of Noise Pollution
Noise generation is associated with
most of our daily activities. A healthy human ear responds to a very wide range
of SPL from - the threshold of hearing at zero dB, uncomfortable at 100-120 dB
and painful at 130-140 dB(3). Due to the various adverse impacts of noise on
humans and environment (See LO-5), noise should be controlled. The technique or
the combination of techniques to be employed for noise control depend upon the
extent of the noise reduction required, nature of the equipment used and the
economy aspects of the available techniques.
The various steps involved in the
noise management strategy is illustrated at Fig 4. Reduction in the noise
exposure time or isolation of species from the sources form part of the noise
control techniques besides providing personal ear protection, engineered
control for noise reduction at source and/or diversion in the trajectory of
Control at Source
The noise pollution can be
controlled at the source of generation itself by employing techniques like
the noise levels from domestic sectors: The domestic noise coming from radio, tape recorders, television sets, mixers, washing machines,
cooking operations can be minimised by their selective and judicious operation.
By usage of carpets or any absorbing material, the noise generated from felling
of items in house can be minimised.
Maintenance of automobiles: Regular servicing and tuning of
vehicles will reduce the noise
levels. Fixing of silencers to automobiles, two wheelers etc., will reduce the
Control over vibrations: The vibrations of materials may be controlled using proper foundations, rubber padding etc. to
reduce the noise levels caused by vibrations.
Low voice speaking: Speaking at low voices enough for communication reduces the excess noise levels.
on usage of loud speakers: By
not permitting the usage of loudspeakers in
the habitant zones except for important meetings / functions. Now-a-days,
the urban Administration of the metro cities in India, is becoming stringent on
usage of loudspeakers.
of machinery: Optimum
selection of machinery tools or equipment reduces excess noise levels. For example selection of chairs, or selection
of certain machinery/equipment which generate less noise (Sound) due to its
superior technology etc. is also an important factor in noise minimisation
of machines: Proper
lubrication and maintenance of machines, vehicles etc. will reduce noise levels. For example, it is a common
experience that, many parts of a vehicle will become loose while on a rugged
path of journey. If these loose parts are not properly fitted, they will
generate noise and cause annoyance to the driver/passenger.
Similarly is the case of machines.
Proper handling and regular maintenance is essential not only for noise control
but also to improve the life of machine.