The ALARA principle is based on which model?

The ALARA principle, which stands for "As Low As Reasonably Achievable," is grounded in the linear no-threshold (LNT) model of radiation exposure. This model posits that any amount of ionizing radiation has the potential to cause a biological effect, and thus, there is no safe threshold that can be defined.

The LNT model is particularly significant in the context of radiation safety because it emphasizes minimizing exposure to ionizing radiation as much as possible. Understanding that even minimal exposure carries some risk reinforces the commitment to uphold the ALARA principle, guiding professionals to adopt practices that reduce radiation dose to patients and staff while still achieving necessary diagnostic or therapeutic objectives.

In contrast, the threshold model suggests that there is a level of exposure below which there would be no significant risk of harmful effects, which does not align with the essence of the ALARA principle. Non-linear models and incremental models also do not provide the basis for understanding the rationale behind ALARA, as they differ in their assumptions about the relationship between dose and effect.