Knowledge Base

Biological Effects of Radiation in Man :

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.

Dose Limits Recommended by ICRP(1991):

Dose Limits :

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

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.