BS 4142:2014+A1:2019

1.1 This British Standard describes methods for rating and assessing sound of an industrial and/or commercial nature, which includes: sound from industrial and manufacturing processes; sound from fixed installations which comprise mechanical and electrical plant and equipment; sound from the loading and unloading of goods and materials at industrial and/or commercial premises; and sound from mobile plant and vehicles that is an intrinsic part of the overall sound emanating from premises or processes, such as that from fork-lift trucks, or that from train or ship movements on or around an industrial and/or commercial site. The methods described in this British Standard use outdoor sound levels to assess the likely effects of sound on people who might be inside or outside a dwelling or premises used for residential purposes upon which sound is incident. 1.2 This standard is applicable to the determination of the following levels at outdoor locations: rating levels for sources of sound of an industrial and/or commercial nature; and ambient, background and residual sound levels, for the purposes of: investigating complaints; assessing sound from existing, proposed, new, modified or additional source(s) of sound of an industrial and/or commercial nature; and assessing sound at proposed new dwellings or premises used for residential purposes. 1.3 The determination of noise amounting to a nuisance is beyond the scope of this British Standard. Sound of an industrial and/or commercial nature does not include sound from the passage of vehicles on public roads and railway systems. The standard is not intended to be applied to the rating and assessment of sound from: recreational activities, including all forms of motorsport; music and other entertainment; shooting grounds; construction and demolition; domestic animals; people; public address systems for speech; and other sources falling within the scopes of other standards or guidance. The methodology set out in Clauses 7, 8, and 9 of this standard is not intended to be used to assess the extent of the impact at indoor locations. Internal sound levels can be taken into account as outlined in Clause 11. The standard is not intended to be applied to the assessment of indoor sound levels. The standard is not applicable to the assessment of low frequency noise. NOTE Information on the assessment of low frequency noise is given in NANR45 [1, 2].