What is the key safety QA requirement across ALL modalities?

• A. Interlocks must be reconfigured weekly
• B. Interlocks are tested annually
• C. All safety systems must be functional and tested daily
• D. No safety QA is required

Answer: (C)

Daily verification of safety systems is the baseline requirement across all modalities. This means every safety-related component—interlocks, alarms, beam control, and related safety gates or door interlocks—must be functional and verified before each treatment session. Catching a fault the day it could affect a patient protects against accidental delivery of radiation or dose errors and keeps risk at a minimum.

Relying on weekly changes to interlocks or testing interlocks only once a year leaves dangerous gaps where a fault could go unnoticed for days or weeks, which is not acceptable for patient safety. Saying that no safety QA is required contradicts the fundamental duty to verify that the treatment device operates safely. Daily checks align with standard safety practice across modalities, ensuring the system is prepared for each patient and reducing the chance of unsafe treatment delivery.