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
🇩🇪 DIN EN ISO 11821 🇬🇧 BS EN ISO 11821 🇫🇷 NF EN ISO 11821 🇮🇹 UNI EN ISO 11821 🇪🇸 UNE EN ISO 11821 🇳🇱 NEN EN ISO 11821 🇩🇪 DIN EN ISO 3095 🇬🇧 BS EN ISO 3095 🇫🇷 NF EN ISO 3095 🇮🇹 UNI EN ISO 3095 🇪🇸 UNE EN ISO 3095 🇳🇱 NEN EN ISO 3095
1,516 Accredited labs
17 Countries

Showing 476–500 of 799 labs

Partnerschaftspraxis für Laboratoriumsmedizin und Mikrobiologie

Active
DAkkS D-ML-13116-01-01 Hameln, DE
Hämoglobin Selen Lithium Zink Eisen, Kupfer + 3 more
View Profile

Perschmann Calibration

Active
DAkkS D-K-15089-01-01 Braunschweig, DE
Parallelendmaße * 0,5 mm DIN EN ISO 3650:1999 > 100 mm Sonderquerschnitt (rund Parallelendmaße * > 100 mm + 3 more
View Profile

Pharmaserv GmbH Kalibrierlabor

Active
DAkkS D-K-18321-01-00 Marburg, DE
Temperaturmessgrößen Widerstandsnormal thermometer (IPRT) Zeiss Industrielle Temperaturmessgrößen −35 °C + 3 more
View Profile

Polytest Ingenieure

Active
DAkkS D-PL-21123-01-02 Fürth, DE
DIN EN ISO 9934-1 DIN ISO 815-1 DIN ISO 815-2 DIN ISO 4593 DIN EN 50178: 1998 + 3 more
View Profile

Power Diagnostix Systems

Active
DAkkS D-K-15068-01-00 Aachen, DE
Impulsladung Anstiegszeit Impulsdauer Wechselspannung 1 V > 1,1 kV + 3 more
View Profile

Praxis für Labormedizin, med. Thomas Müller

Active
DAkkS D-ML-13079-01-00 Aschaffenburg, DE
Differentialblutbild Erythrozyten Hämatokrit Leukozyten Retikulozyten + 3 more
View Profile

Privatärztliche Gemeinschaft für Diagnostik Köln-Bonn

Active
DAkkS D-ML-19686-01-00 Köln, DE
HbA1c Automatisches Blutbild Leukozyten Normoblasten Retikulozyten + 3 more
View Profile

Privatärztliche Laborgemeinschaft Köln

Active
DAkkS D-ML-22827-01-01 Köln, DE
Calcium Bilirubin gesamt Creatinkinase-Muscle-Brain TPZ nach Quick Immunglobulin A + 3 more
View Profile

ProfEC Ventus

Active
DAkkS D-PL-19142-01-00 Oldenburg, DE
IEC 61400-12 Ed.1 * IEC 61400-12-1 Ed.3 * IEC 61400-12-3 Ed.1 * IEC 61400-12-4 Ed.1 * IEC 61400-12-5 Ed.1 * + 3 more
View Profile

Prüf-, Überwachungs- und Zertifizierungsgemeinschaft der Straßenausstatter e.V. - StrAus-Zert

Active
DAkkS D-PL-17639-01-00 Hagen, DE
DIN 68877-2 DIN EN ISO 2178 DIN EN 16272-1 DIN EN 12899-1 DIN EN 12899-5 + 1 more
View Profile

Prüfstelle für Betonstahl - Gallus Rehm

Active
DAkkS D-PL-18743-01-01 München, DE
ISO 15835-2 UNE-EN 10002-1 BS EN ISO 15630-1:2019 UNE-EN 10080 BS EN ISO 15630-3:2019 + 3 more
View Profile

QS-Grimm

Active
DAkkS D-K-15159-01-01 Gutach Schwarzwaldbahn, DE
Parallelendmaße * 0,5 mm DIN EN ISO 3650:1999 Zylindrische Normale 1 mm Innenzylinder * > 100 mm + 3 more
View Profile

Qopas

Active
DAkkS D-K-12048-01-00 Driedorf, DE
Koordinatenmessgeräte geräte mit einem Chorus, Help-PJM von DEA Hexagon Metrology S.p.A., Turin, I Associates EMS Products, ≤ 1500 mm + 3 more
View Profile

Questmed

Active
DAkkS D-PL-18753-02-00 Kleinmachnow, DE
ISO 22679 ISO 7207-1 ISO 14243-1 ISO 14243-2 ISO 14243-3 + 3 more
View Profile

RIO

Active
DAkkS D-K-17376-01-00 Siegen, DE
Parallelendmaße * 0,5 mm DIN EN ISO 3650:1999 > 100 mm > 500 mm > 550 mm + 3 more
View Profile

RMA Mess- und Regeltechnik

Active
DAkkS D-K-20908-01-00 Rheinau, DE
Durchfluss von Gasen Volumendurchfluss 50 m³/h Railway brakes — brake performance (UIC (Hochdruck Erdgas 5 bis 51 bar) + 1 more
View Profile

ROTA YOKOGAWA

Active
DAkkS D-K-17720-01-00 Wehr, DE
Masse m strömender − Durchfluss von Flüssigkeiten Durchfluss von 1) In den CMC sind die erweiterten Messu Massedurchfluss dm / dt + 3 more
View Profile

Robert Koch-Institut

Active
DAkkS D-ML-13113-01-01 Berlin, DE
Salmonellen Salmonella enterica, Shigellen, Yersinie Shigellen Salmonella sv. Paratyphi Neisseria meningitidis, Listeria + 3 more
View Profile

Rolf Langenscheid GmbH Waagensystemtechnik

Active
DAkkS D-K-21801-01-00 Lüdenscheid, DE
Charpy impact test (ISO 148-1) Salt spray / neutral salt fog test (ISO elektronische Waagen 1) In den CMC sind die erweiterten Messu
View Profile

Ruhr Lab

Active
DAkkS D-PL-21007-01-00 Gelsenkirchen, DE
ISO 13909-2 ISO 13909-3 ISO 13909-5 ISO 13909-7 ISO 13909-8 + 3 more
View Profile

Ruhr Oel GmbH BP Gelsenkirchen

Active
DAkkS D-PL-19612-01-00 Gelsenkirchen, DE
DIN EN ISO 12185 DIN EN ISO 3405 DIN EN 13016-1 DIN EN ISO 20884 DIN EN ISO 20846 + 3 more
View Profile

Ruhr-Universität Bochum Humangenetik RUB

Active
DAkkS D-ML-13425-01-00 Bochum, DE
Spinocerebelläre Ataxien Bindegewebserkrankungen: ACTA2, COL1A1, HD; Chorea Huntington (Huntingtin-Gen) Dentatorubrale-Pallidoluysiane + 3 more
View Profile

S.K.I. Schlegel & Kremer Industrieautomation GmbH Kalibrierlabor

Active
DAkkS D-K-21982-01-00 Mönchengladbach, DE
Durchfluss von 2 m3/h bis 800 rn3/h − Durchfluss von Flüssigkeiten Volumendurchfluss dV/dt von strörnenden + 3 more
View Profile

SBKS

Active
DAkkS D-PL-11303-01-01 St. Wendel, DE
DIN 53394-2 DIN 53176 DIN EN ISO 1172 ASTM D 5576 IEC 60512-11-4 + 3 more
View Profile

SGS Germany

Active
DAkkS D-PL-11020-03-01 Puchheim, DE
IEC 61000-4-2: 2008 IEC 61000-4-3: 2006 IEC 61000-4-4: 2012 IEC 61000-4-5: 2005 IEC 61000-4-6: 2013 + 3 more
View Profile

No matching labs found.

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

Other Test Methods

0 labs selected
Compare