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Non-mercury Thermometers

Did you know that many communities have exchange programs that will replace your old mercury filled thermometer with a safer non-mercury one free of charge?

Medical digital thermometer reading

Photo: wenzday01 (flickr)

In some places you can trade in your old mercury thermometer for a new spirit or digital thermometer like this one

Do you know that many communities offer medical thermometer exchange programs, and will replace your old mercury filled thermometer with a safer non-mercury one free of charge?

While mercury thermometers are safe when used correctly, they pose significant risks when they break or if disposed of improperly. Mercury is a highly toxic metal, and excessive exposure can cause serious health problems including neurological disorders.

How do the new safer thermometers work?

There are several types of accurate non-mercury thermometers for home use. Spirit thermometers use a non-toxic alcohol instead of mercury to register the temperature. Like liquid mercury, the alcohol expands in volume as it gets warmer, causing the liquid to move up the thin tube inside the glass thermometer.

Digital thermometers contain a device called a thermoresistor. The thermoresistor has an electrical current running through it, and the resistance, or how freely the current can flow, changes with temperature. A small computer or other circuit measures the resistance, and converts it to a temperature. The temperature is then displayed on the thermometer screen.

Want to find out about thermometer-exchange programs in your area?

Try calling your local health department or pharmacy to ask about local programs. However, even if your community doesn’t offer an exchange program, it is important to properly dispose of mercury-containing products. Mercury should never go in the regular household trash. Contact your local hazardous materials department to learn the right way to protect you and your environment from mercury contamination.

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