LET’S TALK SAFETY 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 to 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 gasolinepowered 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. According to the Centers for Disease Control and Prevention (CDC), each year several thousand American workers are killed outright from CO exposure, making the poisonous gas one of the most dangerous and widespread industrial hazards. More deaths are caused by CO than any other toxic agent except alcohol. At least another 10,000 workers suffer from the debilitating effects of highlevel exposure. Millions more are subject to low-level, long-term CO exposure, the effects of which are not well-defined.
The primary danger with CO is that it cannot be easily detected. It’s an odorless, tasteless, colorless gas produced by the incomplete combustion of carbon-based fuels, such as gasoline, natural gas, fuel oil, charcoal, or wood. Poisoning occurs entirely from inhalation of the toxic compound from the air. The poisonous gas consists of just two elements, carbon and oxygen, and mixes readily with air. When mixed with air, large quantities of CO can be highly flammable and explosive, but situations resulting in such high concentrations are rare. 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. Poisoning from CO has affected people using gasoline-powered tools, such as concrete cutting saws, high-pressure washers, floor buffers, welders, pumps, compressors, and generators. 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 enters the bloodstream through the lungs and combines with hemoglobin. Hemoglobin is the red pigment in the blood that carries oxygen. Although CO follows the same path as oxygen, the poisonous gas combines with hemoglobin 210 times faster than does oxygen. This means that even though there may be ample oxygen in the surrounding atmosphere, CO will get into the bloodstream first. When you inhale high concentrations of CO, it can displace the oxygen in your bloodstream and cause one or more of the following symptoms: S Poor coordination S Confusion and disorientation S Fatigue S Nausea S Headache
S S S S S
Dizziness Weakness Visual disturbances Changes in personality Loss of consciousness
High blood-level concentrations of the compound will prevent sufficient amounts of oxygen from reaching the heart and brain. This can lead to suffocation, capillary hemorrhaging, permanent damage of nerve tissues and brain cells, and, possibly, death. Workers with health problems, such as heart trouble, anemia, or respiratory ailments, which affect the flow of oxygen in the bloodstream, may be more readily endangered by CO exposure than workers without such conditions. Because CO is a byproduct of cigarette smoking, the gas may adversely affect smokers more quickly than nonsmokers. Exposure to CO can also contribute to pneumonia by allowing the entry of saliva or foreign matter into the respiratory tract.
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 gasolinepowered compressors outdoors and away from air intakes so that the engine exhaust is not drawn indoors where 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
The 2018 Let's Talk Safety is available from AWWA; visit www.awwa.org or call 800.926.7337. Get 40 percent off the list price or 10 percent off the member price by using promo code SAFETY17. The code is good for the 2018 Let's Talk Safety book, dual disc set, and book + CD set.
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March 2019 • Florida Water Resources Journal