Ozone is a naturally occurring gas made of three oxygen atoms, primarily found in the stratosphere where it forms the ozone layer that absorbs most of the sun’s ultraviolet radiation. Discovered in 1913, the ozone layer is experiencing depletion at a rate of approximately 4% per decade, mainly due to chlorine-containing substances like chlorofluorocarbons (CFCs) from various industrial and consumer products. Ozone depletion has adverse effects on human health, aquatic life, and the environment, leading to increased risks such as eye diseases, skin cancer, and developmental issues in marine species.

2. • It is natural occurring gas found in earth’s
atmosphere.
• It is an allotrope of an oxygen consisting of 3
atoms of oxygen ( O3).
Christian Friedrich Schonbein noticed the
pungent odour and recognized it as the smell
often following a bolt of lightning. In 1839,
he succeeded in isolating the gaseous
chemical and named it "ozone", from the
Greek word ozein meaning "to smell".

3.  About 90% of ozone is found in the layer of the
stratosphere located 10 – 50 km above earth
surface.
This is called the OZONE LAYER .
 It absorb most of the sun’s UV Radiation.
 The ozone layer was discovered in 1913 by the
French physicists Charles Fabry and Henri Buisson

4.  Ozone layer depletion,
is simply the wearing
out (reduction) of the
amount of ozone in
the stratosphere.
 Ozone depletion
describe a steady
decline of about 4%
per decade in the total
volume of ozone in
earth’s stratosphere
the ozone hole.

6.  Catalytic destruction is by atomic halogens. The
main source of these halogen atom is halocarbon,
refrigerants, solvent(chloroform), propellants and
foam blowing agents(HCFCs, halons(firefighting) ,
freon ).
 CFC and many other substance are referred as
ozone depleting substance.
 Chlorofluorocarbons are used in cosmetic,
pressurised blower , heat detectors.
 Carbontetrachloride are used in dry cleaning
sparys,spray adhesive , correction fluid.

7. It was seen in 1970’s by research group from the
British Antarctica Survey(BAS).
 The word hole is in context with ozone the ozone hole
is more correctly described as a low concentration of
ozone.
 The primary causes of ozone depletion is the presence
of chlorine – containing source gases (CFC’s and
related hydrocarbons).

8. Effect on human life
eye diseases ,skin it affect aquatic animals
cancer. Damage early development
of fishes, crab , shrimp.
increased UV rays affect bad effect on non
plants by reducing their living material likpaint
size. Fabric pipes.

9.  .