Why control noise emissions from machines?


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Jeremy Procter, a member of international and UK standards committees ISO/TC 199/WG 6 (Safety distances and ergonomic aspects) and BSI MCE/3 (Safeguarding of machinery), and Managing Director of Procter Machine Guarding explains why it is important to control noise emissions from machines.

Caption: Machine builders supplying new machinery, as well as employers whose workers use existing machinery, have legal and moral obligations to manage noise.

Why control noise emissions from machines?
Jeremy Procter, a member of international and UK standards committees ISO/TC 199/WG 6 (Safety distances and ergonomic aspects) and BSI MCE/3 (Safeguarding of machinery), and Managing Director of Procter Machine Guarding explains why it is important to control noise emissions from machines.

Excessive noise can cause irreversible damage to hearing. This can be as a result of sudden extreme noises or the damage can be cumulative due to long-term exposure to excessive noise. Total or even partial deafness can be very disabling because it impairs the ability to converse or use a telephone. Another common hearing problem that can be triggered by excessive noise is tinnitus, a condition in which the sufferer perceives ringing, buzzing or humming sounds; it can be distracting during the day and disturb sleep at night. According to the HSE (Health and Safety Executive), around 17,000 people in the UK suffer deafness or other ear conditions caused by excessive noise at work.

Further problems relating to excessive noise in the workplace include stress and fatigue, and a noisy environment can contribute to accidents in that warnings and approaching hazards cannot be heard.

Not all machines are excessively noisy, but there are some types that are often problematic, many of which are used for processing metals: power presses, CNC punch presses, metal cutting saws, grinders, guillotines and riveting machines. Other areas where noise can be excessive range from bottling lines to discharge chutes, and from compressors to bowl feeders.

Machinery is a major cause of workplace noise, so reducing noise from machinery can be a vital element in reducing workplace noise overall. The responsibility for reducing machine noise is divided between machine builders (or importers) and employers who provide machinery for employees to use. We will look at each group’s responsibilities in turn.

Here in the UK, the European Machinery Directive 2006/42/EC was implemented by the Supply of Machinery (Safety) Regulations 2008, as amended by the Supply of Machinery (Safety) (Amendment) Regulations 2011. In order to be placed on the market – and that includes machines built in-house for use in-house – the machine must meet the Essential Health and Safety Requirements (EHSRs), the manufacturer must compile a Technical File and the machine must be CE marked. One of the EHSRs relates to noise, and there are Harmonised Standards that specify the limits for noise emissions from machinery and how to measure noise emissions. Although it is not a legal requirement to comply with the Harmonised Standards, doing so is usually the easiest way of demonstrating that the EHSRs have been met. Taking all of this together, in essence, machine builders and importers have a legal obligation to control noise emissions.

Employers’ legal obligations fall under the Control of Noise at Work Regulations 2005 (often abbreviated to the Noise Regulations) and also the Health and Safety at Work etc Act 1974 (sometimes referred to as HSWA, the HSW Act, the 1974 Act or HASAWA). As with the Supply of Machinery (Safety) Regulations, the UK Noise Regulations implement a European Directive, 2003/10/EC (minimum health and safety requirements regarding the exposure of workers to the risks arising from physical agents (noise)). The Noise Regulations require employers to eliminate or reduce the risks to employees’ health and safety arising from noise at work, while the Health and Safety at Work etc Act places a general duty on all employers ‘to ensure, so far as is reasonably practicable, the health, safety and welfare at work’ of employees. In reality, the HSE is more likely to prosecute under the Noise Regulations – and it has done so where necessary. Clearly company directors need to be aware of their obligations under the Noise Regulations, but others who should take note include production managers, health and safety managers, and maintenance managers (maintenance engineers may be working closer to machinery than operatives normally would).

In addition to the legal arguments for controlling noise emissions from machinery, there is also a strong moral argument; machine builders and employers should not subject machine operatives to an unacceptable risk of injury or harm of any kind. And neither should they rely on operatives to use ear defenders, as people are not necessarily aware of the risk of long-term exposure to excessive noise, as the effect is cumulative and not immediately apparent.

The third reason for controlling noise emission from machinery is a financial one. Although prosecutions are not commonplace, the costs associated with fighting court cases, paying fines, loss of reputation, and loss of production should the HSE serve an enforcement notice, can all add up to far more than the cost of implementing noise control measures.

Having established that machine builders and employers need to control noise emissions from machinery, this raises the question of how to do so? The latest White Paper from Procter Machine Guarding, Safety of machinery – acoustic enclosures for reducing noise emissions, outlines what is required for compliance with the UK’s Supply of Machinery (Safety) Regulations and the Noise Regulations. It presents the hierarchical approach that must be taken when reducing noise emissions and suggests ways to reduce the level of noise generated at source. Where noise remains excessive, the White Paper discusses the options for fully or partially enclosing the machine, then provides guidelines for designing acoustic enclosures and explains the importance of correct installation. In addition, there is a table of standards relating to noise emissions and measurements, plus a list of useful resources.

PDF copies of the White Paper Safety of machinery – acoustic enclosures for reducing noise emissions are available free of charge from the Downloads section of the Procter Machine Guarding website at www.machinesafety.co.uk or it can be read online. Alternatively, request a copy by telephoning or email info@machinesafety.co.uk.