Environmental hazards can be categorized as chemical, physical, biological, or psychosocial. Chemical hazards include accidental chemical releases from industrial facilities that can harm human health or the environment. Physical hazards refer to workplace dangers such as unguarded machinery, excessive noise levels, or falls. Biological hazards are biological agents like microbes, viruses, or toxins that threaten human health. Psychosocial hazards impact mental well-being and can overwhelm individual coping abilities. Major environmental disasters caused by humans include nuclear accidents like Chernobyl, industrial accidents like the Bhopal gas leak, and oil spills like the 2010 BP Gulf of Mexico spill.

1. ENVIRONMENTAL HAZARDS &
DISASTERS
• HAZARDS:- A Hazard is a situation that
poses a level of threat of life, Health,
Property or Environment.
• A Environmental Hazard is an event
which has the potential to threaten the
surrounding natural environment or
adversely affect people’s health,
including pollution and natural disasters
such as storms and earthquakes.

5. TYPES OF HAZARDS
• Hazards can be categorized in four
types:
1. Chemical Hazards
2. Physical Hazards
3. Biological Hazards
4. Psychosocial Hazards

6. CHEMICAL HAZARDS
• A chemical accident is the unintentional release of
one or more hazardous substances which could
harm human health or the environment.
• Chemical hazards are systems
where chemical accidents could
occur under certain
circumstances.

8. CHEMICAL HAZARDS
• Chemicals can affect the skin by contact or
the body either through the digestive system
or through the lungs if air is contaminated
with chemicals, vapours, mist or dust. There
can be an acute (immediate) effect, or a
chronic (medium to long-term) effect from
the accumulation of chemicals or substances
in or on the body.

9. PHYSICAL HAZARDS
• Physical work hazards are workplace
hazards that can affect the body.
• They may include radiation and excessive
noise levels, falls or poorly communicated
excavation routes.
• Examples include:- Unguarded machinery,
exposed moving parts, constant loud noise
hazards, vibrations, working from ladders,
scaffolding or heights

10. PHYSICAL HAZARDS

11. BIOLOGICAL HAZARDS
• BIOLOGICAL HAZARDS, also known as
BIOHAZARDS, refer to biological substances that pose a
threat to the health of living organisms, primarily that of
humans. This can include samples of a microorganism,
virus or toxin that can affect human health.

12. PSYCHOSOCIAL HAZARDS
• A PSYCHOSOCIAL HAZARD is a hazard that
affects the mental well-being or mental health of
the worker by overwhelming individual coping
mechanisms and impacting the worker’s ability to
work in a healthy and safe manner.
• Psychosocial” factors such as stress, hostility,
depression, hopelessness, and job control seem
associated with physical health—particularly heart
disease. Adverse risk profiles in terms of
psychosocial factors seem to cluster with general
social disadvantage.

16. ENVIRONMENTAL DISASTER
• Environmental disasters are defined as man-made
damages to the natural environment that result in
disease and death of living beings; including,
plants, animals and human beings. Environmental
disasters can result from technical accidents,
human, technological or mechanical failure or care
lessness; they can be the consequence of long-term
environmental pollution, such as, the greenhouse
effect or the destruction of the ozone layer.

17. WORST ENVIRONMENTAL
DISASTERS CAUSED BY HUMANS
• On various occasions in history, the planet has been
compelled to shoulder some of the worst environmental
disasters caused by human activities. The disasters range
from wars to nuclear explosions, chemical spill, toxic gas
leaks, and oil spills. Whenever these disasters occur, the
environmental consequences presented are very high and
their impacts are felt for hundreds of years. In some cases,
property and lives remain damaged beyond repair or full
compensation.

18. NUCLEAR DISASTER
• Nuclear disasters result from failures of nuclear plants or
the usage of atomic bombs, whether for testing or attacking.
The worst nuclear disaster ever, was the catastrophe of
Chernobyl (The Chernobyl disaster, also referred to as
the Chernobyl accident, was a catastrophic nuclear
accident). It occurred on 26 April 1986 in the No.4 light
water graphite moderated reactor at the Chernobyl
Nuclear Power Plant near Pripyat, a town in
northern Ukraine which was part of the Soviet
Union (USSR).

20. THE LONDON’S KILLER SMOG
In the heart of industrial revolution, London
was one of the nations influencing the industrialization
market. On this account, there was a lot of energy
utilization, especially the use of coal. This often released
pollutants in the air that made the people used to seeing
Smoggy and heavily polluted air. However, in 1952, this
pollution became disastrous. That winter the weather was
so cold and residents burned more coal than they usually
do to relieve the cold. As a result, the smoke together with
nitrogen oxides, soot, and sulphur dioxide reached high
levels and covered the entire London in Black cloud of
almost complete darkness, a phenomenon that killed over
12,000 people.

22. UNION CARBIDE CYANIDE GAS
LEAK, BHOPAL, INDIA
• In December 3, 1984, a Union Carbide India Limited
pesticide plant in Bhopal, Madhya Pradesh, India,
accidentally released a deadly chemical fog, which killed
more than 10,000 people. They were victims of fatal
poisoning by an isocyanate (pesticide) gas. More than
50,000 people went through treatment due to exposure to
the gas and more than 500,000 people were exposed to the
gas. Proponents claim the gas leak has claimed an
additional 20,000 lives since. It is regarded the worst
industrial chemical disaster ever.

25. BRITISH PETROLEUM OIL SPILL,
GULF OF MEXICO
• In April 20, 2010, there was an explosion and sinking of a of
the deepwater horizon oil rig in the Gulf of Mexico. The oil
rig was leased and controlled by BP (British Petroleum) and
was regarded the most prominent accidental marine oil spill
in the petroleum industry history. Eleven employees died as
a result of the explosion. The explosion also released about
60 million barrels of mixed-grade oil from the disconnected
well, which went on for more than four months. Over
34,000 birds (including egrets and blue heron), hundreds of
sea turtles, about 72 dolphins and other marine vertebrates
and invertebrates were poisoned, suffocated and died in the
floating oil.

27. CHASNALA MINING DISASTER
• Mining disasters can occur either from mining tunnels collapsing,
burying the miners working underneath the earth, or by the
spillage of hazardous chemicals employed for dissolving the
minerals to be extracted. An example is in the mining of gold,
during which cyanide is used, and often carelessly spilled on
farming land. The collapse of architecture, buildings, bridges, or
dams can also be followed by destructive consequences; e.g., the
breaking of dams can release enormous amounts of water
resulting in devastating flooding, or spillage of chemicals.
(The Chasnala mining disaster was a disaster that happened on
27 December 1975 in a coal mine in Chasnala near Dhanbad in
the state of Jharkhand, INDIA. An explosion in the mine
followed by flooding killed 372 miners).

29. ACCIDENTAL & FIRE DISASTERS
• Accidents in transportation, whether by airplane,
ship, train or motorized vehicle can have disastrous
effects, e.g., by the involvement of large numbers
of passengers, by spilling huge amounts of oil or
chemicals, or by causing fire, collapse of buildings
or blockage of passage ways.
• Forest fires in arid areas can also be caused by
human carelessness of e.g., by leaving behind
pieces of broken glass – enough to incite a fire.