Let’s Talk Safety: Carbon Monoxide: A Silent Killer

This column addresses safety issues of interest to water and wastewater personnel, and will appear monthly in the magazine. The Journal is also interested in receiving any articles on the subject of safety that it can share with readers in the “Spotlight on Safety” column.

Carbon Monoxide: A Silent Killer

S Water gushing from a 30-inch pipe near the

University of California poured into Pauley

Pavilion, and six people helping clean up the flooded arena were treated for carbon monoxide exposure from generator exhaust. S Carbon monoxide leaking from a faulty flue pipe attached to a water heater killed the manager and sickened 27 others at a restaurant in New York. S Downed power lines from ice storms in the

Northeast and Midwest forced hundreds of thousands to spend the holidays without electricity, and carbon monoxide from gasoline-powered generators is blamed for eight deaths. S A 77-year-old man was found dead his home after leaving his car running in the garage.

These true stories are just a fraction of the deaths and illnesses reported every year from carbon monoxide (CO) poisoning. Exposure to CO can occur on the job, as well as in homes and buildings that are inadequately ventilated and lack the proper detection devices. People can be affected by CO poisoning using gasolinepowered tools, such as concrete cutting saws, high-pressure washers, floor buffers, welders, pumps, compressors, and generators.

An odorless, tasteless, colorless gas, CO is produced by the incomplete combustion of carbon-based fuels, such as gasoline, natural gas, fuel oil, charcoal, or wood. Because of the potential for CO poisoning, small gasoline-powered engines and tools present a serious health hazard when operated indoors or in an enclosed space. The CO can rapidly accumulate, even in areas that appear to be well-ventilated. Buildup can lead to dangerous or fatal concentrations within minutes. Opening doors and windows or operating fans does not guarantee safety.

Health Effects of Carbon Monoxide

The CO interferes with the delivery of oxygen in the blood to the rest of the body. When high concentrations of CO are inhaled, it can displace the oxygen in the bloodstream and cause one or more of the following symptoms: S Poor coordination S Confusion and disorientation S Fatigue S Nausea S Headache S Dizziness S Weakness S Visual disturbances S Changes in personality S Loss of consciousness

If the concentration is high enough and the exposure is long enough, CO exposure can lead to death. Approximately 1,000 people die each year as a result of CO poisoning, according to the Centers for Disease Control and Prevention (CDC).

Prevention Techniques

In the workplace, the CDC has the following recommendations to prevent CO poisoning: S Do not use or operate gasoline-powered

engines or tools inside buildings or in partially enclosed areas. S Learn to recognize the symptoms and signs of

CO overexposure. S Always place pumps, power units, and gasoline-powered compressors outdoors and away from air intakes so that engine exhaust is not drawn indoors where the work is being done. S Consider using tools powered by electricity or compressed air if they are available and can be used safely. S Use personal CO monitors where potential sources of CO exist. These monitors should be equipped with audible alarms to warn workers when CO concentrations are too high or when exceeding the National Institute for Occupational Safety and Health (NIOSH) ceiling limit for CO of 200 parts per million. S Conduct a workplace assessment to identify all potential sources of CO exposure. S Educate workers about the sources and conditions that may result in CO poisoning, as well as the symptoms and control of CO exposure. S Monitor employee CO exposure to determine the extent of the hazard. S Always use the proper fuel in a combustion device. S Don’t leave a motor vehicle or gasolinepowered lawn mower running in enclosed spaces, such as a garage or shed.

First Aid for Exposure

If you have any symptoms, or notice that a coworker is impaired, immediately turn off the equipment, go outdoors or to a place with uncontaminated air, and do the following: S Call 911 or another local emergency number for medical attention or assistance. Be sure and tell the first responder that you suspect

CO poisoning. S Stay away from the work area until tools are deactivated and measured CO concentrations meet accepted guidelines and standards. S Watch coworkers for the signs of CO toxicity. S If you are affected by CO, do not drive a motor vehicle—get someone else to drive you to a health care facility.

For more information go to the CDC fact sheet on CO at http://www.cdc.gov/co/pdfs/ flyer_danger.pdf. S