A BS 4142 assessment is a means of ‘rating’ noise impact based on a comparison between the noise from the source under assessment (the specific noise) and the background noise which would exist in the absence of that source. The specific noise is ‘corrected’ for ‘acoustic features’ by adding a decibel penalty for tonal or impulsive content and for any other features which are readily distinctive against the background acoustic environment. The corrected noise level is referred to as the ‘rating level’ and is intended to reflect people’s general reaction to noise whereby noise with such features is found to be more annoying than featureless noise at the same level. This rating level also includes a similar correction applied where the noise source does not operate continuously.

If you need a BS4142 assessment completed by a suitably qualified person, please do not hesitate to contact us using the contact details listed on this website.

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