Division: General principles - Commission Directive (EU) 2015/996 of 19 May 2015 establishing common noise assessment methods according to Directive 2002/49/EC of the European Parliament and of the Council (Text with EEA relevance)

For road surfaces with acoustic properties different from those of the reference surface, a spectral correction term for both rolling noise and propulsion noise shall be applied.

The road surface correction term for the rolling noise emission is given by:

{ΔL}_{WR,road,i,m} = α_{i,m} + β_{m} \times \lg (\frac{v_{m}}{v_{ref}})

(2.2.19)

where

α_i,m is the spectral correction in dB at reference speed v_ref for category m (1, 2 or 3) and spectral band i.
β_m is the speed effect on the rolling noise reduction for category m (1, 2 or 3) and is identical for all frequency bands.

The road surface correction term for the propulsion noise emission is given by:

ΔL_WP,road,i,m = min{α_i,m ;0}

(2.2.20)

Absorbing surfaces decrease the propulsion noise, while non-absorbing surfaces do not increase it.

Division General principles