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He said that there are over 1,800 kmof noise barriers in the United States.California far exceeds any other statein the construction of barriers which, inCalifornia, cost approximately 800,000USD per km. There are other disadvantagesbesides cost to noise barriers, and there isa significant amount of public concern. Hesaid that the current FHWA noise policyincludes the following:• The barrier installed must produce animprovement in noise levels of at least5 dB.• Porous pavements cannot be consideredas a noise-abatement measure.He pointed out that in light vehicles, tirenoise is prominent over a very wide rangeof speeds and that the character of thepavement may make quite a differencein the noise level—especially in the midfrequencyrange. Questions, he said, aboutthe use of porous pavements for noisereduction are “Does it last?” and “Does itwork for a mix of traffic?” He reviewed aporous pavement project on Route I-80 inCalifornia that involved a porous overlayput down in 1998. He showed data onnoise reduction over seven years. Theaverage was about 6 dB with dramaticreductions in noise levels for frequenciesgreater than about 1,000 Hz.He then described techniques formeasurement of tire/pavement noise.He described the close proximity (CPX)sound pressure procedure and the onboard,sound-intensity (SI) method, thelatter producing a signal-to-noise ratioabout 10 dB better than for sound pressuremeasurements exposed to airflow. Hediscussed the application of the intensitymethod to highway noise and said thatthere was good correlation when the SImethodis compared with controlled passbymeasurements.He then described a project on Route I-280near San Francisco where a 6 dB reductionwas obtained with a more porous,rubberized asphalt concrete. He said therewas a major project in Arizona where 185km of roadway were also paved with asimilar rubberized asphalt He said that8-12 dB of noise reduction was achieveddepending on distance from the roadway;and, for other sites, with different initialpavement types, he said that reductions of5-10 dB were achieved.He then turned from noise near interstatehighways to roads in communities wherehe said reductions of about 6 dB havebeen obtained. He discussed the use ofmodifying concrete pavement textures onbridges and showed improvements for avariety of conditions. He then reviewedbriefly the NITE project (Noise IntensityTesting in Europe) comparing data inCalifornia and Europe, and he said thatthere is good correspondence betweenthe quietest pavements in those two areas(See Noise/News International, 2005June, pages 46-53.—Ed.). He said thereis continuing work on porous pavementsincluding the parameters that control noise,sound absorption, and the effects on trucknoise (intensity information on some trucktires not providing as much noise reductionas passenger car tires). He describedpropagation experiments over porousand non-porous pavements, and test trackmeasurements to identify various kinds ofnoise sources on trucks. He concluded bysaying that recent studies have shown thatquieter pavements can be achieved and thatsound intensity has proved to be a usefultool for quantifying the source levels. Hesaid that the use of quieter pavementsshould be considered as an alternativeapproach to reducing traffic noise levels.The third plenary lecture was given onOctober 19 by James E. West of theJohns Hopkins University in Baltimore,Maryland, USA. The title of hispresentation was “Hospital Noise, its Rolein Patient Well-being and the Challengesfor Noise Control Engineers.” He dividedhis talk into three areas: existing literature,motivation, and measurements. He saidthat as early as 1859 Florence Nightingalerecognized thatunnecessarynoise in hospitalenvironments wasbad. He said therehave been somestudies all over theworld and in allsizes of hospitals,but there are nostudies reportingnoise controlapproaches. Thecurrent literaturedeals withadministrativecontrols; and theJames E. West ofJohns HopkinsUniversity presents thethird plenary lecture atNOISE-CON 05.papers are all by doctors, not acousticians.He said that the guidelines of the WorldHealth Organization (WHO) recommend amaximum level of 40 dBA and 30 dBA inrooms. The EPA levels document indicatesthat the L dnin hospital areas should notexceed 45 dBA. However, he said thatmeasured levels as much as 20-40 dBhigher than the suggested WHO value of40 dB have been reported, and that thereare other requirements (for example, ANSIS12.2) that contain recommended levelsthat are rarely met.He said that we should be motivated toreduce hospital noise levels for severalreasons:• It increases stress in the hospital staff.• There is evidence from animal teststhat noise levels can affect the speed ofwound healing.• Studies show that there is a longer stayin hospitals from cataract surgerieswhen the hospital stay has constructionnoise present.• Patients require more medication whensound levels are greater than 60 dB.He said there is not much data on theeffects of noise in hospitals on performanceof the staff but that studies beginning in1960 show that levels in hospitals areincreasing at the rate of 0.3 dB per year.None of these levels comply with WHO132 www.inceusa.org • www.noisenewsinternational.net • www.i-ince.org 2005 December
guidelines. He said that the night levelshave increased similar to the day levels butat a rate of about 0.4 dB per year.He said that we should care about noise levelsfor several other reasons: speech interference,recovery of patients, safety (noisemay create medical errors), and that somestaff members become prematurely deaf.He then turned to his own recentwork on hospital noise which hasbeen to characterize the noise and toexamine several noise issues includingarchitectural design, privacy, and speechcommunications. He showed manymeasurements in hospitals with typicallevels in the range of 65 dBA with veryfew breaks. He said that there are severalsources of noise in hospitals. Theseinclude pumps, warning signals, impulsivenoise from doors closing, instrumentalarms, individuals talking, and noisegenerated by various metal-to-metalcontacts. He said that hospitals need amuch better paging system than those thatexist in today’s hospitals. He said that themain goals in hospitals should be to reducenoise because:• There is distraction of the hospital staff.• There is a need to improvecommunications.either the Journal of the Acoustical Societyof America or Noise Control EngineeringJournal. A rough search by the editor forproceedings papers on hospital noise in2002 turned up very few papers. Most ofthe references in Dr. West’s paper are injournals related to medicine.)The searchable CD-ROM contains 198papers presented at the joint NOISE-CON05/ASA 150th meeting as well as 749papers from the NOISE-CON conferencesheld in 1996, 1997, 1998, 2000, 2001,2003, and 2004 as well as the papers fromthe Sound Quality Symposia held in 1998and 2002. All papers are PDF files.Several papers are taken from sessionsorganized by the Noise, ArchitecturalAcoustics and Structural AcousticsTechnical committees for this 150th ASAmeeting. The three plenary lectures relatedto noise and its impact on the environmentare included. Also included are papers inone or more organized sessions in the areasof aircraft noise, tire/pavement noise, andhospital noise. Other papers cover to noisematerials, mufflers and silencers, statisticalenergy analysis, acoustical facilities,product noise emissions, sound quality andperception, sound insulation of buildings,community noise, and environmental noisecriteria. A collection of papers on UnitedStates and international noise policy is alsoincluded on the CD-ROM.These papers are a valuable resource ofinformation on noise control engineeringthat will be of interest to researchers inthe academic community, governmentworkers, engineers, acoustical consultants,and students. The addition of the NOISE-CON 05 papers to the CD-ROM will bethe last. This CD-ROM will continueto be sold as a record of NOISE-CONconferences since 1996. The next NOISE-CON conference is scheduled for the fallof 2007 on the West Coast, and a newCD-ROM will be issued containing theproceedings of that conference.NNIHe discussed a small paging unit thatproduces an improvement in environmentalnoise levels of about 5 dB but is notcapable of alerting as many persons asdo current systems. He said that thereare problems in hospitals with acousticalmaterials mainly because of the need forbacterial control, and said that we mustimprove our acoustical materials. Heconcluded that hospitals are noisy and aregetting more so. There is little work on thequieting of hospitals and little data on theperformance of the staff.(Editors note: The written paper appearsin the Proceedings of NOISE-CON 05. Itis interesting to note that none of the 17references to technical papers refer to2005 December www.inceusa.org • www.noisenewsinternational.net • www.i-ince.org133
Page 1: NOISE/NEWSVolume 13, Number 42005 D
Page 5: President’s ColumnActivities With
Page 8 and 9: 114 www.inceusa.org • www.noisene
Page 10 and 11: Engineering a Quieter WorldThe 2006
Page 12 and 13: ExpositionA large Expo with display
Page 14 and 15: General Conference InformationCongr
Page 16 and 17: INTER-NOISE 2005 ReportSamir Gerges
Page 18 and 19: classical form of Brazilian popular
Page 20 and 21: auralization to take these psycho-a
Page 22 and 23: The team which will organize INTER-
Page 24 and 25: NOISE-CON 05 ReportNOISE-CON 05, th
Page 28 and 29: PrecisionAcoustical MeasurementsMea
Page 30: European News .....................
Page 33 and 34: JAPANTwo Japanese Societies celebra
Page 35 and 36: Spain: ALAVA Ingenieros S. A.+34 91
Page 37 and 38: Product NewsScantekScantek Appointe
Page 39 and 40: armature design provides electrical
Page 41 and 42: AcknowledgementsINCE/USA Liaison Pr
Page 43 and 44: Directory of Noise Control Services

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