How often must the QA tests on external beam therapy equipment be performed?

The requirement for conducting quality assurance (QA) tests on external beam therapy equipment is vital to ensure that the equipment operates correctly and safely throughout its use. Performing these tests periodically—as well as after major repairs—ensures the equipment maintains its performance standards and operational safety.

Regular QA testing helps identify potential issues before they affect patient treatment, and following any significant repair is critical because repairs can introduce variability in equipment performance. Such measures are in line with guidelines from organizations like the American Association of Physicists in Medicine (AAPM), which advocate for routine testing to monitor and maintain accuracy, precision, and reliability in radiation therapy delivery.

This approach contrasts with only conducting tests prior to treatment (which would not account for ongoing operational wear), annual testing (which may not catch issues that arise in between), or weekly testing (which may be excessively frequentity for certain equipment based on established protocols). By emphasizing both periodic testing and post-repair assessments, the answer supports a proactive approach to patient safety and treatment effectiveness.