What Is Hand-Arm Vibration Syndrome (HAVS)?

Hand-arm vibration is the transfer of vibration from a tool or workplace to a worker’s hands or arms.
The level of hand-arm vibration is determined by measuring the acceleration of the tool or object grasped by the worker.

Hand-Arm Vibration Syndrome (HAVS) is a disease that involves circulatory disturbances, sensory and motor disturbances and musculoskeletal disturbances.
While it has been known since the beginning of the 20th century that vibration effects the hands and arms, it was not until 1983 that scientists agreed on a definition of HAVS that includes the circulatory, nervous and musculoskeletal systems.

Symptoms or Signs of HAVS

• Bluish discoloration (cyanosis) of the skin of fingers and hands.
• Whitening (blanching) of fingertips after cold or damp exposure. Also know as Raynaud's Phenomenon.
• Numbness, with or without tingling happens, before, during or after blanching.
• Attacks, more common in winter, but eventually may occur year round. Palms of the hands are rarely affected.
• Reduced sense of touch and pain perception, sometimes permanent.
• Decreased grip strength, and inability to sustain muscle power.

What Can Happen If Symptoms Are Ignored?

• The tingling and numbness in the fingers, and loss of grip strength can cause problems with using objects, and they may slip from the hands.
• There can be serious interference with work, home activities and hobbies.
• Some activities (particularly in the cold) may have to be avoided to prevent the vessel spasms, which cause pain.
• Studies show that, depending on the conditions of exposure:
• 6 to 100 percent of workers can suffer from HAVS after using vibrating power tools
• On average, about 46 percent get HAVS symptoms

Causes

Daily exposure to hand and arm vibration by workers who use vibrating tools powered by compressed air, gasoline and electricity can cause physical damage to the hands and arms.

Examples of tools include:

• Powered/Jack Hammers
• Chisels and Grinders
• Chain / Power Saws
• Riviters and Drills
• Sanders, Sharpeners and Shapers
• Compactors

Some of the trades/industries in which workers are at risk include:

• Construction
• Forestry
• Mining and Quarry
• Ship and Rail Yard
• Manufacturing and Foundry
• Agriculture

Treatment

Restore immediate circulation to blanched fingers, by:

• Putting hands in warm water
• Swinging your arms
• Doing other exercises that increase blood flow (e.g. jumping jacks)

Wear warm, dry clothes and maintain core body temperature (e.g. wear a vest).

There is no treatment/therapy at present for neurological symptoms other than removal from vibration exposure, but improved circulation may help with nerve recovery.
See your doctor for specific screening tests and assessment.

Stop Smoking: Some cardiac drugs (e.g. beta-blockers) contribute to the problem by increasing vaso-spasms, whereas others (Felodipine or Nifedipine) will improve peripheral circulation.
Check with your physician.

Since vibrating tools usually create loud noise, be sure to get your hearing checked frequently as well. Since hearing damage is progressive, often removal from exposure to vibration/noise source is the best way to prevent further damage.

Prevention

Employers must establish a health and safety program to remove or reduce workplace hazards.

A Joint Health and Safety Committee (JHSC) is responsible to identify risks and hazards and make recommendations to the employer on programs, measures and procedures to reduce or remove these hazards.

The following are recommendations the JHSC can make to their employer:

• Request management to provide safe hand tools, and regular maintenance of the tools
• Measure vibration exposure
• Get technical advice
• Get medical advice
• Warn exposed workers
• Provide full training to exposed workers
• Review exposure times and provide adequate rest breaks away from vibrating tools (eg. Reduce exposure hours, decrease the number of days exposed to vibrating tool by job rotation)
• Have a policy on removal/reduction of vibration from the workplace

Avoiding Hand Arm Vibration Syndrome (HAVS) in the Workplace

The Joint Health and Safety Committee should establish a prevention and training program for all workers at risk and include the following information:

• How to recognize symptoms like finger tingling, numbness and finger blanching.
• The critical need to report any symptoms immediately.
• The possible serious health effects of overtime, shiftwork and double shifts.
• The role of proper tool maintenance (poorly dressed grinding wheels or worn bearings can have higher vibration levels than new or well maintained tools).
• The need for immediate reporting of poorly functioning tools.
• The Ergonomic aspects of tool use and the relation to correct body posture.
• The need to avoid unnecessary vibration exposure, by proper tool handling.
• The need to wear gloves, particularly anti-vibration (a/v) ones.
• The need for whole body warmth and especially warm dry hands.
• The correct design and fit, and use of personal protective equipment.
• The use of work/rest schedule, job rotation and exercises which can maintain blood circulation.
• An understanding of vibration exposure levels from tools used. Information on appropriate WSIB claims reporting.