Title 10, Part 20, of the Code of Federal Regulations (10 CFR Part 20), “Standards for Protection Against Radiation,” establishes the dose limits for radiation workers. The limits vary depending on the affected part of the body. The annual total for the whole body is 5,000 mrem.
|Organ, tissue||Occupational Dose Limits||Non-occupational Dose Limits|
|Lense of the eye||15,000||150||NA||NA|
|Shallow dose (skin and extremities)||50,000||500||NA||NA|
The whole-body dose limit is assumed to be at the deep-dose equivalent (a tissue depth of 1 cm).
The lens dose equivalent is the dose equivalent to the lens of the eye from an external source of ionizing radiation at a tissue depth of 0.3 cm.
The shallow-dose equivalent is the external dose to the skin of the whole-body or extremities from an external source of ionizing radiation at a tissue depth of 0.007 cm averaged over and area of 10 cm2.
Stanford Health Physics also ensures that radiation exposure to members of the public and non-occupational workers do not exceed regulated dose limits. The dose limit to non-occupational workers and members of the public are set at two percent of the annual occupational dose limit. Therefore, exposure to a non-radiation worker must not exceed 100 mrem/year. This exposure would be in addition to the annual background radiation.