17. (1) Every fluoroscopic x-ray machine shall be equipped with, (a) an image intensification system that, (i) includes a shielded protective barrier and shielding such that, (A) the entire cross-section of the useful beam is intercepted within the protective barrier for any target-to-image distance, and (B) the fluoroscopic x-ray tube is not capable of producing x-rays unless the shielding is in place to intercept the useful beam, (ii) in the case of a mobile fluoroscopic x-ray machine, is an integral part of the machine or is interlocked in such a manner that its removal prevents x-rays from being produced; (b) where it is a stationary machine, a means to prevent the x-ray tube from producing x-rays unless there is an image receptor in place to intercept the x-ray beam; (c) an audible signal that, (i) indicates completion of any preset time of use up to a maximum of five minutes, and (ii) continues to sound until the timer is reset whenever x-rays are produced after the preset time of use has expired, or, a timer circuit that will, (iii) cut off the high tension voltage to the x-ray tube after a preset time of use up to a maximum of five minutes, and (iv) continue to prevent fluoroscopy until the timer has been reset manually; (d) electrical meters or other visual indicators on the control panel that will provide a continuous indication of current in milliamperes; (e) a means to limit the target-to-skin distance to not less than, (i) twenty-five centimetres for a mobile fluoroscopic machine, (ii) thirty-eight centimetres for a stationary fluoroscopic machine, or (iii) twenty centimetres for an image-intensified fluoroscopic machine used for special procedures that would not be possible at the minimum target-to-skin distance set out in subclause (ii); (f) an x-ray beam limiting device that, (i) allows the operator to adjust the dimensions of the x-ray field at the image receptor to a size smaller than the dimensions of the image receptor, and (ii) aligns the x-ray field with the image receptor in such a manner that the x-ray field is always confined within the boundaries of the image receptor; and (g) a shield of at least 0.25 millimetres lead equivalent at 100 kilovolts peak that intercepts scattered radiation originating in the patient that would otherwise reach the x-ray operator or other persons in the facility. R.R.O. 1990, Reg. 543, s. 17 (1); O. Reg. 87/22, s. 7 (1). (2) Clause (1) (b) does not apply to special purpose x-ray tubes or image intensifiers that are constructed to have free and independent movement within an x-ray room. R.R.O. 1990, Reg. 543, s. 17 (2). (3) Clause (1) (g) does not apply to a mobile fluoroscopic x-ray machine. R.R.O. 1990, Reg. 543, s. 17 (3). (4) The exposure rate limit of a fluoroscopic x-ray machine that uses a zinc cadmium sulphide input phosphor or a phosphor of similar efficiency calculated where the centre of the useful beam enters the patient at the shortest target-to-skin distance specified for the machine shall not exceed, (a) a maximum exposure rate of 12.5 roentgens per minute; and (b) an entrance exposure rate of five roentgens per minute for an average patient represented for test purposes by a twenty centimetre water phantom. R.R.O. 1990, Reg. 543, s. 17 (4); O. Reg. 87/22, s. 7 (2). (5) The exposure rate limit of a fluoroscopic x-ray machine that uses a cesium iodide input phosphor or a phosphor of similar efficiency calculated where the centre of the useful beam enters the patient at the shortest target-to-skin distance specified for the machine shall not exceed, (a) a maximum exposure rate of ten roentgens per minute; and (b) an entrance exposure rate of 2.5 roentgens per minute for an average patient represented for test purposes by a twenty centimetre water phantom. R.R.O. 1990, Reg. 543, s. 17 (5). (6) Clauses (4) (a) and (5) (a) do not apply when the high-level control of the x-ray machine is activated. R.R.O. 1990, Reg. 543, s. 17 (6). (7) A fluoroscopic x-ray machine that is equipped with an optional high-level control that allows higher exposure rates at the image receptor than the rates set out in subsections (4) and (5) shall be so constructed that, (a) the high-level control is activated by its own control separate from any other control; and (b) there is a continuous signal to the x-ray operator to indicate that the high-level control is being activated. R.R.O. 1990, Reg. 543, s. 17 (7). (8) A photofluorographic x-ray machine shall only be used when the primary image is enhanced by electronic image intensification. R.R.O. 1990, Reg. 543, s. 17 (8).