What is whole-body vibration (WBV)?
Whole-body vibration enters through the seat or feet — typical of trucks, loaders, forklifts, and mobile plant. Long exposure is linked to back injury and fatigue. EU Directive 2002/44/EC and UK Control of Vibration at Work Regulations set daily A(8) action and limit values.
- EAV — 0.5 m/s²
- ELV — 1.15 m/s²
Enter vibration magnitude and exposure time below (add rows for several machines). Pair with the HAV calculator for hand-transmitted vibration.
Whole-Body Vibration (WBV) Calculator
WBV · Whole-body vibration A(8)
Daily exposure for seat/feet vibration. Compare with EAV 0.5 m/s² and ELV 1.15 m/s² (EU/UK).
Formula: A(8) = a × √(t ÷ 8) · multi-source: √(Σ a² × t ÷ 8)
- Use vibration at the operator seat or feet for the real task.
- WBV limits differ from HAV (2.5 / 5.0 m/s²).
- Improve seats, tyres, speed, and route quality before cutting hours alone.
For one source: A(8) = a × √(t ÷ 8). For several: A(8) = √(Σ aᵢ² × tᵢ ÷ 8).
Frequently asked questions
Where do I get the vibration value?
Manufacturer declared seat values, in-use measurements, or industry databases — match the operating condition (surface, speed, load).
Is WBV the same as HAV?
No. WBV is through the body via seat/feet; HAV is through the hands from powered tools. Limits differ (0.5 / 1.15 vs 2.5 / 5.0 m/s²).
Does seat suspension change the number?
Yes. Enter the vibration at the operator interface after the seat, or use declared values that already include the seat when that is what your assessment method requires.
What if A(8) exceeds the ELV?
Reduce exposure that day — shorter time, better seats, smoother routes, lower speeds, job rotation — and review the risk assessment.
