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
🇬🇧
BS EN ISO 11821
🇫🇷
NF EN ISO 11821
🇮🇹
UNI EN ISO 11821
🇪🇸
UNE EN ISO 11821
🇳🇱
NEN EN ISO 11821
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DIN EN ISO 3095
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BS EN ISO 3095
🇫🇷
NF EN ISO 3095
🇮🇹
UNI EN ISO 3095
🇪🇸
UNE EN ISO 3095
🇳🇱
NEN EN ISO 3095
1,273
Accredited labs
15
Countries
Showing 126–150 of 299 labs
Eurofins Food Testing UK
Active
Method 15.2 based on BS EN ISO
ISO 15213-2
Method 9.8 based on BS EN BS EN
Method 5.11 based on BS EN ISO
Method 4.3 based on BS EN ISO
+ 3 more
Eurofins Food Testing UK
Active
ISO 6579-1
ISO 4832
EUMM 3.03 based on BS EN
EUMM 3.07 based on BS EN ISO
BS ISO 21528-2:2017
+ 3 more
Eurofins Food Testing UK
Active
ISO 712
ISO 4833-1
on BS EN ISO 1736:2008
ISO 21528-2
BS ISO 4832:2006
+ 3 more
Fibre Clear Consulting
Active
M002based on HSG 248
(HSG 248) – 2021
(PCM) based on HSG 248
Fluke Precision Measurement
Active
Frequenc 220 mV range
FREQUENCY
10 Hz to 100 kHz
difference from 10 % to 100 % of the sta
6105A control 0° to 360°
+ 3 more
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
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))
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)
+ 3 more
No matching labs found.