Dosimeters contain phosphor crystals that trap electrons freed by various forms of harmful radiation; worn over the course of one to three months, these crystals can then be used to determine radiation exposure through a process known as dosimetry.

What is a dosimeter and how does it work?

A radiation dosimeter or badge does not provide protection but detects and measures radiation that you have been exposed to. The badge will detect high-energy beta, gamma or x-ray radiation. Dosimeters cannot detect low energy beta radiation from some isotopes, including carbon-14, tritium or sulfur-35.

How does a dosimeter measure exposure to radioactivity?

A thermoluminescent dosimeter measures ionizing radiation exposure by measuring the intensity of light emitted from a Dy or B doped crystal in the detector when heated. The intensity of light emitted is dependent upon the radiation exposure.