When shopping for a Carbon Monoxide detector, make sure it reads "Underwriters Laboratories" or UL listed.
Listed CO alarms must pass a number of performance tests that verify they operate reliably under a variety of conditions. This includes operating within specified response times when exposed to several different CO levels. The higher the concentration the quicker a unit must respond.
Make sure the alarm works: Push the test button on the detector every month to make sure it works, and change the batteries twice a year.
In addition, remember that an improperly installed gas water heater or other gas appliance can be the cause of unsafe levels of carbon monoxide in a home -- and can also lead to explosions.
All new gas appliances should be installed by a master plumber, who has specific qualifications. The Washington Suburban Sanitary Commission has jurisdiction over gas appliances in Maryland; WSSC requires a permit and inspection after a gas appliance is installed in Prince George's and Montgomery counties.
Did you know? Besides homes, CO alarms are available for boats and recreational vehicles. The Recreation Vehicle Industry Association requires CO alarms in motor homes and in trailers.