A practical comparison of occupational noise standards

The use of digital signal processing in noise measurement instruments has dramatically increased the measurement capabilities of even the simplest sound level meters and noise dosimeters. There are often a wide range of frequency and time weightings available as well as a selection of thresholds, exchange rates, criterion times and criterion levels. In many modern instruments, the results of a measurement are presented to the user automatically and this can often result in confusion as to the correct value or parameter to report, especially when the metrics appear to be very similar. In the case of occupational noise exposure, this can result in the under or over reporting of values when there is a need to provide data under a range of different or multiple standards. This paper describes a review and a comparison of a range of different occupational noise standards using real-world noise sources. The review demonstrates the differences in how the same physical noise exposure is reported under these different regulations, how often similar standards can produce significantly different outcomes and suggests ways in which users can be informed about the nature of the noise measurement data that they are presented with.