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
1,868 Accredited labs
20 Countries

Showing 1,301–1,325 of 1,868 labs

QS-Grimm

Active
DAkkS D-K-15159-01-01 Gutach Schwarzwaldbahn, DE
Parallelendmaße * 0,5 mm DIN EN ISO 3650:1999 Zylindrische Normale 1 mm Innenzylinder * > 100 mm + 3 more
View Profile

QUACER

Active
ENAC LE1517 Onda, ES
UNE-EN ISO 140-5 UNE-EN ISO 16283-3 UNE-EN ISO 16283-2 UNE-EN ISO 140-7 UNE-EN ISO 16283-1 + 1 more
View Profile

QUALILAB

Active
ACCREDIA 00888 Capriano del Colle, IT
EN 12966: 2014 Section 4.5.4 DIN EN 55025: 2018 DIN EN 60068-2-30 (CISPR 25:2002) Section 6 ISO 11452-4: 2020 + 3 more
View Profile

QUALIO

Active
COFRAC 1-7474 Besancon Cedex, FR
EN 13087-2 NF T 90-003 NF T90-015-1 NF T 90-107 DIN EN ISO 10523 + 3 more
View Profile

QUALYSE CHAMPDENIERS ST DENIS

Active
COFRAC 1-7303 Champdeniers, FR
ISO 13320 VDE 414-9-11 NF V08-250 ISO 19343 DIN EN ISO 7899-1 + 3 more
View Profile

QUANTUM INNOVATIVE, S.L. (CIMALab)

Active
ENAC LE2055 Nigrán, ES
UNE-EN 1789
View Profile

Qopas

Active
DAkkS D-K-12048-01-00 Driedorf, DE
Koordinatenmessgeräte geräte mit einem Chorus, Help-PJM von DEA Hexagon Metrology S.p.A., Turin, I Associates EMS Products, ≤ 1500 mm + 3 more
View Profile

Quality Consultants (NI)

Active
UKAS 2705 Dundonald, GB
(HSG 248) – 2021 (PCM) based on HSG 248 QSOP 03 based on HSG 248
View Profile

Questmed

Active
DAkkS D-PL-18753-02-00 Kleinmachnow, DE
ISO 22679 ISO 7207-1 ISO 14243-1 ISO 14243-2 ISO 14243-3 + 3 more
View Profile

R-TECH Services

Active
UKAS 2594 Margam, GB
ÖNORM EN ISO 17637 BS EN ISO 15614-1:2017 ASTM A 370 DIN EN 10080 BS EN ISO 9015-1:2011 + 3 more
View Profile

REHAU Industries SE &

Active
DAkkS D-PL-22158-01-01 Rehau, DE
DIN EN ISO 2808 DIN EN ISO 11885 DIN EN 12697-28 DIN EN ISO 1172 DIN EN ISO 2578 + 3 more
View Profile

REMINEX - CENTRE DE RECHERCHE

Active
COFRAC 1-0789 Reminex - Centre De Recherche - Bp 469 Marrakech Medina | - Marrakech | Maroc, MA
NF T 90-003 DIN EN 26777 DIN EN ISO 10523 DIN EN 846-7 DIN EN 25814 + 3 more
View Profile

RFI S.p.A.- Gruppo Ferrovie dello Stato Italiane - LABORATORI DI INNOVAZIONE, PROVE E SPERIMENTAZIONI di RFI

Active
ACCREDIA 00147 Roma, IT
DIN 1048-2 DIN ISO 48-4 DIN EN 13146-7 DIN EN 13180 DIN EN ISO 868 + 3 more
View Profile

RINA CONSULTING - Centro Sviluppo Materiali SpA

Active
ACCREDIA 01411 Roma, IT
DIN EN ISO 6508-1 ASTM E1019-24 ISO 13320 ISO 6892-2 (BS EN ISO 6892-1: 2019) + 3 more
View Profile

RIO

Active
DAkkS D-K-17376-01-00 Siegen, DE
Parallelendmaße * 0,5 mm DIN EN ISO 3650:1999 > 100 mm > 500 mm > 550 mm + 3 more
View Profile

RIVACOLD SRL

Active
ACCREDIA 01454 Vallefoglia, IT
DIN EN 16825 ISO 22041 EN ISO 22043 DIN EN 13771-1 DIN EN 14511-2 + 3 more
View Profile

RMA Mess- und Regeltechnik

Active
DAkkS D-K-20908-01-00 Rheinau, DE
Durchfluss von Gasen Volumendurchfluss 50 m³/h Railway brakes — brake performance (UIC (Hochdruck Erdgas 5 bis 51 bar) + 1 more
View Profile

ROTA YOKOGAWA

Active
DAkkS D-K-17720-01-00 Wehr, DE
Masse m strömender − Durchfluss von Flüssigkeiten Durchfluss von 1) In den CMC sind die erweiterten Messu Massedurchfluss dm / dt + 3 more
View Profile

ROVIRA EQUIPOS

Active
ENAC LC10.178 Madrid, ES
CEM Ed
View Profile

RSK Environment

Active
UKAS 23462 Coventry, GB
Analysts’ Guide (HSG 248) (PCM) based on HSG 248
View Profile

Radiomotive

Active
ACCREDIA 02089 Fino Mornasco, IT
ETSI EN 301 489-6 DIN EN 61326-2-6 IEC 61326-3-1 IEC 61326-3-2 IEC 60669-2-5 + 3 more
View Profile

Ramcare

Active
UKAS 0505 Lancing, GB
DC CURRENT DC VOLTAGE thermometer Pt100 ROTATIONAL SPEED Generate + 3 more
View Profile

Ramm Ingenieur

Active
DAkkS D-PL-20808-01-00 Wuppertal, DE
DIN 45635-1 DIN 45645 Teil 1
View Profile

Regierungspräsidium Kassel Hessische Geräteuntersuchungsstelle

Active
DAkkS D-PL-19353-02-02 Kassel, DE
IEC 60335-1: 2010 VDE 0700-1 DIN EN 60335-2-2 DIN EN 60335-2-3: 2002 DIN EN 60335-2-4 + 3 more
View Profile

Renishaw

Active
UKAS 4312 Wotton-under-Edge, GB
volume (CMM’s)
View Profile

No matching labs found.

Industries

Audio and sound system design Public address and emergency systems Telecommunications and broadcasting Educational and institutional facilities Aviation and maritime communication

Related Standards

  • ISO 3382-2 Acoustics - Measurement of room acoustic parameters - Part 2: Reverberation time in ordinary rooms
  • ISO 1996-2 Acoustics - Description, measurement and assessment of environmental noise - Part 2: Determination of sound pressure levels
  • EN 60268-1 Sound system equipment - Part 1: General

Other Test Methods

0 labs selected
Compare