H.A.V.S – Hand arm vibration syndrome (HAVS) is caused by occupational exposure to vibrating hand tools. These could be sanders, chainsaws, drills and jackhammers etc. This can lead to employees developing an advanced stage of hand-arm vibration syndrome (HAVS) associated with disabling loss of hand function. It is possible that your employees who are exposed to vibration may have mild symptoms of HAVS. If they are not aware that they have the disease, Occupational health surveillance can help them to recognise that the first symptoms of HAVS have started to develop.
Symptoms:
Employees whose hands are regularly exposed to vibration may suffer from damage to the tissues of the hands and arms, which causes the symptoms collectively known as HAVS. These symptoms include:
Numbness and tingling in the fingers, and a reduced sense of touch and temperature, due to damage to nerves in the hand. This damage can make it difficult to feel, and to work with, small objects.
Periodic attacks during which the blood circulation in the fingers is impaired and parts of the fingers become white (blanched). This is sometimes known as ‘vibration white finger’, ‘dead finger’ or ‘dead hand’. During these attacks the fingers feel numb. As blood circulation returns to normal, either by itself or after rewarming the fingers, they are typically throbbing, red and painful. Although vibration causes the condition, it does not bring on the attacks. The main trigger for these symptoms is exposure to the cold, e.g. being outdoors early on a winter’s morning, or by localised or general body cooling in otherwise warm environments. Rarely, in very advanced cases, blood circulation may be permanently affected.
joint pain and stiffness in the hand and arm. Grip strength can be reduced due to nerve and muscle damage.
Symptoms continued:
An individual employee with HAVS may not experience the complete range of symptoms, e.g. there may be nerve damage symptoms without there being blood circulation problems and vice versa. The symptoms of HAVS are usually progressive as exposure to vibration continues, e.g. the effects on blood circulation are seen initially in the tips of the affected fingers, with changes spreading up the finger. The thumb may also be affected.
Carpal tunnel syndrome:
Carpal tunnel syndrome, a disorder of the hand and arm, which may involve tingling, numbness, pain and weakness in parts of the hand, can also be caused by exposure to vibration. Also see the link for Raynaud’s disease where the hands are affected by temperature.
Living with HAVs:
Employees suffering from HAVS can have trouble in carrying out tasks in the workplace involving fine work or manipulative work and are less able to work in cold conditions. The disease may have an impact on earnings and on social and family life. Everyday tasks may become difficult, e.g. fastening small buttons on clothes. Attacks of ‘white finger’ will take place not only at work, but during other activities, especially if people get cold, such as when washing the car or watching outdoor sports. The damage to the hands may be irreversible.
Its a one way street:
After symptoms first appear, generally the longer an employee is exposed to vibration, the worse the symptoms become, although the rate of deterioration will vary from person to person. How much symptoms may improve when people are no longer exposed to vibration is not well understood, but it is thought that nerve damage does not recover after exposure stops. The effects on blood circulation may improve after reducing or stopping vibration exposure in people below about 45 years old and when the disease has not yet reached the advanced stage associated with disability. Any improvement will be slow, taking several years and smoking may also slow down recovery.
When is health surveillance required?
Health surveillance should be provided for vibration-exposed employees who:
• are likely to be regularly exposed above the action value of 2.5 m/s2 A (8); 2
• are likely to be exposed occasionally above the action value and where the risk assessment identifies that the frequency and severity of exposure may pose a risk to health; or
• have a diagnosis of HAVS (even when exposed below the action value).
If you are self-employed there is no legal requirement for you to have health surveillance for HAVS. However, it is important for your well-being, and for your ability to remain in work, that you identify any early signs of HAVS and take appropriate action. It is therefore recommended that you follow this guidance if you think you are at risk from vibration.
