COMMUNITY MED

1. RADIATION
BY
SUDARSAN

2. SOURCE OF RADIATION
• Radiation is the part of man’s
environment.
• Divided into two groups :
- natural
- man made

3. NATURAL
• Cosmic rays
• Environmental
- terrestrial
- atmospheric
• Internal
- potassium 40
- carbon 14

4. MAN MADE
• Medical
- X-rays
- Radio isotope
• Occupational exposure
• Nuclear
- Radioactive fallout
• Miscellaneous
- TV sets
- radioactive dial watches
- luminous markers
- isotope tagged products

5. PHOTO CORNER

7. TYPES
Radiation
Ionising Non-ionising
electromagnetic corpuscular

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

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….

17. JUST FOR FUN…

18. THANK U