Quick answer
Assess who is exposed, how much and for how long, then reduce noise at source and through suitable work arrangements. Provide appropriate hearing protection, information and health surveillance where required. Compare exposure with the relevant daily/weekly and peak criteria, not just a single reading.
Why a machine’s loudness is only part of the risk
Exposure depends on the work and the time people spend around different sources. HSE’s employer noise guidance requires assessment, risk reduction and the relevant protective arrangements.
Include normal operation, cleaning, maintenance and nearby workers. Consider whether noise masks warnings or communication. Obtain competent assessment where the exposure or required controls are uncertain.
Read GB action and limit values as exposure criteria
| GB criterion | Daily or weekly exposure | Peak sound pressure |
|---|---|---|
| Lower action value | 80 dB(A) | 135 dB(C) |
| Upper action value | 85 dB(A) | 137 dB(C) |
| Exposure limit value | 87 dB(A) | 140 dB(C) |
These are the values listed by HSE. They describe different criteria and associated duties; weekly assessment is not a licence to average away any unsafe exposure.
HSE’s regulatory explanation accounts for hearing-protection reduction when applying the exposure limit, rather than using it to disregard the action values. A momentary phone-app reading does not establish compliance with these exposure criteria.
Reduce the noise before relying on personal protection
Consider a quieter process or equipment, competent enclosure or engineering changes, maintenance and separation of people from the source. Assess the whole effect, including any new safety, access or process risks.
Plan the remaining work to reduce exposure where appropriate. Select suitable hearing protection for the assessed conditions and ensure correct use. Simply issuing ear defenders does not demonstrate that the overall noise-control duties have been met.
Explain the controls and arrange required hearing checks
Workers need to understand the hazards, the controls they must use and how to report a problem. HSE’s duties include information, training and health surveillance where required. Use competent occupational-health advice for the surveillance arrangements; this article does not diagnose hearing loss.
NI employers should follow HSENI’s noise guidance and the NI 2006 regulations. The GB table is not a substitute for checking the applicable NI duties.
Example: a new production arrangement changes exposure
A food manufacturer adds another item of equipment beside a packing position. The manager reviews the combined work pattern and affected people rather than relying only on the new machine’s advertised data.
The action plan considers source controls, layout and exposure, then assigns implementation and a check of effectiveness. Any hearing-protection or surveillance needs are considered through the assessment.
Common mistakes
- Checking one source while ignoring the rest of the shift.
- Treating protection as the first and only control.
- Confusing dB(A) exposure and dB(C) peak criteria.
- Waiting for reported hearing difficulty before managing a known risk.
Next steps
Identify potentially noisy tasks and affected workers, obtain competent exposure assessment where needed and record a prioritised control plan. Verify the result and review after relevant equipment or work changes.
Use HSE’s noise-assessment and control guidance — Technical exposure assessment, hearing-protection selection and surveillance need suitable competence beyond a general awareness course.