Improving the acoustic environment of schools for pupils and teachers

1. LARCI seminar Research for Education - Making a Difference 10 November 2005 Improving the acoustic environment of schools for pupils and teachers Bridget Shield & Anne Carey London South Bank University Julie Dockrell & Kate Rigby Institute of Education, University of London

2. Outline of talk • Acoustic requirements for classrooms • Background to EPSRC project - previous research • EPSRC project - aims and methodology • Acoustic surveys of classrooms • Remedial acoustic treatments to classrooms • Teachers’ voice levels • Amplification in the classroom • installation • benefits • Summary and conclusions

3. Acoustic requirements for classrooms • To provide good listening and speaking conditions a classroom must have • Low background noise • Short reverberation time • Good sound insulation • between classrooms to minimise transmission of classroom noise • of external façade to minimise intrusion of external noise

4. School buildings built since 2003 must comply with the Building Regulations Legal requirements for acoustic design of new schools specified in Section 1 of Building Bulletin 93 Building Bulletin 93 (DfES, 2003)Acoustic design of schools

5. Indoor ambient noise levels Airborne sound insulation Impact sound insulation Reverberation time Sound absorption in corridors and stairwells Speech intelligibility in open plan spaces Building Bulletin 93 (DfES, 2003)Acoustic design of schools DfES kept informed of results of EPSRC project which will inform any revision of BB 93

6. Two major research projects on classroom acoustics • The effects of noise on the attainments and cognitive performance of primary school children • Department of Health/DEFRA 1999-2001 • Acoustic design guidelines and teacher strategies for optimising learning conditions in classrooms for hearing and hearing-impaired children • EPSRC (EQUAL) 2002 - 2005

7. Background - previous study Methodology • Noise surveys outside 142 primary schools in 3 London boroughs • Noise surveys inside 140 classrooms in 16 schools in two boroughs • Questionnaire survey of all Year 2 children in one borough (N>2000) and their teachers (N>50) • Comparison of noise levels with SATs results • Experimental testing of mainstream and SEN children in typical noise conditions

8. Background - previous study results • Children are exposed to higher noise levels at school than recommended by BB 93 and WHO • Children are aware of noise and annoyed by specific noise sources • Ease of listening in the classroom is related to external noise levels • Exposure to noise affected performance on academic tasks • Classroom babble affects performance on verbal tasks • External environmental noise affects non-verbal tasks and speed of processing tasks • Children with special educational needs are differentially affected • Majority of teachers experience voice and throat problems

9. External noise (142 schools) Internal noise (16 schools) Effects of noise on Key Stage 2 SATs Results hold when data corrected for socio-economic factors

10. Effects of noise on speed processing task Changes in test scores in noise

11. Effects of noise on children with special educational needs Results of experimental testing

12. Acoustic design guidelines and teacher strategies for optimising learning conditions in classrooms for hearing and hearing-impaired children Aims of EPSRC EQUAL project • To identify those acoustic parameters that are most applicable to children’s hearing and listening in classrooms • To investigate ways of improving the acoustics in classrooms • To investigate the use and effectiveness of classroom amplification systems • To investigate the effects of acoustics on teachers’ voices • To develop new word tests for hearing and hearing impaired children

13. Acoustic design guidelines and teacher strategies for optimising learning conditions in classrooms for hearing and hearing-impaired children Aims of EPSRC EQUAL project • To identify those acoustic parameters that are most applicable to children’s hearing and listening in classrooms • To investigate ways of improving the acoustics in classrooms • To investigate the use and effectiveness of classroom amplification systems • To investigate the effects of acoustics on teachers’ voices • To develop new word tests for hearing and hearing impaired children

14. Acoustic design guidelines and teacher strategies for optimising learning conditions in classrooms for hearing and hearing-impaired children Methods used in EPSRC EQUAL project • 39 mainstream and special schools in London, Herts, Berks, Hants • Acoustic surveys of 55 classrooms in 25 schools • Measurements of voice levels of 36 teachers • Study of installation and use of amplification systems (SFS) in ~20 schools • Questionnaire surveys of children with and without SFS • Cognitive testing of children with and without SFS • Structured observation of children with and without SFS

15. Acoustic survey of 55 classrooms: reverberation times 18 out of 44 untreated rooms meet BB 93 criterion All treated rooms meet criterion

16. Teachers’ voice levels M F

17. What can be done to improve the acoustic conditions for teaching and learning? • For teachers • For children • mainstream • with permanent hearing loss • with temporary hearing loss • with language problems • with attention difficulties • Two approaches investigated: • Increasing acoustic absorption to reduce reverberation time • Using amplification/sound field systems in the classroom

18. Effectiveness of acoustic treatment Acoustic absorption can be added to the ceiling (as here) or to the ceiling and walls No absorption: RT = 1s With absorption: RT = 0.5s

19. Effectiveness of acoustic treatment Measurements in 7 untreated and 6 matched treated classrooms

20. Amplification in the classroom What is a Sound Field System (SFS)? • A SFS is essentially a simple speech reinforcement system used by the teacher. • Three main types: - 4 small moving coil loudspeaker - single column loudspeaker - multiple flat panel (DML) in ceiling • Systems usually consist of boom or collar mounted directional radio mic & transmitter, radio mic receiver, mixer/amp & loudspeakers. • Typical price £1000 - £1500 per system.

21. Amplification in the classroom Why are SFS installed? • To provide all pupils in the classroom with equal speech signal from the teacher • Installed in classrooms where there is a hearing impaired child • Installed for use by a teacher with voice problems • Systems are installed: for individual pupils, to improve acoustics by the school, or in a blanket manner by LEA. • General misconception that SFS solve all acoustical problems

22. Amplification in the classroom Some systems installed in suitable rooms and may be working well and making a difference Some systems installed in very small rooms with low background noise – any point? Some systems installed in large rooms with long RT – potentially make things worse Where are SFS installed? SFS installed across whole range of classrooms measured

23. Amplification in the classroom SFS were not used in about half of the classrooms in which they were installed • Acoustic conditions in the classroom are suitable • They are installed correctly, in appropriate places in the classroom • They are installed in consultation with the teachers who will be using them • Teachers are given training in their use • If they work! Sound field systems can only be used successfully if

24. Examples of poor installation/communication The loudspeakers have been installed in areas where class teaching does not take place

25. Example of poor training of the teacher The loudspeakers have been decorated for Christmas! • Of teachers surveyed • 56% not given any training in use • of systems • 63% not consulted about placing • of systems

26. Evaluation of sound field systems • Schools in Hertfordshire and London • Effects on children’s listening • questionnaire survey of children in mainstream (Nq=1396) and special schools (Nq=128) before and 6 months after installation • Effects on children’s behaviour • Structured observation of pairs of hearing and hearing impaired children in 9 classrooms with and without SFS • Effect on children’s performance - SFS on/off • testing of 380 children (24 with SEN) over 3 week period • spelling, oral comprehension, speed of processing • Effect on children’s learning - 6 months after installation • testing of 280 children (41 with SEN) before and after • spelling, oral comprehension, speed of processing, reading, maths

27. Evaluation of sound field systems - impact on listening • Children in SFS classrooms reported improvements in hearing teacher in 3 out of 8 situations when teacher is speaking • writing on board • working in groups • children making noise outside classroom • No changes for hearing impaired children • small sample and possible technical difficulties • Children in special schools reported improvements when • cannot see teacher’s face • writing on board • moving around classroom • children making noise outside classroom Benefits in hearing teacher for majority of children

28. Evaluation of sound field systems - observational results • No changes between classrooms with and without SFS in • adult involvement • type of task performed by children • type of sound made by children • underlying teaching and learning activities • In SFS classrooms • children's hands raised less often • children more attentive • children respond more quickly to teacher • children less distracted by external noise Beneficial effects for all children

29. Evaluation of sound field systems - effect on children’s performance and learning Performance (SFS on/off) • Improvements in spelling for all children • no change in comprehension and speed of processing • Improvements in spelling and comprehension for SEN children • no change for speed of processing • Effects greater for SEN children Learning (changes after 6 months) • No changes in spelling and maths • Significant improvements in comprehension and speed of processing Improvement in processing oral input, particularly for children with additional learning needs

30. Summary and conclusions • The acoustic conditions in the majority of existing classrooms do not meet current regulations • Reducing noise and reverberation would benefit children’s learning and teachers’ health • Acoustic treatments can be applied to remedy the situation • Amplification in the classroom can improve the listening and learning situation for mainstream children and those with additional learning needs • Amplification is not a remedy for poor acoustics • In order to be used successfully amplification must be installed • in classrooms which are acoustically suitable • in appropriate positions in the classroom • in consultation with the teacher • with adequate training of teachers

31. Current and further EPSRC research • The acoustics of open plan classrooms (LSBU, EPSRC studentship, 2003 - 2007) • Modelling performance of SFS (LSBU, EPSRC studentship, 2005 - 2008) • The acoustic design of secondary schools (LSBU, IoEd, Univ of Salford, new application)

32. Help needed • Access to schools • Opportunities to do ‘before’ and ‘after’ testing (acoustic and psychological) where remedial treatment/structural alterations planned • Access to classrooms to test new word test

33. LARCI seminar Research for Education - Making a Difference 10 November 2005 Acknowledgements This work has been funded by the Engineering and Physical Sciences Research Council. Contacts Julie Dockrell: j.dockrell@ioe.ac.uk Bridget Shield: shieldbm@lsbu.ac.uk