How much is the noise level (in dBs) of 'Zones of concentrated average noise sources' as per IS: 4594-1968, based on noise point of view?

Question

Question

This question was previously asked in

BHEL Engineer Trainee Civil 24 Aug 2023 Official Paper

Answer 1

Concept:

Zone	Noise Level
a) Quiet	≤ 60 dBs
b) Zones of concentrated noise sources quite at times	60–70 dBs
c) Zones of concentrated average noise sources	70–80 dBs
d) Zones of high noise sources	80–90 dBs
e) Zones of extremely high noise sources	> 90 dBs

Additional Information

The acceptable noise levels for indoor levels in different types of residential areas is given in below table:

Acceptable Indoor noise levels for various types of buildings
S.No.	Location	Noise level dB
1	Radio & TV studio	25-30
2	Music room	30-35
3	Hospitals, classrooms, auditoria	35-40
4	Apartments, hotels, homes	35-40
4	Conference, rooms, small offices	35-40
5	Courtrooms, private offices, libraries	40-45
6	Large public offices, banks, stores, etc	45-50
7	Restaurants	50-55

IS:4954-1968:- Recommendations for Noise Abatement in Town Planning

The acceptable noise levels for outdoor and indoor levels in different types of residential areas is given in below table:

Acceptable outdoor noise levels in residential areas
S.No.	Location	Noise level dB
1	Rural	25-35
2	Suburban	30-40
3	Residential (Urban)	35-45
4	Urban (residential and business)	40-50
5	City	45-55
6	Industrial area	50-60