Understanding EN 1793-1 Acoustic Performance Classification

Scope of EN 1793 and single-number ratings

EN 1793 has three parts. Part 1 defines laboratory test methods for the intrinsic airborne sound insulation of noise barriers. Part 2 defines in-situ performance verification using a reference sound source. Part 5 defines intrinsic absorption performance. The standard is referenced in CE marking Technical Construction Files (TCF) for noise barrier & acoustic barrier products. The headline single-number rating for airborne sound insulation is DL in dB. Frequency bands are typically reported in 1/3-octave bands from 100 Hz to 5 kHz. Yukings provides both frequency-band and broadband values on every acoustic test report.

DL: the insertion loss metric

DL or insertion loss is the reduction in sound pressure level at a receiver when a noise barrier is placed between source and receiver, compared with the bare-path scenario. DL is path-dependent because it depends on barrier height, source-receiver geometry, terrain profile and edge diffraction. It is, however, the single most important specification for a noise barrier project because it determines whether regulatory targets at receivers are met. The EN 1793-2 classification letter B with numeric suffix is a product classification. It does not by itself guarantee a project-level insertion loss because project geometry must be modelled separately. Always ask for a site-level insertion loss simulation.

DLR: reflection and ground plane absorption

A less discussed but technically important parameter is DLR or reflection performance. A panel that absorbs sound on the source side reduces reflection back toward the carriageway and improves barrier performance by attenuating the sound field in the source half-plane. This is particularly important in narrow trenches, tunnel portals and cuttings where reflected sound is significant. EN 1793-1 absorption classification ranks panels from A1 (low absorption) through A4 (high absorption). Yukings metal-louvered absorption panels typically achieve class A2 to A3 depending on internal mineral wool density and cavity design.

How to read an EN 1793 test report

A full EN 1793 test report includes laboratory identification, panel sample description, test frequency bands and the derived single-number ratings. When evaluating reports from noise barrier suppliers focus on four checks. First, confirm the report is from an ILAC-accredited laboratory and is less than 5 years old. Second, verify that the panel tested matches the panel specified in your project including panel depth, outer sheet mass, perforation pattern and mineral wool type. Third, compare the DL single-number rating with the target insertion loss from your acoustic model including a 3-5 dB margin. Fourth, verify that the report contains the full frequency-band spectrum from 100 Hz to 5 kHz.

Pitfalls when comparing panels between suppliers

Three pitfalls are common when comparing noise barrier panels. First, comparing DL values between panels of different depth without correcting for wind load and structural cost. A 140 mm panel will always outperform an 80 mm panel but costs more and imposes larger wind loads. Second, comparing a broadband DL from one supplier with a single-frequency measurement from another - always request the full frequency-band spectrum. Third, using EN 1793 DL as the sole specification without modelling the project geometry.