Acoustics - listening and learning: All

One of the critical requirements for effective learning is that children and young people hear clearly what is said to them. Far too many pupils in schools do not make the progress of which they are capable because they cannot consistently hear speech clearly. Can all your pupils hear intelligibly what you and their fellow pupils are saying to them wherever they or you are in the classroom? Do you have to repeat your instructions, advice, questions and answers, because your pupils don’t hear you the first time? Do they have to repeat what they say to you because you are unable to hear clearly what they are saying? Do you know which of your pupils are having problems hearing you? There are several problems associated with pupils struggling to hear speech clearly and there are a number of solutions that can help overcome many of these problems.

This MESHGuide has been designed to cover a wide range of issues associated with classroom acoustics in schools and the impact the quality of speech intelligibility has on deaf children’s learning in particular. It presents the most up-to-date research in an easily accessible way, thus enabling all readers to understand the topic, discover the key characteristics of the issues surrounding the topic and, where appropriate, to determine policy and practice in schools. It is intended to stimulate increased understanding in the importance of providing excellent acoustics and will hopefully lead to improvements in classroom acoustics where necessary. The intention is that all children and young people, including those with any level of deafness, will be able to enjoy the best possible quality sound reception.

We hope the content of this MESHGuide will stimulate teachers to feed in their own classroom experience in the form of case studies that both exemplify and challenge the findings of the research contained in the Guide. Thus, continually expanding the body of knowledge in this area. This MESHGuide will only have achieved its aims if it is embraced by all those interested in classroom acoustics as a living, dynamic repository of current knowledge and best practice and as a place to share their own case study findings.

The Guide is set out in a way to allow you, the reader, access to the areas of most immediate interest to you. It provides links to some of the key publications and research where you can explore the topic in as much depth as you wish. It includes information on children’s hearing and learning, the characteristics of the transmission of the voice, what counts as excellent acoustics and speech intelligibility and the impact the quality of acoustics has on teaching and learning. The interventions available to improve acoustics and speech intelligibility and sample case studies exemplify the research presented in the Guide.

The authors of this Guide will work to continually develop and improve its content and actively welcome comment from all readers on how improvements might be achieved.

This guide is one in a series of Deaf Education MESHGuides.
 

This column provides a brief introduction to why good acoustics are important and provides links to some of the key publications and research available.

Whilst research into the impact on learning of improved acoustics and speech intelligibility has been, and continues to be, carried out, the evidence is somewhat more anecdotal than proven by statistics. We have endeavoured to list below those sources which we feel you will find the most helpful when visiting the various sections of this Acoustics Guide.

This column provides a brief history of acoustics in schools. It draws together evidence that has been collected over a number of years encompassing the impact of historical neglect in providing good acoustics in schools, the impact of poor acoustics on teaching and learning and what changes can be made to improve the experience of teachers and pupils.

This column provides information on the characteristics of the transmission of voice, what is considered to be a good acoustic environment, and information on speech intelligibility.

In order to appreciate the problems associated with poor acoustics, it is necessary to understand the human and physical components of the acoustic environment. It also sets out the soundscape in which we all work and the acoustic standards that have been determined to ensure teachers and pupils can work effectively in the education environment.

This column provides information on how to manage noise and the interventions available to improve acoustics and speech intelligibility.

It details recent research on the variety of materials and technologies that can be introduced into learning spaces and the impact they can have on the quality of teaching and learning.

This column provides the first of what will be a growing number of examples of direct evidence of the impact of interventions, drawn from classroom-based research, that help exemplify the research presented in this guide. It includes a case study showing the benefits of installing acoustic materials and soundfield systems.

The authors would welcome further small-scale case studies in the field of acoustics and speech intelligibility, to include in this guide. Please submit these to exec@batod.org.uk

In the BATOD Magazine there have been articles presented by Teachers of the Deaf and other professionals in deaf education that prove useful in supporting the provision of better acoustics or supportive technology such as FM and soundfield systems. The research links provide the academic evidence. Contact BATOD exec@batod.org.uk for copies of articles providing evidence underpinning this MESHGuide.

Historically schools were built without regard for the need of good acoustics and listening conditions.

Below are some links showing the how poor the acoustics have been, and how governments have recognised the need to legislate and improve the listening environments in learning spaces.

• Earthman, G. (2004) Prioritization of 31 Criteria for School Building Adequacy American Civil Liberties Union Foundation of Maryland Baltimore, MD 21211
• Baker, L. (2012) A History of School Design and its Indoor Environmental Standards, 1900 to Today. Washington: National Clearinghouse for Educational Facilities
• ‘Building Schools for the Future’
• The Priority School Building Programme (PSBP) is addressing the needs of schools most in need of urgent repair. This link provides further links to relevant government documentation. Guidance on the Priority School Building Programme provides an overview of the programme and information about Private finance funding - PF2, the Aggregator model, Capital funding and Selected contractors - capital funded batches
• Essex Study

The following factors need to be taken into consideration when thinking about speech intelligibility.

Speech banana

The speech sounds (phonemes) of a language occur across a range of sound frequencies and over a range of sound intensities; from low frequency to high frequency (eg 50Hz to 5KHz) and from low intensities to higher intensities (28dBHL word endings to 65dBHL word initial sounds). This is shown as a banana shape on a Pure Tone Audiogram (PTA), based on speech delivered at 1 metre from the ear at a ‘normal’ intensity with no competing noise. This is referred to the speech banana. 

For the brain to perceive a particular phoneme it must hear the key frequency/frequencies at about 12dB louder than the ear’s threshold of hearing. The PTA threshold is a reaction to a sound, the perception of a phoneme requires information to be analysed by the brain necessitating a 12dB louder input. This is why the Speech Banana shape showing individual phonemes - and the Dotty Audiogram (see below) - is ‘quieter’ than the one showing the effect of all sounds.

Adults with a fully developed speech and language system learned through normal hearing can follow speech (to a degree) even when reduced to hearing 70% of the phonemes. Deaf children are

1. hearing a reduced quality of speech through hearing devices

2. using a decoding system of delayed language development

3. trying to learn new vocabulary and language about new subject areas every day.

Peter Keen, Consultant Educational Audiologist, argues that this requires hearing at least 90% of phonemes with minimal background noise interference. He has developed a more accurate speech banana for the sounds of English, giving a clearer picture of what deaf children are accessing with and without their hearing devices, predicting phonemes not heard /mis-heard, using Aided Levels or demonstrating actual phonemes mis-heard or not heard from Speech Discrimination testing (eg AB word lists). The Dotty Audiogram uses the Aided Levels to show the percentage of phonemes likely to be heard in perfect listening conditions. 

Teachers of the Deaf and Educational Audiologists use both of these tests to help fine-tune hearing aid programming and predicting areas where accessing language might be difficult.

These results are also used to predict the need for Assistive Listening Devices and/or sound treatment to a learning area when considering how the acoustic information shows potential access to speech.

Ling sounds

The Ling 6 Sound Test, designed by Daniel Ling, is a way of checking that speech sounds across the whole speech spectrum are likely to be heard. It can be used as a check that the hearing device is amplifying and programmed appropriately. The three vowels and three consonants used - 'mm', 'oo', 'ah', 'sh', 'ee', 'ss' - have sound frequency information specific to areas of the Pure Tone Audiogram. For an analysis of the test and how to use and interpret the results, see The Ling 6 Sound Test, by Peter Keen, Consultant Educational Audiologist.

Assessing speech discrimination

Another way of assessing speech intelligibility is to do speech discrimination tests. This is an important part of the role of a Teacher of the Deaf (ToD), particularly working in mainstream settings. Room acoustics and the impact of factors such as reverberation time on the student’s ability to hear should be assessed. Using a consistent method to assess speech discrimination allows a measure to be made of the impact on listening of a long or a short reverberation time. An acoustically good classroom will enable students to hear more clearly and accurately so their scores, for example in the BKB sentence test will be better; this supports ToDs in their requests that their students are timetabled for rooms that are proved to be acoustically good. There is a series of articles available from the British Association of Teachers of the Deaf Magazines which provide more information on speech discrimination tests using BKB sentences. 

Impact of noise and distance

Especially in relatively poor acoustic listening conditions, the positioning in the classroom is critical. Sound energy decreases the further away from the source one goes. The doubling of the distance will result in a decrease in 6dB. (The inverse square law) 

Do you find yourself as a teacher witnessing that at least some of your pupils are not attaining the standards of which they are capable? Is it at least in part due to the difficulty they experience daily of not hearing clearly what is said to them by you or any other person addressing the class? Then you need to take action.

These practical suggestions to manage noise are taken from Stuart Whyte’s article ‘Managing Noise’, published in the BATOD magazine September 2011. Stuart Whyte is a Qualified Teacher of the Deaf and Educational Audiologist. Here he looks at the nature of sound in learning settings and provides some practical suggestions for improving conditions for children and staff affected by noise.

Reducing the impact of noise

Different age groups and activities generate different levels of noise. We know that children are aware of and annoyed by noise that distracts them. Age appropriate strategies can be employed to support children to be more self-aware of noise.

• Pupil talk is important but do teach children and young people the meaning of different working noise levels. Use recorded sound samples or role-play to model what you mean. For younger children discuss stories such as ‘The Quiet Woman and the Noisy Dog’ by Sue Eves or ‘Hannibal's Noisy Day by Anne Adeney.

• Define acceptable limits; for example, use ‘mute’, ‘whisper voices’, ‘partner voices’ and ‘group voices’ for working noise ranging from no talking through to conversational level; use ‘playground/break-time voices’ for levels unacceptable in the classroom.

• Use visual indicators of noise levels such as a ‘noiseometer’ or traffic light system to represent the range. This can be a paper, card or whiteboard versions of ‘classroom management aids’ (or there is even an ‘AudioTools’ sound level meter traffic light app for iPod Touch and the iPhone).

• Support your spoken instructions with accessible visual cues so pupils can see the steps to completing tasks within the lesson. Have clear systems for pupils to show their understanding and ask for help.

• Distance is critical; deliver spoken instructions near to a deaf child. Provide good access to lip pattern and facial expression; don’t ‘walk and talk’!

• Co-ordinate your learning activities if teaching in open-plan areas – don’t start your music lesson if the neighbouring class are reading!

• Turn off the digital projector or computer(s) when not in use to avoid fan noise and save energy!

• Close doors or windows as far as possible.

• Carpets, curtains, soft furnishing, soft covers on tables, fabric on walls, soft fibre display boards, and mobiles or materials hung from the ceiling can help. However, if suspending items, ensure materials are not a fire hazard and not likely to activate the motion sensor of the school alarm system at night!

• Interference by noise affects working memory. A poor acoustic environment affects pupils in different ways; be aware that verbal tasks like reading and spelling are affected by speech noise (classroom babble), while non-verbal tasks may be more affected by environmental noise.

• Share good practice with colleagues and talk about noise awareness across the school. Consider establishing 'Quiet Zones' in the building. The NDCS ‘Here to Learn’ DVD includes a section that shows how some simple steps can reduce noise in a classroom.

• Some children will benefit from personal radio aid systems or soundfield amplification within the classroom. Personal radio aid systems will provide the best signal-to-noise ratio. However, careful thought should be given to the provision and maintenance of such systems. They need to be set up for the amplification needs of individual deaf children and access to a Qualified Teacher of the Deaf or Educational Audiologist is essential.

Classroom acoustics should be considered a critical variable in the educational achievement of children. We know that staff and children experience difficulties in learning settings with excessive noise and reverberation levels, so essential services for deaf children and measures to reduce the risks to health and achievement should be maintained.

• Classroom Audio Distribution (Sound Field) Case Study - 2016

  Manchester Communication Academy (MCA)

  This case study and video provides evidence of how a new secondary school in Manchester that has some very large teaching spaces (4-5 classes per space), has been able to overcome the problems of excessive noise and poor levels of speech intelligibility, through the installation of classroom audio distribution systems.

  The Lightspeed Redcat Access and Flexcat systems have significantly improved the learning environment for both teachers and students, especially those with hearing impairment, SEN conditions and EAL challenges.

• Managing Noise / Sound Advice articles by Stuart Whyte (see Interventions)

• Acoustic Treatment in the rooms we have by Shane Cryer (PowerPoint)

• BB93 sound simulations

• Essex Study A YouTube presentation Simon Smith of Sweyne Park School gives his experience of teaching in the classrooms treated as part of the Essex Study, but also explains the importance of a good acoustic environment when teaching. "You can hear who's talking, you can deal with with a quiet word". Pupils Grace Gillmore and Eleanor
• The Essex study - sound treatment in rooms A balloon is burst in four classrooms with varying degrees of acoustic treatment - the sound quality in each room is clearly related to the treatment!

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Wroblewski, M., D. E. Lewis, D. L. Valente and P. G. Stelmachowicz (2012). "Effects of reverberation on speech recognition in stationary and modulated noise by school-aged children and young adults." Ear Hear 33(6): 731-744.

Whyte, S. (2010) A guide to research on soundfield systems.

Zanin, J. & Rance, G. (2016) ‘Functional hearing in the classroom: assistive listening devices for students with hearing impairment in mainstream school settings’ Int. J. Aud. 55 (12): 723-729

Zannin, P.H.T., Zwirtes, D.P.Z.,  & Passero, C.R.M. (2012) Assessment of Acoustic Quality in Classrooms Based on Measurements, Perception and Noise Control,  Chapter 10 in Noise Control, Reduction and Cancellation Solutions in Engineering

Suppliers websites which carry research and reports about that company’s products in relation to this topic.

Connevans

Ecophon Saint Gobain

Lightspeed Technologies

PCWerth

Phonak

Several studies and written reports over the last 40-50 years have shown the extent to which poor classroom acoustics impact negatively on children’s learning performance.

The research of Ross (1972) and Ross, Giolas& Carver (1973) presented, for the first time, powerful evidence of the effect of classroom conditions on speech intelligibility. When these research studies were undertaken, there were no articles available dealing with the behaviour of sound in a classroom and its impact on children and nothing on reverberation time and critical distance.

• Ross, M. (1972) 'Classroom acoustics and speech intelligibility in J Katz (Ed.) Handbook of Clinical Audiology. Baltimore

• Ross, M., Giolas, T.G. & Carver, P.W. (1973) The effect of classroom conditions on speech intelligibility: A replication in Language and Hearing Services to Schools, 4, 72-76

Research to show that poor academic outcomes are partly due to poor acoustic accessibility are documented by Dockerell & Shield (2008) in ‘The effects of environmental and classroom noise on the academic attainments of primary school children.’They found that external noise can have a significant negative impact upon performance and that test scores were also negatively affected by internal classroom noise. 

Other studies showing links to behaviour, listening and communication, and social /emotional /mental health:

• Behaviour: Maag J.W. & Anderson J.M. (2006) ‘Effects of Sound-Field Amplification to Increase Compliance of Students With Emotional and Behavior Disorders.’ Behavioral Disorders, 31(4), 378-393.

• Communication: Cornwell S. & Evans C.J. (2001) ‘The effects of sound-field amplification on attending behaviours.’ Journal of Speech-Language Pathology & Audiology, 25(3), 135-144.

• Social/emotional/mental health: Klatte M., Hellbrück J., Seidel J., Leistner P. (2010). ‘Effects of classroom acoustics on performance and well-being in elementary school children.’ Fraunhofer Journal Article: eb 42 (2010), No 5, pp.659-692

The key components that create a classroom acoustic are:

• the room design
• the levels of background noise - internal/external noise IANL (indoor ambient noise level)
• the levels of reverberation

Reverberation times

It the room is reverberant, the sound reverberating or echoing around the room will have a poor effect on speech intelligibility and listening. Critical distance is the distance from the speaker in a room, where the speaker’s voice level is equal to that of the reverberation or sounds bouncing off hard surfaces. Beyond that, speech becomes less intelligible. Boothroyd’s research (2004 and 2012) investigates the characteristics of a range of speech sounds/critical distance and information on the physics of the human voice and the distances it remains intelligible within learning spaces.

Boothroyd, A (2004) ‘Room acoustics and speech perception’. Seminars in Hearing, Vol 25 pp155-166, New York: Thieme Medical Publishers.

Boothroyd, A.(2012) ‘Speech perception in the classroom’ in Smaldino, J.and Flexer, C. (ed.) (2012) Handbook of Acoustic Accessibility: Best Practices for Listening, Learning and Literacy in the Classroom. New York: Thieme Medical Publishers (ISBN 978-1-60406-765-1). This also gives more general information on the physics of classroom acoustics and contains more recent examples of the application of the physics of critical distance and pupils’ ability to hear clearly what is said to them in learning spaces.

Whitmal and Poissant(2009) investigated the effects of the distance between speaker and listener on the perception of speech of cochlear implant wearers.

Whitmal N.A. & Poissant S.F. (2009). ‘Effects of source-to-listener distance and masking on perception of cochlear implant processed speech in reverberant rooms’. Journal of the Acoustical Society of America, 126(5), 2556-2569.

Signal to noise ratio

A good signal to noise ratio is important if pupils are to have good access to speech and learning. The teacher’s voice at the pupils’ ears should ideally be at least 10dB above the background noise for hearing children and at least 15-20 dB for hearing impaired children. There are Apps available that will give an idea of decibel levels.

A study giving a practical consideration of signal to noise ratios in working classrooms was undertaken at Manchester University. It explains about Classroom Acoustics (p4) and Classroom Signal to Noise Ratio Measurement Methods (p6).

McCracken, W., Roberts, A. and Wilding, T. (2012) ‘Study of FM in Real World Settings’ Oticon Foundation

Classroom design

The size and shape of a room, whether it is enclosed or open plan, the height and slope of the ceilings, the number of windows and doors, the furniture and soft furnishings etc all influence the acoustics of a room. A small, square enclosed room, with a low flat ceiling and soft furnishings will have better room acoustics than a large open plan room with no absorbent materials.

Where the design of a classroom results in poor acoustic conditions then the installation of both sound insulation materials and sound field and personal radio aid systems can to greater or lesser extent overcome the problems of the noise and/or reverberation that is acting as a barrier to pupils hearing and learning. These palliative tools are discussed in more detail in the Interventions and Case Studies columns.

Classroom Audio Distribution (Sound Field) Case Study - 2016. 

This case study and video provides evidence of how a new secondary school in Manchester that has some very large teaching spaces (4-5 classes per space), has been able to overcome the problems of excessive noise and poor levels of speech intelligibility, through the installation of classroom audio distribution systems. The Lightspeed Redcat Access and Flexcat systems have significantly improved the learning environment for both teachers and students, especially those with hearing impairment, SEN conditions and EAL challenges

Listening to Learn: An Evaluation of Classroom Audio Distribution Technology for Enriching Teaching and Learning

A study which involved 12 schools across England and Scotland

As the detrimental impact of poor acoustics on pupil learning became clear, a variety of solutions developed over a period of years. These included the development of regularly updated school acoustic standards and guidance by Governments (see Context column), acoustic materials and the use of soundfield technology (see Interventions column). You will also find details of the impact on learning of these product developments in the Case Studies column.

Here are some of the main points from the legislation and guidance on acoustics standards for school. The requirement that particularly applies to schools is Building Regulations 2000 Approved Document E which has the descriptive statements: 

• E4. (1) Each room or other space in a school building shall be designed and constructed in such a way that it has the acoustic conditions and the insulation against disturbance by noise appropriate to its intended use.
• E4. (2) For the purposes of this Part – ‘school’ has the same meaning as in Section 4 of the Education Act 1996 [4]; and ‘school building’ means any building forming a school or part of a school.

E4 does not have defined numerical standards, but states that the acoustic conditions and sound insulation of learning spaces ‘shall be … appropriate’. The Premises Regulations and School Standards similarly state that conditions ‘must be suitable for learning’ (see below).

These statements are open to interpretation as 'appropriate' and 'suitable' are not defined and may vary between school building sites. To help inform designers, quantitative acoustic standards for new and refurbished schools have been devised and are set out in Building Bulletin 93 (2014). Compliance with the standards in BB93 is deemed by the Secretary of State for Education to be the usual way to satisfy E4(1). The performance standards for indoor noise levels, sound insulation and the control of reverberation are mandatory, but performance criteria for speech intelligibility and rain noise are guidance only.

The School Premises Regulations (SPR 2012) and the Independent School Standards (ISS 2014) apply to existing schools. The acoustic conditions and sound insulation of each classroom or other teaching space must be suitable for learning. Building Bulletin 93, Acoustic Design of Schools - Performance Standards BB93: 2014  applies to new or substantially refurbished schools. Acoustic conditions and noise are important factors in a school environment. See the Impact of School Environments: A literature review  and The Effects of Noise on Children at School.  The Equality Act 2010  requires schools to implement an accessibility strategy for the purpose of improving the physical environment, increasing participation and improving access to information for pupils with disabilities and special educational needs. The School Premises Regulations (1) and Independent School Standards (2) cover nursery, community, community special, foundation, foundation special and voluntary schools and pupil referral units. The respective wording of each relevant document is:

• (1) SPRs Reg. 7 – The acoustic conditions and sound insulation of each room or other space must be suitable, having regard to the nature of the activities which normally take place therein.

• (2) ISS Reg. 23.D – The standard in this paragraph is met if the proprietor ensures that the acoustic conditions and sound insulation of each room or other space are suitable, having regard to the nature of the activities which normally take place therein.

The Department for Education (DfE) issued non-statutory guidance in May 2013 that explained,

'In a school with a good acoustic environment, people will experience:

good sound quality – enabling people to hear clearly, understand and concentrate on whatever activity they are involved in;

minimal disturbance from unwanted noise (such as from activities in adjacent areas, teaching equipment, ventilation fans or road traffic).

In classrooms, class bases and other areas used for teaching, this will allow teachers to communicate without straining their voices. In some types of spaces, such as music rooms, recording studios, open-plan areas and rooms where pupils with hearing impairment are taught, there are additional requirements that may require higher acoustic standards than those for normal class bases.'

Building Bulletin 93: Acoustic Design of Schools - Performance Standards 2014 is intended for designers and building control bodies. It gives the performance targets for compliance with Requirement E4 of the Building Regulations on School Acoustics that 'each room or other space in a school building shall be designed and constructed in such a way that it has the acoustic conditions and the insulation against disturbance by noise appropriate to its intended use'.

The DfE published the updated version of Building Bulletin 93, Acoustic Design of Schools in December 2014. The review was influenced by the Priority Schools Building Programme (PSPB)  acoustic standards. The Priority School Building programme (PSBP) was a centrally managed programme set up to address the condition needs of schools requiring urgent repair. Through the PSBP, 261 schools were rebuilt or substantially refurbished to have their condition needs met. The new acoustic performance standards ensure all new or substantially refurbished schools in England comply with the acoustic requirements of the following regulations:

• The Building Regulations

• The School Premises Regulations 2012

• The Independent Schools Standards 2010, updated 2014.

The aim of the performance standards is to provide acoustic conditions in schools that facilitate clear communication of speech between teacher and student and between students and do not interfere with study activities.

There are now clear minimum standards for refurbished buildings and these new BB93 values are the minimum requirements for Building Regulations approval. The design of accommodation for pupils with special hearing, speech, language and communication needs often requires the use of alternative performance standards to suit the local approach to inclusion and the particular types of special needs. The revised BB93 states that 'the criteria given in the tables for spaces intended specifically for these pupils should be a starting point' and that 'an acoustician should always decide, in consultation with the school and an audiologist where necessary, on a case by case basis, what the appropriate acoustic standards are; and should produce Alternative Performance Standards to suit the particular needs of the pupils and the intended use of the facilities.' All school buildings are subject to detailed design checks and on-site inspections by building control bodies. BB93 also gives guidance on how to meet the acoustic requirement of the School Premises Regulations and the Independent School Standards.

The Institute of Acoustics and the Association of Noise Consultants have jointly published a new design guide for the acoustics of schools (2015). The 110-page document, entitled Acoustics of schools: a design guide, is designed to accompany the revised performance standards for the acoustic design of schools published by the Department for Education in December 2014 It is a revision of the guidance previously published in 2003 as Sections 2 to 7 of Building Bulletin 93: Acoustic Design of Schools.

It is now possible for professionals to establish, with a fair degree of accuracy, the acoustic characteristics of all its learning spaces using a variety of apps that are now available for both iOS and Android Smartphone operating systems. However, depending on their purpose, for example, reporting, SEN Tribunal evidence or design, measurements will need to be taken with a suitable Class 1 or Class 2 sound level meter. Once the characteristics are established, the school is then in a good position to decide what further action could be taken to help overcome any significant problems. It is important to involve a suitably qualified acoustician to advise on installing appropriate acoustic and sound insulation materials. Classroom audio distribution (CAD) or soundfield systems may help. Details can be found in Smaldino, J. and Ostergren, D. (2012) Classroom Acoustic Measurements, listed below under Further References.

Further References

Standards: ‘Building Bulletin 93’(2014)

Guidance: ‘Acoustics, lighting and ventilation in schools’ (2014) Government Education Funding Agency

Example of acoustic treatment

NDCS Resources and Advice on Acoustics/ NDCS Quality Mark on Acoustics

‘Do Scotland’s Schools Sound Good?’ Report by NDCS (2011)

Smaldino, J.and Ostergren, D. (2012) ‘Classroom Acoustic Measurements’ in Smaldino, J. and Flexer, C.(ed.) (2012) Handbook of Acoustic Accessibility: Best Practices for Listening, Learning and Literacy in the Classroom. New York: Thieme Medical Publishers (ISBN 978-1-60406-765-1)

Adrian James has produced a 10-step guide to acoustic design, which gives suggestions on ways of producing a good acoustic environment.

The addition of curtains, blinds, carpeting, drapes, soft furnishings etc can all help towards improving the reverberation times in a classroom.

There are also a range of commercial materials which are available can be purchased and fitted to help improve the clarity of speech signals in the classroom. For example - acoustic ceiling and wall tiles, acoustic wall panels and tiles.

Below are two links that can each provide significant research evidence and advice on the types and varieties of manufactured materials that can be used to address different acoustic problems.

• RIBA product selector

• Ecophon 

BATOD Foundation held two study days - the 2011 one was sponsored by the Suppliers of Soundfield Systems and the 2012 study day celebrated the Ewing Foundation 60th birthday. Each event was open to all professionals working in deaf education; SENCOs and teachers in mainstream schools; architects and planners working with new and old buildings especially where hearing-impaired children and young people are educated. The list included school governors and parents and anyone who wanted to learn more about how to improve the listening and learning conditions in schools and secure excellent speech intelligibility to optimise pupils' learning.

All the presentations, listed below, can be accessed on the BATOD Foundation website, or through the links below.

What are they hearing? Wendy McCracken (Senior Lecturer, Manchester University) ilearn link

Benefiting everyone in school Roger Turner (Educational Consultant)

Gathering evidence in support of improving the acoustic conditions of classrooms Matthew Bysouth (Educational Audiologist)

Acoustic Treatment in the rooms we have Shane Cryer (Ecophon)

The Essex Project David Canning (Group Manager: Sensory Newham)

FM and SFS Liz Reed-Beadle and John Popplestone (FM Working Group)

Identifying funding Brian Gale NDCS

Impact case study - Soundfield in Hertfordshire Honor Andersen

What are they hearing?  Professor Wendy McCracken (Manchester Univ)

Benefitting everyone in school  Roger Turner (Educational Consultant)

Gathering evidence in support of improving the acoustic conditions of classrooms  Tim Wilding (Manchester Univ)

Acoustic treatment in the rooms we have Bob Moon (Ecophon)

Evaluation of fm and SFS Oticon Foundation  Anne Roberts + FM team

LENA (Language ENvironment Analysis)  Imran Mulla (Ear Foundation and Manchester Univ)

Collective research, knowledge and practice of BATOD members and others interested and involved in all areas of improving education for the deaf worldwide. This advice is generally applicable to providing good listening conditions in all learning environments.

The collected information and advice is intended to encourage and provide evidence for the provision of good listening conditions in learning environments for ALL learners and especially for children with hearing and communication needs.

Deafness affects children's access to education all over the world.

We welcome case studies of what works elsewhere. Please send these to exec@batod.org.uk