Classroom Acoustics What Are Texas Architects Saying

February 2011

Sandra B. King, AuD, CCC-A

The topic of classroom acoustics has been studied for several decades, and the importance of providing students with acoustically good classrooms has been increasingly recognized around the nation. Movements like the Collaborative for High Performance Schools (CHPS) and professional societies such as ASHA and the Acoustical Society of America (ASA) have attempted to educate audiologists and the public about a national standard and policy that would benefit all children receiving instruction in classrooms. Similar to the start of another universal program (newborn hearing screening) and another accessibility guideline (teletypewriters [TTYs] for hard of hearing telephone users), the classroom acoustics initiative has had its proponents and opponents. It is hoped that collaboration with all stakeholders will increase the awareness and motivation needed to get leaders who are involved in school building to provide children with quiet classrooms that meet a national standard of performance. The ultimate success of a national classroom acoustics standard will depend on how well the recommendations it sets forth are followed. The standard, which has been approved by the American National Standards Institute (ANSI), is currently known as ANSI/ASA S12.60-2010/Part 1 American National Standard Acoustical Performance Criteria, Design Requirements, and Guidelines for Schools—Part 1: Permanent Schools; the standard is offered as a free download through the ASA.

As a capstone project [PDF], 64 architects in Texas responsible for school design were surveyed about their knowledge of acoustical performance criteria for the classroom, the practices they employed to address acoustics in the design and renovation phases, and their attitudes regarding the earlier published version of the ANSI standard (ANSI S12.60-2002). Comments from the architects are presented below.

What is at stake in the classroom?

Acoustic barriers to communication in the classroom are disruptive to learning, affecting speech perception, student behavior, and educational outcomes for students. Acoustic barriers in classrooms include excessive background noise and reverberation. Background noise can originate from internal sources (heating and air conditioning, plumbing, electrical, or other mechanical devices) or external sources (vehicles outside or noise coming from spaces adjacent to the classroom). Reverberation is sound that persists in an enclosed space due to reflecting off, rather than being absorbed by, surfaces within the room.

Acoustic barriers affect everyone's auditory perception ability. The most significant negative effect of poor classroom acoustics is on children with hearing loss, auditory processing disorders, or learning disabilities, as well as students learning English as a second language. Children spend around 45% of their classroom time listening to instruction from their teacher, yet there is no assurance that the teacher's voice is adequately heard.

Who oversees and enforces classroom standards?

The U.S. Access Board is an independent federal agency working toward accessibility for everyone. The board develops and maintains design criteria for building environments, such as classrooms, among its activities. It also provides technical assistance and training on these requirements and on accessible design. The board enforces accessibility standards that cover federally funded facilities through the Department of Justice. To facilitate compliance, the board works with building code developers and standard-setting groups such as ANSI.

The board, however, cannot require school districts to comply with the national standard for classroom acoustics at this time because acoustic performance criteria for a classroom are not referenced in the Architectural Barriers Act. This voluntary standard has been adopted into building code by some but not all states and school districts.

Are Texas architects confident about designing classrooms with good acoustics?

The architects approached the survey expressing varying levels of confidence in answering questions on acoustics. The architects surveyed had been designing classrooms for 2–44 years, with about 22 years of experience on average. Architects who appeared more confident discussing acoustics were newer to the field, from larger firms, or owners of firms. It was interesting to learn how the architects approached designing a classroom with good acoustics when they had limited control over design choices, such as when school districts had different priorities on where to spend financial resources. Some school districts were interested in spending money on new athletic venues rather than on following architectural suggestions to improve buildings for academics. When acoustics were addressed in planning in the district's design phase, it was often only for performance areas (band rooms or auditoriums) or challenging areas (cafeterias or gymnasiums). Some architects, except for a few following Leadership in Energy and Environmental Design (LEED) or CHPs guidelines, did not see classrooms as a priority for acoustics and never checked the rooms to see whether they were within guidelines. It was disappointing to hear one architect state that he preferred to be more of a generalist and would delegate acoustics to an acoustic engineer. And surprisingly, another stated that acoustics was not an exact science!

The following are collective responses from the 64 educational architects across the state of Texas regarding classroom acoustics:

  • Practically all architects were aware that classroom acoustics could affect a child's perception of speech, language development, or reading ability.
  • Less than one third understood that a normal hearing adult was not able to accurately judge whether classroom acoustics were appropriate for a child developing speech.
  • One third of the architects were aware of the national ANSI standard for classroom acoustics. Several asked for the name of the standard to be repeated so they could make note of it.
  • About one fifth said they referred to the standard while designing schools. A few others referred to LEED criteria that resemble but don't meet the national standards criteria and don't include verification measures.
  • One architect commented that he made use of a sound level meter to measure noise within school buildings.
  • Generally, if an acoustic consultant was employed it was for performance areas such as auditoriums and band rooms or large rooms such as gymnasiums and cafeterias. Only four of the architects ever requested that the acoustic performance of a classroom be measured.
  • One half of the architects reported their training in acoustic design for classrooms was obtained through practical work experience, one third relied on in-services offered by manufacturers, and a couple chose classroom acoustics as a topic of study for continuing education.
  • More than 80% reported that they relied on published sound transmission ratings of materials to prevent noise travel between adjacent spaces.
  • More than two thirds of the architects had responded to school district complaints of unwanted noise due to reverberation; building service design; poor building quality; cutting corners on building materials, which resulted in noise transfer; material choices made for easier maintenance, which affected acoustics; and older buildings that were not up to current codes.
  • Some of the architects turned to "reinforcement without construction," which means the use of sound-field amplification in the classroom without considering reduction of reverberation or current noise problems, such as heating and ventilation noise, within the room.
  • Only four of the architects ever verified that classroom acoustics were appropriate. Those architects who verified said that only some of the seating positions allowed children to hear the teacher's voice adequately.
  • When asked whether a portion of Federal money provided to schools should be used to check and fix classroom acoustics, more than half said yes. Supporters of this position believed it would be beneficial for academics in general and that federal funding would be necessary for more depressed regions of Texas unable to fund this on their own. The architects in support of this federal funding said that the funds would have to be specified for classroom acoustics. The architects said that they did not make decisions on how to spend money in the school, but rather districts made the final decision. The architects who were in opposition to federal resources felt that general contractors and building services professionals or districts needed to be held responsible for poor building practices that affected acoustic conditions.
  • Three fourths of the architects were not opposed to the ANSI standard becoming the building code and agreed that acoustics were important. Some architects questioned how a code would be enforced. Architects who were opposed to the standard stated that there should be less government intervention in building design and gave examples of how the code system was in conflict with itself.

Why should we be so concerned about classroom acoustics?

Our country is seeing increasing numbers of immigrant children with limited English proficiency entering the public school system. Children are being identified with hearing impairments at very young ages. Many kids who use hearing aids, cochlear implants, and auditory-oral communication are entering mainstream classrooms. All students, especially those with disabilities or other challenges, need good classroom acoustics.

Are classroom acoustics better when architects design classrooms?

The Texas architects' comments and opinions revealed that they were concerned with acoustics in their buildings. They held school districts accountable for what they as architects were able to accomplish in planning and design based on compliance with the Americans with Disabilities Act (ADA) accessibility guidelines and Texas Education Agency rules, as well as the district's budget and choices made by the district for design preference and environmental maintenance.

In the bidding process for school (re)design, the district assesses what needs to be done and how many dollars are available. Builders who can meet the district's budget offer a proposal, the winning bid is selected and the designing begins. School districts are constantly trying to stretch bond dollars, while others do not even have them. For school districts with budget constraints, replacing leaky roofs and other necessary repairs take precedence. Others are trying to get an old school into compliance with current ADA accessibility guidelines. Still others choose to use extra funding for auditoriums and stadiums rather than on improving classroom environments for educational achievement.

How can audiologists help to improve classroom acoustics?

Communicate. Be familiar with the ANSI standard and the ADA accessibility guidelines or other standards used in your state. Get this information out to your school district at school board meetings or to a facility planner for the district. Involve teachers or parents who also have concerns. ASHA has a new brochure called "The Noisy Classroom" that is written for non-audiologists and is perfect for Parent-Teacher Association presentations.

Some school districts are following guidelines from organizations like CHPS or LEED to earn a certification for their buildings. Some of the criteria in these guidelines attempt to emulate the ANSI national standard but fall short of meeting it, and these differences should be made apparent to districts, hopefully before planning starts.

Verify. Evidence can speak for itself. The ANSI national standard for classroom acoustics includes conformance testing in its guidelines. While testing is not required, it does give evidence that the criteria are being met, and it must be done for points earned on the Texas CHPS Designed Scorecard to earn the CHPS certification.

Annex A of the ANSI national standard describes the procedures used in conformance testing, and audiologists should be familiar with how to perform the background noise level measurements. In addition to conformance testing, speech-language pathologists and audiologists could gather information by objective measures of student auditory perception and subjective behavioral observations made by the teacher.

Audiologists should introduce themselves to school administrators and offer to educate them as well as teachers and parents on appropriate classroom acoustics. Simple sound level measures without the need to call in a consultant might help identify acoustic problems in a less costly and efficient manner.

Unless a school district voluntarily measures classroom acoustics and records noise and reverberation data, there is no evidence that classrooms meet the ANSI criteria demonstrated to be necessary for children to perceive speech.

Educate. There are ways to improve speech delivery in the classroom. Consult with districts, school speech-language pathologists, and teachers regarding the use of sound-field amplification (with an explanation on reverberation), multimedia devices, closed-captioning, variable seating arrangements, and room décor. Educate them regarding frequency spectrum changes when raising the voice and about voice disorders.

The best time to collaborate with districts is when they are considering building a new school or taking on renovations. Educational architects and school administrators would rather get classroom acoustics right the first time than fix problems later on with costly remedies. Perhaps if audiologists initiate education programs for local districts that include information on the importance of good acoustics for learning, improving noisy classrooms, sampling noise levels, and reverberation in current classrooms, we will soon see better classroom learning environments.

About the Author

Sandra B. King is an audiologist living in Texas and has two children enrolled in elementary school. She completed her audiology doctorate degree in May 2010 through an off-campus program offered by Central Michigan University.

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