(1) The licensee or registrant shall maintain sufficient calibrated and operable radiation survey instruments to make physical radiation surveys as required by this subchapter and ARM 37.14.720. Instrumentation required by this rule shall have a range such that 2 milliroentgens per hour through 1 roentgen per hour can be measured.

(2) Each radiation survey instrument shall be calibrated:

(a) at energies appropriate for use and at intervals not to exceed 3 months and after each instrument servicing;

(b) such that accuracy within ± 20% can be demonstrated; and

(c) at 2 or more widely separated points, other than zero, on each scale.

(3) Records shall be kept of these calibrations for 2 years after the calibration date and maintained for inspection by the department.