Hand-Arm Vibration Syndrome (HAVS)
Introduction
Hand-Arm Vibration Syndrome (HAVS) is basically an umbrella term that refers to the group of vascular, neurological and musculoskeletal health effects associated with the use of vibrating tools.
In laymen terms, it implies the transfer of vibration from a tool or work piece to a worker’s hands and arms.
The rate of acceleration of the tool or object grasped by the worker determines the level of hand-arm vibration that occurs. Also known as Dead Man’s Hand, HAVS is a potentially hazardous disorder and can lead to painful and disabling disorders of the blood vessels, nerves, joints and muscles of the hands and arms.
Incidence and Prevalence
The HAVS is a widespread occupational hazard, affecting over 1 million UK workers who are exposed to vibration over the Health and Safety executive action limit of 2.8m/s2.
Reports reveal that HAVS is the most common disease reported under the Reporting of Injuries, diseases and dangerous occurrence, regulations (RIDDOR).
Another set of research studies show that around five million workers are exposed to hand-arm vibration in the workplace. However, what is most hazardous is that almost two million of these workers are exposed to levels of vibration where there are clear risks of developing a disease.
Symptoms and Causes
The key signs and symptoms of the HAVS might differ in context with the different patients. However, here we’ve listed some of the most common symptoms associated with the disease.
Cyanosis (bluish discoloration) of the skin of fingers and hands Blanching or whitening of fingertips after cold or damp exposure Numbness, that might be accompanied by tingling, occurring either before or after blanching Marked decrease in grip strength and inability to sustain muscle power Reduction in sense of touch and pain perception, which might become permanent over time
The Hand-Arm Vibration Syndrome is primarily caused by the use of vibrating hand-held tools, for instance, pneumatic jackhammers, drills, gas powered chain saws and electrical tools such as grinders.
Such tools involve vibration which is transferred form the tool to the hands and arms of the person holding the tool.
Preventive Measures
There are a series of preventive measures that can be adopted at the workplace to avoid the occurrence or recurrence of the Hand-Arm Vibration Syndrome.
Here we list the main amongst them:
Use alternative work methods Replace old and worn-out equipment Conduct regular maintenance on the equipment Employees should have proper clothing to keep warm and dry, as it helps to improve blood supply to the hands Modifying tools by adding anti-vibration handles or plastic vibration reducing materials on the handles Reducing the number of tasks where the vibrating tools need to be used Reducing exposure times by encouraging job sharing or job rotation
Treatment Methods
The treatment modalities for Hand-Arm Vibration Syndrome involve a combination of medication, physical therapy and self-care measures.
In addition to the above listed preventive measures, certain medications also help in this condition. These include calcium-channel blockers, pentoxyphylline for improving the flexibility of red blood cells and drugs in order to reduce the platelet deposition.