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
1,516
Accredited labs
17
Countries
Showing 476–500 of 1,516 labs
Fibre Clear Consulting
Active
M002based on HSG 248
(HSG 248) – 2021
(PCM) based on HSG 248
FlexSpect
Active
#EN ISO 5164:14
# EN 116-97
#ISO 12185
NEN 4400-2
# ISO 13736
+ 3 more
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
flexiblen Akkreditierungsbereich.
Beschleunigung * 10 m/s
Beschleunigungsaufnehmer
Beschleunigungsaufnehmer 10 m/s
digital (DTI)
+ 3 more
Foundation Medicine
Active
(somatische genetische
ACVR1B, AKT1, AKT2, AKT3, ALOX12B, AMER1
GATA3, GATA4, GATA6, GID4, GNA11,GNA13,
CHEK2, CHIC2, CHN1, CIC, CIITA
IRF8, IRS2, ITK, JAK1, JAK2, JAK3, JARID
+ 3 more
Fourstage Environmental
Active
(HSG 248) – 2021
(PCM) based on HSG 248
DOC/002 based on HSG 248
DIN EN ISO 10304-1
DIN EN ISO 11885
DIN EN ISO 15350
DIN EN ISO 15351
DIN EN ISO 17294-2
+ 3 more
- Gleichspannung
Messgeräte 0,33 V bis < 3,3 V
330 V
Quellen
> 0,1 V
+ 3 more
Kraft (WPM) 30 N
Vibration measuring instruments — test m
maschinen nach DIN
Kraft * 10 N
Acoustics — tonality assessment (DIN 456
+ 3 more
DIN ISO 16000-3
DIN EN ISO 12460-3
DIN EN ISO 12460-4
DIN EN ISO 12460-5
100 HV 120
+ 3 more
Tensile testing of metallic materials (I
Vickers hardness test (ISO 6507)
Kurzschlussstrom
Solarmodule 16 mA
Gleichstrom- und Nieder- 10 mV
+ 3 more
HbF
HbA1c
HbA2
HBB/HBD
Anti-HBs
+ 3 more
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 + B Kalibriertechnik
Active
Druck *
Absolutdruck Pabs
1 bar; 3 bar
Negativer und
positiver Ãœberdruck
+ 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
DIN EN 12579
DIN 19698-1
DIN 19698-2
DIN 51750-2
DIN ISO 11277
+ 3 more
No matching labs found.