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 376โ€“393 of 393 labs

UKAS 1634 Whitley Bay, GB
(HSG 248) โ€“ 2021 ASB/10 based on HSG 248 (PCM) based on HSG 248 ASB/6 based on HSG 248 BS EN ISO 14644-1:2015 + 3 more
View Profile
UKAS 0593 Lutterworth, GB
TEMPERATURE parameters and ranges) indicators or recorders WEIGHING INSTRUMENTS
View Profile

Vantify

Active
UKAS 7892 Stoke Prior, GB
Appendix 5 of HSG 227 (2004) (HSG 264, 2012)
View Profile
UKAS 10213 Bishops Stortford, GB
(HSG 264:2012) 5 of HSG 227 (2004))
View Profile
UKAS 1249 Garston, GB
(HSG 248) โ€“ 2021 (PCM) based on HSG 248 P052 based on HSG 248
View Profile

W H Stephens

Active
UKAS 7855 Belfast, GB
(HSG 264, 2012)
View Profile

WSP UK

Active
UKAS 2538 London, GB
(HSG 248) โ€“ 2021 AFC based on HSG 248 (PCM) based on HSG 248 SSA based on HSG 248
View Profile
UKAS 1762 High Wycombe, GB
EN 13501-2 DIN 51363-2 BS 1363-1 BS 476: Part 21:1987 Section 5 ISO 834:1975:Sections 5, 6, 7 + 3 more
View Profile
UKAS 20481 Winterborne Zelston, GB
TEMPERATURE controllers, and recorders) RELATIVE HUMIDITY
View Profile
UKAS 21065 Cleckheaton, GB
Analystsโ€™ Guide (HSG 248) (PCM) based on HSG 248 staining based on HSG 248
View Profile
UKAS 7567 Newcastle-Under-Lyme, GB
(HSG 248) โ€“ 2021 SOP 12 based on HSG 248 (PCM) based on HSG 248 SOP 11 based on HSG 248
View Profile
UKAS 1830 Callington, GB
ISO 21528-2 BS ISO 4832:2006 BS ISO 16649-2:2001 Method No 2.9 based on BS EN ISO Method No 2.12 based on BS EN + 3 more
View Profile
UKAS 21819 Birchwood, GB
BS 1377-2:2022 BS 1377-9:1990 DIN EN 1097-5 BS EN ISO 17892-1:2014+A1:2022 purposes (BS 1377-2:2022
View Profile

Winkhaus (UK)

Active
UKAS 1989 Kettering, GB
DIN EN 12046-2 DIN EN 12094-8 DIN EN 949 BS 6375-2:2009 DIN EN 950 + 3 more
View Profile
UKAS 0462 Ballyclare, GB
TIME INTERVAL BetriebsรผbertragungsmaรŸ TEMPERATURE ROTATION SPEED
View Profile

Wood Group UK

Active
UKAS 4482 Glasgow, GB
IEC 61400-12-1 IEC 61400-12-3 IEC 61400-50 IEC 61400-12 IEC 61400-50-2 + 3 more
View Profile

i2 FAST

Active
UKAS 10852 Hemel Hempstead, GB
BS 4401-1:1998 Using N008-1 based on BS EN ISO 12966-4 2015 N008-2 based on BS EN N011 based on BS 4401-9:1975 and BS 770- + 3 more
View Profile
UKAS 1916 Hebden Bridge, GB
on BS 4401:Part 3:1970(1986) ISO 12966-1:2014 and ISO 12966-4 CH 4026 based on BS 5766:Part CH 4001 based on BS EN 12014- + 3 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