OHS Code Explanation Guide

Published Date: July 01, 2009
Bookmark this page

Part 16 Noise

Section 216 Duty to reduce

The employer is required to reduce worker exposure to noise in areas where workers may be present. Noise is a recognized workplace hazard. It must be assessed as required by section 7 of the OHS Code, and then eliminated and controlled as required by section 9.

The term “reasonably practicable” is not intended to provide an opportunity or an excuse for not meeting the requirements of this Part. Use of the term indicates the preferred action that should be taken and is usually associated with the minimum requirements that should be met.

As required by section 9, noise must be controlled through the use of engineering controls first, then administrative controls if engineering controls are not effective. Only if engineering or administrative controls do not or are impracticable to eliminate or reduce a hazard sufficiently is an employer permitted to use appropriate personal protective equipment.

Engineering controls

Four main types of engineering controls can be used to reduce or eliminate noise:

(1) substitution – replace noisy equipment, machinery or processes with quieter ones;

(2) modification – modify the way equipment operates so that it generates less noise. This may include installing a muffler, reducing equipment vibration by dampening or bracing, improved lubrication, balancing rotating parts or operating equipment at a lower speed. Alternatively, the area itself can be modified. Reverberation, for example, can be reduced by covering walls with sound absorbing materials;

(3) isolation – this may involve isolating workers from a noisy area by having them work in an enclosed room. Examples of this approach include:

(a) segregating noisy areas with sound barriers and partitions;
(b)isolating noisy equipment by placing it in an enclosure; and
(c) using sound absorbent material and covers over noisy equipment; and

(4) maintenance – malfunctioning or poorly maintained equipment generates more noise than properly maintained equipment. Noise control equipment must also be properly maintained to be effective.

Developing engineering controls may involve engineers, safety and industrial hygiene personnel and the workers who operate, service and maintain the equipment. The effectiveness of the controls will depend on a thorough assessment of the noise source and individual worker exposure. The contribution of each noise source to the overall noise level must be considered.

The control options available should be evaluated based on their effectiveness, cost, technical feasibility and implications for equipment use, service and maintenance. Enclosing a piece of equipment, for example, may cause it to overheat or create maintenance difficulties. Other potential complications such as effects on lighting, heat production, ventilation and ergonomics, should also be considered. The function and purpose of planned or existing controls must be fully discussed with workers so they understand the purpose of the controls and do not inadvertently interfere with them.

Administrative controls

Administrative controls involve changes in work schedules or operations that reduce worker noise exposure. Typical controls include rotating work schedules or changing production schedules to limit the amount of time workers are exposed to noise.

Protective equipment

When engineering and administrative controls cannot reduce noise exposure sufficiently, or where they are not reasonably practicable, the employer must provide workers with hearing protection (see section 222). Hearing protection is considered to be any device designed to reduce the level of sound reaching the eardrum. Earmuffs and earplugs are the main types of hearing protection typically used. A wide range of hearing protection can be found within each of these categories. The amount of protection or sound attenuation provided by a hearing protector depends on its characteristics and how it is worn. The selected hearing protector must be capable of keeping noise exposure at the ear below the occupational exposure limit for noise.