In the United Kingdom a working party of the Noise Advisory Council has considered the proliferation of noise scales and noise indices. It appeared to the working party that if planning policy for noise and new development was to be coherent, then standards of acceptable noise from different sources ought to be consistent. In turn this consistency seemed to require that noise from all sources be measured and rated on a unified scale. Further it was anticipated that the use of a unified scale would greatly facilitate the evaluation of the respective contribution from each source in those situations where the noise arose from a multiplicity of sources and also by standardisation of instrumentation and techniques would lead to economies in the monitoring and control of noise. The working party recommended the adoption of the equivalent sound level, leq, as the unified measure of noise. A supplement to the working group report by the Department of the Environment discusses the administrative problems of applying the unified measure in situations where a different measure has already been applied. One such situation arises in the assessment of traffic noise which at present in the UK is rated on the l10 (18 hours) index 2. (this is the arithmetic average of the hourly l10 levels between 0600 and 2400 hours on a normal working day). This paper reviews some of the evidence on the measurement of traffic noise considered by the working group and some more recent data. The working party reported that the terms 'index', 'scale', and 'unit' occur frequently within the literature, often without distinction, and this is confusing. They adopted the convention that the instantaneous auditory magnitude was specified by a measure of level, that the term "noise scale" would refer to a combination of the physical variables (sound pressure, time, etc) which contribute to people's overall response to noise and that the term "noise index" would be reserved for the numerical description of noise in which other factors (corrections for type of neighbourhood, night-time corrections, etc) were superimposed on the scale numbers describing the physical properties of the noise. The author has tried to follow this convention. /TRRL/

  • Corporate Authors:

    Transport and Road Research Laboratory (TRRL)

    Wokingham, Berkshire  United Kingdom 
  • Authors:
    • HARLAND, D G
  • Publication Date: 1977

Media Info

  • Features: Figures; References;
  • Pagination: 8 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00164234
  • Record Type: Publication
  • Source Agency: Transport and Road Research Laboratory (TRRL)
  • Report/Paper Numbers: TRRL Supp Report 297
  • Files: ITRD, TRIS
  • Created Date: Jun 14 1978 12:00AM