Ionising & non ionising radiation

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

8. 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.

9. 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.

10. 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.

11. NON-IONIZING RADIATION N on-ionizing radiation can cause injury to humans but the injury is generally limited to thermal damage i.e. burns.

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

13. 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.

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

15. 2 & 3. RADIOFREQUENCY AND MICROWAVE FREQUENCY EXPOSURES Occupational exposures- r adar 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) .

16. 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.

17. 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

18. 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.

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

20. 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.

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

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

23. 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.

24. 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 10 7 m/s

25. 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

26. 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.

27. 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

28. 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.

29. Alpha particles can be stopped by paper, Beta by plastic .

30. 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.

31. 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.

32. THANK YOU