Guidance · Reviewed August 2026
What HAVS is, the exposure action and limit values, why trigger time matters more than shift length, and the one control that does not work.
The short answer
The Control of Vibration at Work Regulations 2005 require employers to assess and control exposure to vibration. For hand-arm vibration the daily exposure action value is 2.5 m/s² A(8) and the limit value is 5 m/s² A(8). The damage — hand-arm vibration syndrome, or HAVS — is permanent, and it builds silently over years.
Two Types of Vibration
Hand-arm vibration (HAV)
Transmitted from hand-held power tools and hand-guided equipment into the hands and arms. Breakers, grinders, sanders, chainsaws, needle scalers, impact wrenches, hammer drills, strimmers, floor saws.
Regular, frequent exposure causes hand-arm vibration syndrome (HAVS) and can cause carpal tunnel syndrome. Both are permanent.
Whole-body vibration (WBV)
Transmitted through the seat or feet of people driving or riding on vehicles and machines over rough ground. Dumpers, excavators, forklifts, tractors, quarry vehicles, some HGVs.
Associated with back pain and lower back injury, particularly where posture is poor or the seat is unsuitable.
What HAVS Actually Does
HAVS affects the blood vessels, nerves, muscles and joints of the hand and arm. It develops gradually, which is why it is so often missed until it is established — and once nerve damage has occurred it does not reverse.
- Vascular symptoms — fingers blanching white in the cold, then red and painful on rewarming. Often called vibration white finger, and usually the first sign anyone notices.
- Sensory symptoms — tingling, numbness, loss of sensation and reduced dexterity. Difficulty picking up small objects, doing up buttons, feeling what is in a pocket.
- Musculoskeletal symptoms — reduced grip strength, pain in the hands, wrists and arms.
- Carpal tunnel syndrome — compression of the median nerve, causing pain, numbness and weakness.
The effect on life outside work is what people underestimate. Losing fine grip and cold sensitivity affects driving, cooking, holding a phone and sleeping, not just the job that caused it.
Exposure Action and Limit Values
The Regulations set two thresholds for daily exposure, both normalised to an eight-hour reference period and written A(8).
| Exposure action value (EAV) | Exposure limit value (ELV) | |
|---|---|---|
| Hand-arm | 2.5 m/s² A(8) | 5 m/s² A(8) |
| Whole-body | 0.5 m/s² A(8) | 1.15 m/s² A(8) |
| What it means | Assess and control the risk, and put health surveillance in place. | Must not be exceeded. Stop, change the tool, the method or the trigger time. |
Manage to the action value, not the limit
The recurring mistake is treating the ELV as the target and the EAV as a formality. The law reads the other way round. Everything that matters — controls, health surveillance, record-keeping — hangs off the lower number.
Trigger Time, Not Shift Length
The number that matters is trigger time — how long the tool is actually running in the hand — not how long someone was on site. Clock time wildly overstates the safe use available, and estimating from it is the commonest way exposure calculations go wrong.
How fast the action value arrives depends entirely on the tool’s vibration magnitude. HSE’s rough guide: a hammer-action tool such as a breaker or demolition hammer is likely to reach the action value after about 15 minutes of trigger time and the limit value after about an hour. Non-hammer tools such as grinders reach the action value after around an hour and the limit value after about four.
If a breaker is running for most of a shift, that day is almost certainly over the limit — whatever the timesheet says.
HSE expresses the same thing as an exposure points system, which most people find easier to work with on site. The action value equals 100 points and the limit value 400 points. Points scale simply with time — double the trigger time, double the points — and, crucially, points from different tools add together. Someone using a breaker and a grinder in the same day accumulates both, which is why single-tool calculations understate real exposure.
Points per hour work out at roughly twice the square of the vibration magnitude, so a 6 m/s² tool generates about 71 points an hour and reaches the action value in under 90 minutes.
Buying beats rationing
Exposure points scale with the square of the vibration magnitude, so a modest reduction in the tool cuts exposure sharply. Swapping a high-vibration tool for a vibration-reduced equivalent can cut the points to a fraction for the same trigger time — usually far more effective than trying to manage minutes on site.
Controlling the Risk
🚫
Eliminate or substitute
Can the task be done without a vibrating tool at all? Hydraulic splitting instead of breaking, remote or mechanised methods, or work brought to a fixed machine rather than a hand-held one.
🔧
Better tools, kept sharp
Buy or hire low-vibration equipment and check the manufacturer’s figures — bearing in mind those are quoted for new tools under test conditions and carry a stated uncertainty. Blunt blades, worn bits and poorly maintained tools vibrate more and take longer, so maintenance is a vibration control rather than just a reliability one.
⏱️
Limit trigger time
Rotate people through high-vibration tasks, plan the sequence so nobody spends a full shift on a breaker, and build in breaks. Useful, but weaker than changing the tool.
🧤
Keep hands warm and dry
Cold makes symptoms worse and may accelerate the damage. Warm gloves, heated grips and somewhere to warm up all help — but see the warning below on what gloves cannot do.
The one control that does not work
Anti-vibration gloves cannot be relied upon. HSE’s position is unambiguous: gloves marketed as anti-vibration are not particularly effective at reducing the frequency-weighted vibration associated with HAVS risk, and at some frequencies they can increase it.
They can be legitimately sold as PPE and may carry a UKCA or CE mark, which makes the assumption an easy one to fall into. They do keep hands warm — genuinely useful — and they protect against cuts. But a glove must never be used to justify a lower calculated exposure.
Unlike noise or dust, there is no effective PPE for vibration. That is exactly why the controls above have to work.
What Employers Must Do
| Duty | In practice |
|---|---|
| Assess exposure | Identify who is exposed and estimate daily exposure from tool magnitude and trigger time. This sits alongside your general risk assessment. |
| Eliminate or reduce | Remove the exposure where reasonably practicable, and reduce what remains to as low a level as is reasonably practicable. |
| Never exceed the ELV | Employees must not be exposed above the limit value. If a calculation says otherwise, the work changes. |
| Health surveillance | Required for anyone regularly exposed at or above the action value, and for anyone already diagnosed with HAVS even where exposure is below it. |
| Inform and train | Users need to know the risk, the symptoms and how to report them early — see health and safety training. |
| Maintain equipment | Vibrating tools are work equipment, so PUWER duties apply alongside these Regulations. |
Health Surveillance
This is the duty most often skipped, and the one that matters most. HAVS gives no warning at the point of damage — by the time someone reports symptoms, the harm is usually established and permanent. Surveillance exists to catch it before that.
It typically runs as a tiered system: a baseline questionnaire before exposure begins, annual screening questionnaires, and referral to an occupational health professional where anything is flagged. A questionnaire that never escalates is not health surveillance — it is a form.
HAVS is RIDDOR reportable
Hand-arm vibration syndrome is a reportable occupational disease under RIDDOR, as is carpal tunnel syndrome where the work involves regular use of percussive or vibrating hand-held power tools. The trigger is a written diagnosis from a doctor.
Worth understanding what that means in practice: HSE investigates HAVS cases reported under RIDDOR, and most vibration prosecutions begin with a RIDDOR report rather than with an inspection. The report is usually the moment the risk becomes visible to the regulator.
Work out your exposure
The free HAVS exposure calculator works out the daily A(8) value from the tools your team actually uses and the trigger time on each, and shows how quickly each tool reaches the action and limit values on its own. No account needed. It sits on envicourse.com, our course marketplace, and opens in a new tab.
Frequently Asked Questions
What does HAVS stand for?
Hand-arm vibration syndrome — permanent damage to the blood vessels, nerves, muscles and joints of the hand and arm caused by regular, frequent exposure to vibration from hand-held power tools. Vibration white finger is one part of it.
What are the exposure limits?
For hand-arm vibration, an exposure action value of 2.5 m/s² A(8) and an exposure limit value of 5 m/s² A(8). For whole-body vibration, 0.5 and 1.15 m/s² A(8). At the action value you must control exposure and provide health surveillance; the limit value must not be exceeded.
Do anti-vibration gloves reduce exposure?
No, not reliably. HSE advises that gloves marketed as anti-vibration cannot be relied upon to protect against vibration — they are not particularly effective at the frequencies that cause HAVS, and can increase vibration at some frequencies. They are worth providing to keep hands warm, since cold makes symptoms worse, but they must never be used to justify a lower calculated exposure or to avoid a control further up the hierarchy.
Is HAVS reportable under RIDDOR?
Yes. HAVS is a reportable occupational disease, as is carpal tunnel syndrome where the work involves regular use of percussive or vibrating hand-held power tools. The trigger is a written diagnosis from a doctor. HSE investigates HAVS cases reported under RIDDOR, and most vibration prosecutions begin with a report rather than an inspection.
How long can someone safely use a vibrating tool?
It depends entirely on the tool’s vibration magnitude, not the length of the shift. A hammer-action tool such as a breaker typically reaches the action value after around 15 minutes of trigger time and the limit value after about an hour. Grinders and other non-hammer tools take roughly an hour and four hours respectively. Always work from measured trigger time — clock time badly overstates the safe use available.
Is HAVS reversible?
No. Once nerve and vascular damage has occurred it is permanent. Removing or reducing exposure early can stop it progressing, which is exactly why health surveillance and early reporting matter — the point of catching it at stage one is that stage two never arrives.
Who needs health surveillance?
Anyone regularly exposed at or above the exposure action value, anyone exposed occasionally above it where the risk assessment identifies a risk to health, and anyone already diagnosed with HAVS — even where their current exposure is below the action value.
Related Guidance
RIDDOR →
Musculoskeletal disorders →
Risk assessment →
Noise at work →
All guidance topics →
General guidance only, reviewed against HSE guidance INDG175 and L140, and the Control of Vibration at Work Regulations 2005, in August 2026. Envico is an independent training intermediary and is not affiliated with the HSE.