FILM BADGE

Typical Number in Hospital: 200

Cost Bands: 1

References: 3

It is required that all personnel who work with ionizing radiations wear monitors to log their accumulated exposure to radiation. The most common form of monitoring is the film badge in which a piece of photographic negative is covered by a set of filters which shade the film from incident radiation. At regular intervals the badges are returned to the monitoring service for development of the films and reading of the radiation dose from the optical density (opacity) of the film. The effect of the filters on the developed films is to allow an assessment of the type of radiation involved. This may be separated into diagnostic X-rays, radiotherapy, neutrons, and beta rays. The films are often read on automated densitometers but must also be examined visually, since radioisotope contamination may expose small spots on the film which might be missed by the densitometer.

For each film badge wearer, it is usual to maintain a cumulative total of radiation exposure which can be compared with accepted limits for daily or annual exposure.

Thermoluminescent dosimetry (TLD) badge systems provide an alternative.