Measures of Deterministic Responses

Deterministic Responses. Prevention of deterministic responses is a basic principle of health protection for both radionuclides and hazardous chemicals the goal is to achieve zero probability of such responses. Incidence is the primary measure of deterministic response for any hazardous substance, although prompt fatalities also are of concern at sufficiently high doses. In risk assessments and in establishing deterministic dose limits, no adjustments are made to take into account, for example, the relative severity of different responses with regard to consequent reductions in the quality of life. 

Measures of Response for Substances Causing Deterministic Responses. For purposes of health protection in routine exposure situations, incidence has been the primary measure of deterministic response for both radionuclides and hazardous chemicals. Fatalities also are of concern for substances that cause deterministic responses, but only at doses substantially above the thresholds for nonfatal responses. Given that the objective of standards for health protection is to prevent the occurrence of deterministic responses, incidence is not modified by any subjective factors that take into account, for example, the relative severity of different nonfatal responses with respect to a diminished quality of life. Judgments about the importance of deterministic responses are applied only in deciding which responses are sufficiently adverse to warrant consideration in setting protection standards. 

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