Comparing measurements with recognised limits

The EU Directive 2002/44/EC sets minimum requirements implemented through national law. Great Britain's Control of Vibration at Work Regulations 2005 use the A(8) values below. A(8) is exposure normalised to eight hours, not a requirement that every shift lasts eight hours. Estimate vibration magnitude and actual exposure time, combining relevant tools or tasks. An action value triggers action; neither it nor a limit is a guarantee of no health risk.

The employer must:

• assess the vibration risk to employees
• act to reduce the exposure that creates those risks
• decide whether employees are likely to be exposed above the legal values
• make sure the legal limits are not exceeded
• give employees information and training on the health risks and on the actions being taken to control them
• carry out health surveillance (regular health checks) where there is a risk to health
• consult the trade union safety representative or employee representative on proposals to control the risk and provide health surveillance
• keep a record of the risk assessment and of the control actions
• keep health records for employees under health surveillance
• review and update the risk assessment regularly

Basic vibration control measures

Employers must take action to prevent risk from vibration. They should first ask whether other methods or machines would remove the exposure altogether, especially where large shocks and jolts are involved. If that is not possible, exposure should be reduced to as low a level as is reasonably practicable.

Many control measures exist, though not all suit every workplace. What suits depends on the characteristics of the vibration (its size, its source and whether it is intermittent or constant) and the characteristics of the workplace.

Alternative methods of working. Wherever possible, remove or reduce the vibration. Consider:

• designing out unnecessary vibrating tasks and using prefabricated components
• using a different process that does not expose workers, for example block splitters instead of cut-off saws, or bursting or crushing instead of pneumatic drilling
• separating workers from the vibrating task, for example by using a breaker attachment on an excavator, or remote-controlled equipment, instead of a hand-held breaker

Selection of suitable equipment. Choose low-vibration tools, and do not buy or hire a problem if you do not have to. Make sure the tool is also right for the job, because equipment that is unsuitable, too small or not powerful enough can make the task take much longer and expose workers to needless vibration.

Maintenance programmes. Good maintenance makes a big difference to vibration levels. Loose or worn parts create extra vibration, and blunt, damaged or inefficient tools vibrate more and also stretch the task out, which increases exposure. Introduce suitable maintenance programmes to prevent avoidable increases, following the manufacturer's recommendations where appropriate.

Limiting exposure time. Reduce actual tool-contact time and avoid long uninterrupted exposure, while controlling total daily exposure. Several short periods can still add up to excessive exposure. Rotation helps only if the alternative tasks reduce exposure; moving between vibrating tools does not reset the daily dose.

Suitable PPE. Provide protective clothing if needed to keep workers warm and dry, because keeping the core body temperature up encourages good blood circulation. Gloves keep the hands warm, but they give no protection against vibration.

The role of health surveillance

For hand-arm vibration, provide suitable health surveillance where the assessment and applicable requirements identify a need, including relevant regular exposure at or above the action value or particular susceptibility. HSE does not recommend the same routine surveillance programme for whole-body vibration. It also helps stop disease progressing, helps people stay in work and checks whether the controls are effective. Its main purposes are to:

• identify anyone exposed, or about to be exposed, who may be at particular risk, for example people with circulatory diseases such as Raynaud's disease
• identify any vibration-related disease at an early stage in employees regularly exposed to hand-arm vibration
• help prevent disease progression and eventual disability
• help people stay in work
• check the effectiveness of the vibration control measures

Summary notes for Element 5 · Cheat sheet · Glossary. A study aid, not published or endorsed by NEBOSH.