A noise reading beside one machine does not, by itself, show an employee's daily exposure or prove the risk is controlled. Employers need to understand the work, the duration and pattern of exposure, peak sounds, the people affected and the measures that can reduce noise at source.
Start with exposure, not a single sound reading
The Control of Noise at Work Regulations 2005 require a suitable and sufficient assessment where employees are likely to be exposed at or above a lower exposure action value. That assessment is more than taking measurements. It must identify what needs to be done to comply with the law and protect employees from noise-induced hearing loss, tinnitus and other harm.
The headline values relate to daily or weekly personal exposure and peak sound pressure. A spot reading does not include task duration, frequency or other noisy work during the shift. Two employees beside the same tool can have different exposures because their work patterns differ.
Measurements are not always required. Reliable manufacturer, task and exposure data may be enough. Where uncertainty is material, a competent person should plan representative measurements.
What the 80, 85 and 87 dB values actually trigger
The values are not three interchangeable 'safe limits'. They mark different legal duties. Daily or weekly exposure is expressed as dB(A); peak sound pressure is expressed as dB(C).
An employer should not wait for 85 dB(A) before assessing and controlling a foreseeable risk. The lower value already triggers duties, while regulation 6 requires exposure to be eliminated at source or reduced to as low a level as reasonably practicable.
- Lower exposure action values — 80 dB(A) daily or weekly exposure and 135 dB(C) peak sound pressure: assess the risk, eliminate or reduce it so far as reasonably practicable, provide information and training, and make suitable hearing protection available where employees request it.
- Upper exposure action values — 85 dB(A) daily or weekly exposure and 137 dB(C) peak sound pressure: establish and implement a planned programme of technical and organisational controls, designate hearing-protection zones where appropriate, provide suitable protection and ensure it is used. Health surveillance is required for employees regularly exposed above the upper values, or otherwise at risk.
- Exposure limit values — 87 dB(A) daily or weekly exposure and 140 dB(C) peak sound pressure: these must not be exceeded. Unlike the action values, the attenuation provided by personal hearing protection may be taken into account when judging exposure against the limits.
HSE: employers' responsibilities for noise ↗ · Control of Noise at Work Regulations 2005 ↗
Recognise a possible noise problem before measuring
Simple observations can help decide whether a more detailed assessment is needed. Noise may be around 80 dB where it is intrusive but normal conversation remains possible at two metres. It may be around 85 dB where people must shout to speak at two metres for part of the working day. Regular hammering, impact tools, compressed air, cutting, grinding or noisy machinery are also warning signs.
These are screening indicators, not proof that exposure is below an action value. A Teesside fabrication business might use a grinder for short bursts and an impact process less frequently. Its assessment must combine sound level, duration and pattern.
Build a suitable and sufficient assessment
Map the noisy tasks, the people exposed and anyone at particular risk. Record credible durations, shift patterns, maintenance or cleaning work, peak events, controls and movement between areas. Contractors, apprentices and employees with existing hearing damage or unusual sensitivity may need specific consideration.
Estimate exposure using reliable information and compare it with both action values and the exposure limits. HSE's daily and weekly exposure calculators can help combine tasks, but the inputs still need to be representative. A phone application may flag a concern; unless its accuracy and method are suitable, it is not a substitute for competent measurement.
Finish with a prioritised action plan: the control, owner, deadline and method of checking effectiveness. Record what information and training employees need, whether hearing-protection zones are required and whether health surveillance applies. Review the assessment when evidence suggests it may no longer be valid or when the work materially changes.
Turn noise data into a control plan.
HR + SAFETY can map noisy tasks, estimate or measure exposure and prioritise engineering, organisational and hearing-protection controls.
Discuss a workplace noise assessmentControl noise at source before relying on ear defenders
First consider whether the noisy operation can be removed or redesigned. Then examine quieter equipment and processes, enclosure or isolation, damping, silencers, screens, distance, layout and effective maintenance. Organisational measures such as limiting time or access can support those controls, but should not replace a reasonably practicable engineering solution.
Compare declared noise information before buying machinery. Installation also matters: vibration transmitted through a bench or structure may make equipment substantially noisier in use.
Hearing protection is important where residual risk remains, while better controls are developed or during occasional high-noise tasks. It is not an alternative to reducing noise at source. If work equipment is deteriorating or its guards, bearings or extraction have changed, also review the inspection and maintenance regime.
Choose hearing protection without overprotecting
Select protection for the actual frequencies and exposure, aiming to reduce noise at the ear to below 85 dB. Avoid excessive attenuation that isolates the wearer or prevents communication; HSE advises against reducing the level at the ear below 70 dB. Provide a suitable choice where possible and check compatibility with helmets, eye protection, respirators and other PPE.
Fit, condition and use determine real protection. Employees need instruction on when protection is required, how to fit and check it, storage, hygiene, replacement and defect reporting. Supervisors must enforce use in hearing-protection zones and make sure alarms and safety-critical communication remain effective.
Provide health surveillance where the risk requires it
Provide suitable health surveillance for employees who are likely to be regularly exposed above the upper action values, or who are at particular risk. This usually includes hearing checks—often called audiometry—under the direction of an occupational-health professional with appropriate competence.
A useful programme establishes a baseline, repeats checks at suitable intervals and identifies trends that may show controls are failing. Medical information remains confidential, but the employer needs enough fitness and risk information to act. Deterioration should trigger investigation and review, not simply another set of ear defenders.
Eight decisions for a practical noise action plan
The finished assessment should allow a manager to see who is exposed, why the estimate is reliable, what will reduce the risk and how the business will know whether the controls are working. A decibel table without decisions is not a control programme.
- List the noisy tasks, their duration, frequency and peak events.
- Identify everyone exposed and anyone at particular risk.
- Estimate daily or weekly exposure using reliable, representative data.
- Decide where competent measurement is needed to resolve uncertainty.
- Prioritise elimination, quieter methods and engineering controls.
- Define hearing-protection zones and suitable protection for residual exposure.
- Provide information, training, supervision and health surveillance where required.
- Review after equipment, layout, processes, shifts, complaints or hearing results change.
The 80 dB(A) lower action value triggers assessment, control, information and access to hearing protection; 85 dB(A) brings additional control, zone, use and surveillance duties; and 87 dB(A) is a limit that must not be exceeded after allowing for protection. The objective throughout is to eliminate noise at source or reduce exposure as far as reasonably practicable.
This guide provides general information for UK employers. It is not legal advice and should not replace advice based on the facts of a specific matter.