What does a film dosimeter measure?

A film dosimeter measures optical density (OD), which is a critical factor in assessing radiation exposure. When ionizing radiation interacts with the film material, it causes changes in the film's chemical composition, resulting in a darkening that can be quantified as optical density. This measurement reflects the amount of radiation that has traversed the film, allowing users to determine the exposure levels received over a specific period.

Optical density is useful because it provides a visual representation of the radiation dose, which can be interpreted and correlated with exposure levels based on calibration data. Accurate readings of optical density enable radiologic technologists and health physicists to monitor and manage radiation safety, ensuring that occupational and patient exposure levels remain within regulatory limits.

This understanding helps promote safe practices in environments where fluoroscopy and other radiological procedures are performed, ensuring that personnel and patients are not overly exposed to harmful doses of radiation.