Version NGNO001
Noise Guidance
INTRODUCTION
Noise is defined as "unwanted sound" and in the workplace, is produced by a wide variety of activities, plant,
machinery and equipment. In situations where this exceeds 80db(A), it is necessary to make assessments of
employees daily exposure levels. Where these exceed the ''action levels'' contained within current regulations,
action to control exposure to noise must be taken. This document is intended to provide guidance on preventing
hearing damage and complying with legal requirements.
MAIN HAZARDS
Hearing Damage
Levels of noise in excess of 80dB(A) can cause irreversible hearing damage. When people are exposed to high
noise levels for even short periods, they may experience temporary hearing loss, but after returning to a normal
environment, this soon recovers. However, when employees are exposed to high noise levels every working day
for many years, they slowly develop a permanent hearing loss. It is a cumulative process that worsens with time
and its affects may not be appreciated until years later. The risks become greater with both increases in sound
level and the time spent in a noisy environment. Some very high levels of impulsive noise, lasting only a fraction
of a second, can cause instantaneous damage.
OTHER EFFECTS OF NOISE
High levels of noise can also have other effects on employees and has been shown to increase stress, blood
pressure and tiredness. It can also cause other psychological effects, interfere with communication and reduce
the efficiency of those exposed.
CONTROL MEASURES
Precautions
Employers must identify noisy areas, take measurements, make assessments and then carry out a programme of
work that will depend on the level of exposure, or ''action level'' to reduce noise exposure.
Action Levels
Current regulations require employers to identify noisy activities and areas where employees are likely to be
exposed to levels of noise above 80 dB(A). Three action levels are specified:

the First Action Level - a daily personal noise exposure of 80 dB(A) to 85 dB(A)

the Second Action Level - a daily personal noise exposure of 85 dB(A) or more

the Peak Action Level - a peak sound pressure of 180 pascals or more.

Employers must also keep records of assessments, provide ear protection, where required, identify hearing
protection zones, and reduce noise at source where the second action level is exceeded.
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Noise Guidance
ASSESSMENT OF EXPOSURE
As a rough guide, any area where it is difficult to hold a conversation without raising voices, or where it is
necessary to shout to someone at a distance of about 2 metres, should be investigated more thoroughly.
Where a potential problem has been identified, measurements of noise using a suitable, properly calibrated,
sound level meter must be made to accurately determine the problem that exists.
Assessments of "peak" pressure are most likely to be needed where workers are exposed to loud noises from
exploding sources (e.g. cartridge tools). Care must be taken when measuring peak levels because many sound
level meters are not capable of measuring this value. Meters with only a "Fast" or "Impulse" capability do not have
a quick enough response to accommodate measurements of "peak" levels.
Making the Assessment
The purpose of the assessment is to:

identify all workers likely to be exposed.

provide enough information to enable appropriate action to be taken.
The person undertaking the assessment must be competent.
Review of Assessments
Assessments will have to be reviewed whenever changes occur. These may include:

the installation of new machinery.

substantial changes in workload, work pattern, or machine speeds.

changes in building structure or machine layout.

machine wear or general deterioration.

modifications to machinery.

Complaints from employees.

Potential hearing loss compensation claims
Although there may not have been any obvious changes, workplaces should be checked at least every two years.
Levels can creep upwards without being noticed e.g. as the result of machine wear.
Records of Assessments
Suitable records of assessments should be kept. These will include details of the workplaces, areas or jobs
assessed and what the results were and when the assessments were made.
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Noise Guidance
In addition it is advisable to:

tabulate records of the noise exposure resulting from various tasks and activities, identified by person,
work, area or operation.

include a plan showing noise levels at various places in the premises.

record who works in various locations and typical working times.

record the type of workplace likely to be visited by employees who move about and the associated noise
levels and exposures.

ACTION REQUIRED IF EXPOSURE EXCEEDS THE FIRST ACTION LEVEL OF 80 DB(A)
Exposure Level between 80-85 dB(A)
It is not compulsory to wear ear protection when exposure is between the first and second action levels but is
compulsory to:

provide and maintain ear protection for all those who request it.

provide all employees with sufficient information, instruction and training on the level of exposure they
are subjected to. This should include the risk of damage to the employee's hearing that such exposure
may cause, the steps the employee should take to minimise the risk and the steps that must be taken in
order to obtain the personal ear protection provided.
Exposure Level above 85dB(A) or a Peak of 180 pascals
Ear protection is compulsory when the exposure exceeds the second action level of 85 dB(A) or the peak action
level of 180pascals. In addition, it is also necessary for the employer to:

ensure that ear protection is not only provided but will also achieve sufficient attenuation to keep the risk
of hearing damage to one that would be below the second or peak action levels, as the case may be.

identify and mark areas designated as ear protection zones using appropriate safety signs.

provide all employees with sufficient information, instruction and training.

ensure that all employees entering ear protection zones use the personal ear protection provided and
report any defects in this equipment.

reduce noise levels, so far as reasonably practicable, by other means than providing hearing protection
e.g. engineering controls, acoustic enclosures.
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Noise Guidance
HIERARCHY OF EFFECTIVE NOISE CONTROL
Where noise levels have the potential to cause injury, reasonable steps should be taken to reduce the noise to
the lowest practical level. The following measures form the hierarchy of noise control:

reducing noise emission at source, i.e. by design.

isolating the noise source.

ear protection, e.g. ear muffs, ear plugs.

reducing the duration of exposure, i.e. by offering rest breaks in a quiet area away from the noise.
EAR PROTECTION
Choosing a Suitable Type of Protector
Any hearing protection issued should be adequate enough to provide sufficient attenuation to maintain values
below the second and peak action levels. It should be of a suitable fit and be compatible with any other protective
equipment or special clothing that is worn.
Individuals differ in what they find comfortable and should preferably be given a choice.
Equipment provided should remain personal and not be passed from one person to another. For hygiene reasons,
ear plugs should not be issued to persons who are subject to ear infections.
Ear Protection Zones
Areas where the second or peak action levels are exceeded must be designated hearing protection zones. These
zones should be clearly demarcated and the entrances to the zone marked with appropriate safety signs i.e. blue
circular mandatory signs with relevant pictogram.
No employee should be permitted to enter a hearing protection zone without wearing hearing protection. Where it
is not practical to mark hearing protection zones, for example, where noise sources are portable and are moved
to different locations, it would be necessary to make alternative arrangements. This could include attaching signs
to tools, warning that protectors must be worn when used, or by giving written instructions designating particular
tasks or operations as ones where protectors must be used.
MAINTENANCE OF EQUIPMENT
All equipment used for noise protection should be maintained.
Ear Muffs
These should be maintained in a clean, serviceable condition and kept in a clean locker or cupboard when not in
use. They should be regularly examined for damage.
Ear Plugs
Where disposable protectors are used, dispensers should be topped up regularly to ensure that supplies are
continuously available. Re-useable plugs should be kept in a clean storage place when not in use.
Noise Control Equipment
Silencers or noise enclosures that are provided as control measures must be maintained in a good condition.
Spot checks should be made to monitor their effectiveness.
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Noise Guidance
NEW MACHINERY
Designers, manufacturers, importers and suppliers of plant and machinery for use at work have a legal obligation
to provide articles that are safe and without risks to health and to provide information needed for their safe use,
including information on noise emission.
Information should therefore be obtained on noise emitted by machinery, plant or equipment, prior to its purchase.
These duties also mean that if a machine is likely to produce noise capable of harming health, action will need to
be taken to:
a.
Reduce the noise to the extent reasonably practicable. This will involve an engineering appraisal of the
feasibility of noise control and the application of effective techniques, by engineers conversant with
modern methods of noise control;
b.
Provide information on any measures needed to keep noise under control when the machine is used.
INFORMATION AND TRAINING FOR EMPLOYEES
Current regulations require all employees subject to the 80 dB(A) exposure level to be provided with information,
instruction and training.
This should include:

the likely noise exposure and the risk to hearing noise creates.

how to report defects in ear protectors and noise control equipment.

where and how ear protectors can be obtained.

the employees duties under current regulations.

what the employee should do to minimise the risk, such as the proper way to use ear protectors and
other equipment, how to look after it, and where ear protectors should be used.
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