I. National ambient air quality standards
Gazette Notification No. SO 384(E) Air (PCP) dt. 11.04.94, EPA-GSR 176(E) 02.04.96, S.O. 955 (E) Air (PCP) 14.10.98
Pollutants |
Time Weighted Average |
Industrial |
Resident,Rural & Other area |
Sensitive Area |
SO 2 |
Annual* |
80 m g/m 3 |
60 m g/m 3 |
15 m g/m 3 |
24 hours** |
120 m g/m 3 |
80 m g/m 3 |
30 m g/m 3 |
NO x |
Annual* |
80 m g/m 3 |
60 m g/m 3 |
15 m g/m 3 |
24 hours** |
120 m g/m 3 |
80 m g/m 3 |
30 m g/m 3 |
SPM |
Annual* |
360 m g/m 3 |
140 m g/m 3 |
70 m g/m 3 |
24 hours** |
500 m g/m 3 |
200 m g/m 3 |
100 m g/m 3 |
RPM |
Annual* |
120 m g/m 3 |
60 m g/m 3 |
50 m g/m 3 |
24 hours** |
150 m g/m 3 |
100 m g/m 3 |
75 m g/m 3 |
Lead (Pb) |
Annual* |
1.0 m g/m 3 |
0.75 m g/m 3 |
0.50 m g/m 3 |
24 hours** |
1.5 m g/m 3 |
1.00 m g/m 3 |
0.75 m g/m 3 |
NH 3 |
Annual* |
0.1 mg/m 3 |
0.1 mg/m 3 |
0.1 mg/m 3 |
24 hours** |
0.4 mg/m 3 |
0.4 mg/m 3 |
0.4 mg/m 3 |
CO |
Annual* |
5.0 mg/m 3 |
2.0 mg/m 3 |
1.0 mg/m 3 |
24 hours** |
10.0 mg/m 3 |
4.0 mg/m 3 |
2.0 mg/m 3 |
* Annual arithmetic mean of minimum 104 measurements in a year taken twice a week 24 hours at uniform interval.
** 24 hours/8 hourly values should be met 98% of the time in a year. However, 2% of the time, it may exceed but not on two consecutive days.
NOTE
• National Ambient Air Quality Standard : The levels of air quality with an adequate margin of safety, to protect the public health, vegetation and property.
• Whenever and wherever two consecutive values exceeds the limit specified above for the respective category, it would be considered adequate reason to institute regular/ continuous monitoring and further investigations.
• The State Government/ State Board shall notify the sensitive and other areas in the state within a period of six months from the date of Notification of National Ambient Air Quality Standards.
II. Noise : ambient air quality standards
EPA- GSR-1063 (E), dt. 26.12.89
Area code |
Category of area |
Unit in dB(A) L eq |
Day time |
Night time |
A |
Industrial area |
75 |
70 |
B |
Commercial area |
65 |
55 |
C |
Residential area |
55 |
45 |
D |
Silence Zone |
50 |
40 |
Note:
• Day time is reckoned in between 6 a.m. and 10 p.m.
• Night time is reckoned in between 10.00 p.m. and 6.00 a.m.
• Silence zone is defined as areas upto 100 meters around such premises as hospitals, educational institutions and courts. The silence zones are to be declared by the competent authority.
• Mixed categories of areas should be declared as “one of the four” above-mentioned categories, by the competent authority and the corresponding standard shall apply. |
