1 Scope
This document specifies the laboratory method for measuring the sound absorption performance
of railway noise barriers and related devices acting on airborne sound propagation in reverberant conditions.
It covers the assessment of the intrinsic sound absorption performance of devices
that can reasonably be assembled inside the testing facility described in EN ISO 354.
This method is not intended for the determination of the intrinsic characteristics
of sound absorption of noise barriers and related devices acting on airborne sound propagation to be installed on railways
in non-reverberant conditions.
The test method in EN ISO 354 referred to in this document excludes devices that act as weakly damped resonators.
However, some devices will depart significantly from these requirements and in these
cases, the interpretation of the results may be not straightforward.