Occupational Vibration Measurement and Assessment

In the area of Occupational Vibration Measurement and Assessment Scenic Acoustic and Vibration Engineering Ltd (SAVE) have a vast experience in the assessment of vibration exposure to Human beings caused by exposure to Hand Arm Vibration (HAV) and Whole Body Vibration (WBV). Hand-arm vibration syndrome (HAVS) is a widespread occupational health problem. It has been estimated that there are 36,000 people with advanced stage of Vibration White Finger (VWF) and hundreds of new cases are reported each year.

Following high profile cases such as the British Steel Industry in the 1990’s, HAVS is currently one of the most common reasons for occupational ill health claims against employers. SAVE are very experienced in performing HAVS Risk assessments, measurement of tri-axial vibration levels produced by tools and processes, calculating employee exposure levels and recommending employees at risks from HAV and WBV for additional health surveillance. SAVE can create a HAVS Management Plan which allows close monitoring of and auditing of all aspects of noise and vibration exposure. A HAVS Management Plan provides all the steps required for the successful management of ‘At Risk’ employees, ‘High risk’ working areas, ‘High Risk’ work activities and procedures, vibration measurement schedules, personnel work patterns and working areas, estimation and calculation of exposure levels, and the selection of tools and their maintenance regimes in accordance with Provision and Use of Work Equipment Regulations 1998 (PUWER).

In severe cases VWF or HAVS can be a very disabling condition, resulting in amputation of fingers, inability to perform simple tasks (dealing with buttons, shoelaces and many other day to day tasks). Like noise, the effects are cumulative and irreversible. Unlike noise, the use of simple personal protective equipment is not an option. Anti-vibration Gloves do not work. They do not reduce vibration amplitudes. In fact it has even been shown that they can amplify vibration amplitudes at some frequencies which are coincident to the natural frequency of the gloves themselves.

EC Directive on Physical Agents (Vibration) became law in the UK in July 2005 with the Control of Vibration at Work Regulations 2005. The Directive deals not only with hand-arm vibration, but also whole body vibration. Typical activities resulting in vibration exposure include:-
• Use of vibrating hand tools, including jack hammers, chipping hammers, drills, grinders, sanders, nut runners, riveting hammers, strimmer’s, chain saws etc.
• Holding vibrating work pieces while grinding, finishing, sanding, drop forging and stamping.
• Use of hand guided equipment, e.g. lawnmowers, floor polishers, impactors.
• Whole body vibration from driving of construction, mining and quarrying plant, agricultural machinery etc.

Although HSE advice is that employers do not necessarily need to carry out vibration measurements provided a reasonable estimate of exposures can be made from other sources (e.g. manufacturers’ information, available data from HSE or a number of websites). However they also note that shortfalls and poor assessment of actual exposure levels can be significantly under estimated. The reason for this is that manufacturers’ data can be misleading and often underestimates exposure, and vibration values can vary widely depending upon particular local conditions, individual techniques of operatives etc. The test methods adopted by the manufacturers and suppliers do not take into account the ‘Real World’ ergonomics of using the tool, or the orientation of the equipment when it is being used in the ‘Real World’. Many tests rely on a simple vibration measurement whilst the tool or equipment is suspended from rubber hanger. Insurers are likely to regard actual workplace measurements as more reliable and more useable as a defence against claims in the future.