Question

Daytime sound level in the silent zone is
(a) 20 dB
(b) 40 dB
(c) 50 dB
(d) 70 dB

Answer 1

The half-century number denotes the daytime sound level in the silent region. This decibel is equivalent to a suburb conversation that takes place at home. Silent areas span 100 meters around hospitals, schools, etc. Noise over 70 dB can start to damage your hearing over a sustained period of time. A whisper is 20 to 30 dB.

Complete step by step answer:
Noise is referred to as the unwanted and disturbing sound which causes noise pollution. Noise is measured in decibels (dB) , showing the loudness of the noise. The level of noise refers to the noise decibel levels created by any device or machine.
- There are four classified areas, which are manufacturing, commercial, residential, and silent areas based on noise level and air quality requirements.
- The silent zone, also known as the skip zone, is the area where radio transmission can not be received within 100 meters of educational institutions, hospitals, etc. In the silent zone, the sound level in the daytime is around 50 dB.
The permissible maximum sound level limit for the silent zone is 50 decibels during the daytime. The acceptable limit for night hours is 40 decibels.
So, the correct answer is, ‘50 dB’.

Note: The allowable noise level in India has been set by the CPCB for various areas. The acceptable maximum in industrial areas is 75 dB during the daytime and 70 dB at night. It is 65 dB and 55 dB in commercial areas, while it is 55 dB and 45 dB in residential areas during daytime and night time, respectively. The maximum allowable diesel generator noise level for new generators with a rated capacity of up to 1000 kilo- volt amps (KVA) is 75 dB, according to CPCB guidelines. In addition, for a diesel generator, there should be an acoustic enclosure. In handling the room acoustically, the generator noise reduction enclosure helps. To ensure that the neighbors are undisturbed, the enclosure is constructed of generator soundproof materials that minimize noise emissions.