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 126–150 of 1,273 labs
BP Europa SE Aral Forschung
Active
DIN EN ISO 6246
DIN 53160-1
DIN EN ISO 22854
(LBLS) (OMIM 611105) (c.228-
DIN EN 13016-1
+ 3 more
BS EN ISO 10140-2:2021
BS EN ISO 10140-3:2021
BS EN ISO 717-2:2020
ISO 7171
BS EN ISO140-3:1995 (withdrawn)
+ 3 more
BSI á Íslandi ehf
Active
Nominal value
TEMPERATURE
See Notes 1 to 3
TORQUE
Case Manager: BC4
+ 1 more
UNE-EN 13284-2
UNE-EN 15259
UNE-EN 16911-2
UNE-EN 13284-1
UNE EN 1911
+ 3 more
Babcock Marine [Rosyth]
Active
(HSG 248) – 2021
14B based on HSG 248
DIN EN 12021
14A based on HSG 248
(PCM) based on HSG 248
+ 2 more
Balis Micro
Active
AM09 based on BS ISO 21527-1:
DIN EN ISO 21528-2
DIN EN ISO 4833-2
BS ISO 15214:1998
0.95) based on BS ISO 21527-2:2008
Bareiss Prüfgerätebau
Active
Sound intensity — scanning method (ISO 9
Messgeräte für die
Härteskale Shore A*
Analoge Anzeige
Railway freight wagon brake system requi
+ 3 more
Bax Engineering
Active
Temperaturanzeigegeräte
–100 °C bis
- Direktanzeigende Thermometer
- Thermopaare, Thermoelemente
verwendete Abkürzungen:
Salmonella spp.
Antikörper)
Treponema pallidum (Lues)
Thrombozytäre Antikörper
dysenteriae), Vibrio cholerae
+ 3 more
Echinococcus granulosus
Echinococcus multilocularis
Paragonimus uterobilateralis
Ascaris lumbricoides (IgG)
Brucella spp. (IgG, IgM)
+ 3 more
Hämoglobin
Differentialblutbild
Erythrozyten
Großes Blutbild
Kleines Blutbild
+ 3 more
Okkultes Blut
Großes Blutbild
Kleines Blutbild
Retikulozyten
Thrombozyten
+ 3 more
2C-B
2C-I
3-Hydroxy-Bromazepam
5-Hydroxyindolessigsäure
6-Acetylcodein
+ 3 more
Zelldifferenzierung
Erythrozyten
Großes Blutbild
Hämoglobin
Kleines Blutbild
+ 3 more
Hämoglobin (immunologisch)
CA 125
CA 15-3
CA 19-9
CA 72-4
+ 3 more
Hämoglobin
Natriumchlorid
Kalium
Natrium
Eiweißelektrophorese: Albumin, Alpha-1-G
+ 3 more
10-OH-Carbazepin
11-Deoxycortisol
17-OH-Progesteron
21-Deoxycortisol
25-OH Vitamin D2
+ 3 more
Thrombozytenfunktion
5-Hydroxyindolessigsäure
Adrenalin
Amiodaron, Desmethylamiodaron
Carbohydrate-deficient
+ 3 more
Bioscientia MVZ Labor Saar
Active
Lamotrigin
Metanephrine, Normetanephrine
Erythrozyten
Aripiprazol
Lymphozyten
+ 3 more
Birmingham City Council
Active
(HSG 248) – 2021 )
(PCM) based on HSG 248)
(PCM) based on HSG 248
staining based on HSG 248
(HSG 264, 2012)
Bizerba SE &
Active
IEC 61000-4-2: 2008
IEC 61000-4-3: 2006
IEC 61000-4-4: 2012
IEC 61000-4-5: 2005
IEC 61000-4-6: 2013
+ 3 more
staining based on HSG 248
(HSG 248) – 2021
(PCM) based on HSG 248
(HSG 264:2012)
Bridgend Asbestos Services
Active
(HSG 248) – 2021
P10.2 based on HSG 248
(PCM) based on HSG 248
No matching labs found.