Confusion over tool vibration

Startling new research has highlighted the vast discrepancy between the vibration performance of different manufacturers’ tools when performing the same tasks.

As the Control of Vibration at Work Regulations come into force on 6 July, the research shows that m&e contractors should choose their tools very carefully when considering compliance with the new regulations.

Work at Loughborough University’s Off-highway Plant and Equipment Research Centre (OPERC) on hand-arm vibration from tools in real work situations highlighted a wide range of performance from different manufacturers. The results gave “frightening indications”, according to Walid Hussain, product specialist at tool supplier Hilti.

Tool manufacturers often quote vibration performance to BS EN 50 144, a laboratory standard intended for comparison of different tools (see EMC, May 2005, pages 41-42). The OPERC study is based on BS EN 5349, which takes into account real life performance in a variety of tasks.

“The results are alarming,” said Hussain. “Some of the battery tools tested have a vibration performance just as high as a heavy-duty breaker.” He advises contractors to look at light-duty tools such as battery drills very carefully as the research shows a high level of vibration.

The new regulations will impose tough limits on tool vibration. Assuming an eight-hour working day, employers need take no action if the tool vibration is less than 2·5 m/s2 – the exposure action value. Above this, the employer must have a programme of actions to control risk, with an absolute cut off of 5 m/s2 – the exposure limit value.

OPERC’s measurements of vibration at the handles of the tools showed that all tools exceed the eight-hour exposure action value. They looked at how much work could be done before the limit was reached. For battery drills, Tool A could drill more than twice as many 12 mm diameter holes as Tool C.

“When assessing tools, make sure the data is actually representative and challenge the manufacturer’s data,” advises Hussain. Hilti will send a team of engineers out on site and work with contractors to take measurements to BS 5349.