Patient Release After Radionuclide Therapy
Projected dose to others and release status under NRC 10 CFR 35.75 (Regulatory Guide 8.39)
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Under 10 CFR 35.75, a patient may be released if the total effective dose to any other individual is unlikely to exceed 5 mSv; written radiation-safety instructions are required whenever that dose is likely to exceed 1 mSv. This calculator uses the standard Regulatory Guide 8.39 approach — projecting the dose from the measured dose rate at 1 metre and the effective half-life, with a default occupancy factor of 0.25. Leave the physical half-life for a conservative upper bound, or enter a measured effective half-life for a patient-specific estimate.
Patient release — projected dose to others (10 CFR 35.75)
Projected total effective dose to the maximally-exposed individual = dose‑rate(1 m) × 1.44 × Teff × E (Reg. Guide 8.39). Release if ≤ 5 mSv; provide written instructions if > 1 mSv. The physical half-life (auto-filled) is a conservative upper bound because it ignores biological clearance — enter a measured effective half-life for a patient-specific estimate. Occupancy 0.25 is the RG 8.39 default. Breastfeeding is a separate determination (may require interruption/cessation). Educational estimate — the authorized user and RSO make the release decision per your institutional protocol.