2001 October 29-31
THE INTERNATIONAL INSTITUTE OF NOISE CONTROL ENGINEERS' TECHNICAL INITIATIVE FOR SCHOOLROOM ACOUSTICS
Louis C. Sutherland, Consultant in Acoustics, 27803 Longhill Drive, Rancho Palos Verdes, CA 90725-3908, USA
David Lubman, Acoustical Consultant, 14301 Middletown Lane, Westminster, CA
Zerhan Karabiber, Yildiz Technical University, Faculty of Architecture, 80750, Besiktas, Istanbul, Turkey
A technical initiative titled "Noise and Reverberation Control for Schoolrooms" was approved by the International-INCE General Assembly at its meeting in December 1999. The initiative is intended to be an internationally coordinated program to assist participating nations with engineering issues associated with achieving satisfactory acoustics in learning spaces.
Because good acoustics is indispensable to verbal learning, it should be made an essential requirement for schools in all knowledge-based societies. The World Health Organization has identified the basic acoustical requirements for verbal learning spaces in its Guidelines for Community Noise, April 1999. Some nations are well along in meeting these requirements while others lack local guidelines or other resources. The worldwide acoustical design and noise control communities can offer valuable assistance to nations wanting to achieve good schoolroom acoustics. With support by representatives of various I-INCE member societies appointed to this Technical Study Group (TSG) # 4, chaired by the third author, the plan is to submit a draft report for review by the I-INCE General Assembly in Aug, 2002. The report is expected to provide practical guidance to school planners, designers, and code officials. The TSG, convened at the Internoise meeting at Nice, France in August 2000. has now grown to the membership of 19 representatives from 16 countries shown in Table 1. This paper summarizes highlights of some of the above work already accomplished and outlines some of the effort being planned by the US representatives to help accomplish the remaining objectives of the TSG.
Table 1 Membership of TSG # 4 as of Aug., 2001.
|Warwick Williams || Australia |
|Gerrit Vermeir|| Belgium |
| Murray Hodgson || Canada |
| Tomas Rozsival || Czech Republic |
| Michel Vallet || France |
| Agnes Pota || Hungary |
| Luigi Maffei || Italy |
| Toshiko Fukuchi || Japan |
| Sun Woo Kim || Korea |
| Philip J. Dickinson, Joanne Valentine || New Zealand |
| Ronny Klaeboe || Norway |
| Primoz Gaspan || Slovenia |
| Carsten Svensson || Sweden |
| Nese Akdas || Turkey |
| Bridget Shield || UK |
| David Lubman || USA-ASA |
| Lou Sutherland || USA-INCE |
| Zerhan Karabiber (Convener)|| Turkey |
NATIONAL STANDARDS OR GUIDELINES FOR CLASSROOM ACOUSTICS
In conformance with the plan developed at the first meeting, a summary of existing or soon-to-be available guidelines or standards for classroom acoustics from 8 different countries has been identified and partially assembled as shown below. In a final report, these national standards and guidelines will be tabulated in a summary of different performance criteria (e.g. - background noise levels and reverberation times) or design requirements for noise isolation between learning spaces and other spaces within a school.
- Australian / New Zealand Standard AS/NZS 2107:2000 Acoustics-Recommended design sound levels and reverberation times for building interiors
- France; La Qualité Acoustique des Lycées et Colleges / guide (1996) Ministere de l'Environnement.
- Italian Standard,
- Japan "A standard for acoustic environment in schoolroom" by Architectural Institute of Japan. Standard is about sound insulation, impact sound insulation and background noise.
- Swedish Standards (nearing final publication)
Turkish Noise Control Regulation
- UK, Guidelines for Environmental Design in Schools, Architects and Building Branch, Department for Education and Employment, First published 1997, Second Impression 2000
- Last year schools came within Building Regulations so there is now a legal requirement for schools to comply with guidelines,
- The current guidelines are being rewritten and a new book on acoustic design for schools is being written to accompany the guidelines,
- USA, ANSI S12.60-200X, Acoustical Performance Criteria, Design Requirements
and Guidelines for Schools, Final draft submitted to ASA/S12 in
Sept., 2001 for second ballot. Standard limits A-weighted background noise (1 hr Leq) to 35 dB for core (classroom) learning spaces, 40 dB for ancillary learning spaces such as cafeteria and gyms and 45 dB for other ancillary learning spaces, such as corridors if no formal instruction takes place. Reverberation times (500-2,000 Hz) for unoccupied, furnished core learning spaces is 0.6 sec. (< 10,000 cu.ft.) or 0.7 sec (10,000-20,000) cu. ft. Noise isolation of separating partitions varies from STC ratings of 45 to 60 depending on the type of source and receiving spaces. Extensive informative design guideline Annexes included.
- WHO, Guidelines for Community Noise
The substantial effort remaining for the TSG is identified in the following draft work plan set forth by the TSG convener.
Table 2. DRAFT TIMETABLE OF ACTIVITIES FOR I-INCE TSG #4, August 2001
COLLECTION OF PERTINENT REPORTS, LITERATURE and RESEARCH
Directly pertinent literature, consisting of numerous reports or papers from 10 different countries has been collected, and 8 current research studies on classroom acoustics from 3 different countries have been identified. Some of this information is identified in the following in abbreviated form. For the sake of brevity, no attempt is made here to provide details on the source for this information. This will, of course, be provided in a final report.
Reports and Literature
- Argentina - Experimental investigation of the acoustical characteristics of typical Argentinean classrooms, L. Ercoli. (Not a member of TSG)
- Australia - Noise level measurements at many different schools in Australia, NAL (National Acoustic Laboratories) Reports No 21, 32,33,34,54,55 and 128, W. Williams.
- France L'Acoustique des Locaux Scolaires (1989) Ministere de l'Education Natonale de Jeunesse et des Sports, 1989, Michel Vallet.
- Germany, Noise stress in classrooms, Symposium on Pyschological Acoustics, Oldendurg, 2000 (Report contains over 200 references), August Schick, et al.
- Italy, 1995 Italian Acoustical Association - Workshop on Noise and Schools. Presented results of measurements of noise levels and reverberation times inside 500 schoolrooms of 177 schools. (Proceedings in Italian), Luigi Maffei.
- United Kingdom, Classroom Acoustics Summary Report 1999 (A Research Project)
Heriot-Watt University, Edinburgh, D.J. Mackenzie and S.Airey.
- United States, Reports and papers including:
- Presentations at workshop on "eliminating acoustical barriers to learning in classrooms" (1997), Acoustical Society of America
- Papers at Classroom Acoustics Session, 17th ICA, Rome Italy; organised by D. Lubman
- Classroom acoustics - Success through partnering between a scientific society and the
U.S. government, Charles Schmid, Louis Thibault
- Simplifying design requirements for reverberation control in classrooms, Robert Apfel
- The impact of classroom acoustics on scholastic achievement, L C: Sutherland and D. Lubman
- Cost factor for improving acoustical comfort conditions of an existing classroom
Z. Karabiber, E. Çelik (Turkey)
- Good classroom acoustics is a good investment, D Lubman and L.C. Sutherland
- WHO, Guidelines for Community Noise, Dietrich Schwela
Research Studies, Completed, Current and Proposed
- Canada, List of research in classroom acoustics , covers information provided by B. Shields (UK), M. Jiggins (UK), N. Akdag (Turkey), M. Hodgson (Canada), Murray Hodgson
- Italy, Italian Universities presented proposal to Italian Minister of University and Research for two year research project on: Field analysis, physical models and numerical s imulation for the quality labelling of indoor environment - Educational buildings, Luigi Maffei.
- Turkey, Information on International Symposium on "Noise Control and Acoustics for Educational Buildings" 2000, Istanbul, Turkey., Nese Akda.
- United Kingdom
- Major project on effects of aircraft noise in schools - completed, Queen Mary College London, (Team led by Stephen Stansfeld ).
- RANCH project - European funding for Europe-wide study into effects of aircraft noise on children - same team plus Bernard Berry at NPL.
- Two year project, "The effects of noise on the attainments and cognitive performance of primary school children" - being completed, Bridget.Shield and J. Dockrell.
- New project (3 years) begun on effects of noise on hearing impaired children and on teachers ( voice problems, general health etc.). Use of amplification systems will also be studied, Bridget.Shield and Julie Dockrell.
- United States - Multiyear multidisciplinary study of environmental effects (including acoustics) on learning. Woods Research Institute. Will involve longitudinal studies in several classrooms.
SCHEDULE OF FUTURE ACTIVITY
Succeeding efforts of the TSG will include collation of this information in suitable summary text and/or tabular form. In addition, a key effort of the TSG will be categorize types and general construction of classrooms in order to determine different architectural, cultural and environmental properties of school classroom. This categorization will be of basic importance in preparation of guidelines for suitable technology for noise and reverberation control in classrooms and in investigation on cost-effective methods and materials that can be used in schoolrooms acoustics improvement. As outlined in a recent ICA paper , a rough estimate of the cost of acoustic treatment to control reverberation for a typical classroom in the U.S. is of the order of 0.5% of the estimated value of the improvement in education due to just a 3% improvement in word or sentence comprehension by a student. A more careful evaluation of such costs is clearly needed for this TSG. Hopefully, this can lead to construction of a template methodology or recommendation list for cost-effective acoustic treatment for both noise and reverberation control. Considering the wide range of economic factors in involved, such guidelines for cost-effective means to achieve this noise and reverberation control for the wide range of types of classroom construction encountered internationally will be a critical and challenging effort for the TSG.
A second formal meeting of the TSG was held on 27 August 2001 at The Hague during INTER-NOISE 2001 and an informal meeting was held during the 17th ICA Congress in Rome in the week of 3-7, Sept, 2001. Participation in the TSG by other countries, e.g. - Mexico, Argentina - to the study group, will be encouraged. Contacts with international entities including the World Health Organization, (WHO), International Standards Organization (ISO), United Nations (UNESCO) and the International (Building) Codes Council (ICC) and/or the International Building Code (IBC) will be initiated where possible and where appropriate for purposes of this TSG. Preliminary contacts with ISO have indicated that they have no plans at this time for development of a standard in classroom acoustics. However, the increasing interest in such a standard or guideline by many countries, as evident above, makes it entirely possible that an International Standard or Guideline (under the auspices of the IBC or ISO) could evolve out of, or be stimulated in part by, the activity of this TSG. Such an activity would likely extend well beyond the scope of this TSG but the possibility of the development a co-ordinated International Standard poses a challenge for an effective completion of the efforts of the I-INCE TSG.
I-INCE TSG #4 has initiated a study of noise and reverberation control in classrooms at a time when this topic is receiving increasing attention world-wide. While a considerable part of the work planned for the first year by I-INCE TSG #4 has been completed, there is still much do. Particularly challenging will be categorisation of school construction types and the development of a matrix of cost-effective noise and reverberation control methods appropriate for these various categories and types of construction and design for school classrooms.
 D Lubman and L.C. Sutherland, "Good classroom acoustics is a good investment", Proceedings, 17th ICA Congress, Rome Italy, Sept. 3-7, 2001.