NAC459.602. X-ray and electron therapy installations: Switches; timers.

     1. It must be possible to terminate irradiation and equipment movements or to go from an interruption condition to termination conditions at any time from the treatment control panel.

     2. It must be possible to interrupt irradiation and equipment movements at any time from the treatment control panel. Following an interruption it must be possible to restart irradiation by operator action without any reselection of operating conditions.

     3. A timer must be provided which has a display at the treatment control panel. The timer must have a preset time selector and an elapsed time indicator.

     4. The timer must be a cumulative timer which switches on and off with the radiation and retains its reading after irradiation is interrupted or terminated. It must be necessary to zero and reset the elapsed time indicator and the preset time selector after irradiation is terminated before irradiation will again be possible.

     5. To guard against failure of the dose monitoring systems, the timer must terminate irradiation when a preselected time has elapsed.

     [Bd. of Health, Radiation Control Reg. §§ 6.9.1.7-6.9.1.9.3, eff. 2-28-80]