ppt

1. IONISING & NON IONISING
RADIATION
BY DR ATMARAM CHOUDHARI
Govt. Medical college Nagpur

2. matter
• matter is anything that has mass and takes up
space.
• Particles-
are tiny bits of matter that make up
everything in the universe.
Types- 1. Macroscopic particles.
2. microscopic particles.
3. Subatomic particles.

3. • 1. Macroscopic particles - larger
than atoms or molecules.
They have volume and shape.
Powder and dust are some examples of
macroscopic particles.

4. 2. microscopic particles.
• Atoms and molecules are called microscopic
particles.
3. Subatomic particles -particles that are
smaller than atoms.
The proton, the neutron, and
the electron are subatomic particles.

5. Elements
• Elements are chemically the simplest
substances and hence cannot be broken down
using chemical reactions.

6. MOLECULES

7. EXAMPLES OF MOLECULES

9. Radiation
• Radiation is basically energy travelling as wave
or particles.
• Energy emitted from a body or source that is
transmitted through an intervening medium
or space and absorbed by another body.

10. • Radiation is classified as being either non-
ionizing or ionizing.
• Non-ionizing radiation is longer wavelength
/lower frequency lower energy.
• While ionizing radiation is short
wavelength/high frequency higher energy.

11. IONIZING RADIATION
• Ionizing Radiation has sufficient energy to
produce ions in matter at the molecular level.
• If that matter is a human significant damage
can result including damage to DNA and
denaturation of proteins.

12. NON-IONIZING RADIATION
• Non-ionizing radiation can cause injury to
humans but the injury is generally limited to
thermal damage i.e. burns.

14. • visible spectrum is essentially the divide
between ionizing and non-ionizing radiation.
• As UV radiation risk factor for causing skin
cancer.

15. TYPES OF NON-IONIZING RADIATION
AND THEIR CLINICAL EFFECTS
1. ELF (extremely low frequency).
2. Radio Frequencies.
3. Microwave Frequencies.
4. Lasers.
5. Infrared.
6. Visible Spectrum.
7. Ultraviolet.

16. 1.ELF (extremely low frequency).
• Power plant
• line workers have Inconclusive evidence of
leukemia link.

17. 2 & 3. RADIOFREQUENCY AND
MICROWAVE FREQUENCY EXPOSURES
• Occupational exposures-
radar and communications equipment,
industrial and commercial ovens
• Other Exposures-
Cell Phones 5G cancerous?
Wi- fi 2.5or 4 hz band
frequency 2g 3g 4g- 700 Mhz-3ghtz.
5g mm wave freq. 300ghtz radiation ? IARC
International agency for research on cancer 2011
radio frequency waves possibly carcinogenic (limited
evidence) .

19. • Clinical Effects-
There is a controversy of regarding
potential cancer risks, with cell phone
use.
• Exposure to radio and microwave frequency
sources can cause burns and clinically seen.

20. 4.LASER
• (Light Amplification by Stimulated Emission of
Radiation).
• Beams of coherent light with single
wavelength and frequency.
• May be in the IR, Visible or UV spectrum.
• Eye is most sensitive to injury from LASER

21. 5. INFRARED
• Penetrates superficial layers of the skin,
causes thermal injury, potential for damage to
the cornea, iris, lens of the eye.
• Welding, glassmaking, heating and
dehydrating processes.

22. 6. Visible Spectrum
• 400 to 750nm wavelengths.
• VIBGYOR.
• Possibility of retinal injury from 400-500 nm
blue frequencies.

23. 8. ULTRAVIOLET RADIATION
• 200nm to 400 nm.
• Bridge between Non-Ionizing and Ionizing
Radiation.
• Three regions
UV-A 315nm-400nm
UV-B 280nm-315nm
UV-C less than 280nm.

24. • A and B bands produce biologic effects on the
skin and the eyes.
• Photo keratitis, conjunctivitis, sunburn,
photosensitization reactions, skin cancers.

25. • exposures include welders, who work in
drying and curing industries and laboratory,
kitchen or medical industries exposed to
germicidal ultraviolet .

26. TYPES OF IONIZING RADIATION AND
THEIR CLINICAL EFFECTS
• Ionizing radiation is emitted from radioactive
atomic structures as high energy electromagnetic
waves (gamma and x-rays) or as actual particles
(alpha, beta, neutrons).
1. Gamma Rays.
2. X-Rays .
3. Alpha Particles.
4. Beta Particles.
5. Neutrons.

27. Alpha Particles
• 2p+ 2n = helium nucleus
• It has highest charge so
• Maximum ionizing power as compare to alpha
Beta gamma rays.
Least penetrating power as its heaviest particle
mass is 4 amu.
Speed is equals to 107 m/s

28. Beta Particles.
• Its electron.
• symbol e−or β−.
• charge -1
• Mass approx. zero .
• Rest electron mass is 9.1 × 10-31 kilograms.
• Mass of beta particles is undefined

29. • As its fast moving electron so mass will vary
( Einstein s mass energy relation).
• Speed – approx. speed of light 2.5 ×10^8 ms¹ .
• Penetrating power more than alpha but less
than gamma.
• Ionizing power less than alpha but more than
gamma.

30. Gamma rays
• Nothing but energy
• Light
• Wave
• Photon
• It has no charge least ionizing power as compare
to alpha beta .
• no mass so most penetrating power so most
harmful.
• Speed = speed of light i.e 3×10^8 ms-¹

32. PENETRATION OF RADIATION
• Gamma Rays, X rays and Neutrons Penetrate
Body Easily, Need lead to shield for gamma
and x-rays, massive shielding for Neutrons.
• Alpha and Beta Particles are essentially
blocked by the skin with Beta Particles
penetrating more deeply with the potential to
cause burns.

33. • Alpha particles can be stopped by paper, Beta
by plastic .

35. X rays
• This are electromagnetic radiations i.e they
don’t need medium.
• Not visible to human eyes.
• Shorter wavelength and high energy.
• Produced by Roentgen in 1565 in discharge
tube.

36. Difference between x rays and gamma
rays
• Gamma rays cause more harm to human body
than the X- rays.
Gamma rays have shorter wavelengths than the
X-rays.
X rays are emitted by the electrons outside the
nucleus, and gamma rays are emitted by the
excited nucleus itself.
X rays are used in hospitals for taking X-rays but
gamma rays are not.

37. • THANK YOU