This latest edition of BS 4142 has been prepared under the direction of the Health and Environment Sector Board, and the methods described are for rating and assessing sound from situations including: – 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 forklift trucks, or that from train or ship movements on or around and industrial and/or commercial site.
The BS 4142:2014 standard must be applied for the purposes of: -investigating complains, – assessing sound from proposed, new, modified or additional sources of sound of an industrial and/or commercial nature, and – assessing sound at proposed new dwellings or premises used for residential purposes.
Did you know that with the new BS 4142:2014 – – the Sound Meter and Calibrator used must be Class 1 or Type 1? – measurements must be taken between 1.2m and 1.5m from the ground?
The conditions of the environment where the measurements take place is discussed in the new BS 4142:2014 standard.
Preferred conditions: – Dry, clear, light wind or calm
Conditions to avoid: – High winds cause trees / hedges to ‘rustle’, – Wind > 5 m/s avoided (should be measured with an anemometer) – Rain – impact noise on trees / roofs, higher tyre noise on roads – Temperature Inversion (over long distances) – Electrical Interference (i.e. EMF) – Measured levels shall be considered valid only if they exceed readings on the measuring instrument owing to the above influences by at least 10 dB. – Weather Station Monitoring · Wind Speed & Direction · Temperature & Humidity · Rainfall & Pressure · Visually Note Cloud Cover (% or Oktas: 0-8)
1) Determine LAeq,T with the specific sound 2) Determine LAeq,T without the specific sound 3) Correct item (1) above for residual noise (2) 4) Correct for On-Time 5) Distance correct if not at receiver location 6) Add character correction to obtain rating level (LAr,Tr) 7) Determine background noise (LA90,T) 8) Subtract LA90,T from LAr,Tr 9) Assess the potential for Adverse Impact
Download our free 1 hour BS 4142 training webinar to enable you to handle any commercial noise complaints. Presented by Simon Bull, Managing Director of Castle Group Ltd.
The full standard is available to purchase from the British Standards Institution.