Hand-arm vibrations

Background

The EC – Directive 2002/44/EC lays down minimum requirements for the protection of workers from risk to their health and safety arising or likely to arise from exposure to mechanical vibration.

The assessment of the vibration exposure is calculated in relation to a standardised 8h daily exposure value A(8). After establishing the A(8) value, this should be compared with the exposure action- and limit-values. As the Directive lays down minimum requirements, it is also vital to check legislation in each individual Member State of interest to find out if this legislation has stricter exposure values.

Depending on the daily Exposure Action Value (EAV) and the daily Exposure Limit Value (ELV), the employer has an obligation to take appropriate action in order to control the vibration exposure.

Exposure Action Value (EAV)

Whenever an operator is subjected to vibration exposure A(8) exceeding the EAV at 2.5 m/s², the employer must carry out a risk assessment of the operation and introduce control measures. For more details, see Directive 2002/44/EC and Member State legislation.

Exposure Limit Value (ELV)

In any event, workers shall not be exposed above the ELV (5.0 m/s²).

Guide

A(8) < 2.5 m/s².
Daily vibration exposure below the Action Level. No need for further measures to reduce exposure.

A(8) = 2.5 - 5.0 m/s²
Daily vibration over Action Level. Increased risk for developing vibration related diseases for the operator. See Husqvarna recommendations and Directive 2002/44/EC for guidelines to reduce hazards from vibration exposure.

A(8) > 5.0 m/s²
Daily vibration exposure exceeds the Exposure Limit Value. Reduce daily work time and/or use machine with lower equivalent vibration level.

Recommended action to bring down the vibration exposure

Use only low vibrating power tools. This recommendation could be regarded as the most important one. Vibration data can often be found in the manufacturer’s technical information.

Shorten the usage time of the tool. As the A(8) value is a function of both vibration value and exposure time, one alternative is always to cut down on the working time.

Service and maintenance of the machine. Follow the manufacturer’s recommendations. It is especially important to maintain the cutting equipment and the rotating elements that can become unbalanced due to wear.