New HAV legislation
August 1st 2004

Hand Arm Vibration (HAV) the transmission of vibration from power tools and machinery into the hands and arms of the operator - is one of the most important health and safety issues. There are various health risks associated with HAV, the most widely known is vibration white finger, whereby nerve endings are damaged due to excessive vibration. This has caused high levels of concern across the industry, with some 300 000 sufferers in the UK alone.

In 2005 a new European Directive will regulate the amount of vibration to which a worker can be exposed. While this will be a much-needed benchmark in terms of safety, employers may understandably be concerned as to the impact it will have on productivity. However, by implementing a HAV risk management programme, workers can avoid high vibration and in turn, reduce the impact that it has on their health and the job in hand.

Regular servicing of power tools and the quality of the grinding or cutting disks used are crucial factors in minimising vibration. Risk could also be substantially increased if the tool used is not right for the job. Power tool manufacturers like Bosch take into account factors such as typical users, comfort and general application and this results in products specifically designed to minimise vibration problems. One recent introduction by Bosch is a large angle grinder.

Bosch Power Tools training and development manager, Eric Streuli, said: Health and safety at work is an issue that we take very seriously and, in construction and the allied trades, vibration is one of the most difficult to control. Bosch has designed its angle grinder to exceed the proposed 2005 regulations, hence reducing the risk to the user and ensuring value for money through no limit on tool working time.

Made from an elastic material, the vibration control feature is connected with a fastening ring to the motor housing and with an adapter ring to the handle. This acts as a damping unit, meaning the motor housing is disconnected from the handle and therefore reduces vibration being transmitted to the user. Research and development combined the best elements of previous models making it the safest large angle grinder on the market in terms of vibration.

However, we also acknowledge that we have a responsibility as a manufacturer to educate users so they can feel confident about choosing the right tool for the job. A statement of the vibration level associated with your Bosch tool is available from us.

Advice from the (HSE) is that health and safety officers should check the following:

Likely vibration magnitudes for your intended uses

Risks from other hazards such as dust and noise

Any warning in the instruction booklet if particular uses are likely to cause high levels of vibration

Factors such as weight of tool, handle design and comfort, grip force required and the ease of use

Where manufacturers declare their levels to be less than 2.5m/s2, check if these are workplace levels.

The HSE has no current specific guidelines for vibration measurement because of the wide variety of applications and products. This is why, according to current standard EN50144, vibration is measured in a laboratory with no load and a standardised, unbalanced aluminium disc. Vibration is measured in units of metres per second per second (m/s2), which relates to the vibration magnitude in terms of acceleration. The HSE advises that if an operator is using a power tool for all of a working day then the tools vibration level should not exceed 2.8 m/s2. The new European regulations will reduce this to 2.5m/s2.

According to Eric Streuli, it is vital that all power tool users are made aware of these measurement levels: While it may seem a little confusing at first, it is worth getting to grips with the terminology ahead of the proposed 2005 regulations.

At Bosch we have had our new grinder independently tested by the Industrial Noise and Vibration Centre. Discussions with the Centre mean we understand more fully the practical implications of the tools performance. To standard EN50144 the new anti-vibration grinder gives a reading of 1.7m/s2 whereas a grinder without vibration damping elements gives a reading of 5.5m/s2.

Overcoming health and safety risks and maximising productivity is the ultimate aim for the construction industry. This can be achieved by manufacturers, health and safety officers and tradesmen operating together in a safe working environment. For further information on hand-arm vibration visit www.hse.gov.uk/vibration.