8. ELECTROMAGNETIC RADIATION
• X-rays
• Gamma rays
- Both have short wave length
- Have deep penetrating property
- X-rays are manmade; gamma is produced
during disintegration
- Otherwise both has no material difference
• Cosmic rays also containing ionoizing radiation
9. CORPUSCULAR RADIATION
• Alpha particles
10 times harmful than X-rays
less penetrating force
dangerous if enters body
• Beta particles
• Protons
10. NON IONISING RADIATION
• Ultra violet radiation
• Visible light
• Infrared radiation
• Microwave radiation
• Radio frequency radiation
11.
12. RADIATION UNIT
• Becquerel(Bq):
-Measurement of nuclear activity
• Roentgen:
-Measurement of potency
-other Rad,Rem
• These are now replaced by SI unit:
a) Coloumb/kg
b) Gray
c) Sievert
13. BIOLOGICAL EFFECTS
• Two types :
- short term
- long term
• Acute radiation syndrome
• Effect of ionising radiation :
- somatic – immediate/delayed
- genetic
14. BIOLOGICAL RESPONSE
RADIATION
(rad)
EFFECTS
<5 no immediate observable effect
5-50 slight blood change may be detected
50-150 symptom of nausea, fatigue,vomiting,etc.,
150-1100 severe blood changes,symptoms appear
immediately
1100-2000 the probability of death increases to 100% within
1-2 weeks
>2000 death is certainity
>5000 CNS can no longer control body ; death is for
sure; only supportive care can be given
15. RADIATION PROTECTION
• Max permissible radiation received
from outer space is to be 0.1 rad/year
• Max permissible radiation received
from man made is to be 5 rad/year
• Other precautions include….
