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
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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
Accredited labs
17
Countries
Showing 151–175 of 345 labs
Fourstage Environmental
Active
(HSG 248) – 2021
(PCM) based on HSG 248
DOC/002 based on HSG 248
Fugro GB
Active
BS 1377: Part 2: 1990
BS 1377-3:2018 + A1:2021
ASTM D4186-12: 2020
ASTM D5334-22
ASTM D2216-19
+ 3 more
Furness Controls
Active
FLOW
Gas pressure (absolute)
Gas pressure (gauge)
DC CURRENT
TEMPERATURE
+ 3 more
G&L Consultancy
Active
(HSG 248) – 2021
M4 based on HSG 248
(PCM) based on HSG 248
M3 based on HSG 248
(HSG 264, 2012)
+ 1 more
G&M Procter
Active
based on ISO 11133:2014+Amd
dependent) based on BS EN
based on BS EN 12322:1999
G.B.N.S. Partnership
Active
(HSG 248) – 2021
(PCM) based on HSG 248
PRO02 based on HSG 248
Gaspack Services
Active
BS EN ISO 18119:2018+A1:2021
BS EN 14876:2007/Internal proceduresDiss
BS EN ISO 10460:2018
ISO 23088:2020
Glasgow City Council
Active
(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
+ 3 more
Gully Howard Technical
Active
HSG 227 (2004))
(HSG 264, 2012)
HSG 264 (2012) and Appx. 3 of
Appendix 5 of HSG 227 (2004))
HORIBA MIRA
Active
IEC/CISPR 25
DIN EN 55025: 2018
ISO 7637-2
ISO 11451-1
IEC/CISPR 12
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HSL Compliance
Active
(HSG 248) – 2021
M003 based on HSG 248
(PCM) based on HSG 248
M002based on HSG 248
HSG 227 (2004))
+ 2 more
Hampshire Scientific Service
Active
(HSG 248) - 2021
ASB/SOP/OM8 based on HSG 248
ASB/SOP/OM6 based on HSG 248
DIN EN 12697-11
on BS 4401:Part 3:1970(1986)
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Hartford Steam Boiler UK
Active
BS 2790 - Specification for the design a
BS 1113 - Specification for the design a
BS EN 13480 Parts 1 to 8 - Metallic
EN 13445 – Parts 1 to 10 Unfired pressur
BS EN ISO 15614 and ASME IX
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(HSG 264, 2012)
and Appx. 3 of HSG 227 (2004))
Executive guides HSG 264 (2012)
Heywood Williams Components
Active
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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I2 Analytical
Active
staining based on HSG 248.
(HSG 248) – 2021
(PCM) based on HSG 248
A007B based on BS EN15051-2:2013 +1:2016
DIN EN 12457-3
+ 3 more
ITS Testing Services (UK)
Active
BS EN ISO 1833-1:2020
And the following parts of ISO 1833
ISO 1833-4:2017/EU Reg. method 2ISO 1833
ISO 1833-3: 2019
ISO 1833-6: 2019
+ 3 more
ASTM D 5443
ASTM D2892 (modified)
ASTM D2503
ASTM D4052 (modified)
ASTM D2887 (modified)
+ 3 more
No matching labs found.