Question

The permitted noise level in industrial zone is
A. 75 dB
B. 65 dB
C. 55 dB
D. 100 dB

Answer 1

The introduction of unwanted and harmful elements into the atmosphere that brings about undesired changes is known as pollution. It becomes very dangerous to the living organisms if the rate of pollution causing materials exceeds a harmful extent.

Complete answer:
Noise is the accumulation of unwanted sound that is not within normal hearing limits. The accumulation of noise in the environment due to several activities such as transportation, industrial, and other types of recreational activities are known as noise pollution. It is the propagation of noise on the various activities of humans as well as the animals and is harmful to them.
The noise that is produced through the agency of several types of industrial machines particularly heavy machines, firms and factories are termed as industrial noise pollution. It is the sound energy that is released by the working of the industries. Industries such as mining and steel, welding, construction, ship building and road and rail work are known to generate a considerable amount of unwanted noise and cause noise pollution.
Noise pollution is measured in decibels and is used to express the relative intensity of sound in the scale of 0 to 130. The sound is also limited in various ways according to the recommendation of WHO. The industrial sound or noise exposure limit that is permitted is 75 dB. This amount is allowed during the daytime.
The permitted sound level for the commercial area is about 65 dB while for the residential areas it is about 55 dB. The noise level above 80 dB is considered as noise pollution and so, the level of 100 dB is considered as noise pollution and is not permitted. It can contribute to several types of health hazards.

Therefore, the correct option is option A.

Note: It affects the humans to a great extent and it causes an increased rate of coronary artery diseases. Noise pollution can have an undue effect on humans as well as animal life and it is found to increase the rate of death by interfering with various functions related to sound, reproduction and navigation. In the industrial zones, the permitted noise levels are 75 dB. Any increase above this level is considered as noise pollution and is not allowed.