HAVS monitoring is how employers measure and control the hand-arm vibration workers receive from powered hand tools, and check their health for early signs of hand-arm vibration syndrome (HAVS). In Great Britain it is required under the Control of Vibration at Work Regulations 2005, which set a daily action value of 2.5 m/s² and a limit of 5 m/s².
Key facts
- HAVS is hand-arm vibration syndrome: damage to the nerves, blood vessels, muscles and joints of the hand and arm caused by regular use of vibrating tools.
- Exposure action value (EAV): 2.5 m/s² A(8). Above this, employers must put controls in place to reduce exposure.
- Exposure limit value (ELV): 5 m/s² A(8). No one may be exposed above this on any single day.
- HSE points system: 100 points a day equals the EAV; 400 points a day equals the ELV.
- Health surveillance (regular health checks) is required wherever there is a risk to health.
- HAVS is a different hazard from whole-body vibration, which comes through the seat or feet (for example, from driving plant) and has its own action and limit values.
Why does HAVS matter on the railway?
Much of the work on rail infrastructure uses hand-held powered tools that vibrate: rail saws and disc cutters, rail grinders and drills used in rail welding, breakers and compaction equipment in civils work, and chainsaws and brushcutters in vegetation management. Regular use of these tools without control of trigger time is the main cause of HAVS.
How is vibration exposure measured?
Daily exposure depends on two things: how strongly the tool vibrates (its vibration magnitude, in m/s²) and how long the worker’s hands are on it while it runs (trigger time).
- Estimating from tool data. Employers take the vibration magnitude for each tool, preferably from in-use data rather than the manufacturer’s test figure alone, and combine it with realistic trigger times using HSE’s exposure points system or its vibration exposure calculator.
- Wearable and tool-mounted monitors. Electronic monitors record trigger time automatically and total each worker’s daily points, warning them as they approach the action or limit value. They make records more reliable than paper trigger-time logs.
What must employers do at the action and limit values?
Under the Control of Vibration at Work Regulations 2005, employers must:
- assess the vibration risk to their employees and keep a record of it;
- above the EAV, introduce a programme of controls to eliminate the risk or reduce exposure as far as reasonably practicable, for example by choosing lower-vibration tools, maintaining them, and limiting trigger time through job rotation;
- at the ELV, take immediate action to bring exposure below the limit;
- give workers information and training on the health risks and the controls in place;
- provide health surveillance where there is a risk to health, and keep health records.
What does HAVS health surveillance involve?
Health surveillance means regular, structured health checks for workers exposed to hand-arm vibration, so that early symptoms are picked up before they become disabling. It typically starts with a questionnaire when a worker is first exposed and at regular intervals afterwards. Anyone who reports symptoms is assessed by an occupational health professional, who advises whether the worker can continue using vibrating tools and under what restrictions.
What are the symptoms of HAVS?
HSE lists these early signs:
- tingling and numbness in the fingers, which can disturb sleep;
- loss of strength in the hands, making it harder to pick up or hold heavy objects;
- in cold and wet conditions, fingertips turning white, then red and painful as they recover (vibration white finger, a form of Raynaud’s phenomenon).
With continued exposure the symptoms become more frequent, affect more fingers and can become permanent. Anyone with these symptoms should tell their supervisor and see an occupational health professional or their GP.
Sources
- HSE: Control of Vibration at Work Regulations 2005
- HSE: Employers’ responsibilities – legal duties
- HSE: Vibration risk assessment and the exposure points system
- HSE: Worried about your hands?
- Network Rail: Hand arm vibration syndrome
This content is for general information and does not constitute medical or legal advice. For medical advice, consult a doctor or occupational health professional.
If you have a safety concern or want to discuss anything related to HSQE, contact Debbie Haines, Group Head of Health & Safety, on 0330 113 0004 or safety@rssinfrastructure.com. Alternatively, you can request a callback using our contact form.
