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PRESSURES
ON TRANSPORT
Such an increase in the number of vehicles on the road has caused tremendous
pollution of air. This, in turn, has affected health of the people.
It can very easily be said that most urban pollution issues relate to
the vehicular pollution.
The unprecedented spurt in the number of vehicles on our roads has thoroughly
polluted our atmosphere. In fact, studies carried out by several different
agencies have clearly indicated that the most significant contributor
to the poison in urban air, has been the vehicular pollution. While industrial
air
POINTS
TO PONDER Size
of a vehicle and the amount of pollution it causes are related. Thus
bus may be more polluting. However, as the number of passengers it
carries is several times more than what a car and a scooter carries,
it is clear that the per capita pollution caused by a bus is much
less than that caused by a car or a scooter.
Trains
are least polluting considering the number of passengers they carry
at any given time.
Cutting
down on the need to travel by a vehicle has to be seriously thought
of, Neighbourhood schools and offices will largely bring down the
load on our roads in terms of moving vehicles. Consequently it will
render our air that wee bit cleaner.
Two-stroke
and four-stroke engines are more polluting. They are less fuel efficient.
It is high time their engines are redesigned.
The
seven-seater auto is much more polluting than the three-seater. Two
seven-seater autos occupy the same space as a bus. However, while
the bus accommodates approximately 50 passengers, a seven seater can
take in only so many - seven.
There
is a gas pipeline proposed between Vijaywada and Hyderabad. A fuel
pipeline, on similar lines, would go a long way in solving our air
pollution related problems. A lot many gases escape into the air when
the fuel is being transported and distributed. A common fuel pipeline
should definitely be given a thought.
Transport
of building material both live and dead (meaning fresh, unused and
used building material respectively), causes a lot of pollution in
terms of creating dust and particulate matter. The fallen material
on the road too might get crushed and further create suspended particulate
matter in the air. pollution is localised in nature, moving vehicles
which pump gases into the air every minute, bring entire cities into
the grip of air pollution.
Sulphur dioxide, nitrogen oxides, suspended particulate matter, carbon
monoxide, benzene, lead and other toxins gush into the air through emissions
from our vehicles. These pound our bodies every minute and are debilitating
us through known and unknown ways. The situation is indeed alarming.
Various factors are responsible for the situation: growing population,
heavy dependence on private vehicles, failure of public transport system
to meet the growing demands, low fuel efficiency, bad condition of roads,
heavy movement of traffic are only a few of them.
A curious fact is that growth in the number of vehicles has correspondingly
increased the time people spend reaching their destination. Despite having
their own vehicles, people are having to spend more time on the roads.
This is because the growing number of vehicles on the road has considerable
slowed down the movement of traffic itself. This has also resulted in
more gases being pumped into the air.
Studies done in Hyderabad show that between 1993-1996, the pollution level
in the city has gone up by 170 tonnes, largely because of a growth in
vehicles. Vehicles contribute more than 600 tonnes of pollutants everyday.
HOW
SAFE IS UNLEADED FUEL?
Unleaded fuel is manufactured by using aromatics instead of the tetra
ethyl lead (TEL) aromatics consist mainly of benzene, toluene, xylenes
and ethyl benzene. Benzene, a volatile and highly toxic substance, is
emitted into the atmosphere by evaporation through the vents of the fuel
tank in cars, the carburettor and intake system, and also through the
exhaust.
Benzene makes its way into gasoline either through the aromatic reformate
added to increase the octane number instead of TEL, or during secondary
manufacturing processes like FCC and delayed coking.
A sample of leaded petrol with an octane rating of 98 RON (Researce octane
Number), for example, would have an aromatic content of 29 percent of
volume (V%). But in unleaded petrol, this has to be increased to around
43 percent to obtain 98 RON. The high aromatic content of unleaded fuel
also results in greater emission of carcinogenic polyaromatic hydrocarbons
(PAH).
Source
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