South Australian Numbered Regulations South Australian Numbered Regulations92—Fixed apparatus used for medical or veterinary diagnostic radiography or by chiropractor
(1) Subject to subregulation (2)
, fixed apparatus that is used for medical or veterinary diagnostic radiography or by a chiropractor, but is not used for fluoroscopy, computed tomography, mammography, or soft tissue radiography must—
(a) if the apparatus had been registered under the revoked Health Act regulations—
(i) comply with the requirements of subregulations (4)
to (7)(a)
, (8)
, (9)
and (12)
; and
(ii) except in the case of a special purpose fixed geometry apparatus, comply with subregulation (3)
; and
(iii) comply with the requirements of either subregulations (10)(a)
and (11)
or subregulation (10)(b)
;
(b) in any other case—comply with the requirements of subregulations (3)
to (18)
.
(2) This regulation does not apply to—
(a) apparatus capable of both fluoroscopy and plain radiography; or
(b) orthopantomographic apparatus.
(3) The X-ray tube must be fitted with a continuously adjustable collimator that—
(a) has a light beam—
(i) the centre of which is indicated; and
(ii) the alignment of which with any boundary of the X-ray beam does not exceed 1% of the distance between the focus of the X-ray tube and the image receptor; and
(b) can be rotated around the centre of the X-ray beam; and
(c) the minimum distance of which between the focal spot and the patient's entrance surface is 300 millimetres.
(4) If X-ray tube potential, current or exposure time—
(a) are capable of being varied, control settings must be provided on the control panel so that the required value of tube potential, current and exposure time or a combination thereof can be set without a trial exposure being made; or
(b) are not capable of being varied, the values of that potential, current or exposure time must be indicated on the control panel.
(5) The half value layer of the primary beam must, for every available kilovoltage, be not less than the value of half value layer shown in the table set out in Schedule 8
as being appropriate to the selected kilovoltage.
(6) The apparatus must be fitted with a device that will terminate the exposure after a preset—
(a) time interval; or
(b) product of tube current and time; or
(c) programmed exposure.
(7) The exposure switch fitted to the apparatus must—
(a) have a circuit closing contact that—
(i) can be maintained only by continuous pressure; and
(ii) makes it impossible to make repeat exposures without releasing the switch; and
(iii) in the case of programmed exposures—makes it possible to interrupt the exposure at any stage of the programme; and
(b) not be operable in parallel with any other exposure switch.
(8) The X-ray tube housing must be supported so that it remains stationary when placed in position for plain radiography.
(9) The apparatus must produce a consistent, linear radiation output so that—
(a) the coefficient of variation of at least 5 measurements of radiation output taken at the same exposure settings must be less than or equal to 0.05; and
(b) the coefficient of variation of at least 5 values of the ratio of radiation output to charge, where the radiation output is measured at a fixed kilovoltage and the charge is that indicated on the control panel and is varied from measurement to measurement, must be less than or equal to 0.1.
(10) The apparatus must incorporate a device that provides a warning to the operator whenever the tube is energised, being a warning that consists of—
(a) a clearly distinguishable red or amber light; and
(b) an audible signal that is audible at the location from which the equipment is operated and indicates either the duration or termination of the exposure.
(11) If the apparatus does not have the audible signal referred to in subregulation (10)
it must not have an indicator light on the control panel that is the same colour as the light referred to in that subregulation.
(12) The apparatus must have a readily accessible mains switch to control the supply of mains power to the apparatus and a mains indicator light to indicate when the control panel is energised and the mains switch is in the "ON" position.
(13) The X-ray tube must be enclosed in a housing so that the equivalent dose rate from leakage radiation at a distance of 1 metre from the focus of that tube does not exceed 1 millisievert in 1 hour at each rating specified by the manufacturer for that tube in that housing and, in order to determine compliance with this requirement, measurements must be made over an area not larger than 10 000 square millimetres at a distance of 1 metre from that tube.
(14) Any diaphragm, cone or collimator used to limit the useful beam to the area of clinical interest must be so constructed that, in combination with the tube housing, it complies with the leakage radiation limits set out in subregulation (13)
.
(15) A continuously adjustable collimator fitted to an X-ray tube must—
(a) have a light beam the illuminance of which is not less than 100 lux at a distance of 1 metre from the light source; and
(b) where provision is made for the automatic adjustment of the size of the irradiated area—be fitted with a manual override that permits the selection of a smaller area.
(16) If more than 1 X-ray tube can be operated from a single control panel, except in the case of diagnostic X-ray apparatus specifically designed for 2 tube techniques, it must not be possible to energise more than 1 X-ray tube at the same time and there must be an indication showing which X-ray tube is selected—
(a) on the control panel; and
(b) except in the case of the undertable and associated overtable X-ray tubes on fluoroscopic apparatus—at or near the tube housing.
(17) If an apparatus is fitted with an automatic exposure control—
(a) the selection of the control must, when it takes place, be clearly indicated on the control panel; and
(i) the exposure time to no more than 6 seconds; or
(ii) the product of the tube current selected and exposure time delivered to no more than 600 milli-ampere seconds; and
(c) where an exposure has been terminated after the period referred to in paragraph (b)
—a visible or audible signal must indicate that termination has occurred and manual resetting of the control must then be required before further automatically timed exposures can be made.
(18) The position of the focal spot must be clearly indicated on the tube housing.