Typical annual background radiation levels in the Las Cruces area are near 150 mrem per year, well above the normal occupational exposure level of NMSU employees. This accounts for the fact that energy deposited in one organ is not as damaging as a uniform whole-body dose. Many individuals working with radiation sources receive doses that are not appreciably above background for personnel monitoring devices. A silver halide emulsion is spread on a support base and radiation interacting in the emulsion darkens the film. As with any other film, care should be taken to protect film dosimeters from extreme heat and moisture.
Radiographers commonly utilize film badges as personnel monitors for x-ray exposure.
Interactions in the material elevate electrons into high energy traps in the lattice structure. They remain there until the material is heated to high temperatures. When liberated from their traps, the electrons give up their excess energy by emitting light. The quantity of light output is proportional to the amount of radiation that interacted in the device. This type of dosimeter should be protected from the effects of heat and moisture.