Division 2.2.5: Effect of the acceleration and deceleration of vehicles - 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)

Before and after crossings with traffic lights and roundabouts a correction shall be applied for the effect of acceleration and deceleration as described below.

The correction terms for rolling noise, ΔL_WR,acc,m,k , and for propulsion noise, ΔL_WP,acc,m,k , are linear functions of the distance x (in m) of the point source to the nearest intersection of the respective source line with another source line. They are attributed to all octave bands equally:

${ΔL}_{WR,acc,m,k} = C_{R,m,k} \times Max (1 - \frac{\|x\|}{100};0)$	(2.2.17)
${ΔL}_{WP,acc,m,k} = C_{P,m,k} \times Max (1 - \frac{\|x\|}{100};0)$	(2.2.18)

The coefficients C_R,m,k and C_P,m,k depend on the kind of junction k (k = 1 for a crossing with traffic lights; k = 2 for a roundabout) and are given for each vehicle category. The correction includes the effect of change in speed when approaching or moving away from a crossing or a roundabout.

Note that at a distance |x| ≥ 100 m, ΔL_WR,acc,m,k = ΔL_WP,acc,m,k = 0.

Division 2.2.5 Effect of the acceleration and deceleration of vehicles