one CO alarm that meets the requirements of the most recent Underwriters Laboratories (UL) 2034 standard or International Approval Services 6-96 standard. www.cpsc.gov/cpscpub/prerel/prhtml01/01069.html

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