Page 124 - GRIHA Manual Volume V - Introduction to National Rating System

Evaluation procedure 117

CRIteRIon 29

ACCeptAble outdooR And

IndooR noIse levels

GRIHA-speciic information (Commitments, compliances,

appraisal)

Objective
to use appropriate noise controls for providing acceptable levels of outdoor and indoor noise
levels to enhance comfort.

29. 1 Commitment
29.1.1 ensure that the outdoor noise level conforms to the CPCb-environmental Standards-
noise (ambient standards) as given in table 29.1.

Table 29.1 Noise (ambient standards)
Area code Area category Limit in dB (A) Leq (equivalent sound level)
Day time Night time
A Industrial area 75 70
B Commercial area 65 55
C Residential area 55 45
D Silence zone 50 40

notes:
# daytime is reckoned between 6 a.m. and 9 p.m.
# nighttime is reckoned between 9 p.m. and 6 a.m.
# Silence zone is defined as areas up to 100 m around premises such as hospitals, educational institutions, and
courts. the silence zones are declared by competent authority.
# mixed categories of areas should be declared as one of the four above mentioned categories by the
competent authority and the corresponding standards shall apply.

29.1.2 ensure that the indoor noise levels conform to the levels described in nbC 2005 (biS
2005a) as given in table 29.2