In addition to establishing an upper limit on a person's permissible radiation exposure, regulations also require that licensees maintain a program to keep occupational exposures As Low As Reasonably Achievable (ALARA). This means that every activity involving exposure to radiation should be planned so as to minimize unnecessary exposure to individual workers and the worker population.
An ALARA program has been incorporated as part of the University’s Radiation Safety Program. It outlines the responsibilities for the use of radioactive materials and ionizing radiation producing equipment:
- The Radiation Worker shall review clinical and experimental procedures with the objective of reducing unnecessary exposures.
- The Authorized User shall ensure that personnel are properly trained and shall consult with the RSO with regard to keeping exposures ALARA.
- The Radiation Safety Office shall foster a culture for safety, review authorized users’ procedures and physical layouts, and investigate radiation exposures that exceed ALARA investigation levels.
- The University Radiation Safety Committee shall review occupational radiation exposures that exceed ALARA investigation levels and shall prompt corrective actions as deemed necessary.
Throughout the calendar year, annual cumulated exposure is routinely evaluated by the Radiation Safety Office, and action is taken at the following levels:
|Regulatory limit||Level I Investigation||Level 2 Investigation|
|Whole Body||5 Rem/year||0.5 Rem||1.5 Rem|
|Extremity||50 Rem/year||5 Rem||15 Rem|
For a Level 1 investigation, individuals are notified of their exposure and asked to evaluate work practices with the purpose of reducing future exposure.
For a Level 2 investigation, a Radiation Safety staff physicist reviews the root causes for the exposure with the individual, and methods are implemented to control future exposures.
A summary of exposure for all individuals exceeding these levels is presented to the University Radiation Safety Committee at its quarterly meeting.