Hearing loss is the injury nobody notices until it is permanent. Add the noisy tasks and see the eight-hour exposure.
| Sound | dB(A) | Safe for about |
|---|---|---|
| Normal conversation | 60 | All day |
| Busy site, general | 80 | All day |
| The standard | 85 | 8 hours |
| Circular saw, grinder | 95 | 48 minutes |
| Jackhammer, concrete saw | 100 | 15 minutes |
| Demolition hammer close up | 105 | 5 minutes |
| Explosive tool, nail gun | 110+ | Under 2 minutes |
Every 3 dB is double the sound energy, so it halves the time you can be exposed. That is why 88 dB for four hours is the same dose as 85 dB for eight.
Noise is a hazard you have to manage, not just hand out earplugs for. The SWMS libraries cover the noisy trades - concrete cutting, demolition, jackhammering, grinding - and the Registers Library has the PPE issue register that proves you supplied it.
The Australian exposure standard for noise is LAeq,8h of 85 dB(A), and a peak of 140 dB(C) which must never be exceeded at all. This tool does the eight-hour arithmetic from levels you enter - it is not a measurement, and typed estimates are not a noise assessment. Where exposure is near or over the standard, get it measured properly and arrange audiometric testing. General information, not legal advice.
Obras Onsite Pty Ltd · ABN 54 698 828 821
The tools above are free and yours to use. When you need the paperwork behind them reviewed by someone who has run sites, Obras HSE Services is a live consulting business in south-east Queensland.