Are Tritium Watches Hazardous?

Tritium is a radioactive form of hydrogen that occurs naturally in the environment. It emits a weak beta ray sufficient to produce luminescence. Because the beta ray has so little energy, there is little danger of toxicity.

Radium and Strontium

• Older watches with luminescent numerals were made with paints containing radium-226 or strontium-90. These are more hazardous radionuclides. A radionuclide is a man-made or natural element that emits radiation in the form of alpha or beta particles, or gamma rays. A Geiger counter is required to test a watch for radium or strontium. Alternatively, take your watch to a radiation-safety office for testing.

Plastic Watches

• In 1994, an article in British medical journal "The Lancet" raised fears about tritium toxicity from plastic watches. At the time, Swatch was the only known company using tritium in plastic watches. The medical research showed that tritium was absorbed through skin contact with the back of the watch. Swatch stopped using tritium in 1993, and subsequent research showed that the levels absorbed are significantly less than through natural environmental exposure to tritium.

Considerations

• Smith & Wesson and Luminox are the main watch brands that use tritium. The tritium is sealed in water- and oil-resistant airtight vials containing a minute quantity of the substance. According to Radiation Information Network, the quantities are completely safe and cannot penetrate skin, even if the vial is broken.