the term "action level" is recommended. In general it
will be appropriate to institute countermeasures only
when their social cost and risk will be less than those resulting
from the exposure. Setting of action levels is the responsibility
of national authorities.
It is not desirable to expose members of the public to doses as
high as those considered to be acceptable for radiation workers
because children are involved, members of the public do not
make the choice to be exposed, and members of the public are
not subject to selection, supervision and monitoring, and are
exposed to the risks of their own occupations. For planning
purposes, dose limits for members of the public are seta
factor of ten below those for radiation workers.
The ICRP dose limits for individual members of the public are
presented in Table II. No maximum ''somatically significant"
dose for a populationis given. The genetic dose to the population
should be kept to the minimum amount consistent with necessity
and should not exceed 5 remms in 30 years from all sources other
than natural background and medical procedures.
No single type
of population exposure should take up a disproportionate share
of the total of the recommended dose limit.
TABLE I
ICRP DOSE uimits 1/
Individuals
Population
Gonads, red
0.5 rem/yr
-
Skin, bone,
thyroid
3.0 rems/yr 2/
-
Hands and forearms;
7.5 rems/yr
-
Other single organs
1.5 rems/yr
-
bone-marrow
feet and ankles
Genetic dose 3/
-
5 rerns/30 yrs
1/ For conditions and qualifications see ICRP Publication 9.
2/ 1.5 rems/yr to thyroid of children up to 16 years of age.
3/ See paragraphs 84, 85, and 86, ICRP Publication 9.
Hi-4