Wisconsin Legislature: DHS 157.67(4)(b)

History: CR 01-108: cr. Register July 2002 No. 559, eff. — see Note at the start of the chapter; CR 06-021: r. and recr. (2) Register October 2006 No. 610, eff. 11-1-06; CR 22-015: r. and recr. (1), am. (2) (intro.) cr. (2) (c) Register June 2023 No. 810, eff. 7-1-23.

DHS 157.67 Photon emitting remote afterloader, teletherapy and gamma stereotactic radiosurgery units.

(1) Use of a sealed source in a remote afterloader, teletherapy or gamma stereotactic radiosurgery unit.

(a) A licensee shall use sealed sources in photon emitting remote afterloader units, teletherapy units or gamma stereotactic units for therapeutic medical uses that meet any of the following criteria:

1. Is approved in the sealed source and device registry.

Note: The sealed source and device registrations may be obtained from the manufacturer or by writing the department at: Department of Health Services, Radiation Protection Section, P.O. Box 2659, Madison WI 53701-2659.

2. In research involving photon-emitting remote afterloader units, teletherapy units, or gamma stereotactic radiosurgery units in accordance with an active effective investigational device exemption application accepted by the FDA provided the requirements of s. DHS 157.61 (6) (a) are met.

Note: The FDA requirements for investigational devices may be found at: http://www.fda.gov/radiation-emittingproducts/default.htm.

(b) A licensee shall use photon-emitting remote afterloader units, teletherapy units, or gammastereotactic radiosurgery units that meet any of the following criteria:

1. Is approved in the sealed source and device registry to deliver a therapeutic dose for medical use. These devices may be used for therapeutic medical treatments that are not explicitly provided for in the sealed source and device registry, but must be used in accordance with radiation safety conditions and limitations described in the sealed source and device registry.

2. In research in accordance with an active investigational device exemption application accepted by the FDA and provided the requirements of s. DHS 157.61 (6) are met.

(2) Surveys of patients and human research subjects treated with a remote afterloader unit.

(a) Before releasing a patient or a human research subject from licensee control, a licensee shall make a survey of the patient or the human research subject and the remote afterloader unit with a portable radiation detection survey instrument to confirm that the source has been removed from the patient or human research subject and returned to the safe shielded position.

(b) A licensee shall retain a record of the surveys under s. DHS 157.71 (16).

(3) Installation, maintenance, adjustment and repair.

(a) A person shall be specifically licensed by the department, NRC or another agreement state to install, maintain, adjust or repair a remote afterloader unit, teletherapy unit or gamma stereotactic radiosurgery unit that involves work on the source shielding, the source driving unit used to move the source or other electronic or mechanical component that could expose the source, reduce the shielding around the source or compromise the radiation safety of the unit or the source.

(b) Except for low dose-rate remote afterloader units, only a person specifically licensed by the department, NRC or another agreement state may install, replace, relocate or remove a sealed source or source contained in other remote afterloader units, teletherapy units or gamma stereotactic units.

(c) For a low dose-rate remote afterloader unit, only a person specifically licensed by the department, NRC or another agreement state, or an authorized medical physicist, shall install, replace, relocate or remove a sealed source contained in the unit.

(d) A licensee shall retain a record of the installation, maintenance, adjustment and repair done on remote afterloader units, teletherapy units and gamma stereotactic radiosurgery units under s. DHS 157.71 (19).

(4) Safety procedures and instructions for remote afterloader, teletherapy and gamma stereotactic radiosurgery units.

(a) A licensee shall do all of the following:

1. Secure the unit, console, console keys and the treatment room when unattended or not in use.

2. Permit only individuals approved by the authorized user, radiation safety officer or authorized medical physicist to be present in the treatment room during treatment with the source.

3. Prevent dual operation of more than one radiation producing device in a treatment room, if applicable.

4. Develop, implement and maintain written procedures for responding to an abnormal situation when the operator is unable to place the source in the shielded position or remove the patient or human research subject from the radiation field with controls from outside the treatment room. The procedure shall include all the following:

a. Instructions for responding to equipment failures and the names of the persons responsible for implementing corrective actions.

b. The process for restricting access to and posting signs in the proximity of the treatment area to minimize the risk of inadvertent exposure.

c. The names and telephone numbers of the authorized users, the authorized medical physicist and the radiation safety officer to be contacted if the unit or console operates abnormally.

(b) A copy of the procedures required by par. (a) 4. shall be physically located at the unit console.

1. The location of the procedures required by par. (a) 4.

2. The names and telephone numbers of the authorized users, the authorized medical physicist and the radiation safety officer to be contacted if the unit or console operates abnormally.

(d) A licensee shall provide operational and safety instruction, initially and at least annually, at intervals not to exceed 13 months, to all persons who operate the unit, as appropriate to the person’s assigned duties, in all of the following:

1. The procedures identified in par. (a) 4.

2. The operating procedures for the unit.

(e) A licensee shall ensure that operators, authorized medical physicists and authorized users participate in drills of the emergency procedures, initially and at least annually, at intervals not to exceed 13 months, thereafter.

(f) A licensee shall retain a record of individuals receiving instruction required under s. DHS 157.71 (15).

(g) Prior to the first use for patient treatment of a new unit or an existing unit with a manufacturer upgrade that affects the operation and safety of the unit, a licensee shall ensure that vendor operational and safety training is provided to all individuals who will operate the unit. The vendor operational and safety training must be provided by the device manufacturer or by an individual certified by the device manufacturer to provide the operational and safety training.

(h) A licensee shall retain a copy of the procedures required by pars. (a) 4. and (d) 2. until the licensee no longer possesses the remote afterloader, teletherapy unit, or gamma stereotactic radiosurgery unit.

(5) Safety precautions for remote afterloader, teletherapy and gamma stereotactic radiosurgery units.

(a) A licensee shall control access to the treatment room by a door at each entrance.

(b) A licensee shall equip each entrance to the treatment room with an electrical interlock system that accomplishes all the following:

1. Prevents the operator from initiating the treatment cycle unless each treatment room entrance door is closed.

2. Causes the source to be shielded promptly when an entrance door is opened.

3. Prevents the source from being exposed following an interlock interruption until all treatment room entrance doors are closed and the source on-off control is reset at the console.

(c) A licensee shall require any person entering the treatment room to assure, via appropriate radiation monitors, that radiation levels have returned to ambient levels.

(d) Except for low-dose remote afterloader units, a licensee shall construct or equip each treatment room with viewing and intercom systems to permit continuous observation of the patient or the human research subject from the treatment console during irradiation.

(e) For licensed activities where sources are placed within the patient’s or human research subject’s body, a licensee shall only conduct treatments that allow for expeditious removal of a decoupled or jammed source.

(f) A licensee shall do all the following:

1. For medium dose-rate and pulsed dose-rate remote afterloader units, require all the following:

a. An authorized medical physicist and either an authorized user or a physician, under the supervision of an authorized user, who has been trained in the operation and emergency response for the unit to be physically present during the initiation of all patient treatments involving the unit.

b. An authorized medical physicist and either an authorized user or a person under the supervision of an authorized user who has been trained to remove the source applicator in the event of an emergency involving the unit to be immediately available during continuation of all patient treatments involving the unit.

2. For high dose-rate remote afterloader units, require all the following:

a. An authorized user and an authorized medical physicist to be physically present during the initiation of all patient treatments involving the unit.

b. An authorized medical physicist and either an authorized user or a physician, under the supervision of an authorized user, who has been trained in the operation and emergency response for the unit to be physically present during continuation of all patient treatments involving the unit.

3. For gamma stereotactic radiosurgery units, require an authorized user and an authorized medical physicist to be physically present throughout all patient treatments involving the unit.

4. Notify the radiation safety officer or his or her designee and an authorized user immediately if the patient or human research subject has a medical emergency or if the patient dies.

(g) A licensee shall have available near each treatment room, emergency response equipment, as applicable, to respond to all of the following:

1. A source inadvertently remaining in the unshielded position.

2. A source inadvertently lodged within the patient following completion of the treatment.

(6) Dosimetry equipment.

(a) Except for low dose-rate remote afterloader sources where the source output or activity is determined by the manufacturer, a licensee shall have a calibrated dosimetry system available for use. To satisfy this requirement, one of the following conditions shall be met:

1. The system shall have been calibrated using a system or source traceable to the national institute of standards and technology and published protocols accepted by nationally recognized bodies, or by a calibration laboratory accredited by the American association of physicists in medicine. The calibration shall have been performed within the previous 2 years and after any servicing that may have affected system calibration.

Note: An example of a nationally recognized body is the American Association of Physicists in Medicine.

2. The system shall have been calibrated within the previous 4 years. Eighteen to 30 months after that calibration, the system shall have been compared to another dosimetry system that was calibrated within the past 24 months by the national institute of standards and technology or by a calibration laboratory accredited by the American association of physicists in medicine. The results of the comparison shall have indicated that the calibration factor of the licensee’s system had not changed by more than 2%. A licensee may not use the intercomparison result to change the calibration factor. When comparing dosimetry systems to be used for calibrating sealed sources for therapeutic units, a licensee shall use a comparable unit with beam attenuators or collimators, as applicable, and sources of the same radionuclide as the source used at the licensee’s facility.

(b) A licensee shall have available for use a dosimetry system for spot-check output measurements to periodically measure the radiation output of the device for consistency, if applicable. To satisfy this requirement, the system may be compared with a system that has been calibrated under par. (a). The comparison shall have been performed within the previous 12 months and after each servicing that may have affected system calibration. The spot-check system may be the same system used to meet the requirement in par. (a).

(7) Full calibration measurements on teletherapy units.

(a) A licensee authorized to use a teletherapy unit for medical use shall perform full calibration measurements on each teletherapy unit under any of the following circumstances:

1. Before the first medical use of the unit.

2. Before medical use under all of the following conditions:

a. Whenever spot-check measurements indicate that the output differs by more than 5% from the output obtained at the last full calibration corrected mathematically for radioactive decay.

b. Following replacement of the source or following reinstallation of the teletherapy unit in a new location.

c. Following any repair of the teletherapy unit that includes removal of the source or major repair of the components associated with the source exposure assembly.

3. At intervals not exceeding one year.

(b) To satisfy the requirements of par. (a), full calibration measurements shall include determination of all of the following:

1. The output within plus or minus 3% for the range of field sizes and for the distance or range of distances used for medical use.

2. The coincidence of the radiation field and the field indicated by the light beam localizing device.

3. The uniformity of the radiation field and its dependence on the orientation of the useful beam.

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

5. On-off error.

6. The accuracy of all distance measuring and localization devices in medical use.

(c) A licensee shall use the dosimetry system described in sub. (6) (a) to measure the output for one set of exposure conditions. The remaining radiation measurements required in par. (b) may be made using a dosimetry system that indicates relative dose rates.

(d) A licensee shall perform a full calibration required by par. (a) under published protocols accepted by nationally recognized bodies.

Note: An example of such a nationally recognized body is the American Association of Physicists in Medicine.

(e) A licensee shall mathematically correct the outputs determined in par. (b) 1. for physical decay for intervals not exceeding one month for cobalt-60, 6 months for cesium-137 or at intervals consistent with one percent decay for all other nuclides.

(f) Full calibration measurements required by par. (a) and physical decay corrections required by par. (e) shall be performed by an authorized medical physicist.

(g) A licensee shall retain a record of each calibration under s. DHS 157.71 (21).