Noise, vibrations and hearing protection in metalwork
Still hearing well in twenty years
Hearing loss comes gradually. You don't notice it from day to day but after many years in a noisy workshop the damage has occurred — and it cannot be repaired because the damaged sensory cells in the ear do not grow back. In the metal workshop noise comes from hammer blows against stake and anvil from grinding and polishing machines and from pneumatic tools. Therefore protection against noise is one of the most important ongoing occupational health considerations in the trade.
§The Labour Authority's action values
The rules on noise are based on fixed thresholds for the daily noise exposure measured in dB(A). At the lower action value of 80 dB(A), the employer must make hearing protection available and inform about the risk. At the upper action value of 85 dB(A), hearing protection must be used, and measures must be taken to reduce noise. Daily noise exposure must not exceed the limit value of 85 dB(A), and there is also a limit for sharp impulse sounds (peak value).
| Level | Meaning | Requirement |
|---|---|---|
| 80 dB(A) | Lower action value | Hearing protection provided information |
| 85 dB(A) | Upper action value / limit | Hearing protection MUST be used noise must be reduced |
| Spidsværdi | Loud impulse sounds | Special limit for short, loud bangs |
§Vibrations from hand tools
Pneumatic chisels, grinders and pneumatic engraving handpieces transfer vibrations to the hand and arm. Prolonged exposure can cause hand-arm vibration syndrome with reduced sensation, strength and blood flow in the fingers (so-called 'white fingers'). Vibration load is reduced by choosing vibration-damped tools, keeping tools maintained and sharp, taking breaks and avoiding gripping harder than necessary.
How to take care of your hearing and hands
- 01Use hearing protection from 80 dB(A), and always when grinding and hammering
- 02Choose pre-moulded earplugs or cup hearing protection that fits
- 03Dampen noisy items and shield loud machines.
- 04Choose vibration-damped and well-maintained pneumatic tools
- 05Keep hands warm and take breaks during vibrating work
- 06Get your hearing checked regularly if you work in noise
Signals in case of too much noise
- 01You must raise your voice to talk to a colleague a meter away.
- 02You have ringing in your ears (tinnitus) after the work day
- 03Sounds seem muffled in the hours after work
- 04You are tired and unmotivated by the constant noise
“Hearing is the only one you have — and it cannot be replaced.”