Minnesota Administrative Rules

4731.4468 DOSIMETRY EQUIPMENT.

Subpart 1.

Required equipment.

Except for low dose-rate remote afterloader sources where the source output or activity is determined by the manufacturer, a licensee must have a calibrated dosimetry system available for use. To satisfy this requirement:

A.

the system must have been calibrated by a calibration laboratory accredited by the American Association of Physicists in Medicine (AAPM) or by using a source or system traceable to the National Institute of Standards and Technology (NIST) and published protocols accepted by nationally recognized bodies:

(1)

within the previous two years; and

(2)

after any servicing that may have affected system calibration; or

B.

the system must have been calibrated within the previous four years. Eighteen to 30 months after that calibration:

(1)

the system must have been intercompared with another dosimetry system that was calibrated within the past 24 months by NIST or by a calibration laboratory accredited by the AAPM; and

(2)

the results of the intercomparison must have indicated that the calibration factor of the licensee's system had not changed by more than two percent. The licensee may not use the intercomparison result to change the calibration factor. When intercomparing dosimetry systems to be used for calibrating sealed sources for therapeutic units, the licensee must use a comparable unit with a beam attenuator or collimators, as applicable, and sources of the same radionuclide as the source used at the licensee's facility.

Subp. 2.

Spot check measurements.

A licensee must have a dosimetry system available for spot check output measurements, if applicable. To satisfy this requirement, the system may be compared with a system that has been calibrated according to subpart 1. The comparison must have been performed within the previous year and after each servicing that may have affected system calibration. The spot check system may be the same system used to meet the requirement under subpart 1.

Subp. 3.

Record retention.

A licensee must retain a record of each calibration, intercomparison, and comparison according to part 4731.4517.

Statutory Authority:

MS s 144.1202; 144.1203

History:

29 SR 755

Published Electronically:

March 12, 2009