Radiological risk management — elevated risks

As mentioned earlier in this section, a graded approach to risk management is to be used, considering the relevant factors in a deliberative manner. For many situations, the radiation risks are relatively low or reasonably moderate, such that the wording of Sections 5.1–5.3 needs no amplification as regards the development of a protection and safety programme for itinerant workers. Work involving even higher levels of radiation risk may, however, present additional challenges for the facility management and the contractor as protection and safety measures are identified to optimize radiation protection.

The radiation protection staff of the facility and/or the contractor will wish to provide additional management oversight and resources when radiologically significant work is being planned and executed. That focus of resources will

begin when the work evaluation and/or assessment process identifies work where multiple diverse barriers are required to prevent the occurrence of events involving significant accessible radiation fields and/or the potential to exceed applicable individual dose limits or constraints.

Examples may be as follows: (i) known external radiation fields which may result in exceeding preselected values such as 10 mSv/h or 0.5 mSv for a single entry into the work area (or the equivalent for extremities or the lens of the eye);

(ii) entry to areas subject to rapid increases in dose rate due to fixed or mobile sources (such as discrete radioactive particles); (iii) entry to areas where airborne radioactivity concentrations or estimated doses from inhalation are projected to exceed preselected thresholds; or (iv) entry to areas where contamination levels of alpha emitting materials or transuranic materials are projected to exceed preselected thresholds.

As regards the protection of itinerant (and permanent facility) workers, the contractor’s supervisory (and, where applicable, radiation protection) staff, the facility’s supervisory (and, where applicable, radiation protection) staff and, where appropriate, the workers, need to focus collaborative efforts on the following factors:

(a) Designation of a single management or supervisory point of contact by contractor and/or facility to manage the higher risk work; and clarity of the contractual arrangements and local work rules and procedures regarding roles and responsibilities of the task managers of the contractor and facility.

(b) Awareness of job specific risks and their expected and potential magnitudes by planners and work crew personnel.

(c) Decisions regarding any supplemental training that needs to be completed considering the identified risks.

(d) Allocation of resources to identify any appropriate supplemental protection and safety measures during the work planning and work approval processes. For higher risk work, a ‘challenge board’ process may be useful, during which representatives of the contractor and facility from multiple disciplines review and constructively critique work plans as to their adequacy and optimization of protection and safety. Approval of work plans and procedures (including RWPs) by management at more senior levels may also be useful. Such an RWP would specify required controls, criteria requiring immediate cessation of work, and radiation protection monitoring.

(See the description of RWP content in Section 3.4.2.) The process needs to recognize that the organization which is not the registrant or licensee (e.g. the contractor) will likely not be familiar with the procedures used

higher levels of risk awareness and protection and safety controls for work of higher risk. That relative lack of knowledge needs to be addressed by the registrant or licensee providing additional briefings (to the non-registrant/

licensee supervisory staff) on the desirability of using the available techniques for reducing the likelihood of human error by enhancing the numbers of disciplines and the experience levels of personnel represented in the work planning and approval processes.

(e) Allocation of management and/or supervisory resources to pre-job briefings and to continuous oversight of task performance at the work location by the contractor and/or the facility staff, consistent with the warranted higher level of awareness and the need to perform higher risk complex and/or infrequently performed work. The process needs to recognize that the organization which is not the registrant or licensee (e.g. the contractor) will likely not be familiar with the procedures used by the registrant or licensee (e.g. facility management) to both reduce the likelihood of human error and also to provide enhanced means for detecting and correcting such errors. The description of the rationale for the enhanced pre-job briefings and supervisory oversight needs to be explained for the benefit of the non-registrant/licensee staff. Those procedures would include additional communication (between supervisors and craft workers) during pre-job briefings on risks and on risk control measures, including the need for the workers to adhere to the approved local rules and procedures. They would also include provisions for enhanced supervisory oversight of the adherence to local rules and procedures as the work is executed.

(f) Establishment of a team under the auspices of the single point of contact for the work, to perform a post-job assessment of plans and results and, thereby, to specify lessons for the workers, the contractor and the facility.

5.5. SUMMARY

The following statements are intended to summarize the information presented in this section and to reiterate several key concepts described. They need to be interpreted within the context of the entire Safety Report and, specifically, Section 5:

(1) The principal objectives of the RPP are, first, the determination of measures for protection and safety that are optimal for the circumstances, and second, the establishment of means for preventing accidents and for mitigating the consequences of those that do occur [1].

(2) A prior radiological evaluation of the planned work is to be performed, primarily by the registrant or licensee, but in collaboration with the employer of the potentially exposed workers. The results of previous assessments of the same type of work may be used as a basis for the evaluation, if those results remain valid when considering any lessons learned from previous job evalutions and any modifications to the technology and techniques to be incorporated into the planned work.

(3) The radiological evaluation needs to include: (i) an identification of the sources of routine and reasonably foreseeable potential exposures;

(ii) a realistic estimate of the relevant doses and probabilities; and (iii) an identification of the measures needed to optimize radiation protection [7].

(4) The RPP is to be developed based on the prior radiological evaluation and safety assessment, with the registrant or licensee taking the lead role in establishing the programme, but working in collaboration with the employer of the potentially exposed workers. The contractual agreement between the registrant or licensee and the employer will also be a useful reference in developing an RPP which addresses the responsibilities for, and the radiological controls on, the planned work

(5) If the radiological risks of the planned work are relatively elevated, then elevated attention to the development of a comprehensive RPP is warranted.

A principal means of developing an effective RPP is by reducing the possibility of human error or inadvertent action, and providing a means for detecting and correcting such an error if it occurs. To support the sound consideration of human factors, work with relatively elevated risk is most often: (i) managed by a single point of managerial contact; (ii) subject to multidisciplinary review and approval processes during work planning;

and (iii) subject to enhanced pre-job briefings and to enhanced supervisory oversight during job performance.