The Ionising Radiations Regulations 1999 (IRR99) places a requirement on manufacturers etc to ensure that any article for use in work with ionising radiations is so designed and constructed as to restrict, so far as is reasonably practicable, the extent to which employees and other persons are, or are likely to be, exposed to ionising radiation.
The IRR99 guidance states that “All people involved in the chain from the design, manufacture and supply to the use or installation of an article have a responsibility to ensure that unambiguous and comprehensive information is passed along that chain. Only then can the user know precisely how the article should be used so that standards for restricting exposures can be maintained or improved commensurate with the article performing the function for which it was intended.
Sometimes a commercially available article that was neither designed for use in connection with work with ionising radiation, nor sold by the supplier for that purpose, is nevertheless used as such by a radiation employer. Unless an article has been supplied on the basis of its future use or its design criteria, the radiation employer will want to ensure that it complies with IRR99 and achieves the necessary performance stated.”
The Ionising Radiations Regulations 1999 (IRR99) places a requirement on any installer or erector of an article for use at work, being work with ionising radiation, to undertake, where appropriate, a critical examination of the way in which the article was erected or installed for the purpose of ensuring, in particular, that:
- The safety features and warning devices operate correctly; and
- There is sufficient protection for persons from exposure to ionising radiation; and
- The article operates as intended (i.e. as designed).
The Ionising Radiations Regulations 1999 (IRR99) places a requirement on the installer or erector to consult with the radiation protection adviser (RPA) appointed by himself, or by the radiation employer (where the article is being installed) with regard to the nature, scope and extent of any critical examination and the results of that examination. It is always appropriate to carry out a critical examination if there may be radiation protection implication arising from the way in which an article is being or has been erected or installed.
The critical examination should test the article under the most extreme conditions likely to be encountered in normal usage and check that all safety features, shielding, interlocks, signs and signals are operative and in place. This requirement for testing applies only to those aspects of the equipment that have a bearing upon radiological protection.
Other articles which may form part of a plant should also be covered by a critical examination and this should take into account matters such as shielding, ease of decontamination of surfaces, containment and other aspects of radiological protection.
Critical examinations are required for various kinds of articles, for example articles containing radioactive substances, x-ray generators, veterinary x-ray units, security x-ray scanners, glovebags/boxes for working with loose radioactive materials, facilities processing/handling/storing radioactive materials, etc.
Critical examinations may be carried out following erection or installation, during commissioning, or as part of trials prior to normal use, and may require co-operation between the various employers involved at each stage of a complex installation.
The duty to ensure that the critical examination is carried out rests with the employer who erects or installs the article, not the user. The critical examination requirement not only applies to new articles or equipment but also to second hand or refurbished items/plant and a critical examination is also required if existing articles of equipment are relocated (including within the same premises).
The installer or erector should also provide the employer (who will use the article) with:
- Adequate information about its proper use;
- The routine testing and maintenance required; and
- A written record of the critical examination.
In cases where the design intent of an article was for work other than for ionising radiations applications, then unless specific contractual arrangements have been made regarding suitability, the responsibility for testing will reside with the employer who is the customer, rather than the supplier. One example would be an extractor fan bought merely as a fan of known capacity from a retailer and then incorporated into a ventilation system intended to control airborne radioactive substances.
RP Alba Ltd can assist with advising on the performance of the critical examinations or can be contracted to perform the critical examination on your behalf and produce a formal critical examination report.
Please contact us if you require any support on any aspects of critical examinations or providing adequate information to the end users of the equipment or articles.