EDITOR’S NOTE: The following article was originally published by the Chicago Pneumatic Expert Corner blog
Does your team use handheld power tools, such as industrial impact wrenches or grinders? Check out our seven tips to reduce their exposure to Hand Arm Vibration Syndrome (HAVS).
What is the Hand Arm Vibration Syndrome?
The Hand Arm Vibration Syndrome is recognized as a serious work-related disorder, which is affecting thousands of industrial workers. It is represented by damage to blood vessels, nerves, muscles and joints of the wrist and arm caused by intensive and repeated vibration exposure. This exposure comes from working with vibrating tools or holding shaking materials.
The repeated hits on the fingers and hands at certain frequencies constitute a risk for the workers. There is no certainty about how this happens exactly, but numerous studies show damage to the very fine blood vessels in the hands as one probable contributor to the syndrome.
What are the symptoms?
- Early symptoms: Repeated loss of feeling, numbness, in the fingertips and sensation of needles in the fingers, tingling, are early indicators. These sensations can come and go and are not proof of HAVS, but should be seen as early warnings
- Later symptoms: More severe symptoms are often felt like permanent numbness of fingers, causing difficulties in daily life when handling small objects or when buttoning for example.
When getting cold or wet, the fingers will often react by becoming white, then red while being painful. This is called the Raynaud's phenomenon, and is also common in hand arm vibration syndrome cases.
Who could be concerned by HAVS?
All frequent users of power tools that vibrate during usage could be affected. Vibration level and trigger time per work shift are the key factors that together give an indication if the person is at risk.
According to a Japanese long-term study on forest workers using chainsaws (Nagoya, 1994), there is a strong relation between the number of years of exposure and the prevalence of HAVS. Among the workers over 50 years of age, 38 percent showed signs of this syndrome.
US National Safety Council estimates that about 2 million U.S. workers are exposed to hand-arm vibration today, and as many as half could develop HAVS.
HAVS is preventable, but once the damage is done, it is often permanent.
How to manage risks in your workplace : 7 tips to reduce vibration exposure
Many measures can be taken to reduce risk. Limiting time of vibration exposure being clearly the most important one, some other key points can be taken into account to protect yourself, your colleagues or your employees:
- Try out different tools. Choose those that do not give numb fingers when using them for a short amount of time
- Always check that tools are serviced and well maintained
- Use the right tool for the right job. Trigger time is essential here, choose a stronger, more efficient tool that can do the job in a shorter amount of time rather than a lighter one
- Limit time per work shift with strong vibrations uptake. With applications giving strong vibrations, the operator can reach a potentially harming vibration dose within minutes. For reference, with an application that gives 20 m/s² of vibration to the operator’s hands, the exposure corresponding to the action value, (the value where the employer needs to take actions to limit vibrations), is reached after only 8 minutes
- Hold the tool loosely, do not squeeze the handle when not necessary
- Keep hands warm and try to avoid direct contact with freezing or very cold handles. Store the tool correctly so that your colleague will also be comfortable. If possible, do not leave tools outside overnight
- Take regular breaks. Avoid long sequences of high vibrations and try to do other jobs in between.