Film Badge (Dosimeter)
- Film badge dosimeters are small portable devices used to monitor cumulative radiation dose due to ionizing radiation.
- The device consists of two parts: photographic film and a holder.
- The film emulsion is black and white photographic film with varying grain size to affect its sensitivity to incident radiation.
- The ionisation effect by the radioactive rays will decompose silver bromide crystal on the film.
- All the α-particle, β-particle and γ-ray can be detected by a photograph film.
- Films are kept in the badges worn by workers as a tracer device of radioactive rays.
Advantages
- The major advantages of using a film badge dosimeter to detect radioactivity are that it provides a permanent record,
- It can measure doses due to different types of radiation.
Disadvantages
- The main disadvantage of using a film badge dosimeter is that it usually cannot be read on site and must be sent to be processed in order to prove the presence of radioactive rays).
- The film dosimeters are for one-time use only and cannot be reused.