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In the 1990 Recommendations of the International Commission on Radiological Protection (ICRP Publication No. 60), the recommended dose limits for exposure associated with practice are as follows:
| Dose limits(1) |
|
Application |
Persons employed in radiation work |
Public |
| Whole body effective dose |
20 mSv per year, averaged over defined
periods of 5 years.
Not exceed 50 mSv in any single year(2) |
1 mSv per year(3) |
|
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| the lens of the eye |
150 mSv |
15 mSv |
| the skin(4) |
500 mSv |
50 mSv |
| the hands and feet |
500 mSv |
- |
| (1) |
The limits apply to the sum of the relevant doses from external exposure in the specified period and the 50-year committed dose (to age 70 years for children) from intakes in the same period. |
| (2) |
Additional restrictions apply to the occupational exposure of pregnant women. |
| (3) |
In special circumstances, a higher value of effective dose could be allowed in a single year, provided that the average over 5 years does not exceed 1 mSv per year. |
| (4) |
The limitation on the effective dose provides sufficient protection for the skin against stochastic effects. An additional limit is needed for localized exposures in order to prevent deterministic effects. |
Dose limits stipulated in the Laws of Hong Kong are as follows:
| Dose limits |
|
Application |
Persons employed in radiation work |
Public |
| Whole body effective dose |
20 mSv per year (1) |
1 mSv per year |
|
|
| the lens of the eye |
150 mSv |
- |
| the skin(2) |
500 mSv |
- |
| the hands and feet |
500 mSv |
- |
| (1) |
In the case of the abdomen of a woman with reproductive capacity, 5 mSv in any consecutive 3 months interval; and in the case of a pregnant woman, 1 mSv to the fetus during the pregnancy of the woman. |
| (2) |
For area of skin averaged over any 1 cm2. |
For detail information, please refer to Radiation Ordinance (Chapter 303) in the Laws of Hong Kong. |
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