Calculation of Road Traffic Noise – Online CRTN Calculator

Mini Cat Noise

Online CRTN Calculator

This free online calculator is based on the Calculation of Road Traffic Noise (CRTN) standard and can be used to predict the LA10 at a receiver location. This CRTN calculator is designed for a simple scenario containing one road segment in order to calculate the Basic Noise Level from the traffic flow, traffic speed and percentage of heavy goods vehicles (HGV’s) as well as the propagation distance from source to receiver. The calculator includes the standard correction for:

  • Gradient
  • Road surface type
  • Ground cover correction
  • Obstruction due to objects such as buildings and barriers
  • Site layout correction

What is the CRTN Standard?

The CRTN memorandum describes the standard UK procedure for the measurement and calculation of road traffic noise. According to the memorandum, the procedures are necessary to enable entitlement under the Noise Insulation Regulations to be determined but they also provide guidance appropriate to the calculation of traffic noise for more general applications e.g. environmental appraisal of road schemes, highway design and land use planning.

The memorandum is divided in three sections including:

  • Section I: a general method for the calculation of traffic noise
  • Section II: additional procedures for applying Section I to specific situations (e.g. road junctions)
  • Section III: the procedure and requirements for road traffic noise measurements

This CRTN calculator is based on Section I of the CRTN standard.

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Please note that this or any other calculators on the tools room are for information only. WKC Group has endeavoured to ensure that the information presented here is accurate and that the calculations are correct, but will not accept responsibility for any consequential damages, faults or human errors that may arise from the use of formulas, inventories and values.