When you receive your badges, EHS will provide you with instructions for setting up this account. You can also request a summary of your monitoring badge results by calling EHS. It is not required that you view your dose report; however, this is the only way that you will routinely be notified about your dose results.
In the case of body badges, doses are reported as deep or shallow or as doses to the lens of the eye. Deep dose is due to penetrating radiations such as gamma rays or higher energy x-rays. Deep doses are applied against the whole body dose limit. Shallow dose is due to less penetrating radiations such as beta radiation and low energy x-rays.
Shallow doses are applied against the skin dose limit. Dose to the lens of the eyes is due to an intermediate range of radiations and energies and is applied against the lens of the eye dose limit. In the case of ring badges, dose is only reported as shallow dose and is applied against the extremities dose limit.
Doses are reported in millirems. The minimum reported dose for x-rays for body badges is 10 millirems for x-rays, and for ring badges is 20 millirems. If no dose is reported, the total dose received was less than the minimum reported dose. Contact EHS for a copy of your radiation exposure history. EHS maintains radiation exposure records indefinitely. If you terminate employment with the University, EHS will provide your radiation exposure history to you or your new employer upon request.
Source: www. Examples of filters: There is an open window that makes it possible for weaker radiations to reach the film. A thin plastic filter which attenuates beta radiation but passes all other radiations A thick plastic filter which passes all but the lowest energy photon radiation and absorbs all but the highest beta radiation.
A dural filter which progressively absorbs photon radiation at energies below 65 keV as well as beta radiation. A cadmium lead filter can be used for thermal neutrons detection. The capture of neutrons n,gamma reactions by cadmium produces gamma rays which blacken the film thus enabling assessment of exposure to neutrons. Advantages and Disadvantages of Film Dosimeters Advantages of Film Dosimeters A film badge as a personnel monitoring device are very simple and therefore they are not expensive.
A film badge provides a permanent record. Film badge dosimeters are very reliable. A film badge is used to measure and record radiation exposure due to gamma rays, X-rays and beta particles. Disadvantages of Film Dosimeters Film dosimeters usually cannot be read on site instead of they have to be sent away for developing. Film dosimeters are for one-time use only , they cannot be reused.
Exposures of less than 0. Radiation Dose Measuring and Monitoring In previous chapters, we described the equivalent dose and the effective dose.
The ambient dose equivalent is an operational quantity for area monitoring of strongly penetrating radiation. The directional dose equivalent is an operational quantity for area monitoring of weakly penetrating radiation. The operational quantities for individual monitoring are: Personal dose equivalent , H p 0. Personal dose equivalent , H p The H p 10 dose equivalent is an operational quantity for individual monitoring for the assessment of effective dose. According to ICRP, occupational exposure refers to all exposure incurred by workers in the course of their work, with the exception of excluded exposures and exposures from exempt activities involving radiation or exempt sources any medical exposure the normal local natural background radiation.
The following table summarizes dose limits for occupationally exposed workers and for the public: Table of dose limits for occupationally exposed workers and for the public. Source of data: ICRP, In most situations of occupational exposure the effective dose, E, can be derived from operational quantities using the following formula: Sievert — Unit of Equivalent Dose In radiation protection, the sievert is a derived unit of equivalent dose and effective dose.
Examples of Doses in Sieverts We must note that radiation is all around us. Radiation Protection: Knoll, Glenn F. ISBN Stabin, Michael G. Martin, James E. Department of Energy, Instrumantation and Control. June Nuclear and Reactor Physics: J. Lamarsh, Introduction to Nuclear Reactor Theory, 2nd ed.
Lamarsh, A. Baratta, Introduction to Nuclear Engineering, 3d ed. Glasstone, Sesonske. Photographic film goes darker when it absorbs radiation, just like it does when it absorbs visible light. The more radiation the film absorbs, the darker it is when it is developed. People who work with radiation wear film badges , which are checked regularly to monitor the levels of radiation absorbed. The diagram shows a typical radiation badge when it is closed and what the inside looks like when it is opened.
There is a lightproof packet of photographic film inside the badge. The more radiation this absorbs, the darker it becomes when it is developed.
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