Exposure limits ionizing radiation

From the National Council on Radiation Protection and Measurements, "Recommendations on Limits for Exposure to Ionizing Radiation," NCRP report No. 91, 7910 Woodmont Ave., Bethesda, MD, June 1987. 

NCRP (1993). National Council on Radiation Protection and Measurements. Limitation of Exposure to Ionizing Radiation, NCRP Report No. 116 (National Council on Radiation Protection and Measurements, Bethesda, Maryland). 

National Council on Radiation Protection and Measurement (1993). Limitation of exposure to ionizing, radiation (NCRP 116). NCRP Publications, Bethesda, MD... 

With such a history, it is not surprising that even medical x-rays and radiotherapy generate fears, sometimes hysteria, about radiation poisoning. No nuclear power stations have been built in the United States since the late 1970s. The existence of a safe radiation dose has been debated for decades without consensus. As one expert puts it, the most practical approach is to limit human exposure to ionizing radiation and hope for the best. 

ALARA Acronym for As Low As Reasonably Achievable, means making every reasonable effort to maintain exposures to ionizing radiation as far below the dose limits as practical, consistent with the purpose for which the licensed activity is undertaken, taking into account the state of technology, the economics of improvements in relation to benefits to the public health and safety, and other societal and socioeconomic considerations, and in... 

It requires exposure to ionizing radiation, which can be especially limiting when multiple occasions of measurement are needed. 

ICRP Publication 1 was adopted in 1958 and was available in the following year. This document gave background for a comprehensive protection system based on the knowledge that "Exposure to ionizing radiation can result in injuries that manifest themselves in an exposed individual and in his descendants these are called somatic and genetic injuries respectively". Essentially the recommended system comprised a dose limitation concept based on "maximum permissible doses" applied to different exposure categories. Probably the best known of diese recommendations is the formula D = 5(N-18), where D is the maximum allowable accumulated dose in rem units and N the age in years. 

The nature of radioactive waste implies in particular the hazard of exposure to ionizing radiation. Other hazards associated with radioactive waste are similar to those associated with toxic waste. In establishing acceptable levels of protection the recommendations of the International Commission on Radiological Protection (ICRP) [5-7] and the IAEA [8] and specifically the concq>ts of justification, optimization and dose limitation are taken into account. The relevance of these concepts depends on the e of radioactive waste management activities. The following exanples may be given ... 

A requirement for the operation of a nuclear power plant is that The operating organization shall establish and implement a programme to ensure that, in all operational states, doses due to exposure to ionizing radiation... in the plant or due to any planned releases of radioactive material from the plant are kept below prescribed limits and as low as reasonably achievable (Ref. [1], para. 8.1). 

Table 11.4 UK exposure limits (the Ionizing Radiations Regulations, 1999)...

Is the employer using means other than employee rotation to eomply with permissible exposure limits (PELs) or ionizing radiation dose limits, exeept where no other feasible way exists [OSHA Referenee. 120(g)(l)(iii)]... 

In developing a risk-based waste classification system, the primary emphasis would be on risk management, rather than estimation of risk for actual exposure situations. However, differences in the state of knowledge of the carcinogenicity of ionizing radiation and chemicals could be taken into account in establishing limits on allowable doses (hypothetical risks) for radionuclides and chemicals to be used in classifying waste. 

Sir Edward Pochin (1978) Why be Quantitative about Radiation Risk Estimates Hymer L. Friedell (1979) Radiation Protection-Concepts and Trade Offs Harold O. Wyckoff (1980) From Quantity of Radiation and Dose to Exposure and Absorbed Dose -An Historical Review James F. Crow (1981) How Well Can We Assess Genetic Risk Not Very Eugene L. Saenger (1982) Ethics, Trade-offs and Medical Radiation Merril Eisenbud (1983) The Human Environment-Past, Present and Future Harald H. Rossi (1984) Limitation and Assessment in Radiation Protection John H. Harley (1985) Truth (and Beauty) in Radiation Measurement Herman P. Schwan (1986) Biological Effects of Non-ionizing Radiations ... 

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