Minnesota: radiation safety rules for fluoroscopy teams

Yes. Minnesota is an NRC Agreement State.

Minnesota Rules chapter 4732, "Ionizing Radiation," covers radiation-producing equipment; radioactive materials are excluded and covered by chapter 4731. X-ray dose standards are in parts 4732.0400-4732.0440, safety parts in 4732.0500-4732.0590, and fluoroscopy rules in 4732.0825 and 4732.0830. Statutory authority is Minn. Stat. § 144.121. Most parts date from 2007 (32 SR 777); 4732.0110 shows October 13, 2021.

Yes. Registrants must use procedures and engineering controls to keep occupational and public doses ALARA. ALARA is defined in 4732.0110, subp. 11, and 4732.0550, subp. 1(C) applies ALARA to patient exposure.

Where ALARA lives in Minnesota: In X-ray-specific rules. The X-ray ALARA duty is in chapter 4732 (part 4732.0530), which excludes radioactive materials. Licensees have a separate radiation protection program requirement in 4731.2010. No shared part applies to both, so an NRC-driven change to chapter 4731 would not automatically change 4732.0530. The 4731 ALARA definition refers to "licensed or registered" activity, but chapter 4731 is limited to radioactive materials. (Minn. R. 4732.0530 (X-ray); Minn. R. 4731.2010 (radioactive materials))

5 rem (50 mSv) total effective dose equivalent per year.

15 rem (150 mSv) lens dose equivalent per year; no lower International Commission on Radiological Protection (ICRP) 20 mSv limit has been adopted.

50 rem (500 mSv) shallow dose equivalent to the skin or any extremity per year.

0.5 rem (5 mSv) to the embryo/fetus of a declared pregnant woman over the whole pregnancy, with a reasonable effort to stay at or below 0.05 rem (0.5 mSv) per month.

Dosimeters must be supplied and worn by: adults likely to exceed 10% of the 4732.0410 limits in a year; declared pregnant women likely to exceed 0.1 rem (1.0 mSv) over the pregnancy; anyone entering a high or very high radiation area; and minors likely to exceed 0.1 rem (1.0 mSv) in a year. Badges may not be shared, and workers get an annual written dose report.

With an apron, the badge is worn at the collar outside the apron. If more than one badge is worn, records must show each badge's location and whether it was over or under the apron. A declared pregnant worker wears an abdomen badge under the lead. Whole-body dose methods are: (1) single collar badge deep dose taken as whole-body dose; (2) single collar badge deep dose × 0.3; (3) two badges: 1.5 × waist badge under the apron + 0.04 × collar badge outside the apron. Other methods need commissioner approval. Items (1) and (2) conflict, which appears to be a drafting error. The rule does not name National Council on Radiation Protection and Measurements (NCRP) Report 122 or Webster.

Required. Anyone in the room during fluoroscopy must wear a garment of at least 0.5 mm lead equivalence; this is repeated for over-table units and portable C-arms (4732.0825, subp. 8(C)-(D)). No body part may be in the useful beam unless covered by 0.5 mm lead equivalent. Thyroid and eye protection is required only if the worker's potential exposure would exceed the 4732.0410 limits. Personal protective garments include aprons, gloves and thyroid collars.

Yes. Protective garments must be checked for integrity when first put into use and at least every 24 months, with records kept. The rule sets no method or pass/fail standard. MDH guidance says checks may be done with fluoroscopy and that MDH has no rule defining failure.

Not addressed. Chapter 4732 does not mention engineered shielding systems as replacements for garments, and the garment rule has no exception. Fixed shielding (bucky-slot cover, lead drapes or self-supporting shields) is required in addition to garments, not instead of them. A 2014 MDH notice on protective barriers and the variance part 4732.0308 were not read.

These may operate: licensed practitioners of the healing arts, physician assistants, registered radiologist assistants or radiology practitioner assistants, and people who passed an exam under § 144.121, subd. 5 (e.g., American Registry of Radiologic Technologists (ARRT) radiography). Limited-scope operators may not use fluoroscopy. Cardiovascular technologists may assist under personal supervision but may not activate the beam. No general physician-supervision rule for technologists was found, and nurse practitioner status is unresolved.

Non-practitioners must pass a national or state exam (effectively ARRT radiography for fluoroscopy). Anyone who activates a fluoroscope, except licensed practitioners, must be trained and documented in ten topics (items A-J). All operators get facility- and system-specific instruction at the start and when the quality assurance (QA) program or radiation output changes. No state fluoroscopy permit, minimum hours, continuing education, or physician fluoroscopy training was found.