Before noise can be controlled, it must be assessed. A noise risk assessment finds out who is exposed to noise, how much noise they are exposed to, and what must be done about it.

In this module, you will learn when a noise assessment is needed, what it involves, who should carry it out, and how the findings lead to action.

By the end of this module, you will be able to:

• Explain when a noise risk assessment is required.
• Describe what a noise assessment involves.
• Explain who should carry it out.
• Describe how noise is estimated and measured.
• Explain how the findings lead to an action plan.

Where work is likely to expose anyone at or above the lower exposure action value of 80 dB(A), the employer must make a suitable and sufficient noise risk assessment.

Signs that an assessment is needed include people raising their voices to talk, the use of noisy tools, or a workplace that is noisy for much of the day.

A noise risk assessment should:

• Identify where there may be a risk from noise, and who is likely to be affected.
• Estimate or measure workers’ exposure, and compare it with the action and limit values.
• Identify what needs to be done to comply with the law.
• Identify suitable noise controls and hearing protection.
• Identify any workers who need health surveillance.
• Record the significant findings, and an action plan.

The assessment must also think about workers who may be more at risk, or affected in other ways, such as:

• Young workers and new starters, who may not recognise the danger.
• Workers who are particularly sensitive to noise, such as those who already have some hearing loss.
• Workers who are also exposed to vibration or to certain chemicals that can affect hearing.
• People who need to hear warning signals, alarms or vehicles to stay safe.

The noise risk assessment must be carried out by a competent person: someone with the training, knowledge and experience to estimate or measure noise correctly, and to understand the results.

Where measurements are needed, they must be taken with suitable, calibrated instruments, by someone who knows how to take readings that truly represent the work.

Exposure can sometimes be estimated without measuring. The competent person uses the noise information that manufacturers must supply for their tools and machines, and combines it with how long each one is used in a typical day.

Published noise data for similar tasks can also help. But where the estimate is uncertain, or exposure may be close to an action value, measurement is needed.

Noise can be measured with:

• A sound level meter, held near the worker’s ear while each task is carried out.
• A personal noise dosimeter, a small meter worn by the worker for the whole shift.

Readings must reflect a realistic working day, including the noisiest tasks, any peak noises, and the time spent on each task.

Workers know best which tasks are noisiest, how long they take, and where problems occur. They should be consulted during the assessment.

Their safety representatives should also be involved. Workers must be told the results of the assessment, the likely level of their exposure, and what is being done to reduce it.

An assessment is only useful if it leads to action. The findings should be turned into an action plan that:

• Gives priority to reducing noise at source.
• Sets out the controls and hearing protection needed.
• Identifies who must have health surveillance.
• Gives clear responsibilities and timescales for each action.

The plan should be followed up, to check that the controls are actually working.

The noise assessment must be kept up to date. It should be reviewed regularly, and whenever there is reason to think it is no longer valid, for example:

• New machines, tools or processes are introduced.
• Working patterns, shift lengths or the workplace layout change.
• Health surveillance shows that someone’s hearing is being damaged.
• Controls have been improved, and their effect needs checking.