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
1,516
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17
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Showing 526–550 of 1,516 labs
Gerinnungszentrum Rhein-Ruhr
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Thrombozytenaggregation
Epinephrin-Ristocetin) nach
Verschlusszeitbestimmung
Kollagen / ADP, PFA-Kollagen
Epinephrin, PFA-P2Y)
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Gesellschaft für Materialforschung und Prüfungsanstalt für das Bauwesen Leipzig mbH - MFPA Leipzig
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ISO 1920-4
DIN EN 480-11
DIN EN 12350-1
DIN EN 12350-3
DIN EN 12350-6
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Thrombozytenfunktionstest
Basophile Leukozyten, absolut
Basophile Leukozyten
Eosinophile Leukozyten
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Gigahertz Optik
Active
spektrale
Mikrofonempfindlichkeit
Photodioden
1 µA/W
Bestrahlungsstärke
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Glasgow City Council
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(HSG 248) – 2021
staining based on HSG 248
F2011 (BS 696:Part 2:1989)
F0131 (BS 1741:10-1:1989) using
F0008 (BS 696:Part 2:1989) using
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Greengea Srl
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DIN EN ISO 7730
ISO 5667-5
DIN EN ISO 6888-1
DIN 40633-2
DIN EN ISO 18593
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ISO 10195
ISO 17704
BS EN ISO 14362-1
ISO 14184-1
ISO 4045
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Gully Howard Technical
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HSG 227 (2004))
(HSG 264, 2012)
HSG 264 (2012) and Appx. 3 of
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ASTM D3835-16
ASTM D6204-19a
ASTM D6601-19
ISO 11443
ASTM D1238-13
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ISO 3105
ASTM D 7042
ISO 2909
ASTM D 5293
ISO 3104
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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
Handbetätigte
20 N·m
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induzierte Thrombozytopenie, Test)
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> 200 V
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HFB Engineering
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DIN EN ISO 10666
DIN 53438-3
rs738409
DIN EN 1382
DIN EN 1383
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Gleichspannung a)
/ Messgeräte
> 600 kV
Messsysteme, Teiler
> 5 kV
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IEC 61000-4-2: 2008
VDE 0847-4-2
IEC 61000-4-4: 2012
VDE 0847-4-4
IEC 61000-4-5: 2005
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HLK Stuttgart
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DIN EN 442-2
DIN EN 16430-1
DIN EN 16430-2
DIN EN 16430-3
DIN 4703-3
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