Vibration

• Author: International Labour Organization
• Pages: 115-117

Meetings-MESHA-Final Code-2010-10-0355-1-En.doc/v2 115

13. Vibration

13.1. Introduction

13.1.1. Vibration in the workplace is generally classified as:

(a) whole body vibration, which is transmitted by sitting or standing on vibrating

surfaces, such as when driving tractors and other farm machinery. Prolonged

exposure can lead to severe back pain and other musculoskeletal disorders; and

(b) hand–arm vibration, which is transmitted through the use of hand-held powered

equipment like chainsaws, brush cutters and hedge trimmers. Prolonged exposure can

lead to damage to the hand and arm muscles (hand–arm vibration syndrome), joints

and nerves.

13.1.2. Short duration exposure to whole body vibration or to hand–arm vibration

may result in temporary disability, but prolonged or repeated exposure leads to permanent

damage. The main concerns are therefore the magnitude of vibration transmitted and the

duration of exposure. Exposure to whole body vibration is unlikely on its own to cause

injuries, but it can aggravate existing back injuries which may cause pain.

13.1.3. As with noise, vibration is best reduced or eliminated at source through

good design of equipment. For example, tractors with in-built suspended cabs or chainsaws

with anti-vibration mountings can reduce vibration emission levels significantly.

Engineering controls to reduce vibration subsequently may be possible but these are

usually less effective. PPE, such as anti-vibration gloves, is not a substitute for engineering

controls and should only be considered as a last resort. However, exposure levels will be

reduced by spending less time working with vibrating equipment.

13.2. Hazard description

13.2.1. Common sources of whole body vibration include driving or standing on a

tractor, all-terrain vehicles or other machinery to perform tasks like baling, drilling,

foraging, spraying, ploughing and harrowing. The effects of whole body vibration are

made worse by driving over rough ground or over bumps or potholes. It is also

experienced when standing on vibrating platforms, such as mechanical harvesters and

motorized tree fruit picking platforms, or working near large machinery, such as milling or

threshing machines.

13.2.2. Common sources of hand–arm vibration in agriculture are the use of hand-

held vibratory tools and equipment, such as chainsaws, brush cutters or grinders. Other

sources include impact wrenches used in equipment maintenance and repair, chainsaws,

brush saws and weed saws, portable fruit, nut or kapok harvesters and vibro-compactors.

13.3. Risk assessment

13.3.1. Employers should assess the risks to their workers from both whole body

vibration and hand–arm vibration, and in particular:

(a) identify the sources of vibration and the tasks that give rise to exposure, considering

the types of equipment being used, the conditions under which they are used and the

duration of exposure;