HAV (Hand Arm Vibration) Measurement, refers to the process of carrying out Risk Assessments on employees who are likely to come into contact with Hand Transmitted Vibrations (HTV) or are involved in repetitive actions. These can often lead to injury, absence and ever-increasing compensation for recognised industrial diseases such as Vibration White Finger (VWF).
Vibration in industry is likely to become an area of statute, much in the same way as COSHH and Noise at Work. There is already a proposal for legislation which includes Noise, Vibration, Optical Radiation and Fields and Waves, as well as HSE guidance notes.
Method
HARM is measured by establishing an 8-hour Vibration Exposure A(8), using a Vexio HAV Vibration Meter.
A(8) daily exposure to HARM is basically a frequency weighted RMS value of the vibration acceleration based on an 8-hour working day.
To measure vibration, a physical contact is normally made with a vibrating surface, this is done with an accelerometer, which is a piezoelectric crystal mounted usually in a metal block with a connector on the outside. When there is movement (vibration), the crystal creates a small electric current which is then measured to gauge the level of vibration.
There are 2 limits for exposure to HAV
2.5m/s² A(8)
This is the Exposure Action Value (EAV). This level is based on an average RMS weighted acceleration level over an 8 hour day A(8).
5.0m/s² A(8)
This is the Exposure Limit Value (ELV). This action limit value must not be exceeded within an 8 hour period.
Eagle Safety and Environment Limited IOSH-qualified HAV surveyors can undertake detailed measurements of all equipment and provide recommendations within the report, on reducing levels/replacing equipment etc, to reduce risks to employees.