Mercury in ThermostatsThe cover has been removed from this rectangular model to show the four mercury-containing ampoules it contains.

Modern electronic thermostats save money through efficiency and do not contain mercury. However, replacing old thermostats can cause hazards.

Older electric thermostats often contain mercury. Circular gauge-type thermostats and rectangular models with lever-type adjustments often have mercury switches inside. Carefully lifting off the cover will reveal a glass ampoule of mercury.

The Statewide Mercury Thermostat Recycling Program offers ways to turn in old thermostats at no charge for licensed electricians and for do-it-yourselfers.

Mercury Toxicity and Health page leads to the latest information on how Mercury damages the brain, kidneys, liver and heart. Thermostat disposal and breakage, as well as building fires, can lead to exposures and contamination.

Mercury Education and Reduction Act (MERA) is a 2003 law allows mercury-containing thermostats in Washington only from manufacturers that participate in a recognized recovery/ recycling program.

Thermostat Recycling Corporation, run by the National Association of Electrical Contractors, supports recycling efforts in Washington State.

Related information

Interstate Mercury Education and Reduction Clearinghouse (IMERC) is a multi-state initiative. Washington is a member.

Mercury Use in Thermostats is a fact sheet from Interstate Mercury Education & Reduction Clearinghouse (IMERC)

Mercury-containing Thermostats Recycled shows the number of thermostats collected from HVAC contractors and the pounds of mercury represented.

Residents of Washington state call 1-800-RECYCLE or click the link for locations.