Carbon monoxide (CO) is a gas that poses a significant hazard because it is colorless, odorless, and tasteless, making it undetectable by human senses. This highly toxic gas forms from incomplete combustion of fuels like wood, natural gas, propane, or gasoline. A common question is whether it sinks or rises in the air. Understanding its behavior indoors is essential for effective safety.
Carbon Monoxide’s Behavior in Air
Carbon monoxide’s molecular weight is approximately 28.01 grams per mole (g/mol). Air, a mixture of gases, has an average molecular weight of about 28.97 g/mol. Because these molecular weights are very close, carbon monoxide does not significantly sink or rise. Instead, it mixes relatively evenly throughout an enclosed space.
This mixing property means CO does not layer at the ceiling or accumulate solely on the floor. Factors such as air currents from heating and cooling systems, opening and closing doors, and temperature differences greatly influence its distribution. Consequently, CO can be present at dangerous levels at any height within a room, making its uniform dispersal critical for safety.
Implications for Detector Placement
The mixing behavior of carbon monoxide directly impacts CO detector placement. Since the gas disperses throughout the air, detectors can effectively sense its presence at various heights. Always follow the manufacturer’s instructions for placement, as these are based on specific testing and design.
General guidance, often from organizations like the National Fire Protection Association (NFPA), recommends installing CO alarms in a central location outside each separate sleeping area and on every level of the home, including the basement. These locations ensure occupants are alerted quickly, especially during sleep. Placing detectors near bedrooms helps wake individuals before CO levels become dangerous. Having detectors on multiple levels accounts for varying air movement and potential CO sources in multi-story dwellings.
Ensuring Your Home’s Safety from Carbon Monoxide
Protecting a home from carbon monoxide involves understanding potential sources and implementing preventative measures. Common CO sources include fuel-burning appliances such as furnaces, water heaters, gas stoves, and fireplaces. Vehicle exhaust from an attached garage can also introduce CO into living spaces.
Proper ventilation is crucial when using any fuel-burning appliance. Regular professional inspection and maintenance of heating systems, chimneys, and other fuel-burning equipment are important steps to prevent CO leaks. Generators, charcoal grills, and other outdoor fuel-burning equipment must never be used indoors or in poorly ventilated areas, even with open windows, as they can rapidly produce lethal levels of carbon monoxide. If a carbon monoxide alarm sounds, immediately evacuate all occupants and pets outdoors and call emergency services. Do not re-enter until emergency responders confirm it is safe.