• Sound reduction index

Performances are characterised by the sound reduction index R_A,tr which measures the capacity to block out noise from roads (traffic). It is better when the glass components are thicker and/or of different thicknesses. This index is measured according to EN 140 standard.
 

• Acoustic performance classes

These classes AR1 to AR6 include sound reduction indices from 25 dB to 38 dB to deal with road noise.