Thermostats

Mercury thermostats use mercury tilt switches to sense and control room temperature through communication with heating, ventilating, and air conditioning (HVAC) equipment. A mercury thermostat may contain one or more switches, depending on how many heating and cooling systems it activates.

The Northeast Waste Management Officials' Association (NEWMOA), provides a fact sheet with information on the use of mercury in thermostats, including the amount of mercury used in thermostats in the US, non-mercury alternatives, and collection and recycling programs.

Mercury thermostats are unlikely to break or leak mercury while is use, but they need to be properly disposed of when being replaced. If a mercury thermostat is being replaced by a household occupant rather than by a heating and air conditioning professional, the old thermostat should be disposed of by taking it to a state or local household hazardous waste collection center for recycling. For information about these programs, contact your local collection program to find out whether you can drop your old thermostats off any time or whether you should wait for the next collection effort in your area. You can also use earth911.com to find collection programs in your area -- just type in "thermostat" or "mercury" and your zip code to get a list of programs that accept mercury-containing thermostats.