What does MPD stand for?

• A. Maximum Permissible Dose
• B. Maximum Possible Dose
• C. Median Permissible Dose
• D. Medical Permissible Dose

Answer: (A)

MPD stands for Maximum Permissible Dose. This is the upper limit of radiation dose that a person may receive in a given period (usually per year) that is considered to pose negligible risk. In dental radiography safety, MPD helps ensure that workers’ exposures stay below regulatory limits and guides the use of shielding, proper technique, and justification of each radiographic exposure to avoid crossing that limit. When doses approach MPD, protective measures are intensified and alternative, lower-dose imaging options are considered. The other terms aren’t standard in radiation safety practice—Maximum Possible Dose, Median Permissible Dose, and Medical Permissible Dose are not used to describe regulatory exposure limits.