Vibration

Vibration is encountered in many trades, principally where hand held tools and equipment, often powered by compressed air, are used to cut or shape metal or break up hard surfaces such as tarmac or concrete. The use of vibrating tools can give rise to a condition known as Hand Arm Vibration Syndrome (HAVS) or Vibration White Finger (VWF)

(Note: The drivers of plant and equipment, especially that used "off road" in quarries or on construction sites can also be exposed to vibration. This can give rise to effects usually described under the heading of Whole Body Vibration.)

Hand Arm Vibration Syndrome: Over exposure to vibration will result in damage to the nervous system and the blood vessels in the hand leading to numbness and tingling, a loss of sensation and blanching or whitening of the fingers. The blanching often occurs when the hands are exposed to low temperature, for example when going out of doors. The condition is progressive, gradually worsening as exposure continues until serious disability occurs with an inability to undertake "fine" tasks, to cope with buttons and fastenings and adverse effects on hobbies e.g. fishing or working out of doors.

The tools and equipment most commonly associated with HAVS include:

Pneumatic jackhammers and chipping hammers
Grinders
Riveting tools

Factors such as the length of time for which the tool is used, its state of repair and maintenance, the sharpness of the bit, the working posture and whether the working environment is cold all contribute to the degree of risk. An assessment of the risk of HAVS should include the following:

Securing manufacturers data on the vibration produced by the equipment.
Determining the working methods - how long the equipment is used, the posture, temperature etc
Seeking information from employees regarding any ill effects noticed.
As a last resort taking measurements of vibration.
Vibration is measured in metres per second per second, usually written as m/s2 or ms2. As a general rule the higher the number the greater the risk.

The reduction of the risk of ill health from exposure to vibration will involve a number of actions including:

Seeking alternative methods of working e.g. replacing manual road breakers with attachments for JCBs or similar
Replacing old, worn equipment with new tools
Maintaining tools in good repair and ensuring that bits and chisels or similar are kept sharp
Fitting vibration reducing grips or isolators where appropriate (not a 100% effective solution but can give some benefits)
Ensuring the most effective working methods are adopted i.e. that the tool is used correctly
Reducing employee exposure by job rotation
Providing hand protection e.g. gloves (less to isolate the employee's hand from vibration more to keep hands/fingers warm)
Wherever possible, keeping the workplace warm and dry (this helps maintain a steady blood supply to the extremities)
Providing employees with training and information about the risks
Considering the introduction of health surveillance where it is thought that damage is taking place