The signed individuals below are concerned about the damage that excessively conservative dose limits promulgated by regulatory bodies have caused and we are committed to pursue efforts to mitigate that damage. We note that the conference, Applicability of Radiation-Response Models to Low Dose Protection Standards, held in early October 2018 addressed this issue (https://www.lowdoserad.org), and that the ICRP made valuable contributions to the conference. We are especially pleased that the ICRP proposed draft TG93 has come out so soon after the conference.
We have reviewed TG93 and offer the attachment as our perspective of the document. Our perspective is simply a perspective from concerned citizens, and should not be considered a traditional line by line editorial comment.
Applicability of Radiation-Response Models to Low Dose Protection Standards
Conference Committee Perspective on Draft ICRP TG93
Radiological Protection of People and the Environment in the
Event of a Large Nuclear Accident
Steve Baker
Antone Brooks
Ludwig Feinendegen
Wayne Glines
Darrell Fisher
Wanda Munn
Alan Waltar
Gerald Woodcock
The Joint American Nuclear Society/Health Physics Society topical conference Applicability of Radiation-Response Models to Low Dose Protection Standards addressed many topics relevant to the recent ICRP TG93 Draft. We are pleased to give our perspective on the draft.
We note that the draft document builds on the Fukushima Dialogues and prior experience with the Chernobyl accident. We believe that the TG93 technical approach is sound and consistent with the results of the conference. Specifically, we agree that all associated impacts of a radiation exposure event must be dealt with, not just the consequences of radiation dose.
We agree that citizens must be enabled to make informed decisions about their own lives by obtaining the information and technology required to make those decisions competently. We believe that the Fukushima Dialogues should establish a global standard for governments and industry to provide the that technology and information.
We agree that providing numerical values to guide emergency actions is appropriate, but we are concerned that the perspective in which the guidelines are given tends to be lost, resulting in regulatory agencies accepting them as absolute limits that must never be violated.
Recognizing that regulatory bodies often misinterpret “reference levels” as “dose limits,” we suggest that the numerical values in TG93 be presented in a context that encourages better understanding. Please consider adding material suggested by Figure 1 (https://www.lowdoserad.org/Figure1.png) and the introductory text below to the abstract portion of the document to discourage misinterpretation of reference levels.
Health effects from radiation exposure are a continuum: very high levels are fatal, whereas detrimental health effects from very low levels are buried in noise. Exposure values showing green on the graphic below do not let one observe detrimental health effects; exposures showing red should be avoided. Although the ICRP does not currently accept the premise that low-dose/dose-rate exposures might be beneficial, a plethora of scientific data suggest that exposures below the red area can have both beneficial and negative health effects, the ratio of which determines the net-outcome of detriment. These data should be available to affected people to help them make their own decisions with respect to radiation protection and should be considered when responding to specific radiological release situations in which numerical guidance may be exceeded.
Further, we suggest replacing the 1.0 mSv long-term guidance with a range of exposures that overlaps with natural background. We suggest that inclusion of the range indicated by “People living in long-term contaminated areas” is sufficient to make the 1.0 mSv guidance unnecessary.
We recommend modification to the “Main Points” to further help deter misinterpretation of “reference levels.” The second bullet would be strengthened by adding some text from the “optimization” section of the document. Specifically, we suggest adding the following in red to emphasize that reference levels are not dose limits:
The principle of optimisation of protection applied with reference levels, considering all impacts (radiological, non-radiological, social, economic, and environmental), is essential to mitigate the consequences during the emergency response and to improve living conditions in affected areas during the recovery process. The Commission maintains its position that reference levels are not regulatory limits that should not be exceeded, but are values to guide the optimisation process. The best protection option is not usually the one resulting in the lowest residual dose level for individuals.