Sounding Off
The Control of Noise Regulations 2005 came into force on 6th April 2006. They require employers to take a modern risk management approach to noise in the workplace.
These Regulations revoke and replace the Noise at Work Regulations 1989.
A Medical Research Council survey in 1997-98 gave a prevalent estimate of 509,000 people in Great Britain suffering from hearing difficulties as a result of exposure to noise at work. This is much larger than the estimate from the HSE’s self-reported work-related illness surveys. According to the most recent of these, in 2004/05 an estimated 74,000 people in Great Britain believed they were suffering from a hearing problem that was caused or made worse by their current or past work.
The main health effect of exposure to noise is Noise Induced Hearing Loss (NIHL). NIHL is a permanent, irreversible condition.
Hearing loss is usually gradual because of a prolonged and regular exposure to noise. Sufferers may only realise how deaf they have become when damage caused by noise over the years combines with hearing loss due to ageing. Signs of this process may be their family complaining about the television being too loud, not being able to keep up with conversations in a group, or having trouble using the telephone. Eventually everything becomes muffled and sufferers find it difficult to catch sounds like ‘t’, ‘d’ and ‘s’, so they confuse similar-sounding words.
Hearing loss is not the only problem, people may develop tinnitus (a ringing, whistling, buzzing or humming in the ears), a distressing condition which can lead to disturbed sleep.
In a research report commissioned by the HSE in 2003 entitled ‘Analysis of Compensation Claims Related to Health and Safety Issues’, of the compensation claims examined, 37 (7.6%) cases involved exposure to noise. The injury type sustained in all cases was deafness/hearing loss. Of the 37 cases examined, 25 (68%) are known to have been successfully settled. The amount of compensation paid ranged from £586 to £5,458 with a mean amount value of £1,782. The mean time for cases to be settled was 42 months.
Work related noise-induced hearing damage is entirely preventable. The following measures are instrumental in this:
| • | employers must take action to reduce exposure to noise and provide protective measures for employees; |
| • | manufacturers must design tools and machinery to operate more quietly; and |
| • | employees must make use of the protective measures supplied. |
The Noise at Work Regulations 1989 had two action levels relating to daily personal exposure, averaged out over an eight hour day. 85dB(A) was the first action level and 90dB(A) was the second. There was also a peak action level of 140dB(A) associated with high intensities of noise, e.g. a jet engine or explosion, where there is an instant risk of hearing damage.
The Control of Noise Regulations 2005 replace the original action levels, as follows:
| • | lower exposure action values - a daily or weekly personal noise exposure of 80dB(A) and a peak sound pressure of 135dB(C); |
| • | upper exposure action values - a daily or weekly personal noise exposure of 85dB(A) and a peak sound pressure of 137dB(C); and |
| • | exposure limit values - a daily or weekly personal noise 87dB(A) and a peak sound pressure of 140dB(C). |
The new regulations mean that employers are required to do the following:
| • | assess the risks to your employees from noise at work; |
| • | take action to reduce the noise exposure that produces those risks; |
| • | provide your employees with hearing protection if you cannot reduce the noise exposure enough by using other methods; |
| • | make sure the legal limits on noise exposure are not exceeded; |
| • | provide personal hearing protectors upon request at the lower exposure action values and compulsorily at the upper exposure action values; |
| • | designate hearing protection zones where an employee is likely to be exposed to noise at or above an upper exposure action value; |
| • | ensure that equipment, including personal hearing protectors, is fully and properly used and maintained in an efficient state, in efficient working order and in good repair; |
| • | ensure employees make full and proper use of personal hearing protectors and any other control measures; |
| • | carry out health surveillance where there is a risk to health; and |
| • | provide employees with information, instruction and training |
Employers in the music and entertainment sectors have until 6th April 2008 to comply with the Noise Regulations 2005. Meanwhile they must continue to comply with the Noise at Work Regulations 1989, with the 2005 Regulations replace for all other workplaces.
The Regulations do not apply to:
| • | members of the public exposed to noise from their non-work activities; |
| • | those making an informed choice to go to noisy places; and |
| • | low-level noise which is a nuisance but causes no risk of hearing damage |
Noise Control
These new regulations are concerned with controlling noise, not measuring it! We have outlined some examples of how to practically control noise courses:
• engineering controls – purchasing equipment which has low vibration and noise characteristics;
• orientation and location – moving the noise source away form the work area, or turning the machine around;
• enclosure – by surrounding the machine or other noise source with sound-absorbing material;
• use of silencers – these can suppress noise generated when air, gas or steam flows in pipes or is exhausted to the atmosphere;
• lagging – this can be used on pipes carrying steam or hot fluids as an alternative to enclosure;
• damping – this can be achieved by fitting proprietary damping pads, stiffening ribs or by using double skin construction techniques;
• screens – these are effective in reducing direct noise transmission;
• absorption treatment – in the form of wall applications or ceiling panels;
• isolation of workers – in acoustically-quiet booths or control areas which are properly enclosed; and
• personal protection – the provision and wearing of ear muffs or plugs. This must be regarded as the last line of defence, and engineering controls should be considered in all cases. Areas where personal protective devices must be worn should be identified by signs, and adequate training should be given in the selection, fitting and use of the equipment, as well as the reasons for its use.
Example of a noise problem
The problem – Metal on metal impacts are a common and often a disproportionately significant source of noise in many metal fabricating shops.
One major motor manufacturer recently installed a cropping machine to automate the finishings of castings, previously carried out by operators using hand-held pneumatic tools.
While the new equipment reduced noise exposure during the process itself, noise was still being generated by the unloading mechanism. A mechanical arm lifted the casting out of the machine, rotated it clear and then dropped it from a height of about one metre into a metal chute. The impact of the components onto the chute created peak noise levels of 100dB(A).
The solution – A 5mm layer of wear-resistant rubber matting was applied to the inner surface of the chute.
The cost – About £75 per square metre for the material, plus installation.
The result – A noise reduction of about 15dB.
The idea that hearing protection always solves the noise problem is false and constantly purchasing replacement protectors produces an ongoing cost. Employers should instead concentrate on practical measures that can be taken to protect their employees, i.e. reducing noise exposure by developing a strategy for prioritising, planning and implementing noise exposure controls.
The new regulations are a further attempt by the Government to reduce the amount of industrially created hearing loss experienced by employees.
The intention of these regulations is to control the noise at “source” rather than protecting the employees hearing via various protection methods, e.g. hearing protectors.
By utilising an effective purchasing policy (where noise output on machinery is considered) and developing effective engineering controls to reduce noise sources, reduces the reliability on personal protective equipment.
The provision of sound barriers or enclosures around noisy equipment can have a significant impact in reducing noise in the workplace. We have often identified in industrial workshops and warehouses the greatest source of noise affecting hearing is the “radio”, an item often missed as a source of noise that can impact on employees’ noise exposure.
An effective risk assessment approach concentrating on controlling the main noise sources first is strongly recommended.