ISO 11820:2019

In-Situ Sound Attenuation Measurement of Silencers

ISO 11820 specifies the in-situ measurement method for determining the acoustic attenuation performance of silencers installed in railway ventilation ducts, brake systems, and exhaust lines. This test is critical for validating noise control equipment on operating trains and stationary installations where laboratory testing is impractical. Railway manufacturers, maintenance operators, and acoustic engineers use these measurements to verify compliance with noise regulations and to optimize silencer design. Accreditation ensures that attenuation claims are reliable and that performance targets for noise reduction are consistently achieved in real-world applications.

What it measures

  • Sound pressure level reduction across silencer (dB)
  • Attenuation performance by frequency band
  • Insertion loss of silencer in situ
  • Acoustic performance under operating conditions
  • Noise transmission loss through silencer element
🇧🇪 NBN EN ISO 11821 🇩🇪 DIN EN ISO 11821 🇬🇧 BS EN ISO 11821 🇫🇷 NF EN ISO 11821 🇮🇹 UNI EN ISO 11821 🇪🇸 UNE EN ISO 11821 🇳🇱 NEN EN ISO 11821 🇧🇪 NBN EN ISO 3095 🇩🇪 DIN EN ISO 3095 🇬🇧 BS EN ISO 3095 🇫🇷 NF EN ISO 3095 🇮🇹 UNI EN ISO 3095
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Sound intensity — scanning method (ISO 9 Hand-arm vibration — measurement (ISO 53 Railway testing reference handbook part messeinrichtungen von Pendelschlagwerke und + 3 more
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DAkkS D-K-18164-01-01 Partenstein, DE
Railway braking — adhesion under braking Koordinatenmessgeräte geräte mit einem DEA Hexagon Metrology Polyworks, Software von Metrologic, Software von + 3 more
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8tree GmbH 8tree Calibration Lab

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(Härteskalen HV0,01 8tree Scanner / 0 mm bis 100 mm Laterale Größe von Tiefenmaß/ -unterstand + 2 more
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DIN EN ISO 2719 DIN EN 12879 DIN EN 12880 DIN EN ISO 19458 DIN EN 932-1 + 3 more
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ABB AG Kalibrierlaboratorium für Druck, Durchfluss und Temperatur

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DAkkS D-K-12115-01-00 Minden, DE
Railway overhead lines — pantograph head - Direktanzeigende Thermometer - Thermopaare, Thermoelemente abs positiver Überdruck + 3 more
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ABPI Aalener Baustoffprüfinstitut

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DAkkS D-PL-19436-01-01 Aalen, DE
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DAkkS D-PL-22802-01-01 Eching am Ammersee, DE
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DAkkS D-K-21076-01-01 Haldenwang, DE
Railway brake — anti-slide device (UIC 5 Railway brake — magnetic track brakes (U Railway brakes — conditions for homologa Railway brakes — electropneumatic brakes Railway braking — urban guided transport + 3 more
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- Wechselstromstärke Quellen Widerstände / Messgeräte > 100 V + 3 more
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DAkkS D-PL-14191-01-01 Frankfurt (Oder), DE
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DAkkS D-PL-11133-01-01 Bochum, DE
Sound power level determination — genera Sound power — engineering methods for sm Sound power — in-situ using reference so Sound intensity — scanning method (ISO 9 Occupational noise exposure measurement + 3 more
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DAkkS D-PL-11316-01-00 Großheide, DE
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ALBO-tec Technologiezentrum für Analytik und Bodenmechanik

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ALS Analytik Labor Schirmacher

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DAkkS D-PL-14594-01-01 Hamburg, DE
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ALS Germany

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DAkkS D-PL-14162-01-03 Altenberge, DE
> 660 HABP2-Gen (c.1601G>A) rs7080536 ASTM E 648 DIN EN 61646 ISO 11948-1 + 3 more
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ALSTOM Transportation Germany GmbH Prüfstelle für Schienenfahrzeuge

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DAkkS D-PL-11003-01-00 Hennigsdorf, DE
Sound power level determination — genera Sound power — engineering methods for sm Sound power — in-situ using reference so Sound intensity — scanning method (ISO 9 Occupational noise exposure measurement + 3 more
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ALSTOM Transportation Germany GmbH Prüfstelle für eisenbahntypische Prüfungen an Schienenfahrzeugen

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DAkkS D-PL-11003-07-00 Görlitz, DE
Railway braking — thermal analysis (EN 1 Railway wheel squeal and curve noise (EN DIN 27201-5 DIN 25043-1 DIN 25043-2 + 3 more
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DAkkS D-K-15060-01-00 Dettingen unter Teck, DE
und Radsatzmerkmale 22 mm 133 mm Antastelementen mit Messschieber für 0 mm Bügelmessschrauben* 0 mm + 3 more
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Industries

Railway rolling stock manufacturing Train maintenance and depot operations Acoustic engineering and noise control HVAC and ventilation system design Brake system suppliers and integrators

Related Standards

  • ISO 11821 Acoustics — In-situ measurement of sound insulation of windows and façades
  • EN ISO 3095 Acoustics — Measurement of noise emitted by railbound vehicles
  • ISO 7235 Acoustics — Laboratory measurement of sound absorption coefficient of materials in impedance tubes

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