Question

The permissible noise level in industrial areas in India is

• A. 65 dB for day time and 55 dB at night
• B. 75 dB for daytime and 70 dB at night
• C. 55 dB for daytime and 45 dB at night
• D. 45 dB for daytime and 35 dB at night

Hint:

• Indian Noise Pollution (Regulation and Control) Rules, 2000, define ambient noise standards.
• Standards vary by area type (Industrial, Commercial, Residential, Silence Zone) and time (Day/Night).
• For Industrial Areas:
  • Day Time: 75 dB(A) Leq
  • Night Time: 70 dB(A) Leq
• For Commercial Areas: Day 65 dB(A), Night 55 dB(A).
• For Residential Areas: Day 55 dB(A), Night 45 dB(A).
• For Silence Zones: Day 50 dB(A), Night 40 dB(A).

Answer 1

The Correct Option is B

In India, the noise pollution standards are prescribed by the Central Pollution Control Board (CPCB) under the Noise Pollution (Regulation and Control) Rules, 2000. These rules specify ambient noise quality standards for different area categories: Industrial, Commercial, Residential, and Silence Zones, with different limits for daytime and nighttime. The ambient air quality standards in respect of noise for Industrial areas are:

• Day Time (6:00 a.m. to 10:00 p.m.): 75 dB(A) Leq
• Night Time (10:00 p.m. to 6:00 a.m.): 70 dB(A) Leq

(Note: Leq refers to the equivalent continuous sound level, and dB(A) indicates A-weighted decibels, which mimics human hearing response). Let's check the options against these standards: Option (a) 65 dB (day) and 55 dB (night): These are the limits for Commercial areas. Option (b) 75 dB (day) and 70 dB (night): These match the limits for Industrial areas. Option (c) 55 dB (day) and 45 dB (night): These are the limits for Residential areas. Option (d) 45 dB (day) and 35 dB (night): These are lower than the Silence Zone limits (Silence Zone: 50 dB day, 40 dB night). Therefore, the correct permissible noise level for industrial areas in India is 75 dB for daytime and 70 dB at night. \[ \boxed{\text{75 dB for daytime and 70 dB at night}} \]