Many of the recommendations from the ICRP and other groups have been incorporated into the regulatory requirements of countries around the world. In the United States, annual radiation exposure limits are found in Title 10, part 20 of the Code of Federal Regulations, and in equivalent state regulations. For industrial radiographers who generally are not concerned with an intake of radioactive material, the Code sets the annual limit of exposure at the following:- A total effective dose equivalent of 5 rems (0.05 Sv)
or - The sum of the deep-dose equivalent to any individual organ or tissue other than the lens of the eye being equal to 50 rems (0.5 Sv).
2) The annual limits to the lens of the eye, to the skin, and to the extremities, which are:
- A lens dose equivalent of 15 rems (0.15 Sv)
- A shallow-dose equivalent of 50 rems (0.50 Sv) to the skin or to any extremity.
The shallow-dose equivalent is the external dose to the skin of the whole-body or extremities from an external source of ionizing radiation. This value is the dose equivalent at a tissue depth of 0.007 cm averaged over and area of 10 cm2.
The lens dose equivalent is the dose equivalent to the lens of the eye from an external source of ionizing radiation. This value is the dose equivalent at a tissue depth of 0.3 cm.
The deep-dose equivalent is the whole-body dose from an external source of ionizing radiation. This value is the dose equivalent at a tissue depth of 1 cm.
The total effective dose equivalent is the dose equivalent to the whole-body.
The lens dose equivalent is the dose equivalent to the lens of the eye from an external source of ionizing radiation. This value is the dose equivalent at a tissue depth of 0.3 cm.
The deep-dose equivalent is the whole-body dose from an external source of ionizing radiation. This value is the dose equivalent at a tissue depth of 1 cm.
The total effective dose equivalent is the dose equivalent to the whole-body.
Source: http://www.ndt-ed.org/
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