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
๐Ÿ‡ฉ๐Ÿ‡ช DIN EN ISO 3382-2 ๐Ÿ‡ฌ๐Ÿ‡ง BS EN ISO 3382-2 ๐Ÿ‡ซ๐Ÿ‡ท NF EN ISO 3382-2 ๐Ÿ‡ฎ๐Ÿ‡น UNI EN ISO 3382-2 ๐Ÿ‡ช๐Ÿ‡ธ UNE EN ISO 3382-2 ๐Ÿ‡ณ๐Ÿ‡ฑ NEN EN ISO 3382-2 ๐Ÿ‡ฉ๐Ÿ‡ช DIN EN ISO 1996-2 ๐Ÿ‡ฌ๐Ÿ‡ง BS EN ISO 1996-2 ๐Ÿ‡ซ๐Ÿ‡ท NF EN ISO 1996-2 ๐Ÿ‡ฎ๐Ÿ‡น UNI EN ISO 1996-2 ๐Ÿ‡ช๐Ÿ‡ธ UNE EN ISO 1996-2 ๐Ÿ‡ณ๐Ÿ‡ฑ NEN EN ISO 1996-2
1,868 Accredited labs
20 Countries

Showing 301โ€“325 of 393 labs

UKAS 0131 South Wirral, GB
Joint IP/ASTM methods marked IP 195*ASTM D1078 ASTM D847 by titration ASTM D848 ASTM D 1353 + 3 more
View Profile
UKAS 0244 Broadlands, GB
(HSG 248) โ€“ 2021 ASB/SOP/OM8 based on HSG 248 (PCM) based on HSG 248
View Profile
UKAS 4412 Colbourne Crescent, GB
CHEM014 based on BS 4401 based on BS 4401 Part 4:1970 CHEM018 based on BS 4401 CHEM023 based on BS 4401- ISO 6579-1 + 3 more
View Profile
UKAS 1549 Bar Hill, GB
Method CBG-M-SOP-027 based on BS EN ISO AM01 based on BS EN ISO 4833-1: 2) Method CBG-M-SOP-038 based on BS ISO ISO 10272-2 Method CBG-M-SOP-007 based on BS EN ISO + 3 more
View Profile
UKAS 0820 South Wirral, GB
MPV Thrombozytenvolume Gas meters Power meter method LENGTH Waterdraw Method + 3 more
View Profile
UKAS 0032 Oldbury, GB
BS EN 286 - Simple unfired pressure BS EN 13445 Unfired pressure BS EN13480 Metallic industrial BS EN 12953 Shell boilers BS EN BS EN 12952 Water-tube + 3 more
View Profile
UKAS 2001 Whetstone, GB
ISO 14184-1 ISO 14184-2 BS EN ISO 1833-1:2020 BS EN ISO 105-B02:2014 BS 4407 + 3 more
View Profile
UKAS 31703 Eastbourne, GB
Surveying) based on HSG 248
View Profile
UKAS 1089 Burton-on-Trent, GB
(HSG 248) โ€“ 2021 SCI/ASB/003 based on HSG 248 (PCM) based on HSG 248 SCI/ASB/001 based on HSG 248
View Profile
UKAS 0148 Burton-upon-Trent, GB
(HSG 264, 2012) 5 of HSG 227 (2004)
View Profile

SOCOTEC UK

Active
UKAS 1015 Burton-upon-Trent, GB
DIN EN 13284-1 ENV/054 based on BS EN ISO 11731 DIN EN 14791 IEC 60519-11 + 3 more
View Profile
UKAS 4430 Swansea, GB
BS EN 1440:2016 + A1:2018 + EN ISO 23088:2020 Cylinders EN ISO 10460:2018 EN 14208:2004
View Profile
UKAS 4103 Bangor, GB
M002based on HSG 248 (HSG 248) โ€“ 2021 (PCM) based on HSG 248
View Profile
UKAS 0772 Rochford, GB
TORQUE increasing torque only.
View Profile
UKAS 2577 Redruth, GB
(HSG 248) โ€“ 2021 D3TA2 based on HSG 248 (PCM) based on HSG 248 D3TA8 based on HSG 248
View Profile

Scope iT

Active
UKAS 9086 Manchester, GB
Appendix 5 of HSG 227 (2004)) (HSG 264, 2012)
View Profile
UKAS 10483 Ossett, GB
(HSG 248) โ€“ 2021 SAC-SOP-15 based on HSG 248 SAC-SOP-07 based on HSG 248 staining based on HSG 248
View Profile
UKAS 2210 Wilton International, GB
(HSG 248) โ€“ 2021 DI/AN/ME/025 based on HSG 248 DI/AN/ME/001 based on HSG 248 DI/AN/ME/026 based on HSG 248 (PCM) based on HSG 248
View Profile

ServiceCal

Active
UKAS 0152 Heywood, GB
PRESSURE (contโ€™d) DC CURRENT DC VOLTAGE CFH-Gen, Macula-Degeneration Measurement + 3 more
View Profile
UKAS 2809 Copdock, GB
BS EN ISO 16283-1:2014+A1:2017BS EN ISO BS EN ISO 16283-2:2020 BS EN ISO 140-4:1998 BS EN ISO 717-2:2020 ISO 1407 + 1 more
View Profile
UKAS 9157 Sheffield, GB
LENGTH Plain plug gauges (parallel) Internal Caliper LENGTH (contโ€™d) + 3 more
View Profile
UKAS 1066 Leeds, GB
ASTM E 2149-20 BS EN ISO 20743:2021 Section ISO 14119 BS EN ISO 20645:2004 BS 1425-1:1991 Appendix A + 3 more
View Profile
UKAS 9248 Winall, GB
DIN EN 13821 Sigma-HSE (UK) Ltd DIN EN 14034-1 BS EN ISO/IEC 80079-20-2:2016 DIN EN 14034-2 + 3 more
View Profile
UKAS 0369 Wellington, GB
(HSG 248) โ€“ 2021 R24 based on HSG 248 staining based on HSG 248
View Profile
UKAS 4686 Ipswich, GB
BS EN ISO 16283-1:2014+A1:2017BS EN ISO BS EN ISO 16283-2:2020 BS EN ISO 140-4:1998 BS EN ISO 717-2:2020 ISO 1407 + 1 more
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