Patient Release Criteria Help

NPC Patient Release Calculation

This program is intended as a mathematical aid only. The criteria outlined in USNRC Regulatory Guide 8.39 must be met prior to the release of any patient.

Initial Activity: Total activity implanted in the patient (in millicuries). For informational purposes only.

Initial Exposure Rate: Measured exposure rate at 1 meter from the patient (in mR/h). The calculated dose is based on this value.

Occupancy Factor: Regulatory Guide 8.39 recommends an occupancy factor of 0.25 when the half-life is greater than 1 day and appropriate radiation safety instruction is provided to the patient. An occupancy factor of 0.125 may be used under certain circumstances and given appropriate instruction. See Regulaltory Guide 8.39 for details and documentation requirements.

Distance to patient: The distance at which the dose to other individuals is calculated. The occupancy factors are defined at this distance. Regulatory Guide 8.39 specifies a distance of 1 meter. (Distance must be entered in cm.)

Last modified: October 23, 2009