Film plates are the most common type of radiation dosimeter, using films and filters to detect radiation dose levels. They are not reusable, but they provide a permanent record of exposure. Optically stimulated luminescence (OSL) dosimeters use aluminum oxide to detect radiation dose levels. At UTHealth, two badges are used for most employees: Luxel by Landauer (aluminum oxide dosimeter) and TLD (thermoluminescent dosimeter).
The Luxel badge measures the total body dose of X-ray, gamma radiation and beta radiation. The TLD measures the dose in the extremities (fingers, hands, etc.). For more information on the proper procedure for using dosimetry, see the section titled 'How do I use my dosimeter?'.A radiation dosimeter is a device that measures the dose absorption of external ionizing radiation. It is used by the person being monitored when using it as a personal dosimeter and is a record of the radiation dose received.
Modern electronic personal dosimeters can provide a continuous reading of the cumulative dose and the current dose rate, and can warn the user with an audible alarm when a specified dose rate or cumulative dose is exceeded. Other dosimeters, such as thermoluminescent or film types, require post-use processing to reveal the cumulative dose received and cannot give a current dose indication while in use. Gas-filled detectors are among the most commonly used types of radiation detectors. There are several types of gas-filled detectors, and while they have several differences in their operation, they are all based on similar principles. When the gas in the detector contacts the radiation, it reacts, the gas ionizes and the resulting electronic charge is measured with a meter.
Additional dosimeters can be used to assess the dose in the extremities or in radiation fields that vary greatly depending on the orientation of the body towards the source. The dosimeter plays an important role within the international radiation protection system developed by the International Commission on Radiological Protection and the International Commission on Radiation Units and Measures. These dosimeters can be read immediately instead of having to send them to a laboratory for processing. The dosimeter is located on or adjacent to the items that are irradiated during the process as a validation of the received dose levels. It is not really a direct dosimeter, because there is no a priori way of knowing the calibration constant in units of ferric ion molecules produced per unit of absorbed dose. However, in order for the Radiation Safety Program to implement any control measures or dosimetry for monitoring, pregnancy must be reported in writing to the Radiation Safety Program.
This is an actual reading obtained from, for example, an ambient dose gamma monitor or a personal dosimeter. For dosimetry, lithium fluoride (LiF) with certain impurities is usually used as base material; these impurities determine its properties in detail. Radiation dosimetry is widely used by medical personnel, workers in nuclear industry and many other workers exposed for work reasons around the world. They can also be given to short-term visitors for whom monthly (or quarterly) dosimeters don't make sense and to pregnant staff to avoid exposure to an unexpected source of activity. The vitamin D dosimeter indicates photoisomerization of provitamin D3 to pre-vitamin D3, which is an initial step in cutaneous vitamin D3 synthesis. Manufacturing processes that treat products with ionizing radiation, such as food irradiation, use dosimeters to calibrate doses deposited on matter being irradiated.
The electronic personal dosimeter is an electronic device that has several sophisticated functions such as continuous monitoring which allows alarm warnings at preset levels and live reading of accumulated dose. Dosimetric accuracy of 5-10% is generally considered necessary for effective control of sterilization process.
