What must be checked each time a source is returned to the shielded position?

When a source is returned to the shielded position, the use of a survey meter is essential to ensure safety and compliance with radiation protection standards. A survey meter measures radiation levels and helps confirm that no residual radiation is present in the area where the source was handled. This step is crucial for verifying that the source is properly shielded and that the surrounding area is safe for personnel and the public.

Using a survey meter not only provides immediate feedback about the radiation environment but also serves as a vital part of safety protocols that minimize exposure risks. Regularly checking radiation levels reinforces the importance of monitoring radioactive materials and ensuring that the appropriate shielding is effective. This practice is consistent with safety regulations and best practices in radiation safety management.