The document discusses ozone and ultraviolet radiation. Ozone is a bluish gas composed of three oxygen atoms that is found in the stratosphere, where it absorbs UV radiation and protects the Earth. Ultraviolet radiation is a component of solar energy, and most UV is absorbed by the ozone layer. Depletion of the ozone layer leads to increased UV at the surface, causing health issues like skin cancer and eye damage. Certain man-made chemicals have been found to deplete stratospheric ozone.

1. EGEE 102 - PISUPATI 1

2. OZONE
EGEE 102 - PISUPATI 2
• O3
• a gas composed of three atoms of oxygen
• bluish gas that is harmful to breathe
• Nearly 90% of the Earth's ozone is in the stratosphere
and is referred to as the ozone layer
• Ozone absorbs a band of ultraviolet radiation called
UVB

3. WHAT IS UV?
EGEE 102 - PISUPATI 3
• Ultra Violet radiation is a component of solar energy
• Most solar UV radiation is absorbed by the ozone layer
• More than 36,000 additional cases of eye problems will occur
from ozone depletion
 A and B bands reach the earth, whereas C band is filtered by the
ozone layer. U.V.A penetrate farthest
 Produce physiological effect by non thermal mechanism
 Deepest penetration with high intensity, long wavelength and
lower frequency.

4. ULTRAVIOLET RADIATION
4

5. OZONE IN THE ATMOSPHERE
EGEE 102 - PISUPATI 5

6. EGEE 102 - PISUPATI 6

7. EGEE 102 - PISUPATI 7

8. OZONE-DEPLETING SUBSTANCE(S) (ODS):
EGEE 102 - PISUPATI 8
• CFCs,
• HCFCs,
• halons,
• methyl bromide,
• carbon tetrachloride, and
• methyl chloroform.

9. VARIOUS SOURCES
EGEE 102 - PISUPATI 9

10. EFFECTS OF OLD
EGEE 102 - PISUPATI 10
• -- Skin Cancer (melanoma and non melanoma)
-- Premature aging of the skin and other skin
problems
-- Cataracts and other eye damage
-- Immune system suppression

11. THE ANTARCTIC OZONE HOLE
• The ozone hole is
defined as the area
having less than 220
dobson units (DU) of
ozone in the overhead
column (i.e., between
the ground and
space).
EGEE 102 - PISUPATI 11
Source: http://jwocky.gsfc.nasa.gov/multi/recent_ozone91200.gif

12. EGEE 102 - PISUPATI 12
http://www.cpc.ncep.noaa.gov/products/stratosphere/sbuv2to/ozone_hole_plot.gif

13. WHAT CAN WE DO?
EGEE 102 - PISUPATI 13
• Make sure that technicians working on your car air
conditioner, home air conditioner, or refrigerator are
certified by an EPA approved program to recover the
refrigerant (this is required by law).
• Have your car and home air conditioner units and
refrigerator checked for leaks. When possible, repair
leaky air conditioning units before refilling them.

14. WHAT CAN WE DO?
EGEE 102 - PISUPATI 14
• Contact local authorities to properly dispose of
refrigeration or air conditioning equipment.
• Protect yourself against sunburn. Minimize sun
exposure during midday hours (10 am to 4 pm). Wear
sunglasses, a hat with a wide brim, and protective
clothing with a tight weave. Use a broad spectrum
sunscreen with a sun protection factor (SPF) of at least
15 and 30 is better.

15. EGEE 102 - PISUPATI 15

16. GROUND LEVEL OZONE FORMATION
EGEE 102 - PISUPATI 16
• Secondary Pollutant
• VOCs+ NOx  Ozone
• In presence of sunlight
• Ozone + NOX + HCs  Smog (haze)

17. PHOTOCHEMICAL SMOG
EGEE 102 - PISUPATI 17
NO
CO, RH
NO2
CO
HC
O3
CO
PAN
Haze
6:00AM 12NOON 3:00 PM

18. SMOG SOURCES
EGEE 102 - PISUPATI 18
Source: http://www.epa.gov/oar/oaqps/regusmog/smog.html

19. SOURCES OF VOLATILE ORGANIC CARBONS
EGEE 102 - PISUPATI 19

20. SOURCES OF NOX
EGEE 102 - PISUPATI 20