CFR > Title 10 - Energy > CHAPTER I—NUCLEAR REGULATORY COMMISSION > PART 35—MEDICAL USE OF BYPRODUCT MATERIAL > SUBPART C—General Technical Requirements (§35.60 to §35.92) > 35.61—Calibration of survey instruments.

35.61—Calibration of survey instruments.

(a) A licensee shall calibrate the survey instruments used to show compliance with this part and 10 CFR Part 20 before first use, annually, and following a repair that affects the calibration. A licensee shall—
(1) Calibrate all scales with readings up to 10 mSv (1000 mrem) per hour with a radiation source;
(2) Calibrate two separated readings on each scale or decade that will be used to show compliance; and
(3) Conspicuously note on the instrument the date of calibration.
(b) A licensee may not use survey instruments if the difference between the indicated exposure rate and the calculated exposure rate is more than 20 percent.
(c) A licensee shall retain a record of each survey instrument calibration in accordance with § 35.2061.