Tenn. Comp. R. & Regs. 0400-20-07-.74 - PERIODIC SPOT-CHECKS FOR GAMMA STERIOTACTIC RADIOSURGERY UNITS

(1) A licensee authorized to use a gamma stereotactic radiosurgery unit for medical use shall perform spot-checks of each gamma stereotactic radiosurgery facility and on each unit:

(a) Monthly;

(b) At the beginning of each day of use; and

(c) After each source installation.

(2) A licensee shall have the authorized medical physicist:

(a) Establish written procedures for performing the spot-checks required in paragraph (1) of this rule; and

(b) Review the results of each spot-check required by paragraph (1) of this rule within 15 days of the check. The authorized medical physicist need not actually perform the spot-check measurements. The authorized medical physicist shall notify the licensee as soon as possible, in writing, of the results of the spot check.

(3) To satisfy the requirements of subparagraph (1)(a) of this rule, spot-checks must, at a minimum:

(a) Assure proper operation of:

1. Treatment table retraction mechanism, using backup battery power or hydraulic backups with the unit off;

2. Helmet microswitches;

3. Emergency timing circuits; and

4. Stereotactic frames and localizing devices (trunnions).

(b) Determine:

1. The output for one typical set of operating conditions measured with the dosimetry system described in paragraph (2) of Rule 0400-20-07-.68;

2. The difference between the measurement made in part 1 of this subparagraph and the anticipated output, expressed as a percentage of the anticipated output (i.e., the value obtained at last full calibration corrected mathematically for physical decay);

3. Source output against computer calculation;

4. Timer accuracy and linearity over the range of use;

5. On-off error; and

6. Trunnion centricity.

(4) To satisfy the requirements of subparagraphs (1)(b) and (c) of this rule, spot-checks must assure proper operation of:

(a) Electrical interlocks at each gamma stereotactic radiosurgery room entrance;

(b) Source exposure indicator lights on the gamma stereotactic radiosurgery unit, on the control console, and in the facility;

(c) Viewing and intercom systems;

(d) Timer termination;

(e) Radiation monitors used to indicate room exposures; and

(f) Emergency off buttons.

(5) A licensee shall arrange for the repair of any system identified in paragraph (3) of this rule that is not operating properly as soon as possible. .

(6) If the results of the checks required in paragraph (4) of this rule indicate the malfunction of any system, a licensee shall lock the control console in the off position and not use the unit except as may be necessary to repair, replace, or check the malfunctioning system.

(7) A licensee shall retain a record of each check required by paragraphs (3) and (4) of this rule in accordance with 0400-20-07-.107.

Notes

Tenn. Comp. R. & Regs. 0400-20-07-.74

Original rule filed February 22, 2012; effective May 22, 2012.

Authority: T.C.A. §§ 68-202-101 et seq., 68-202-201 et seq. and 4-5-201 et seq.