CAETS Noise Control Technology Committee (NCTC)

CAETS Noise Control Technology Committee

Quieter Cities of the Future  May 2014

Road traffic noise is a worldwide problem. It is the major noise source in the cities. Immission goals, mainly in the form of guideline values, were already formulated in many countries in the 1960s. In contrast to many other environmental areas, these values have not been strengthened since then.
When first formulated, the goals were based on criteria for speech interference and on what was known concerning influence on sleep and annoyance. Now, the scientific basis for health-based targets has become much stronger.
It is a demanding task to decrease the adverse health effects of traffic noise. There is no single technological fix available either on the source side or on the immission side. No organization by itself can do much to improve the situation. A conserted action by several involved bodies is needed but is non-existent today.
The purpose of the CAETS Forum in 2013 was to clarify the effectiveness of present methods and policies used by each separate body and to investigate the possibilities to achieve a substantial change. The forum was unique in bringing together noise control experts covering the whole chain from source to receiver including the health effects of the resulting immissions. Participation was by invitation only. The panelists were given specific questions to answer within their respective fields of knowledge. The panelists as well as other participants were specialists from the automotive industry, academia, public authorities, and consultants.
The forum was broader than the title indicates as it also covers measures on the immission side. The road traffic noise problems cannot get reasonable solutions only through emission reductions even with foreseeable best technology. But it was also clear, that present methods to measure and describe the emissions are neither sufficient nor adequate from an immission stand point.
In this report the most important findings from the forum are given. Based on these findings, conclusions were drawn on what is needed and what can and should be done in terms of policy to substantially reduce the adverse health effects of traffic noise.

Tor Kihlman                                        Wolfgang Kropp                              William W. Lang
Chalmers University                       Chalmers University                      Noise Control Foundation
Gothenburg, Sweden                    Gothenburg, Sweden                   of Technology of Technology
                                                                                                                                Poughkeepsie, NY, USA

The health effects of traffic noise are severe and constitute a threat to public health.  All presentations and discussions on which the report is based are included in the SOURCE BOOK, ref [1], which is posted on the website of Chalmers University of Technology, Applied Acoustics:


ACTIVITY REPORT: 2012 – 2013

At the 2010 CAETS Council meeting in Copenhagen, the Noise Control Technology Committee (NCTC) was tasked to provide active science-based support for noise control policymakers on technological options for a quieter world. The activities of the committee during 2010-2011 were presented at the last meeting of the Council in Zurich. The work of the committee during the past year has concentrated on:

·       Further defining cooperative work between CAETS and the International Institute of Noise Control Engineering (I-INCE) according to the Memorandum of Understanding (MoU) between the two organizations of 2010 October.

·       Giving advice to policymakers on issues related to noise control. Much of this has concerned the ongoing process within the European Union (EU) to strengthen the noise limits for road vehicles.

 CAETS and I-INCE Cooperation

I-INCE has established a committee representing I-INCE Member Societies to carry out the cooperative work between CAETS and I-INCE, according to the MoU, by serving as a backup for the NCTC. As the backup the I-INCE committee supports the mission and scope of the NCTC in all respects and aids the NCTC by providing assistance, perspective, and specialists in many technical sub-specialties. The NCTC’s scope is to focus on engineering control of the world’s dominant noise sources and to improve the quality of life and public health and welfare by promoting the reduction of noise emitted by the principal noise sources in the community environment and at the workplace. This is to be accomplished by disseminating relevant information to decision makers, manufacturers, consumers, and the public. Industry has the technical competence or knows what needs to be developed if requirements are strengthened. 

 The NCTC offers a new perspective on the noise policy issue. CAETS, in its independent role representing the world’s leading engineering academies, is able to step back and study a technical issue from a fresh viewpoint. The stakeholders in the noise issue are numerous—legislatures, government agencies, local authorities, manufacturers, trade associations, non-governmental organizations, advocacy groups, the public, and others. CAETS is independent of, and not beholden to, any of the stakeholders in the noise issue except, possibly, the public which the academies are implicitly obligated to serve. The role of the NCTC is that of an impartial expert witness without affiliation or bias.

 The NCTC objective is to assist policymakers in improving national and international requirements by emphasizing the need for careful consideration of the noise emissions of dominant noise sources and by providing unbiased information. What is needed are well-informed policymakers who can challenge industry, set up stringent noise limits, and stimulate market forces through “buy-quiet” programs.

 Ongoing Work on New EU Noise Limits for Road Vehicles

Progress towards quieter road vehicles is slow mainly because of the large number of conflicting interests and the very special role of the car in society. The health effects of road traffic noise have not been understood or appreciated by those who are responsible for the noise emissions from the traffic. 

 The technical requirements on road vehicles are the responsibility of the United Nations Economic Commission for Europe’s Working Party 29 (WP29). WP29 is the “World Forum for Harmonization of Vehicle Regulations” tasked to create a uniform set of regulations for guiding vehicle design to facilitate international trade. WP29 regulations on vehicle noise limits become mandatory when adopted by national legislation worldwide. 

 WP29’s work is based on two agreements—the 1958 agreement to which 58 countries are signatories with the USA a notable exception and the 1998 agreement on which the USA is a signatory. The 1958 agreement operates on the principle of type approval and reciprocal recognition. The 1998 agreement establishes technical performance requirements.

There are current UNECE regulations applying to the noise of passenger cars. They are R51-Noise Emissions and R771-Rolling Sound Emissions of Tires for which amendments are currently being developed.

The GRB is a technical committee for drafting regulations covering vehicle noise emissions whose regulatory proposals are submitted to WP29 for approval. GRB meetings are held twice a year (September and February) in Geneva. More than seventy experts usually participate in these meetings of the GRB in Geneva. The GRB consists of a group of experts who “… conduct research and analysis …” to develop noise requirements for vehicles. Decisions on draft resolutions are taken by government representatives by vote at WP29 meetings. 

The GRB is open to governmental experts from any UN member country and to representatives of accredited NGOs. To participate in WP29 and GRB meetings, an NGO must first be accredited in a consultative status to the Economic and Social Council of the UN (ECOSOC).  Recent research in Europe points to the serious health effects of traffic noise, including death. This work has not been accepted by the GRB due to the methods used and assumptions made.

The progress towards quieter traffic in Europe has been extremely slow. The last time the regulations on vehicles were sharpened was 20 years ago, but the net effects were marginal. Traffic noise has, for many years, been the subject of political interest within the EU. The Environmental Noise Directive of 2002 has led to a program of noise mapping within the EU member states which has clarified how vast the problem is. The health effects have further been clarified by two reports from World Health Organization/Europe and with the data from the noise mapping it is estimated that the number of premature deaths from traffic noise is substantial and may be of the same order of magnitude as the number of persons killed in traffic accidents annually. It is clear that the emissions have to be reduced in order to make real progress on decreasing the severe health effects. The progress in WP29 has been slow and, therefore, work on the possibilities for sharper noise limits has been slowed for the European Commission.

 The European Commission has, on the basis of commissioned reports from a Dutch research organization, TNO, presented a proposal for new noise limits with measurements according to a new test method worked out between GRB and the International Organization for Standardization. This proposal has been debated in the European Parliament and a decision is expected in 2013 from the European Council. Lobbying is intensive.  It is assumed that once EU has made a decision, this will lead to a similar decision by WP29 which is necessary considering the above-mentioned agreements. It is anticipated that progress towards quieter vehicles will be very limited if the proposed new regulation is promulgated.

 NCTC has followed the work and sent letters to EU officials and politicians. To the NCTC it appears that the GRB is taking limited account of the health effects of traffic noise and of its responsibility to minimize such effects. Our opinion is that the new test method is inadequate to decrease these health effects. However, it is the best that can be done at present and the ongoing process within the EU should be supported. When this is finished in 2013 or 2014, we should renew our efforts with GRB. 


The following activities have been completed or are in progress since the last activity report:

·       2012 March 20: CAETS NCTC chair and secretary signed a letter entitled “Experts Support for Stricter Vehicle Noise Emissions Standards” addressed to Mr. Ouzky, MEP, Rapporteur for Environment. It concluded:

    “We the undersigned are convinced, on the basis of scientific evidence, that the monetary benefits of quieter traffic by far outweigh the costs of quieter vehicles to society. This is already proven by market availability of vehicles that would satisfy even the most stringent future demands. If all vehicles would meet the level of today’s best current technologies available, the environmental noise problem caused by road traffic would be greatly reduced. The technology for quieter vehicles is sufficiently well known to set substantially stricter noise limits.

    “Vehicle noise emissions limits have remained unchanged since 1992, with the result that the noise burden on Europeans has continued to increase. Vehicle manufacturers have regrettably not been encouraged by regulation to reduce noise, and we strongly support the Commission’s initiative to finally take action with several steps of increasingly stringent limit values to be introduced over the coming years. The delay caused by the German proposal is therefore rejected.

    “We the undersigned urge you as rapporteur, and your fellow Members of the European Parliament, to take the above into consideration when considering the legislation on vehicle noise emissions.”

 ·       2012 March 21:  The NCTC position, presented by Transport and Environment (Brussels) at the European Parliament meeting on “Addressing the Problem of Noise Pollution in Road Transport” stated that the current proposed directive is inadequate. 

 ·       2012 June 1: On behalf of the NCTC CAETS applied for Consultative Status in UN ECOSOC. This includes UNECE WP29 and GRB. The application was accepted and approval is expected before the end of 2013.  Consultative status will:

o   Make it unnecessary to interact with government representatives to obtain a seat at the GRB table,

o   Possibly provide opportunities to introduce constructive proposals without review prior to GRB meetings,

o   Allow NCTC to concentrate on technical issues, and

o   Establish the NCTC and the CAETS organization as authoritative voices in the policymaking arena.

 ·       2012 August 20:  The NCTC chair presented an invited paper on global noise policy at the INTER-NOISE Congress in New York City entitledNoise policy - Integration with climate and natural resource policies.

·       2012 August 30:  The NCTC chair presented a paper in the CAETS Symposium in Zurich entitled “Noise Mitigation:  Possibility for Quieter Cities in Europe.”

·       2012 August 31:  The NCTC chair gave an activity report at the CAETS Council meeting in Zurich.

·       2012 October 3:  The NCTC responded to “Consultation on the Implementation Report of the Environmental Noise Directive (END) and on the EU Noise Policy.”  (CAETS NCTC reply to EU Consultation) 

·       2012 October 18: The NCTC chair was informed that “Each year over 245,000 in the EU are affected by cardio-vascular diseases that can be traced to traffic noise” . . . and “almost 50,000 suffer a lethal heart attack.” The NCTC decides to examine the epidemiological basis for this statement.

·       2012 October 24:  Through its MoU with the International Institute of Noise Control Engineering, the NCTC provided input and funding to a roundtable entitled Noisy Motorcycles: An Environmental Quality-of-life Issuein Washington, DC, USA.

 The following activity is being planned by the NCTC: 

·       2013 September 19: An NCTC forum on “Lessening the Severe Health Effects of Traffic Noise in Cities by Reducing Emissions” is being planned. This subject is of keen interest within the EU and to governments around the world. In partnership with I-INCE, the NCTC is organizing the forum to be held in Innsbruck.

·       2014 February: As CAETS is now recognized as an organization with Consultative Status by the United Nations ECOSOC, the NCTC will have a chair at the table to present the NCTC position on the health effects of road traffic noise to the WP29 GRB organization at its meeting in Geneva.


The CAETS NCTC continues to focus its major activities on working to reduce road traffic noise in Europe. The success of this project will make a difference in the development of global noise policies, but its success depends on extensive support from the noise control engineering community. Only with that support can a balance with the lobbyists from industry be established. The noise level limits on the world’s dominant noise sources must be reduced, and the metrics and measurement methods must be clearly defined. When lower noise emission limits are proposed, it is important that excessively long lead times for their implementation not be permitted.

 While the noise emission requirements on major noise sources need to be tightened, legislation is not the only way for this to be accomplished. The public must be educated, and market forces need to be developed and strengthened so that low-noise products are demanded by purchasers.

The gap between the current noise levels of the major noise sources and what is needed to eliminate the noise problem caused by these sources is large, often on the order of 20 dB. There is a long way to go to solve the world’s noise problems.  For some noise sources existing technology is currently available that will produce substantial reductions in noise emissions. But for other sources much research and development is needed to produce significant reductions in the noise emissions and may need several decades of devoted work to accomplish this.

Finally, it must be emphasized that each decibel of noise source reduction is valuable. Even a 5 decibel reduction in the noise emission of a major noise source would make a significant difference. A 5 decibel reduction is possible for many of today’s products by using the best available technology. The public and the policymakers must be informed of the existence of this technology as the high noise levels of many current products are not only unwanted but they are also unnecessary.

 Tor Kihlman, Chair, and William W. Lang, Secretary

CAETS Noise Control Technology Committee



      Tor Kihlman, IVA, Sweden                                


William W. Lang, NAE, USA                             



Australian Academy of Technological Sciences & Engineering

Louis Challis, ATSE                                          

Adrienne E. Clarke, ATSE                                


Canadian Academy of Engineering

Tony Embleton, NAE                                        

W. G. (Fred) Habashi, CAE                              

L. John Leggat, CAE                                         

Jean Nicolas, CAE                                            


Chinese Academy of Sciences

Jing (Jerry) Tian, CAS                                       


Danish Academy of Technical Sciences

Per V. Bruel, ATV                                              

Per Hartlev, ATV                                               


National Academy of Technologies of France

Genevieve M. Comte-Bellot, NATF                   


Indian National Academy of Engineering

M. L. Munjal, INAE                                            


Engineering Academy of Japan

Hideki Tachibana, EAJ                                      

Ichiro Yamada. EAJ                                          

Kohei Yamamoto, EAJ                                      


National Academy of Engineering of Korea

Jae-Eung Oh, NAEK                                         


Netherlands Academy of Technology and Innovation

Niek Ketting, AcTI-nl                                         


Royal Swedish Academy of Engineering Sciences

Tor Kihlman, IVA, Committee Chair                  


Royal Academy of Engineering, UK

Dame Ann Dowling, FREng                              

Philip Nelson, FREng                                        


National Academy of Engineering, USA

William W. Lang, NAE, Committee Secretary   

Richard H. Lyon, NAE                                       

George C. Maling, NAE                                    


An Invitation to Participate

Twelve CAETS academies have members on the CAETS Noise Control Technology Committee (NCTC). Other CAETS academies are welcome to participate in the work of the NCTC and are invited to nominate one or more of their members to join the committee.

The CAETS committee’s scope is to focus on engineering control of the world’s dominant noise sources. Engineering control is accomplished by design to reduce the noise power emitted by the source and requires detailed understanding of the mechanisms for the generation of such noise power. Engineering control may also be accomplished with “add-on” treatments such as lined ducts and mufflers. 

Members of the committee include experts in noise control engineering as well as academy members trained in other disciplines who have an interest in the noise issue. For more information on committee activities or committee membership, contact the NCTC Chair or Secretary.

 Tor Kihlman, Chair,

William W. Lang, Secretary,

CAETS Noise Control Technology Committee




Activity Report for December 2012 - August 2012

 2012 October 3:  NCTC responds to “Consultation on the Implementation Report of the Environmental Noise Directive (END) and on the EU Noise Policy.”  (120903 CAETS NCTC reply to EU Consultation)  (Attached)

2012 August 31:  NCTC Chair gives activity report to CAETS Council. (Attached)

2012 August 30:  NCTC Chair gives paper in CAETS Symposium entitled “Noise Mitigation:  Possibility for Quieter Cities in Europe” (Attached)

2012 August 20:  NCTC Chair presents invited paper at INTER-NOISE Congress in New York City onNoise policy - Integration with climate and natural resource policies(Attached)

July 2012 – December 2011

  2012 June 1: NCTC through CAETS applied for Consultative Status in UN ECOSOC. This includes UNECE WP-29 and GRB. Application accepted and in process by UN. (Attached)

 2012 March 21:  Presented through T&E CAETS NCTC position at European Parliament Brussels meeting on “Addressing the Problem of Noise Pollution in Road Transport” stating that current proposed directive is inadequate. (Attached)

 2012 March 20: CAETS NCTC chair and secretary signed a letter entitled “Experts Support for Stricter Vehicle Noise Emissions Standards” addressed to Mr. Ouzky, MEP, Rapporteur for Environment EP. (Attached)

 2012 February 15: Submitted comments on draft directive on recreational craft and personal watercraft addressed to Vincenzo Matano, MEP. (Attached)

 2012 February 8: Participation at GRB Geneva meeting postponed pending action to enable NCTC to have a seat at the table. (See entry for 2012 June 1.)

 Activities of the NCTC

November 2011 – October 2010

 2011 November 29: Letter to EC vice presidents recommending stricter noise limit values on vehicles for European roads

2011 November 23:  Invited presentation at European Parliament workshop in Brussels on “Paving the Way for a Quieter Europe”

2011 September 12: Presentation in Tokyo to the Japanese Ministry of Environment

2011 September 4: Opening plenary presentation at INTER-NOISE 2011 Congress in Osaka, Japan

2011 July 5-6: Symposium on “Inducing ‘Buy-Quiet’ Purchasing Attitudes” in Paris

2011 June 05: Again recommended stricter noise limit values on vehicles for European roads

2011 May 12: Federal Agency Workshop on “Technology for a Quieter America” in Washington

2011 May 02: Recommended stricter noise limit values on vehicles for European roads

2011 March 11: Participation in experts’ support for stricter EU vehicle noise emission standards

2011 February 10: Response to Australian Senate Committee Inquiry on Wind Turbine Noise

2010 December 15: 6th national conference on “The Quality of the Sound Environment” in Paris

2010 October 29: EC workshop on outdoor equipment noise in Brussels


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