Safety Measures

CO is odorless, colorless, and tasteless, and can cause harmful side effects if inhaled. It mixes with the air, so it's preferable to install CO alarms at knee level, which is roughly the height of a sleeping person's nose and mouth if you place a CO detector in a bedroom. 

According to the United States Environmental Protection Agency (EPA), carbon monoxide detectors should be placed about five feet above the floor or at eye level. Carbon monoxide is lighter than air and rises with warm air.

It also rises with warm air, so the United States Environmental Protection Agency (EPA) recommends placing a carbon monoxide detector on a wall about five feet above the floor or about eye level. You can put them on the ceiling, too.

• carbon monoxide (CO) detectors should be placed at least 5 feet above the floor or eye level. 

• They should also be placed on every level of your home.

• Upstairs: place a CO detector in the hallway adjacent to bedrooms. Not needed inside the bedrooms. (Outside of each bedroom or sleeping area)

• Downstairs: place a CO detector in dinning area not inside the kitchen.

• At least 15 feet away from gas-burning appliances, like fireplaces or stoves

• Away from fuel-burning appliances, humid areas like bathrooms, direct sunlight, and sources of blowing air like fans, vents, or open windows 

Optional:

• Inside an attached garage, at least 10 feet from the garage door leading to your home.

• However, you need to keep it away from the gas water heater and furnace in the garage if you do so.

is CO heavier than air? No, carbon monoxide (CO) is slightly lighter than air. It has a specific gravity of 0.9657, while normal air has a specific gravity of 1.0. This means that CO will float up towards the ceiling.