FREQUENTLY ASKED QUESTIONS |
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Biological Effects of Radiation in Man : |
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The effects of nuclear radiation in man are due to its energy absorbed in verious tissue, which is called dose. The effects depend on dose absorbed, the rate at which it is absorbed, type of radiation, strength of radiation & type of tissue.
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Dose Limits : |
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Dose Limits Recommended by ICRP(1991):
Application |
Dose limit |
|
Occupational |
Public |
Whole Body: |
20mSv (2R) per year,
averaged over a defined period of 5 Yrs., with not more than 50mSv(5R) in a single year |
1mSv(100mR)
in a year, averaged over 5 years |
Parts of body(equivalent dose): |
|
|
Lense of the
Eye |
10mSv(15R) per year |
15mSv(1.5R) in
a year |
Skin* |
500mSv(50R) per year |
50mSv(5R) in a year |
Hands & Feet |
500mSv (50R) per year |
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*Averaged over areas of no more than 1cm2 regardless of the area exposed. |
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Note: Absorbed dose is measured in Gy or rad (1G = 100rad) & tissue equivalent absorbed dose is measured in Sv
or rem (1Sv = 100rem). However, in case of c / g radiation ,
practically there is not much difference between R, Rad & Rem for tissues. So for understanding purpose, above data is given in R with 1Gy= 100R,
an approximate relation.
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