proposed integrated complex for delhi judicial academy

Rapid Environmental Impact Assessment (REIA) Study for Proposed Integrated Complex for Delhi Judicial Academy,
National Law School, and National Institute for Mediation & Conciliation at Dwarka, New Delhi
Figure 5.1: Noise level due to operation of various construction equipments
It is a known fact that there is a reduction in noise level as the sound wave passes through a barrier.
The transmission loss values for common construction materials are given in Table 5.2.
Table 5.2
Transmission loss for common construction materials
MATERIAL
THICKNESS OF
CONSTRUCTION
DECREASE IN NOISE
LEVEL DB(A)
MATERIAL (INCHES)
Light concrete
4 38
6 39
Dense concrete 4 40
Concrete block
4 32
6 36
Brick 4 33
Granite 4 40
Thus, the walls of the adjoining buildings along with other factors like air absorption, vegetal cover
etc. would result in significant attenuation of atleast 20 - 25 dB(A) at 100 m distance. The resultant
noise levels on proposed project site at 50m distance at peak level of construction are anticipated to
be about 55 – 60 dB(A), which is well within the limit for commercial area during the day time.
Further to minimize these potential impacts, major construction activities would be scheduled
during normal daylight working hours and would be implemented consistent with the applicable
standards. The construction contractor will use equipments that are adapted to operate with
appropriate noise muffling devices resulting in the least possible noise. Every effort would be taken
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