Class II Nuclear Facilities and Prescribed Equipment Regulations

15 (1) This section applies to licensees who operate Class II nuclear facilities other than facilities that include brachytherapy remote afterloaders that incorporate pure beta emitters as their only nuclear substances or facilities that include particle accelerators used for geophysical logging.

(2) Each entrance door to a room in which Class II prescribed equipment is located shall be

• (a) equipped with a device that stops the equipment when the door is opened and prevents the equipment from being used when the door is open;

• (b) equipped with a device that prevents the equipment from being used until a person activates the device from inside the room, leaves the room and closes the door within a preset time; and

• (c) designed to prevent any person from being locked inside the room.

(3) Each entrance, other than a door, to a room in which Class II prescribed equipment is located shall be equipped with

• (a) a device that stops the equipment when a person passes through the entrance; and

• (b) a device that prevents the equipment from being used until a person activates the device from inside the room and leaves the room within a preset time.

(4) Every room in which Class II prescribed equipment that is used on persons is located shall be equipped with a viewing system that allows the operator to view the interior of the treatment room during operation of the equipment.

(5) Each entrance to a room in which Class II prescribed equipment is located shall be equipped with a readily visible display that indicates the irradiation state of the equipment.

(6) Every room in which Class II prescribed equipment — other than a particle accelerator — is located shall be equipped with an area radiation monitoring system that

• (a) is independent of the Class II prescribed equipment;

• (b) produces an audible alarm when a person enters the room while the equipment is delivering a dose of radiation; and

• (c) has an independent back-up power supply.

(7) Every room in which Class II prescribed equipment that is not used on persons is located shall be equipped with a device that, before the irradiation begins, provides a continuous audible alarm of sufficient duration to enable a person inside the room to operate one of the emergency stop buttons or other emergency stop devices referred to in subsection (8).

(8) Every room in which Class II prescribed equipment is located shall be equipped with emergency stop buttons or other emergency stop devices located as specified in subsections (9) and (10) that, when any one of them is operated, cause all Class II prescribed equipment in the room to automatically revert to a safe state until the safety circuit is reset from inside that room and a switch on the control console of the equipment is operated.

(9) The emergency stop buttons or other emergency stop devices shall be unobstructed, accessible and located at a minimum in each of the following places:

• (a) on the control console of all Class II prescribed equipment;

• (b) near each entrance to the room in which Class II prescribed equipment is located; and

• (c) on both sides of all Class II prescribed equipment — other than a brachytherapy remote afterloader — or on the wall on both sides of the equipment.

(10) In the case of a teletherapy machine, the emergency stop buttons or other emergency stop devices shall be unobstructed, accessible and located in accordance with paragraphs (9)(b) and (c) in places that are not in the machine’s direct beam.

(11) Every licensee shall post and keep posted at every entrance to a Class II nuclear facility a visible, durable and legible sign that indicates the name or job title and the telephone number of a person who can initiate any required emergency procedure and who can be contacted 24 hours a day.

(12) Class II prescribed equipment shall be equipped with a key switch or code-operated device that prevents persons who are not authorized by the licensee from operating the equipment.

(13) After a device or system referred to in subsection (2), (3), (5), (6), (7) or (8) is serviced, the licensee shall not use the Class II prescribed equipment until the licensee performs a test or an inspection that establishes that the device is functioning as prescribed by those subsections.

(14) Subsections (2), (3) and (7) and paragraphs (9)(b) and (c) do not apply in respect of a particle accelerator that meets at least one of the following criteria:

• (a) its radiation dose rate at 30 cm is not greater than 200 µSv per hour when it is being operated in the manner that produces the maximum dose rate as limited either by its characteristics or by its interlocks, and it is located in a room that is equipped with a lock and that can be unlocked and entered only by persons who have been authorized by the licensee; or

• (b) its radiation dose rate at 30 cm is not greater than 25 µSv per hour when it is being operated in the manner that produces the maximum dose rate as limited either by its characteristics or by its interlocks.

(15) Paragraphs (2)(b), (3)(b) and (9)(b) do not apply in respect of a brachytherapy remote afterloader that contains a total quantity of nuclear substance that, if exposed, would produce a radiation dose rate in air of less than 10 mGy per hour at a distance of 1 m.