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
🇫🇷
NF EN ISO 11821
🇮🇹
UNI EN ISO 11821
🇪🇸
UNE EN ISO 11821
🇳🇱
NEN EN ISO 11821
🇩🇪
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
Accredited labs
15
Countries
Showing 401–425 of 1,273 labs
DIN 51757
DIN EN ISO 12185
DIN EN ISO 3405
DIN EN 13016-1
DIN EN 237
+ 3 more
GMA-Werkstoffprüfung
Active
Koordinatenmesstechnik
Lasertracker*
0,5 m
1) In den CMC sind die erweiterten Messu
Bügelmessschrauben* 0 mm
+ 3 more
GMC-I Service
Active
- Gleichspannung
Messgeräte > 0,22 V
> 2,2 V
> 11 V
> 22 V
+ 3 more
GPR Gesundheits- und Pflegezentrum Rüsselsheim gemeinnützige GmbH Institut für Laboratoriumsmedizin
Active
Erythrozytenzahl
Hämatokrit
Leucozytendifferenzierung
Leucozytenzahl
MCV
+ 3 more
Erythrozytenzahl
Hämatokrit
Leucozytendifferenzierung
Leucozytenzahl
MCV
+ 3 more
Charpy impact test (ISO 148-1)
Salt spray / neutral salt fog test (ISO
Radiated emissions (CISPR 32)
Innen- und Tiefenmaße
Wägewert/
+ 3 more
GRAVICAL
Active
Innen- und Tiefenmaße
Konventioneller
Charpy impact test (ISO 148-1)
Salt spray / neutral salt fog test (ISO
Radiated emissions (CISPR 32)
+ 1 more
GTM Testing and Metrology
Active
Vickers hardness test (ISO 6507)
Kraft
Kraftaufnehmer und
Sound power — survey method (ISO 3746)
0,2 MN
+ 3 more
9,8 L ≤ V ≤ 10,2 L (25 L/h ≤ Q ≤ 500 L/h
98 L ≤ V ≤ 104 L (250 L/h ≤ Q ≤ 5000 L/h
970 L ≤ V ≤ 1005 L (2500 L/h ≤ Q ≤ 20000
1305 L ≤ V ≤ 1350 L (5000 L/h ≤ Q ≤ 8000
2660 L ≤ V ≤ 2700 L (5000 L/h ≤ Q ≤ 1000
DIN 30655-1
DIN 30655-2
DIN 3590-1
DIN 3590-2
DIN 30652-2
+ 3 more
Anti-Müller-Hormon
Androstendion
CA 125
Cortisol
DHEA-S
+ 3 more
Azoospermie (AZF-Mikrodeletionen)
Fragiles X-Syndrom (FMR1)
Chorea Huntington (HTT)
Spinocerebelläre Ataxie Typ1
(ATXN1); Typ 2 (ATXN2); Typ 3
+ 3 more
Gerico Lab Srl
Active
ETSI EN 319 412
ETSI EN 319 401
ETSI EN 319 411-2
ETSI EN 319 411-1
Gerinnungszentrum Rhein-Ruhr
Active
Thrombozytenaggregation
Epinephrin-Ristocetin) nach
Verschlusszeitbestimmung
Kollagen / ADP, PFA-Kollagen
Epinephrin, PFA-P2Y)
+ 3 more
Gesellschaft für Materialforschung und Prüfungsanstalt für das Bauwesen Leipzig mbH - MFPA Leipzig
Active
ISO 1920-4
DIN EN 480-11
DIN EN 12350-1
DIN EN 12350-3
DIN EN 12350-6
+ 3 more
Aktivator ADP / Epinephrin
Thrombozytenfunktionstest
Basophile Leukozyten, absolut
Basophile Leukozyten
Eosinophile Leukozyten
+ 3 more
Gigahertz Optik
Active
spektrale
Mikrofonempfindlichkeit
Photodioden
1 µA/W
Bestrahlungsstärke
+ 3 more
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))
ASTM D3835-16
ASTM D6204-19a
ASTM D6601-19
ISO 11443
ASTM D1238-13
+ 3 more
No matching labs found.