Division: General equation - 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)

The propulsion noise emission includes all contributions from engine, exhaust, gears, air intake, etc. The propulsion noise sound power level in the frequency band i for a vehicle of class m is defined as:

L_{WP,i,m} = A_{P,i,m} + B_{P,i,m} \times \frac{(v_{m} - v_{ref})}{v_{ref}} + {ΔL}_{WP,i,m}

(2.2.11)

The coefficients A_P,i,m and B_P,i,m are given in octave bands for each vehicle category and for a reference speed v_ref = 70 km/h.

ΔL_WP,i,m corresponds to the sum of the correction coefficients to be applied to the propulsion noise emission for specific driving conditions or regional conditions deviating from the reference conditions:

ΔL_WP,i,m = ΔL_WP,road,i,m + ΔL_WP,grad,i,m + ΔL_WP,acc,i,m

(2.2.12)

ΔL_WP,road,i,m accounts for the effect of the road surface on the propulsion noise via absorption. The calculation shall be performed according to Chapter 2.2.6.

ΔL_WP,acc,i,m and ΔL_WP,grad,i,m account for the effect of road gradients and of vehicle acceleration and deceleration at intersections. They shall be calculated according to Chapters 2.2.4 and 2.2.5 respectively.

Division General equation