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
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DIN EN ISO 11821
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BS EN ISO 11821
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NF EN ISO 11821
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UNI EN ISO 11821
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UNE EN ISO 11821
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NEN EN ISO 11821
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DIN EN ISO 3095
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BS EN ISO 3095
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NF EN ISO 3095
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UNI EN ISO 3095
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UNE EN ISO 3095
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NEN EN ISO 3095
1,516
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VWR International
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TEMPERATURE
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indicators or recorders
WEIGHING INSTRUMENTS
Vectoflow
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am Standort Vectoflow Windtunnel A, Frie
Strömungsgeschwindigkeit
von Gasen 15 m/s bis
> 38 m/s
DIN EN ISO 1463
DIN EN ISO 3497
DIN EN 14518
DIN EN ISO 18452
IEC 62642-3
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Blutbild, kleines (Erythrozyten, Leukozy
Erythrozyten
Leukozyten
Retikulozyten
Thrombozyten
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Vintec Laboratories
Active
(HSG 248) – 2021
(PCM) based on HSG 248
P052 based on HSG 248
Vistec Electron Beam
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Positionen und Abstände
gleichgerichteter Kanten
positionen von Strukturen
(Hartschichtmasken)
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WENZEL Metrology
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Koordinatenmessgeräte
von <7000 mm
under-Edge, UK
INCA3D, Software von
Inspect 3D, Cholet, F
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WIKA Alexander Wiegand SE &
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Positiver und −1 bar bis −0,03 bar
Positiver und negativer
(ein- oder mehrgängige
> −0,03 bar bis
> 0,15 bar bis
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WIN Messmittel und Service
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− Parallelendmaße
− Längenmessmittel
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− Formabweichung
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WSP UK
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(PCM) based on HSG 248
SSA based on HSG 248
WTLAB
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IEC 62109-1
IEC 61400-21-1
IEC 62109-2
DIN EN 60598-2-4
DIN EN 60068-2-30
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Waagen-Dienst Kirste
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Charpy impact test (ISO 148-1)
Salt spray / neutral salt fog test (ISO
elektronische Waagen
verwendete Abkürzungen:
1) In den CMC sind die erweiterten Messu
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Waagen-Jöhnk
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Charpy impact test (ISO 148-1)
Salt spray / neutral salt fog test (ISO
Radiated emissions (CISPR 32)
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Waagen-Kissling
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Charpy impact test (ISO 148-1)
Salt spray / neutral salt fog test (ISO
Radiated emissions (CISPR 32)
verwendete Abkürzungen:
Waagenfachhandel Hilke
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Charpy impact test (ISO 148-1)
Salt spray / neutral salt fog test (ISO
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Wagner Umweltgeologie
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DIN EN ISO 5667-1 (A 4) *
DIN 38402-A 12 *
DIN 38402-A 13 *
DIN EN ISO 5667-3 (A 21) *
DIN 38402-A 30 *
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DIN EN 2561
DIN EN ISO 14126
DIN EN ISO 14125
DIN EN 2563
DIN 53504
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Steuerungssoftware Messvolumen mit einer
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GmbH, Gießen, D
Werth Messtechnik ≤ 600 mm
Werth Messtechnik ≤ 150 mm
Wessex Power Technology
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TEMPERATURE
controllers, and recorders)
RELATIVE HUMIDITY
DIN IEC 60060-1
VDE 0432- 1
IEC 60270
VDE 0434
DIN EN 61243-1
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