Facilities and equipment

Shielding calculations for RLT treatment rooms

When designing a facility for ¹⁷⁷Lu-based RLTs, it is essential to perform shielding calculations that comply with regulatory standards for radiation protection.¹ These standards include dose rate limits and restrictions:

Controlled Areas: These are areas occupied by employees or staff whose occupational radiation dose is regularly monitored. For workers who are exposed to radiation, the dose equivalent must be below 50 mSv/year²

Uncontrolled Areas: These areas are occupied by visitors or employees who do not routinely work with radiation sources. Examples include offices, public hallways, or adjacent rooms. The radiation dose rate in these areas must not exceed 1 mSv/year^3,4

Factors affecting shielding requirements:

1. Radionuclide: physical half-life, emission types, and energies of the gamma photons⁵
2. Treatment procedure protocol: administered dosage and the length of the procedure⁵
3. Dose rate: dose rate constants, patient self-attenuation, decay, number of patients per week (work factor)^3,5,6
4. Facility layout: controlled vs uncontrolled areas, occupancy factor^5,7
5. Regulatory limits in each area⁵