Q&A: Noise Special


We caught up with health and safety training experts, THSP Risk Management, who provided us with the latest information on noise regulations.

What does 90 decibels sound like?

There are some simple ‘rules of thumb’ which work well with noise:

  • If you can hold a conversation at 2m distance, but the noise is intrusive, the level is around 80dB:
    This is the Lower Exposure Action Value (LEAV)
  • If you need to raise your voice to hold a conversation at 2m, the noise is around 85dB, and
    If you need to raise your voice to hold a conversation at 1m, the noise is definitely above 90dB

How do you know if you need to do a noise survey?

The Regulation 5 of the Control of Noise at Work Regulations 2005 are quite specific.

Any employer who carries out work which is liable to expose any employees to noise at or above a lower exposure action value shall make a suitable and sufficient assessment of the risk from that noise to the health and safety of those employees, and the risk assessment shall identify the measures which need to be taken to meet the requirements of these Regulations.

In conducting the risk assessment, the employer shall assess the levels of noise to which workers are exposed by means of –

(a) observation of specific working practices
(b) reference to relevant information on the probable levels of noise corresponding to any equipment used in the particular working conditions
(c) if necessary, measurement of the level of noise to which his employees are likely to be exposed

Also, if it’s noisy, it’s likely to vibrate; if it vibrates, it’s likely to be noisy

How do you carry out a noise survey?

The process sounds quite simple, measure the exposure of operatives to noise in the workplace; but in practice, this can be complex and sometimes challenging.  There is no ‘one size fits all’ solution.

For example, if a person works at the same machine all day, in a fixed location, it may be appropriate to just measure the noise at that place and calculate the exposure.

On the other hand an employer could have personnel who move around a lot, work on several different items of equipment and undertake a variety of tasks. 

On these occasions employees are fitted with Personal Dose Rate Meters (PDRM or Dosimeter) at the start of the day and allowed to work as normal.  At the end of the day the Dosimeters are collected, the data analysed and solutions or recommendations suggested.

Equipment for measuring noise is very expensive and must be calibrated annually.

Can you give an example of noise levels?

Typical machinery used in manufacturing, such as power presses, produce noise levels in the region of  85 – 87dB; angle grinders, chop saws and sheet metal works can be significantly noisier, at around
98 – 103dB.  Windy drills may produce as much as 97dB and percussion riveting up to 117dB.
Welding operations can produce noise levels in the order of 90dB but the proximity of one workstation to another can increase this to 93dB quite easily

Background noise levels in a machine shop are typically around 85dB however with the radio (turned up so everyone can hear) it may increase significantly.

What control measures can be used?

This is not an easy question to answer.  The Regulations require the employer to reduce the noise level by any means OTHER THAN hearing protection, which is to be used as a last resort.

Each solution is unique to the circumstance however there are some simple measures which can be taken to reduce noise exposure.

  • Line discharge chutes from automated machinery with rubber
  • Ensure items being cut are clamped adjacent to the blade and also at the tail to reduce vibration
  • Avoid metal on metal contact where possible
  • Keep machinery in good condition, reducing ‘play’ on worn areas or linkages
  • Consider ‘low noise’ alternatives when purchasing replacement equipment
  • Turn the radio down and provide repeat speakers at workstations
  • Identify Noise Control Zones and enforce the use of hearing protection
  • Educate your staff to look after their hearing

Are there any online resources that can help?

The HSE’s web site is extremely useful, the online exposure calculator is very handy.
Also available on the HSE web site is L108, the ACOP for the regulations and a number of other guidance publications that can be printed off for employees.

The Health and Safety Executive’s (HSE) new strategy gives the same priority to health as it does to safety. Meaning that HSE inspectors may become more attentive to employee health and wellbeing, resulting in greater use of enforcement in this area.

Don’t worry if you need help with noise assessments as THSP can help! We have Institute of Acoustics qualified and experienced consultants who carry out an assessment of exposure to noise in your workplace with the latest up to date equipment. Protecting your workers hearing and keeping you safe from HSE enforcement notices. For more information give us a call on 03456 122 144



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