What are Dosimeters and Where are They Used?

Dosimeters are devices used to measure exposure to ionizing radiation. They are typically worn on the outside of clothing, with a full-body dosimeter placed on the chest or torso to represent the dose to the whole body. This location monitors the exposure of most vital organs and represents the bulk of body mass. Dosimeters benefit anyone working with or near radiation.

They allow people to track their personal exposure and also allow management to monitor staff exposure on a daily and cumulative basis. Everyone benefits from the use of a dosimeter, which gives employees peace of mind knowing that their employers care about the number of doses they may be exposed to, and also giving management the opportunity to re-educate or retrain staff if the dose for certain medical or dental procedures is too high. Dosimeters are used by researchers, maintenance personnel, and anyone else working in a potentially radioactive environment. Passive dosimeters and electronic personal dosimeters are often used together to complement each other.

An electronic personal dosimeter is a modern dosimeter, which can provide a continuous reading of the cumulative dose and the current dose rate, and can warn the person using it when a specified dose rate or cumulative dose is exceeded. A thermoluminescent dosimeter (TLD) is a passive radiation dosimeter that measures exposure to ionizing radiation by measuring the intensity of visible light emitted by a sensitive crystal in the detector when the glass is heated. Digital badges, such as the Instadose+ dosimeter, can detect and record exposure and the results are available almost immediately when the information is downloaded to a computer, smartphone or mobile device. To estimate effective doses, dosimeters should be used in a position of the body representative of your exposure, usually between the waist and neck, in front of the torso, in front of the radioactive source.

At the end of the month or quarter, dosimeters should be returned to Radiation Safety as soon as possible to expedite processing. The DIS dosimeter is based on the combination of an ion chamber and a non-volatile electronic charge storage element. Thermoluminescent dosimeters were invented in 1954 by Professor Farrington Daniels of the University of Wisconsin-Madison. Dosimeters contain phosphorus crystals that trap electrons released by various forms of harmful radiation; used over the course of one to three months, these crystals can be used to determine radiation exposure through a process known as dosimetry. A personal dosimeter is a dosimeter, which the person being monitored wears on the surface of the body and records the radiation dose received.

Dosimeters benefit anyone working with or near radiation, allowing people to track their personal exposure and also allowing management to monitor staff exposure on a daily and cumulative basis.