Page 147 - IGC BOOK

Exposure limit values and action values

Lower exposure action values

• a daily or weekly personal noise exposure of 80 dB (A-weighted).
• a peak sound pressure of 135 dB (C-weighted).
Upper exposure action values

• a daily or weekly personal noise exposure of 85 dB (A-weighted).
• a peak sound pressure of 137 dB (C-weighted).

Exposure limit values

• a daily or weekly personal noise exposure of 87 dB (A-weighted).
• a peak sound pressure of 140 dB (C-weighted).
If the worker is found to have exposed to these values, then the employer must take actions to
reduce exposure.

Where the exposure of an employee to noise varies markedly from day to day, an employer may
use weekly personal noise exposure in place of daily personal noise exposure for the purpose of
compliance with these regulations.

Basic Noise Control Measures

Noise can be controlled by the following ways:
• Source Eliminating or reducing noise at the source.
• Path - Barriers to transmit noise through air.
• Receiver – protecting the receiver.

Eliminating or Reducing Noise at Source

Implement low noise purchasing policy for machinery and equipment and replace the machinery
that causes noise with less noisy machinery.

Eliminate – removing noise from the source is not practically possible in many cases.

Substitute – change the noise source using alternate methods or machine (e.g. diesel operated
forklift replaced with battery operated to reduce noise.)

Modifying the process – changing the work processes can reduce noise level. E.g. replacing
pneumatic screw guns with manual process. Other methods can be replacing gear drives with
belt drives.

Maintenance - periodic maintenance and repair, such as repair of faulty bearings, broken gear
teeth, blunt cutting tools, and maintenance of belts and fans and other moving parts.

ENSIGN | Unit IG2 – Element 5 – Physical and Psychological 7
Health