333-116-0580 Periodic Spot-Checks for Teletherapy Units (1) A licensee authorized to use teletherapy units for medical use must perform output spot-checks on each teletherapy unit at intervals not to exceed one month that include the determination of: (a) Timer constancy, accuracy, and linearity over the range of use; (b) On-off error; (c) The coincidence of the radiation field and the field indicated by the light beam localizing device; (d) The accuracy of all distance measuring and localization devices used for medical use; (e) The output for one typical set of operating conditions measured with the dosimetry system described in OAR 333-116-0560; and (f) The difference between the measurement made in section (1) of this rule and the anticipated output, expressed as a percentage of the anticipated value obtained at last full calibration corrected mathematically for physical decay. (2) A licensee must use the dosimetry system described in OAR 333-116-0560 to make the measurement required in section (1) of this rule. (3) A licensee must perform measurements required by section (1) of this rule in accordance with procedures established by the teletherapy or medical physicist. That individual is not required to actually perform the output spot-check measurements. (4) A licensee must have the teletherapy or medical physicist review the results of each output spot-check within 15 days of each measurement. The teletherapy or medical physicist must promptly notify the licensee in writing of the results of each output spot-check. The licensee must keep a copy of each written notification in accordance with OAR 333-100-0057. (5) A licensee authorized to use a teletherapy unit for medical use must perform safety spot-checks of each teletherapy facility at intervals not to exceed one month and after each source installation to assure proper operation of: (a) Electrical interlocks at each teletherapy room entrance; (b) Electrical or mechanical stops installed for the purpose of limiting use of the primary beam of radiation restriction of source housing angulation or elevation, carriage or stand travel and operation of the beam on-off mechanism; (c) Beam condition indicator lights on the teletherapy unit, on the control console and in the facility; (d) Viewing systems; (e) Treatment room doors from inside and outside the treatment room; and (f) Electrically assisted treatment room doors with the teletherapy unit electrical power turned "off". (6) A licensee must lock the control console in the "off" position if any door interlock malfunctions. No licensee must use the unit until the interlock system is repaired unless specifically authorized by the Authority. (7) A licensee must promptly repair any system identified in section (5) of this rule that is not operating properly. (8) A licensee must retain a record of each spot-check required by sections (1) and (5) of this rule in accordance with OAR 333-100-0057. The record must include, the date of the spot-check, the manufacturer's name, model number and serial number for both the teletherapy unit and source, the manufacturer's name, model number and serial number of the instrument used to measure the output of the teletherapy unit, the measured timer accuracy, the calculated on-off error, a determination of the coincidence of the radiation field and the field indicated by the light beam localizing device, the measured timer accuracy for a typical treatment time, the calculated on-off error, the estimated accuracy of each distance measuring or localization device, the difference between the anticipated output and the measured output, notations indicating the operability of each entrance door electrical interlock, each electrical or mechanical stop, each beam condition indicator light, the viewing system and doors and the signature of the individual who performed the periodic spot-check. Statutory/Other Authority: ORS 453.635 Statutes/Other Implemented: ORS 453.605 - 453.807 History: PH 53-2018, minor correction filed 02/01/2018, effective 02/01/2018 PH 14-2008, f. & cert. ef. 9-15-08 PH 4-2007, f. & cert. ef. 3-1-07 PH 12-2006, f. & cert. ef. 6-16-06 PH 36-2004, f. & cert. ef. 12-1-04 PH 31-2004(Temp), f. & cert. ef. 10-8-04 thru 4-5-05 PH 3-2003, f. & cert. ef. 3-27-03 HD 1-1991, f. & cert. ef. 1-8-91