IAEA EPR-Medical Physicists 2020 – Guidance for Medical Physicists Responding to a Nuclear or Radiological Emergency

IAEA EPR-MED

https://www.iaea.org/publications/13483/guidance-for-medical-physicists-responding-to-a-nuclear-or-radiological-emergency

In the event of a nuclear or radiological emergency hospital medical physicists may find themselves providing front-line response to the event or supporting their hospital’s efforts to triage and treat potentially contaminated casualties.

The objective of this IAEA publication is to guide the trained clinically qualified medical physicists (CQMP[1]) to act appropriately in a nuclear or radiological emergency and ensure that an efficient and coordinated contribution is made to the management of such an emergency. The knowledge of the CQMP can be vital in the preparedness and response to nuclear or radiological emergencies.

The report is accompanied by a pocket guide which summarises most of the concepts given in the full report and is designed as a working aid. But at 78 pages it would require an unusually large pocket. Rather than be an on-the-day aide-memoir the pocket guide covers a lot of preparedness information from the main report. EPR_Pocketbook_web.pdf (iaea.org)

The main report starts with an introduction to emergency planning giving various definitions of emergencies and then a quick overview of the roles the medical physicist might occupy in the local and nation emergency response plans. The noted roles are:

  • Radiological assessor (RA) requiring a qualified expert in radiation dosimetry;
  • Scientific and technical advisor giving advice on matters related to a nuclear or radiological emergency;
  • Trainer in radiation protection providing training within their own clinical environment and, possibly, within and beyond their hospital. During the emergency the trainer will be able to provide quick briefings on radiation protection to the emergency teams.

The medical physicist may serve in a pre-hospital function supporting triage teams and decontamination actions or in the hospital providing advice and training to medical staff.

I think I would have preferred the report to start with what a nuclear or radiological emergency might look like to hospital staff: many people turning, some injured, some contaminated (some both injured and contaminated), many worried well. This may better grab the reader’s attention.

The concept of a scalable incident command system, allowing multi-agency coordination and rapid decision making over a range of scale of event and the medical physicist’s position in the chain of command are discussed. The importance of each player knowing who they report to and to whom they are responsible in a crisis organisation and the understanding that this may not align with normal management is stressed. The diagram given here, cut and pasted from another document, is not helpful. Showing the medical physicist’s position in a chain built round them might have been better.

In section 4, the report runs through the preparedness phase tasks of risk assessment, training, criteria for exposure, potential roles and responsibilities, personal protection and radiation monitoring, procedures for donning protective clothes & monitoring. This section is not a model of clarity and covers material that a medical physicist might be expected to know.

Section 5, which covers activities related to the response, sees the medical physicist implementing the hospital emergency response plan and ensuring that the facility is protected. They will provide briefings on radiological protection and what may occur during the handling of contaminated patients and they will ensure that proper arrangements are followed to minimise the impact on the hospital resulting from the presence of contaminated patients. This section comes with a useful flow chart tracing the possible pathways to treatment for casualties with different combinations of needs, a list of equipment that might be useful and a list of possible actions (including a flow chart showing different actions assigned to different roles in a coordinated manner).

There is also a section labelled the radiological control of areas which is cut from another document and outlines the demarcation of areas for different purposes and the control of people moving through the system to minimise the spread of contamination. Maybe this material should be in the planning section.

Section 6 is entitled early dose magnitude estimation and decontamination. It suggests that accurate dose assessments are unnecessary in the response phase of an emergency; what is needed is a magnitude assessment: is there a problem with either external radiation or contamination that must managed along with the casualty’s clinical needs?

The report discusses how to assess external radiation dose and reviews the gamma ray constant and inverse square law which will probably not be new to many medical physicists. It also mentions a few computer tools such as the Rad Pro Calculator and the Radiation Emergency Medical Management (REMM) dose calculator which are useful to have available.

There are some tables showing how radiation dose can be deduced from observations about which symptoms show and how long after the exposure they show. Versions of these tables should be in the hospital’s emergency data set.

The report suggests that “Internal radiation doses can be extremely complicated to determine” and that “The aim of the assessment of internal contamination is to quantify the incorporation of radioactive material into the body and to estimate the committed effective dose and, where appropriate, the committed equivalent dose to demonstrate compliance with dose limits”. I think that this is appropriate for individual cases of internal contamination following operational mishap but is wrong in the context of responding to a nuclear or radiological emergency. Here the purpose would be to determine what, if any, medical care the casualty might require because of the exposure.

There is a short section on decontamination of casualties. I am sure I have read better.

In the section on the protection of the public (Section 6.2) the report mentions using plume models etc. to estimate deposition levels but gives no clue about how to manage the results. It also talks about determining isodose curves around sealed sources to help the determination of public external exposure.

The collection of excreta for radionuclide analysis is mentioned but no details of the assay methods or reference to dosimetry models used to estimate dose.

After the initial crisis stage there may be a requirement to improve dose estimates. Section 7, which discusses this area has some “key considerations” and some equations but little in the way of practical advice. Maybe following the references quoted may prove more helpful.

In Section 8 it is argued that Medical Physicists should “enhance their communications skills, so that they can contribute to the timely dissemination of relevant information and contribute, all with the response team, in managing individuals and professionals involved in nuclear or radiological emergencies”. You might have thought that these skills, as opposed to speaking to worried members of the public, came with their job.

The psychosocial aspects of nuclear or radiological emergencies gets a sub-section but this does little more than point to further references.

The rest of the section is a very brief overview of communications skills.

Section 9 is a more helpful section on the contents of a “grab and go” bag. This includes dosimeters (EPD and badges), survey instruments, protective equipment, data sheets and forms and miscellaneous tools.

Section 10 gives a very detailed suggested syllabus for training medical physicists and reading lists which are predominantly IAEA publications and would need a fairly large bookshelf to hold and some considerable time to read.

Appendices provide more detailed advice on reception area layout, tags and forms and summary of OILs and reactions to their exceedance.

This is a potentially useful document for hospitals when considering their plans to cope with a nuclear or radiological emergency and considering how to use their radiation specialists. However, it is not only very uneven in the level of detail given but also does not seem to have considered what skills and knowledge the radiation specialist already has and where they might need some training.

It could be better.

[1] See IAEA Human Health Series No. 25, “Roles and Responsibilities, and Education and Training Requirements for Clinically Qualified Medical Physicists”

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