Section 180-20-004 - GENERAL TECHNICAL REQUIREMENTS FOR REGISTRANTS OF THERAPEUTIC RADIATION MACHINES The general technical requirements for registrants using therapeutic radiation machines are as follows.
004.01PROTECTION SURVEYS. Radiation protection surveys must be conducted as follows. 004.01(A)RADIATION SURVEY INSTRUMENT. The registrant must ensure that radiation protection surveys of all new facilities, and existing facilities not previously surveyed, are performed with an operable radiation measurement survey instrument calibrated according to 180 NAC 20-008. The radiation protection survey must be performed by, or under the direction of, a radiological medical physicist. The radiological medical physicist must verify, with the therapeutic radiation machine in a "BEAM-ON" condition, with the largest clinically available treatment field and with and without a scattering phantom in the useful beam of radiation: (i) Radiation levels in restricted areas are not likely to cause personnel exposures in excess of the limits specified in 180 NAC 4-005.01; and(ii) Radiation levels in unrestricted areas do not exceed the limits specified in 180 NAC 4-013.01 and 180 NAC 4-013.02. 004.01(B)ADDITIONAL REQUIREMENTS. In addition to the requirements of 180 NAC 20-004.01(A), a radiation protection survey must also be performed prior to any subsequent medical use and: (i) After making any change in the treatment room shielding;(ii) After making any change in the location of the therapeutic radiation machine within the treatment room;(iii) After relocating the therapeutic radiation machine; or(iv) Before using the therapeutic radiation machine in a manner that could result in increased radiation levels in areas outside the external beam radiation therapy treatment room.004.01(C)VIOLATIONS. The survey record must indicate all instances where the registrant, in the opinion of the radiological medical physicist, is in violation of applicable regulations. The survey record must also include: (i) The date of the measurements;(ii) The reason the survey is required;(iii) The manufacturer's name;(iv) The model number and serial number of the therapeutic radiation machine;(v) The instrument or instruments used to measure radiation levels;(vi) A plan of the areas surrounding the treatment room that were surveyed;(vii) The measured dose rate at several points in each area expressed in microsieverts or millirems per hour;(viii) The calculated maximum level of radiation over a period of one week for each restricted and unrestricted area; and(ix) The signature of the individual responsible for conducting the survey.004.01(D)PROHIBITION OF USE. If the results of the surveys required by 180 NAC 20-004.01(A) or (B) indicate any radiation levels in excess of the respective limit specified in 180 NAC 20-004.01(A), the registrant must lock the control in the "OFF" position and not use the unit: (i) Except as may be necessary to repair, replace, or test the therapeutic radiation machine, the therapeutic radiation machine shielding, or the treatment room shielding; or(ii) Until the registrant has received a specific exemption from the Department.004.02MODIFICATION OF RADIATION THERAPY UNIT OR ROOM BEFORE BEGINNING A TREATMENT PROGRAM. If the survey required by 180 NAC 20-004.01 indicates that an individual in an unrestricted area may be exposed to levels of radiation greater than those permitted by 180 NAC 4-013.01 and 4-013.02, before beginning the treatment program the registrant must: (A) Either equip the unit with beam direction interlocks or add additional radiation shielding to ensure compliance with 180 NAC 4-013.01 and 4-013.02;(B) Perform the survey required by 180 NAC 20-004.01 again; and(C) Include in the report required by 180 NAC 20-004.04 the results of the initial survey, a description of the modification made to comply with 180 NAC 20-004.01(A), and the results of the second survey; or(D) Request and receive a registration amendment under 180 NAC 4-013.04 that authorizes radiation levels in unrestricted areas greater than those permitted by 180 NAC 4-013.01 and 4-013.02.004.03DOSIMETRY EQUIPMENT. The requirements for use of dosimetry equipment are as follows.004.03(A)CALIBRATED DOSIMETRY SYSTEM. The registrant must have a calibrated dosimetry system available for use. The system must have been calibrated by the National Institute for Standards and Technology (NIST) or by an American Association of Physicists in Medicine (AAPM) Accredited Dosimetry Calibration Laboratory (ADCL). The calibration must have been performed within the previous 24 months and after any servicing that may have affected system calibration. The dosimetry system must have been calibrated at an energy or energy range appropriate for the radiation being measured.004.03(B)QUALITY ASSURANCE CHECK MEASUREMENTS. The registrant must have available for use a dosimetry system for quality assurance check measurements. To meet this requirement, the system may be compared with a system that has been calibrated according to 180 NAC 20-004.03(A). This comparison must have been performed within the previous 12 months and after any servicing that may have affected the system calibration. The quality assurance check system may be the same system used to meet the requirement in 180 NAC 20-004.03(A).004.03(C)RECORDS. The registrant must maintain a record of each dosimetry system calibration, intercomparison, and comparison for the duration of the registration. For each calibration, intercomparison, or comparison, the record must include: (ii) The model numbers and serial numbers of the instruments that were calibrated, inter-compared, or compared as required by 180 NAC 20-004.03(A) and (B); the correction factors that were determined; (iii) The names of the individuals who performed the calibration, intercomparison, or comparison; and(iv) Evidence that the intercomparison was performed by, or under the direct supervision and in the physical presence of, a radiological medical physicist.180 Neb. Admin. Code, ch. 20, § 004
Amended effective 11/21/2020