On Monday, March 13, 2023, ASTRO submitted a petition for rulemaking in Massachusetts to include accreditation requirements for radiation oncology facilities and to differentiate between CT used for diagnosis and CT used for radiation oncology simulation. Current regulations require all CT scanners be accredited by ACR, even those used for simulation. The requested changes distinguish between diagnostic CT and CT simulation and include a requirement for each registrant providing radiation therapy with therapeutic radiation equipment, including CT simulators, to either maintain accreditation or conduct an external audit. ASTRO believes that facilities that obtain practice accreditation have the appropriate systems, personnel and policies and procedures that are needed for high-quality patient care.