Section 221.74. Calibration

(a) The calibration of an X-ray system shall be performed at intervals not to exceed 1 year and after a change of replacement of components which could cause a change in the radiation output.

(b) The calibration of the radiation output of the X-ray system shall be performed by or under the direction of a qualified expert for radiation therapy calibration who is physically present at the facility during the calibration.

(c) The calibration of the radiation output of an X-ray system shall be performed with a calibrated instrument. The calibration of the instrument shall be traceable to a National standard. The instrument shall have been calibrated within the preceding 2 years.

(d) Calibrations made under this section shall be made so that the dose at a reference point in soft tissue may be calculated as accurately as possible but with an uncertainty of no greater than 5%.

(e) The calibration of the X-ray system shall include, but is not limited to, the following determinations:

(1) The exposure rates for each combination of field size, technique factors, filter and treatment distance used.

(2) The degree of congruence between the radiation field and the field indicated by the localizing device if a device is present.

(3) An evaluation of the uniformity of the largest radiation field used.

(f) Records of calibration performed under this section shall be maintained by the registrant for at least 5 years after completion of the calibration.

(g) A copy of the most recent X-ray system calibration shall be available at the control panel.

The provisions of this § 221.74 adopted December 18, 1987, effective December 19, 1987, 17 Pa.B. 5235; amended July 16, 2004, effective July 17, 2004, 34 Pa.B. 3823. Immediately preceeding text appears at serial pages (249309) to (249310).

Notation

Authority

The provisions of this § 221.74 issued under section 302 of the Radiation Protection Act (35 P. S. § 7110.302); and section 1920-A of The Administrative Code of 1929 (71 P. S. § 510-20); amended under sections 301 and 302 of the Radiation Protection Act (35 P. S. § § 7110.301 and 7110.302); and section 1920-A of The Administrative Code of 1929 (71 P. S. § 510-20).

Cross References

This section cited in 25 Pa. Code § 221.75 (relating to spot checks).