Tools for Placing the Radiological Health Hazard in Perspective Following a Severe Emergency at a Light Water Reactor (LWR) or Its Spent Fuel Pool

Abstract

Experience from past nuclear and radiological emergencies shows that placing the radiological health hazard in perspective and having a definition of "safe" are required in order to prevent members of the public, those responsible for protecting the public (i.e., decision makers), and others from taking inappropriate and damaging actions that are not justified based on the radiological health hazard. The principle concerns of the public during a severe nuclear power plant or spent fuel pool emergency are "Am I safe?" and "What should I do to be safe?" However, these questions have not been answered to the satisfaction of the public, despite various protective actions being implemented to ensure their safety. Instead, calculated doses or various measured quantities (e.g., ambient dose rate or radionuclide concentrations) are used to describe the situation to the public without placing them into perspective in terms of the possible radiological health hazard, or if they have, it has been done incorrectly. This has contributed to members of the public taking actions that do more harm than good in the belief that they are protecting themselves. Based on established international guidance, this paper provides a definition of "safe" for the radiological health hazard for use in nuclear or radiological emergencies and a system for putting the radiological health hazard in perspective for quantities most commonly measured after a release resulting from a severe emergency at a light water reactor or its spent fuel pool.

Saving Lives and Preventing Injuries From Unjustified Protective Actions—Method for Developing a Comprehensive Public Protective Action Strategy for a Severe NPP Emergency

“…The meaningful radiation induced health hazards indicated for selected environmental measurements and exposure situations are summarized in Table 5. The basis for these hazards is described in (IAEA 2013a;McKenna et al 2015) § § §.…”

“…As demonstrated above, protective actions have been taken during severe NPP emergences to avert exposures that were not meaningful since the hazards of radiation exposure were not placed in perspective by the existing guidance. Consequently, a color-coded system to place in perspective the meaningful radiation health hazards for a severe NPP release has been developed (McKenna et al 2015) in order to help decision makers and the public make informed decisions on protective actions. The system is presented in Table 2 and was designed recognizing that dose estimates by themselves are meaningless and are only useful as an indicator of the possible health effects if compared to doses calculated for a specific set of circumstances (IAEA 2013a) ‡ ‡.…”

“…In addition to exposure related health effects, nuclear and radiological emergencies have resulted in adverse economic, social, and psychological effects (IAEA et al 2005;WHO 2013WHO , 2016 and the public, decision makers and others (e.g. medical staff) have taken inappropriate and damaging actions that are not justified based on the radiological health hazard, often in the misguided belief that they were protecting themselves and their families (IAEA 2013a;ICRP 2012;McKenna et al 2015). This was due in part to the failure to communicate the health hazards of radiation exposure clearly and compounded by a complex system of radiation protection concepts and units (IAEA 2013a;ICRP 2012;McKenna et al 2015) that does not provide information on when radiation induced health effects would be meaningful.…”

Lessons Learned in Protection of the Public for the Accident at the Fukushima Daiichi Nuclear Power Plant

“…It should be emphasized that, for many severe accidents, the use of projections of off-site doses based on estimated releases from the NPP would not be effective in deciding on initial urgent protective actions (Homma et al 2015;McKenna 2000). This is because the timing, size and composition of any release would not be predictable, and in order to be effective, the off-site protective actions, in most cases, must be taken before, or shortly after, the release occurs (AESJ 2015;IAEA et al 2011;NRC 2012).…”

“…The public was provided with technical terms such as dose rates, radionuclide concentrations or doses. In many of these cases, the quantities and doses were: (a) used incorrectly, and (b) not placed into perspective in terms of the possible health hazard from radiation (McKenna et al 2015). This failure to clearly communicate to the public how protective actions ensure their safety and the possible health hazards, resulted in inappropriate and damaging actions that were not justified based on the radiological hazard (Hamada et al , NAIIC 2012, Tanigawa et al 2012, Vano et al 2011.…”