EN 1793-5:2016

European foreword
Introduction
1 Scope
2 Normative references
3 Terms and definitions
4 Symbols and abbreviations
5 Sound reflection index measurements
Annex A (informative) - Measurement uncertainty
Annex B (informative) - Template of test report on sound
        reflection of road noise barriers
Annex C (informative) - Near field to far field relationship
Bibliography

This European Standard describes a test method for measuring a quantity representative of the intrinsic characteristics of sound reflection from road noise reducing devices: the reflection index.The test method is intended for the following applications:- determination of the intrinsic characteristics of sound reflection of noise reducing devices to be installed along roads, to be measured either on typical installations alongside roads or on a relevant sample section;- determination of the in situ intrinsic characteristics of sound reflection of noise reducing devices in actual use;- comparison of design specifications with actual performance data after the completion of the construction work;- verification of the long-term performance of noise reducing devices (with a repeated application of the method).The test method is not intended for the following applications:- determination of the intrinsic characteristics of sound reflection of noise reducing devices to be installed in reverberant conditions, e.g. inside tunnels or deep trenches.Results are expressed as a function of frequency, in one-third octave bands between 100 Hz and 5 kHz. If it is not possible to get valid measurements results over the whole frequency range indicated, the results shall be given in a restricted frequency range and the reasons of the restriction(s) shall be clearly reported.