Scope
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
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NF EN ISO 11821
🇮🇹
UNI EN ISO 11821
🇪🇸
UNE EN ISO 11821
🇳🇱
NEN EN ISO 11821
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DIN EN ISO 3095
🇬🇧
BS EN ISO 3095
🇫🇷
NF EN ISO 3095
🇮🇹
UNI EN ISO 3095
🇪🇸
UNE EN ISO 3095
🇳🇱
NEN EN ISO 3095
1,273
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15
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Showing 1,176–1,200 of 1,273 labs
angeborener Chromosomensatz
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Fragiles X-Syndrom: FMR1
Spinocerebellare Ataxie (SCA)
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Thrombozytenaggregation
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6-Methyl-Mercaptopurinnukleotide
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Thrombozytenaggregation
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Verschlußzeit Kollagen/ADP
Verschlußzeit Kollagen/Adrenalin
6-Methyl-Mercaptopurinnukleotide
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angeborener Chromosomensatz
Molybdän-Cofaktor Defizienz
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Fragiles X-Syndrom: FMR1
Spinocerebellare Ataxie (SCA)
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alpha-Aminobuttersäure
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angeborener Chromosomensatz
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H19, KCNQ1OT1
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5 a 18 mm/s (Valor pico) (frecuencias en
5 a 12 mm/s (RMS) (frecuencias entre 8 H
VWR International
Active
TEMPERATURE
parameters and ranges)
indicators or recorders
WEIGHING INSTRUMENTS
Vectoflow
Active
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
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Retikulozyten
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Vintec Laboratories
Active
(HSG 248) – 2021
(PCM) based on HSG 248
P052 based on HSG 248
Vistec Electron Beam
Active
− Permanentes Laboratorium
Positionen und Abstände
gleichgerichteter Kanten
positionen von Strukturen
(Hartschichtmasken)
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