BS4142 | Noise Survey | Acoustic Reports | Noise Assessments
BS4142 Noise Assessments
Custom Audio Designs provide BS4142 Noise Surveys for all types of situations. This type of noise survey is usually required by the local planning department when a new noise source is introduced into an existing noise sensitive environment.
What is a BS4142 Noise Survey?
BS4142 is a British Standard that describes the procedures and methods for measuring and assessing noise to determine if it will
cause noise complaints from neighbouring properties. Most local planning departments will ask for a BS4142 noise survey
to be carried out when any noise making activity, or equipment, is going to be introduced close to where people live.
How does BS4142 assess the noise?
BS4142 derives a Rating Level by comparing the Specific LAeqNoise Level against the current background LA90noise level. If the new noise source contains any hums or other tonal components a 5dB penalty is added. If the Rating level exceeds the background noise level by around 10dBA or more this indicates that complaints are likely. A difference of around 5dBA is of marginal significance and a difference of more than 10dBA below the background noise level then this is a positive indication that complaints are unlikely.
How long does a BS4142 Noise Survey Take?
To a degree this can depend on when the noise will be occuring and the specific stipulations from the local authority. If a noisy machine is operating between 23:00 and 07:00 then it would be necessary to measure the background noise levels in the early hours of the morning to obtain a measure of the lowest background noise level in the vicinity. If the noise source is only operating in the daytime then nightime measurements are unlikely to be required. The duration of the survey will also depend on the type of noise and any duration cycle.
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