On Nov. 1, 2004, a New York City local law went into effect requiring the installation of carbon monoxide (CO) detectors in all residential units. The law applies to one- and two-family homes, apartment houses (three-family homes and above), hotels, motels, lodging houses, rooming houses, dormitories, rectories, convents and group homes. As winter approaches and people begin heating their homes, the risk for CO exposure greatly increases. Detectors are important -- and in some states and municipalities, now legally required -- safeguards against the danger of carbon monoxide poisoning. Several ANSI members and accredited standards developers offer standards that govern the use and testing of these life-saving instruments.

Carbon monoxide is an odorless, tasteless, colorless gas that is created when fuels (such as gasoline, wood, coal, natural gas, propane, oil, and methane) burn incompletely. It is produced by many common devices, including cars, gas appliances, and wood stoves. The poisonous gas can cause suffocation even at very low concentrations with its ability to retard the body's release of oxygen in the bloodstream. Concentrations as low as 20 or 30 parts per million (PPM) can be harmful if one is exposed for several hours. The symptoms associated with CO poisoning include headache, fatigue and nausea. Exposure at 2,000 PPM for one hour will cause unconsciousness.

Carbon monoxide detectors trigger an alarm based on the accumulation of CO over time. The New York City law requires the installation of a detector within 15 feet of the primary entrance to any room used for sleeping purposes in residential buildings that use fossil fuels -- coal, kerosene, oil, wood, gas and other petroleum products -- in a furnace, boiler, water heater or fireplace. The National Fire Protection Association (NFPA), an ANSI member and accredited standards developer, is currently updating the 2003 version of NFPA 720, Recommended Practice for the Installation of Household Carbon Monoxide (CO) Warning Equipment, which provides recommended practices for the selection, location, performance, and maintenance of equipment that detects hazardous concentrations of CO in family living units.