Facility Design
Radiological Council approval is required for the design of facilities where irradiating apparatus, lasers and radioactive substances are intended to be used. Depending on the type of radiation source, consideration of structural radiation protection (radiation shielding), ventilation, plumbing and finishings may be required.
The design of facilities must ensure that the Council's design dose constraints of 10% of the occupational and 50% of the public annual effective dose limits (2 mSv and 0.5 mSv respectively) are not exceeded. For some operations (such as mining and environmental), a lower dose constraint of 30% of the public annual effective dose limit (0.3 mSv) will need to be applied.
Appropriately experienced private radiation consultants may advise the owner on facility design and radiation protection in accordance with the WA requirements. However, the Radiological Council must approve the facility design and confirm any advice given by consultants before the irradiating apparatus, lasers and radioactive substances may be registered for use.
The requirements specific to common uses of radiation are addressed below.
Structural radiation protection (radiation shielding) assessments are required to be undertaken for most x-ray equipment facilities.
Enclosed x-ray apparatus (including x-ray analysis, special purpose enclosed and cabinet x-ray equipment installations) do not require radiation shielding assessments for the room. However, the equipment is required to meet the surface dose-rate constraints, warnings, signage and interlock requirements detailed in the relevant equipment Code/Standards.
Handheld and portable equipment used at field sites do not require radiation shielding assessments for the location in which they are used.
Industrial X-ray Facilities
For non-enclosed apparatus, a radiation shielding assessment will need to be conducted for the area in which the x-ray equipment is installed or operated. Equipment that fits into this category includes industrial radiography bunkers, CT equipment and linear accelerators used for industrial purposes.
Diagnostic X-ray Facilities
Medical, dental and veterinary installations will require radiation shielding assessments for the room/s in which the x-ray equipment will be used.
Dental (other than Cone Beam CT), Mammography and Bone Densitometry
Diagnostic X-ray Equipment - Fixed and Mobile
Radiotherapy Facilities
A report detailing the suitability of each radiotherapy treatment room's design and radiation shielding properties, as afforded by the construction of the room, must be submitted to the Radiological Council for review. The report must be signed off by two radiation oncology medical physicists accredited as such with the Australasian College of Physical Scientists and Engineers in Medicine.
Following construction of the treatment room, the following must also be submitted to Council –
- a report from a structural engineer confirming the structural design of the treatment facility, in accordance with the approved plans; and
- confirmation of a radiation survey of relevant accessible areas in and immediately around the treatment room, which confirm the level of required shielding.
Sealed Radioactive Substances
Structural radiation protection (radiation shielding) assessments may be required to be undertaken for facilities using sealed radioactive substances. Exposure bays used for industrial radiography will require a shielding assessment.
Sealed radioactive substances contained in a self-shielded device (e.g. industrial gauges) do not require radiation shielding assessments for the area in which they are used; however, the device is required to meet the surface dose-rate constraints detailed in the relevant Code/Standard.
Sealed radioactive substances used for calibration or demonstration purposes also do not require radiation shielding assessments; these sources are generally of sufficiently low activity that local shielding at the source (storing in a shielded container) will provide adequate radiation shielding.
Unsealed Radioactive Substances
Unsealed radioisotope laboratories and nuclear medicine facilities will be required to have the facilities radiation shielding, ventilation, plumbing and finishings assessed.
Facilities where Class 3B and Class 4 lasers are used will need to meet the room design requirements specified in the Radiation Safety (General) Regulations 1983 unless advised otherwise by the Radiological Council.