How useful is manufacturer’s data on noise levels in a noise assessment?
Manufacturers of tools and equipment have an obligation to make data available on the expected noise level for their product. The HSE list this as a source of information which employers could use in deciding if there is a noise risk in the workplace, but is it actually any good or useful in a noise assessment?
First step - deciding if you have a noise issue
If you have reason to believe noise levels are approaching 80 dB(A) then there is an obligation to get a noise assessment done, but how do you know noise may be reaching that 80 dB(A) level? That is where manufacturer’s noise level data can come in - if they say their tool or machine is over that 80 dB(A) point then that’s a good sign you need to go full-monty and get a decent noise assessment done to help assess the true risk.
Think of it as licking your finger and holding it up to see how windy it is. It kind of tells you if there is wind or not, but that’s it and that’s where manufacturer’s information on noise levels sit.
Beyond that though?
How useful is the manufacturer’s noise data beyond that once you get into a proper noise assessment? You will be unsurprised to hear ‘not at all’.
The noise level data is gathered by manufacturers under set controlled circumstances but those circumstances are not what happens in the real world and those real world changes can make a huge difference to the noise levels. For example:
When a tool is new it is working exactly as designed but over time wear and tear can quite dramatically increase the noise level. Something as simple as a wearing bearing or an air leak on a compressed air line can significantly change the noise.
When manufacturers generate their noise level data the tool is assessed in isolation and that is usually very unrealistic for actual use. The noise in an area is likely to be that tool, plus all the other machines or tools being used in the area at the time.
Position of a machine can make a huge difference. You have the more obvious ones where a machine placed close to a wall may have a higher noise level for the operator than a machine in the middle of the room as noise is coming from the machine to the person but also bouncing off the wall at them as well. There are the less obvious ones as well as noise is weird and can change depending on things like the spacing of machines. Put two machines a couple of metres apart and their noise levels may multiply together and become larger than each individual one. Put those two machines three metres apart and their noise now starts to cancel each other out and the levels are below the noise emitted by each one. Where machines are put can make a huge difference to the noise levels and make manufacturer’s data rather fanciful.
This also is important with hand tools - using a drill in an open space can be a very different noise level to using the same drill in a small room or in a corner.
Ongoing use of a machine may change its noise. For example, a panel be removed for cleaning or maintenance and then replaced, but it is not fasted quite as tightly as it was previously. Now you have the noise from the machine but also a rattle or vibration from the panel which is contributing to it.
In an on-site noise assessment, the job of actually pointing noise meters at things to measure what is going on, manufacturer’s data is not remotely useful. What we are interested in at that point is the noise level in this specific use case, on this specific site, with this specific set of machines, so generic noise levels from a manufacturer don’t add anything useful here.
Summary on manufacturer’s noise level data
Yes, it can be useful in deciding if you may have a noise risk and if you should get a proper full-fat noise assessment done.
But no, it is not much use beyond that and usually doesn’t bear much resemblance to reality. That’s not a fault or failing of the manufacturers, they can’t account for every usage case.
