Scope
IEC 60268-16:2011
Speech Transmission Index Measurement
This test method provides an objective measure of speech intelligibility in acoustic environments using the Speech Transmission Index (STI) method. STI quantifies how well speech is transmitted through an acoustic space, accounting for noise, reverberation, and frequency distortion. The measurement is critical for evaluating communication effectiveness in public address systems, conference rooms, classrooms, and other speech-critical environments. Venues with high standards for speech clarity use this method to verify system performance and acoustic suitability. ISO 17025 accreditation ensures reliable assessment of speech intelligibility compliance with design standards.
What it measures
- Speech Transmission Index (STI) value (0-1 scale)
- Modulation transfer function across frequency bands
- Speech intelligibility rating and quality assessment
- Impact of noise and reverberation on speech clarity
- Communication effectiveness and auditory conditions
🇩🇪
DIN EN ISO 3382-2
🇬🇧
BS EN ISO 3382-2
🇫🇷
NF EN ISO 3382-2
🇮🇹
UNI EN ISO 3382-2
🇪🇸
UNE EN ISO 3382-2
🇳🇱
NEN EN ISO 3382-2
🇩🇪
DIN EN ISO 1996-2
🇬🇧
BS EN ISO 1996-2
🇫🇷
NF EN ISO 1996-2
🇮🇹
UNI EN ISO 1996-2
🇪🇸
UNE EN ISO 1996-2
🇳🇱
NEN EN ISO 1996-2
1,670
Accredited labs
18
Countries
Showing 1–25 of 1,670 labs
1A CAL
Active
- Gleichspannung
Josephson-Josephson
Multimeter
Quellen > 0,2 V
Spannungsnormale
+ 3 more
20/30 Labs
Active
cartridges, based on HTM 2030
9.201 to 9.212 and BS EN ISO
35 °C/3 days based on HTM 2030
section 9.201 to 9.212, BS EN
ISO 15883-1:2009 6.4.2.3 and
+ 3 more
3-Rath Kalibrier+Prüftechnik
Active
Sound intensity — scanning method (ISO 9
Härteprüfmaschinen
Knoop- und
70 HR15N
42 HR30N
+ 3 more
3D Service
Active
Münchingen, D
CAM 2, Software von
Holos, Software von Carl
Metrologic, Software
von Metrologic Group ≤ 9090 mm
+ 3 more
4-RAIL Services
Active
(HSG 248) – 2021
E203 based on HSG 248
(PCM) based on HSG 248
E200 based on HSG 248
E201 based ISO 14966:2019 using
+ 1 more
8tree Scanner / 0 mm bis 100 mm
Laterale Größe von
Tiefenmaß/
-unterstand
(Härteskalen HV0,01
DIN ISO 1817
ISO 4045
DIN EN ISO 20347
ISO 17697
ISO 4643
+ 3 more
A.Q.C. SRL
Active
ASTM E 415 21
DIN EN 10164
DIN EN ISO 3651-1
ASTM A 262-15
ASTM G48-11
+ 3 more
Kraft 0,5 N
Zug- und Druckkraft
Vibration measuring instruments — requir
Sound power — in-situ using reference so
20 kN
+ 3 more
-95 kPa ≤ P < -1 kPa -1 kPa ≤ P < -100 P
5 kPa ≤ P < 80 kPa 80 kPa ≤ P ≤ 120 kPa
0 MPa ≤ P ≤ 2 MPa 2 MPa < P ≤ 20 MPa 20
Punto triple del agua (0,01 °C)
Punto de fusión del hielo (0,00 °C) -80
+ 3 more
A2L ENVIRONNEMENT
Active
NF X 43-269
NF X 43-264
DIN EN ISO 16017-2
NF X 43-257
NF X 43-267
+ 1 more
Environmental noise — determination of s
UNE-EN ISO 3744
UNE-EN ISO 3746
UNE-EN ISO 11200
UNE-EN ISO 11201
+ 3 more
AB-EIC CONTROL REGLAMENTARIO
Active
UNE-EN ISO 16283-2
UNE-EN ISO 16283-1
UNE-EN ISO 16283-3
Absolutdruck p
abs
positiver Überdruck
Positiver Überdruck p e
Überdruck p
+ 3 more
ABIT Ingenieure Trautmann
Active
DIN ISO 8297
DIN 45645-1
DIN 45645-2
DIN 45680 Beiblatt 1
ISO 11338-2
+ 2 more
ABIT Ingenieure Trautmann
Active
BS EN ISO 16283-1:2014+A1:2017BS EN ISO
ISO 10052
BS EN ISO 16283-2:2020
DIN EN ISO 16283-3
DIN 4109-4
ABLE Calibration Services
Active
TEMPERATURE
PRESSURE
AC VOLTAGE (continued)
DC VOLTAGE
Generation only
+ 3 more
ABP Associates
Active
(HSG 248) – 2021
staining based on HSG 248
QP23 based on HSG 248
(PCM) based on HSG 248
No matching labs found.