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—
(2)
Calibrate two separated readings on each scale or decade that will be used to show compliance; and
(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.