Noise Assessment on Construction Sites: Legal Requirements & Control Measures

Construction is one of the noisiest industries in the UK. Demolition, piling, cutting, drilling, and plant operation routinely generate noise levels that can cause permanent hearing damage. Noise-induced hearing loss (NIHL) is the second most common occupational disease in the UK, and construction workers are among the most affected groups. Yet noise risk is still treated as an afterthought on many sites. This guide covers the legal requirements for noise assessment, how to carry out a noise survey, the exposure limits you must comply with, and practical measures for reducing noise on site.

The Legal Framework: Control of Noise at Work Regulations 2005

The primary legislation governing noise on construction sites is the Control of Noise at Work Regulations 2005. These regulations apply to all employers and set specific exposure limits and action values that determine what controls are required.

Exposure Limit Values and Action Values

The regulations define three critical thresholds:

• Lower Exposure Action Value (LEAV) -- daily or weekly personal noise exposure of 80 dB(A), or peak sound pressure of 135 dB(C). At this level, employers must make hearing protection available and provide information and training about noise risks.
• Upper Exposure Action Value (UEAV) -- daily or weekly personal noise exposure of 85 dB(A), or peak sound pressure of 137 dB(C). At this level, employers must reduce exposure by means other than hearing protection, designate hearing protection zones, and ensure hearing protection is worn.
• Exposure Limit Value (ELV) -- daily or weekly personal noise exposure of 87 dB(A), or peak sound pressure of 140 dB(C), taking into account any hearing protection worn. This limit must never be exceeded.

The distinction between 85 dB(A) and 87 dB(A) might seem trivial, but it is important. The 87 dB(A) limit is measured at the ear, after accounting for the attenuation provided by hearing protection. The 85 dB(A) value is measured in the environment. So if ambient noise is 95 dB(A) and the worker wears ear defenders rated at 25 dB, the effective exposure at the ear is approximately 70 dB(A), which is well below the 87 dB(A) limit. But the employer still has duties at the 85 dB(A) environmental level.

Typical Noise Levels on Construction Sites

Understanding the noise output of common construction activities helps with initial risk assessment:

• Concrete breaker / pneumatic drill -- 100-110 dB(A)
• Circular saw (cutting timber) -- 95-105 dB(A)
• Angle grinder -- 95-105 dB(A)
• Hammer drill -- 95-100 dB(A)
• Piling operations -- 90-115 dB(A) depending on method
• Excavator -- 80-95 dB(A) at operator position
• Concrete mixer -- 75-85 dB(A)
• General construction activity -- 80-90 dB(A)

At 85 dB(A), a worker can be exposed for 8 hours before reaching the upper exposure action value. But for every 3 dB increase, the permissible exposure time halves. At 88 dB(A), the limit is 4 hours. At 91 dB(A), 2 hours. At 100 dB(A), just 15 minutes. A concrete breaker operator at 105 dB(A) reaches the upper exposure action value in less than 5 minutes.

How to Carry Out a Noise Assessment

Step 1: Identify Who Is at Risk

Walk the site and identify all work activities that generate significant noise. Consider not only the operators of noisy equipment but also nearby workers who are exposed to the noise without directly creating it. A labourer working next to a concrete cutter may have higher noise exposure than the cutter operator, who is wearing hearing protection.

Step 2: Estimate Exposure

For an initial assessment, you can estimate exposure using published noise data for equipment and typical exposure durations. The HSE provides a noise exposure calculator on their website that allows you to input multiple noise sources and exposure durations to calculate daily exposure. If the estimate suggests exposures above 80 dB(A), a formal noise survey is needed.

Step 3: Conduct a Noise Survey

A formal noise survey requires calibrated equipment and competent personnel. The two main measurement approaches are:

• Sound level meter (SLM) readings -- spot measurements taken at the operator position during typical work activities. Useful for identifying noise sources and estimating exposure from specific tasks.
• Personal noise dosimetry -- a small dosimeter worn by the worker throughout the shift that continuously measures noise exposure and calculates the daily dose. This gives the most accurate picture of actual personal exposure.

The survey should be carried out during representative working conditions. Measuring noise on a quiet day when the piling rig is not operating will not give an accurate picture of typical exposure.

Step 4: Identify Control Measures

The hierarchy of noise control follows the general hierarchy of risk control: elimination, substitution, engineering controls, administrative controls, and personal protective equipment (PPE). Hearing protection should always be the last resort, not the first response.

Step 5: Record and Review

The assessment must be recorded and kept for as long as it remains relevant. It should be reviewed whenever there is a significant change in work activities, new equipment is introduced, or noise complaints are received. It should be part of your overall site safety management framework.

Practical Noise Control Measures on Construction Sites

Elimination and Substitution

• Use hydraulic breakers instead of pneumatic breakers (typically 10 dB quieter)
• Use diamond cutting blades instead of abrasive discs (significantly quieter and produce less dust)
• Specify low-noise plant in procurement -- modern excavators and generators are available with noise levels 5-10 dB below older models
• Use prefabricated components to reduce on-site cutting and drilling
• Choose pressed steel connections instead of site-welded connections where possible

Engineering Controls

• Acoustic enclosures around stationary plant (generators, compressors)
• Noise barriers between noise sources and adjacent workers
• Anti-vibration mounts on equipment to reduce noise transmission through structures
• Maintaining equipment properly -- worn bearings, loose panels, and damaged silencers all increase noise output

Administrative Controls

• Schedule noisy activities to minimise the number of workers exposed
• Rotate workers to limit individual exposure duration
• Establish hearing protection zones with clear signage
• Provide quiet rest areas for workers to recover from noise exposure
• Brief workers on noise risks during toolbox talks

Hearing Protection

When engineering and administrative controls cannot reduce noise below the upper exposure action value, hearing protection must be provided and worn. Key considerations:

• Select hearing protection with the correct noise reduction rating (NRR) for the exposure level -- over-protection is as problematic as under-protection because workers cannot hear warnings or communicate
• Ensure hearing protection fits correctly -- foam earplugs inserted incorrectly provide almost no protection
• Provide training on correct insertion and use
• Replace disposable earplugs daily and clean reusable protection regularly
• Consider communication headsets for workers who need to talk while wearing hearing protection

Noise-Related Health Surveillance

Where workers are regularly exposed above the upper exposure action value (85 dB(A)), employers must provide health surveillance in the form of audiometric testing. This involves baseline hearing tests when workers start employment or are first exposed to noise, and periodic follow-up tests (typically annually for the first two years, then every three years if hearing is stable).

Audiometric testing identifies early signs of hearing damage before the worker notices any problem. If hearing loss is detected, the worker should be referred to an occupational health physician, the risk assessment should be reviewed, and additional controls should be considered.

Records of audiometric tests must be kept for at least 40 years. This is because noise-induced hearing loss often does not become apparent until years or decades after the exposure occurred, and historical records may be needed for future claims.

Managing Noise Impact on Neighbours

Noise from construction sites also affects local residents and businesses. While the Control of Noise at Work Regulations focus on worker exposure, site managers also need to consider:

• Section 60 and 61 notices under the Control of Pollution Act 1974 -- local authorities can serve Section 60 notices restricting construction noise. Section 61 allows contractors to apply for prior consent for construction methods, which provides a defence against future complaints.
• Working hour restrictions -- most local authorities restrict noisy construction work to specific hours (typically 8am-6pm Monday to Friday, 8am-1pm Saturday, no working on Sundays and bank holidays).
• Best Practicable Means (BPM) -- the legal standard for controlling neighbourhood noise. This means using the best available techniques that are economically and technically feasible to minimise noise impact.

Good neighbour relations start with communication. Notify local residents before particularly noisy phases of work, explain the duration, and provide a contact point for complaints. This simple step prevents the majority of noise disputes.