Noise at work: when a survey becomes a legal requirement
MGS Safety team · 1 min read
Lower and upper exposure action values explained, plus when you are legally required to act — and when a formal noise survey is the sensible answer.
Noise is one of the most common causes of occupational ill health in the UK, and one of the easiest risks to overlook because the damage happens slowly.
The regulations set three levels of exposure to daily or weekly average noise. Each one triggers a different obligation.
The three thresholds
- Lower exposure action value — 80 dB(A). You must assess the risk, provide information and training, and make hearing protection available on request.
- Upper exposure action value — 85 dB(A). Hearing protection becomes mandatory, the area should be marked as a hearing protection zone, and health surveillance is required for those exposed.
- Exposure limit value — 87 dB(A). This is the level that must not be exceeded, taking hearing protection into account.
There are peak values too, which matter in workplaces with impact noise.
When a noise survey is needed
A formal survey is the reliable way to know where you sit. It becomes necessary when:
- noise levels are uncertain and you cannot confidently rule out exposures at or above the action values
- you have already had to issue hearing protection as a precaution
- employees report difficulty hearing conversation at normal volume over background noise
- processes involve impact, percussive or high-pitched sound
What a survey gives you
Done properly, a survey gives you measured exposure for each role, a map of where the noise is coming from, and a clear list of controls — usually engineering first, hearing protection last. It also gives you the evidence to show you have discharged your duty.
If you suspect noise is a problem but are not sure whether you have crossed a threshold, that uncertainty is itself a good reason to measure.
