What is hand-arm vibration?
Hand-arm vibration (HAV) is vibration that is transmitted into the worker’s hands and arms through the palms and fingers. Vibration transmission occurs when someone is working with or holding:
- Handheld power tools (e.g., sanders, jackhammers, rock drills).
- Hand-guided equipment (e.g., lawnmowers, snow blowers, plate compactors).
- Materials being processed by machines (e.g., using a pedestal grinder).
What are the health effects of HAV?
The most common outcome of exposure to HAV is what is called “hand-arm vibration syndrome,” or HAVS. HAVS is a collective term for a multitude of symptoms affecting the vascular neurosensory and musculoskeletal systems of the hand and arm. Other conditions that may result from exposure to HAV are carpal tunnel syndrome, bone cysts, and osteoarthritis.
The three components of HAVS are:
- Vascular: reduced blood flow in the fingers and hands and the development of Raynaud’s Phenomenon or vibration white finger.
- Neurosensory: reduced dexterity, pain, tingling, numbness, and loss of sense of touch.
- Musculoskeletal: muscle, joint or bone pain, reduced strength, and symptoms of arthritis.
Generally, the development of HAVS is gradual and increases in severity over time. It may take a few months to several years for the symptoms of HAVS to become clinically noticeable. HAVS is preventable, but once the damage has occurred, the health effects are permanent.
Who is at risk of exposure to HAV?
Workers who regularly use power tools, hand-guided equipment, or handle vibrating materials are at risk. Below are some industries where workers may be at risk and the activities that may expose them to the risk:
- Construction: jackhammering, coring, drilling, sanders, etc.
- Forestry: chainsaws, brush cutters, stump grinders, etc.
- Manufacturing: grinders, riveters, drills, sanders, etc.
- Landscaping: lawnmowers, line trimmers, sheers, etc.
- Automotive repair: pneumatic drills, grinders, sanders, etc.
Factors that affect the risk
There are many factors that affect the risk of developing adverse health effects from exposure to HAV:
- Exposure level (m/s2): the more vibration a tool generates, the higher the risk.
- Exposure frequency and duration: the more frequently and the longer that vibrating tools are used, the higher the risk.
- Tool characteristics: older tools, tools that are not properly maintained, and/or using the wrong tool for the job generally results in increased vibration levels.
- Work surface: work surfaces (e.g., wood, metal, concrete) influence the vibration level. Typically, working on harder and rougher surfaces increases the vibration level generated.
- Workplace layout: using tools in tight or constrained spaces, or working overhead, may result in workers using tools while in awkward postures or holding the tools with increased grip strength — both of which increase the risk of HAV.
- Environmental: exposure to the cold leads to reduced blood circulation, which compounds the effect of vibration exposure. This can occur when tools are used in cold, damp conditions. The risk is also heightened when using tools with metallic handles.
- Personal health condition: having pre-existing medical conditions, previous injuries, and/or smoking may result in increased risk of developing adverse health outcomes.
Read more
|
