The Variation of Concepts and
Recommendations on Riadiation
Protection
Reference:
C.G. Jones, A Review of the History of U.S. Radiation
Protection Regulations, Recommendations, and Standards, Health Physics, Vol.88 No2, p105-124,2005
制 作：张立国
22/03/2005
2005-3-22
Health Physics Seminar Heallth Physics
Seminar
1
● Introduction
■ History:
■ X-ray, Roentgen,1896
■ Radium, Becquerel, Marie & Pierre Curie, 1901
■ Harm:
■
■
X-ray, sterility(不孕)，bone disease，cancer,1911
Radium, serious illness and death, female factory
workers, Harrison S. Martland, 1925
■ State: No standardized Methods for measurement
of radiation exposure or calculation of radiation
dose.
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● Early Recommendations (19281945)
■ Organization:
■
■
International Advisory Committee on X-ray and Radium
Protection,1928,---ICRP
National (….),NCRP,1929
■ Concepts:
■
■
X-ray: tolerance dose, 0.2R(roentgen) per day,High-energy
photons (international&national)
Radium: body burdens (National…), 0.1  C i, internal
exposure
■
■
■
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ICRP, NCRP, bone seeking radionuclides
To limit the exposure of radiological workers to levels that
result in no visible effects
Concepts and techniques for assessing radiation dose is in
its infancy.
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● Development of Radiation
Protection Recommendations (1945-1959)
■ Organization:
■
■
■
■
■
NCRP,1946; ICRP(?)
AEC,Atomic Energy Commission, 1946 (Truman)
BEAR:Biological Effects of Atomic Radiation,1956
IAEA:International Atomic Energy Agenccy,1957
UNSCEAR:United Nation Scientific Committee on
the Effects of Atomic Radiation,1958
■ Debate concerning radiation philosophy
■
■
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BEAR(1956) genetic effects “as low as possible"
Permissible dose vs. Tolerance dose
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● Development of Radiation
Protection Recommendations (1945-1959)
■ Changes in Recommendations:
■
■
■
■
Decrease of the permissible dose
Dose limit to critical organs.
Exposure limit for the public (1/10 of the workers,
1954)
Special units of Radiation Measurement
■
■
■
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rad:describes absorbed dose to 100ergs per gram
of human tissue
rem:reontgen equivalent man
Concepts for internal models
Health Physics Seminar
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● Congressional Interest and Formulation of
the Federal Radiation Council and NCRP
(1959-1974)
■ Organization:
■
■
■
FRC: Federal Radiation Council,1959
NCRP: National Council of Radiation Protection and
Measurement,1964
EPA: Environmental Protection Agency,1970
■ Knowledge:
■
■
■
■
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1960,RPGs,FRC,Radon in uranium mines, WL,WLM
1968,FDA,radiation from machines
1971,AEC,as low as practicable --> ALARA
1972, BEIR,BEIRⅠ,No dose threshold with respect to
low dose response
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●A New Regulatory Era (1974 to Present)
■ ICRP Publication 26 ---Risk based system
■
Principles:
Justification of practices
■ Optimization of doses
■ Limitation of risk
Concepts
■ Effective dose equivalent (combine internal and external
exposure)
■ Stochastic effect: departure from threshold effect
(deterministic effect)
■ Linear hypothesis
■ Risk factors (use to derive dose limits from a limit on
annual risk.)
■
■
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∙A New Regulatory Era(1974 to present)
■ ICRP Publication 60,1991
■ Still embraces the concept of
■ Optimization, Justification, Limitation
■ Effective Dose and Equivalent Dose
■ Quality factor (Q)  Radiation weighting factor
■
(WR)
Reduction of dose limit:
■
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For radiological workers:(50mS-->20mSv) per
year.
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