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
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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
🇮🇹
UNI EN ISO 3095
🇪🇸
UNE EN ISO 3095
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NEN EN ISO 3095
1,273
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HAZET-WERK Hermann Zerver
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Tensile testing of metallic materials (I
Vickers hardness test (ISO 6507)
Drehmoment 2 N·m
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20 N·m
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HCG, ß-HCG
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Spannungsmessgeräte
> 20 V
> 200 V
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DIN EN ISO 10666
DIN 53438-3
rs738409
DIN EN 1382
DIN EN 1383
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Messsysteme, Teiler
> 5 kV
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IEC 61000-6-1
IEC 61000-6-2: 2005
VDE 0839-6-1
VDE 0839-6-2
power port EN 61000-4-29
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HLK Stuttgart
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DIN EN 442-2
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DIN 4703-3
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M003 based on HSG 248
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M002based on HSG 248
HSG 227 (2004))
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HYDAC Systems & Services
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Gleichspannung 0 µV
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HaBu Hauck Prüftechnik
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Härte *) 20 HRA
Härtevergleichsplatten 20 HRB
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40 HRD
60 HRF
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Hampshire Scientific Service
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BS EN 13480 Parts 1 to 8 - Metallic
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BS EN ISO 15614 and ASME IX
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automatische Zelldifferenzierung
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(HSG 264, 2012)
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Absolutdruck p
abs
> 41 bar
Negativer und
positiver Überdruck
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Heywood Williams Components
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DIN EN 1026
DIN EN 12046-2
BS 6375-1:2015 + A1:2016 and the
DIN EN 1027
DIN EN 1629
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Hohenstein Laboratories
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DIN 53160
DIN 54034
DIN 54056
DIN EN 20105-A02
DIN EN 20105-N01
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Taupunkttemperatur
thermometer, -80 °C bis
Railway braking — urban guided transport
> -35 °C bis
Temperatur- −35 °C bis
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Hottinger Brüel & Kjaer
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Freifeld-Leerlauf- 20 Hz
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