A dosimeter is an instrument used to measure ionizing radiation exposure in a science called dosimetry. It is an essential tool for people who work in situations where they are exposed to radiation, and it is used to ensure that a harmful dose of radiation is not received over a given period of time. Dosimeters are typically worn on the outside of clothing, and a "whole body" dosimeter is worn on the chest or torso to represent the dose to the whole body. Additional dosimeters can be worn to assess dose to extremities or in radiation fields that vary considerably depending on the orientation of the body to the source. There are different types of dosimeters, including:
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Electronic personal dosimeter: This is the most commonly used type of dosimeter, and it is an electronic device that has a number of sophisticated functions, such as continual monitoring which allows alarm warnings at preset levels and live readout of dose accumulated. These are especially useful in high dose areas where residence time of the wearer is limited due to dose constraints.
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Thermoluminescent dosimeter: This 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.
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Film badge: This is the most common type of radiation dosimeter, and it uses film and filters to detect radiation.
Dosimeters are important tools for maintaining occupational dose as low as reasonably achievable (ALARA) and ensuring worker safety. They benefit anyone working with or around radiation, allowing individuals to track their personal exposure and management to monitor the exposure of staff on a daily and cumulative basis.
