Noise and Vibration
Quick Links: Noise Risks, Control of Noise, Vibration,
Noise - a checklist and Think
About.
Noise Risks
Exposure to excessive noise accelerates the normal hearing loss
that occurs with age. It is also associated with the onset of
tinnitus (continuous ringing in the ears), interference with
workers' communication and concentration, and causes additional
stress and fatigue. Instantaneous damage can result from exposure
to extremely loud noise but most damage is cumulative, making it
more difficult to notice until it is too late. The health effect of
noise exposure depends primarily upon the noise level (measured in
decibels or dB(A)) and the duration of exposure.
Typical levels
Typical levels of noise
| decibels |
Types of Noise |
| 0 |
Hearing threshold |
| 60 |
Normal conversation |
| 90 |
Typical process plant |
| 100 |
Pneumatic drill/chain saws |
| 120 |
Diesel engine room/riveting |
| 140 |
Jet engine taking off (25m away) |
Control of Noise
The Noise at Work Regulations 1989 apply to all work places and
require employers to reduce the risk of hearing damage to the
lowest level reasonably practicable. Options for reducing exposure
to noise are described below in order of preference.
It is always best to control noise at source; the wearing of
ear defenders is a last resort only.
- Reduce noise levels by design by changing operating procedures
and processes, and buying low noise equipment (manufacturers and
suppliers of high noise equipment are obliged to provide adequate
information about their products).
- Implement methods of noise control such as silencers.
- Reduce the duration of employees' exposure to noise and provide
hearing protection devices.
Where employees' daily exposure to noise levels is likely to
be at or around 85 dB(A) the Regulations require employers
to:
- Assess noise exposure and keep a record of the assessment.
- Provide information and training on the risks of exposure to
noise and action to minimise the risks for employees.
- Make suitable ear protectors available to employees.
- Maintain and repair protective devices.
If workers need to raise their voices to speak to each other
at a distance of two metres apart it is likely that some action is
required. A competent person must carry out noise assessments. The
competence of the person will depend on the complexity of the
situation. You may wish to have a staff member trained to carry out
the assessment or employ a consultant. The assessments must be
reviewed when there has been a significant change in the workplace
or if you think there is some other reason to suspect it is no
longer valid e.g. staff begin to complain about the noise levels
again. Daily noise exposure of employees depends on the level of
noise and the length of time they are exposed to it.
Where daily noise exposure levels are at or above 90 dB(A) the
Regulations place additional duties on employers. They must ensure
that exposure to noise is reduced to the lowest level reasonably
possible other than by the use of ear protectors.
They must also mark ear protection zones where noise levels
are high and ensure ear protectors are provided and worn by all
exposed workers.
Vibration
Vibration is often associated with noise but may be a problem in
its own right. Resulting health effects from exposure to vibration
can include headaches, sickness, spinal disorders and varicose
veins where the vibration is acting on the whole body, and areas of
bone decalcification, tissue hardening, osteoarthritis and
vibration induced white finger where it is acting on the hand and
arm only.
Vibration can be a particular problem in jobs such as drivers
of heavy vehicles and operators of heavy machinery, road drillers,
chain saw and pneumatic tool operators. Appropriate control
measures will vary but may include design considerations for
vehicles and equipment, control of exposure times, proper
maintenance, protective clothing and alterations to working
practices.
Noise - a checklist
- Has the risk of hearing damage been reduced as far as
reasonably practicable?
- Has the noise exposure been properly assessed where
necessary?
- Have staff been provided with adequate information and
training?
- Is ear protection provided where necessary?
Think about.....
- Is plant and machinery chosen with noise reduction in
mind?
- Can plant and machinery be fitted with noise reduction
devices?
- Can noisy areas be enclosed?
- Has the number of people working in noisy areas been reduced as
far as possible?
- Has the length of time spent in noisy areas minimised?
- Are ear protection zones used where appropriate?
- Are noise reduction techniques used in preference to ear
protection devices?
- Has the noise exposure been assessed by a competent
person?
- Has the assessment been recorded?
- Is the assessment repeated when changes in plant or procedures
make it unreliable?
- Have the risks of noise exposure been properly explained to all
exposed staff?
- Have staff been trained in the use of appropriate control
measures?
- Is adequate induction and refresher training provided?
- Has protection suitable for noise been selected?
- Has protection suitable for the staff who are to wear it been
selected?
- Is ear protection properly worn and supervised?
- Is ear protection properly stored, maintained and
repaired?
- Are spare protective devices available for use at short notice
where necessary?