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    <title>Transport Research International Documentation (TRID)</title>
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    <atom:link href="https://trid.trb.org/Record/RSS?s=PHNlYXJjaD48cGFyYW1zPjxwYXJhbSBuYW1lPSJzdWJqZWN0bG9naWMiIHZhbHVlPSJvciIgLz48cGFyYW0gbmFtZT0idGVybXNsb2dpYyIgdmFsdWU9Im9yIiAvPjxwYXJhbSBuYW1lPSJsb2NhdGlvbiIgdmFsdWU9IjAiIC8+PC9wYXJhbXM+PGZpbHRlcnM+PGZpbHRlciBmaWVsZD0ia2V5d29yZHMiIHZhbHVlPSImcXVvdDtFbmdpbmUmcXVvdDsgYW5kICZxdW90O3NvdW5kJnF1b3Q7IGFuZCAmcXVvdDtsZXZlbCZxdW90OyBhbmQgJnF1b3Q7bWVhc3VyZW1lbnQmcXVvdDsgYW5kICZxdW90O3Byb2NlZHVyZSZxdW90OyIgb3JpZ2luYWxfdmFsdWU9IkVuZ2luZSBzb3VuZCBsZXZlbCBtZWFzdXJlbWVudCBwcm9jZWR1cmUiIC8+PC9maWx0ZXJzPjxyYW5nZXMgLz48c29ydHM+PHNvcnQgZmllbGQ9InB1Ymxpc2hlZCIgb3JkZXI9ImRlc2MiIC8+PC9zb3J0cz48cGVyc2lzdHM+PHBlcnNpc3QgbmFtZT0icmFuZ2V0eXBlIiB2YWx1ZT0icHVibGlzaGVkZGF0ZSIgLz48L3BlcnNpc3RzPjwvc2VhcmNoPg==" rel="self" type="application/rss+xml" />
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    <copyright>Copyright © 2026. National Academy of Sciences. All rights reserved.</copyright>
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    <managingEditor>tris-trb@nas.edu (Bill McLeod)</managingEditor>
    <webMaster>tris-trb@nas.edu (Bill McLeod)</webMaster>
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      <title>Transport Research International Documentation (TRID)</title>
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      <title>Engine Sound Source Characterization Based on Inverse Numerical Acoustics</title>
      <link>https://trid.trb.org/View/1877131</link>
      <description><![CDATA[Inverse Numerical Acoustics (INA) is the process by which the measurements of the sound pressure near a vibrating object, such as an engine, can be used to reconstruct the surface velocities of the object. This is required when it is difficult to conduct measurement on the structure or when the full structural FE model is not available. In such scenarios, the INA technique allows to back calculate the operational vibrations based on operational near field pressure measurements. When the surface velocities of a vibrating object are known which are independent of the boundary conditions, then the object can be used as a source in any application to compute the sound pressure levels in the surrounding (far field). This paper describes an experimental procedure that relies on INA to characterize an engine noise source in this manner. To this end, a robotic manipulator first measured sound pressures at multiple points in the near acoustic field. This process resulted in an accurate mapping of the measured data onto the analysis model. INA analysis was then performed to reconstruct the surface velocities. Next, a validation of far field sound pressure levels at 1m away from the engine was carried out by performing forward acoustic analysis with the computed surface velocities as the source input. As a result, the reconstructed sound pressure levels show a good level of correlation with the test. This methodology can be used for integrating the engine as a noise source in various applications.]]></description>
      <pubDate>Thu, 09 Dec 2021 10:38:49 GMT</pubDate>
      <guid>https://trid.trb.org/View/1877131</guid>
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    <item>
      <title>Methodology for Sloshing Noise Measurement and Acoustic Target Definition for SCR Tanks to Improve Comfort</title>
      <link>https://trid.trb.org/View/1835647</link>
      <description><![CDATA[Within recent years, passenger comfort has become a main focus of the automotive industry. The topic is directly connected with acoustics, since sounds and noises have a major impact on the well-being of vehicle occupants. So-called “noise control” focuses on directly optimizing acoustic comfort by implementing innovative materials or geometries for automotive components and systems. One possibility to optimize the acoustics within a vehicle is connected to the phenomenon of sloshing in Selective Catalytic Reduction (SCR) tanks. Sloshing is a noise which is generated during normal driving situations by the motion of the Diesel Exhaust Fluid (DEF) in the tank. Until now, no procedure for measuring sloshing noise in SCR tanks has been defined, and neither a specific acoustic target which the SCR tanks need to fulfil. For this reason, it’s been developed a reproducible laboratory-based methodology to measure the sound generated by the tank and compare it with a defined sound pressure level target.         As a first step the different phenomena of sloshing noise generation have been deeply analyzed (hit, splash, clonk, bubble-jet), each of which can be attributed to a specific movement of the liquid inside the tank.         Aiming at a repeatable procedure which reflects the sound level occurring during realistic driving manoeuvres, the company designed and constructed a test bench able to reproduce real driving conditions of this kind and evaluated the results according to the identified target.         Subsequently, an examination was conducted to assess the transmission paths of the noise from the tank to the vehicle cabin as well as the effects of the engine and driving manoeuvres on how the sounds are perceived by passengers. For this purpose, sloshing noises recorded for different tanks were modified in order to prepare psychoacoustic listening sessions and identify the most important parameters influencing the annoyance.]]></description>
      <pubDate>Thu, 09 Dec 2021 10:38:41 GMT</pubDate>
      <guid>https://trid.trb.org/View/1835647</guid>
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    <item>
      <title>Procedure to Assess the Vibroacoustic Quality of a Diesel Engine in Assembly Workshop</title>
      <link>https://trid.trb.org/View/1818385</link>
      <description><![CDATA[Customers demand a higher quality level of the automobile vehicles. These demands include noise, vibration and harshness (NVH) quality as an important item.         The combustion engines are the main source of NVH on the vehicle, particularly in case of diesel engines. Manufacturers have focused their design efforts on reducing the noise and vibration levels transmitted to passengers and car drivers in order to improve the quality and comfort from a customer point of view. However the designer's effort to reduce these emissions of noise and vibration could be lessened because of the engine assembly process variation.         In the present work, a procedure to assess these variations in order to maintain NVH performances within the limits of design and to achieve the quality level expected by the customer is proposed.         To achieve it, the engine vibration level has been measured through three sensors allocated at strategic points. Some objective criteria based on the vibration level at certain frequencies have been established to assessing the engine quality level as a final step of the engine assembly process.]]></description>
      <pubDate>Thu, 09 Dec 2021 10:33:36 GMT</pubDate>
      <guid>https://trid.trb.org/View/1818385</guid>
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    <item>
      <title>Test Measurement Technique for Vehicle Cool Down Thermal Noises (Tick, Ping, Tink, Crinkle, Crackle)</title>
      <link>https://trid.trb.org/View/1817693</link>
      <description><![CDATA[Vehicle cool down noises are receiving more attention as the NVH quality standards rise. The typical observer describes these noises as ping/ting, tick/tink and crinkle/crackle. A new test procedure is presented that measures audible metallic type noises during vehicle cool down (after the engine has been shut off). Vehicle run conditions are recommended for noise replication in the field and for measurement standardization. An objective measurement system is described using sound pressure level. In the past, a measurement has been very difficult to quantify. A recommended report format concisely communicates this critical vehicle quality characteristic. It is a valuable tool for vehicle NVH comparison, ranking and benchmarking.]]></description>
      <pubDate>Thu, 09 Dec 2021 10:33:30 GMT</pubDate>
      <guid>https://trid.trb.org/View/1817693</guid>
    </item>
    <item>
      <title>Battery electric vehicles. What is the future of the NVH package?</title>
      <link>https://trid.trb.org/View/1605623</link>
      <description><![CDATA[In this article, the current NVH (Noise Vibration Harshness) performance in the interior passenger compartment of Battery Electric Vehicles (BEVs) is compared with their Internal Combustion Engine (ICE) counterparts.  Electric powertrains can potentially bring some remarkable changes for vehicle Noise, Vibration and Harshness (NVH) due to noise from battery cooling and powertrain whine among others, in addition to tire and aerodynamic noise becoming more prominent in the absence of a standard Internal Combustion Engine (ICE). To investigate the NVH performance, experimental tests are carried out in two different configurations: besides interior Sound Pressure Level (SPL) measurements in operational conditions on the road under Wide Open Throttle (WOT) acceleration and constant speeds of 50, 80 and 120 km/h, reciprocal transfer function measurements in a semi-anechoic room have also been carried out. In light of the test results and the main global automotive market trends for electric vehicles, it looks reasonable to foresee that the NVH package of BEVs is certainly not going to become redundant anytime soon. Electric vehicles have to face many of the NVH issues that conventional ICE vehicles have faced until today. Tire and aerodynamic noise is equally present for any kind of powertrain, while ancillaries (e.g. air conditioning compressor, brake booster vacuum pump) and running components (e.g. battery and electrical motor cooling systems) devoted to electric powertrains will make additional noise. In addition, the electric motor, although generally quieter than ICE, can still emit remarkable high frequency noise. In general, vehicles need to become quieter, lighter and more energy-efficient, no matter the type of propulsion. As a consequence, new types of drives such as electric cars do require lightweight NVH components that integrate acoustic and aerodynamic functions. Electric vehicles also open innovative application areas for the treatment and insulation of bothersome high frequency noise from the electric motor, as well as road and wind noise. This is particularly true considering that there is also a growing demand from motorists for a significantly increased driving comfort for future vehicles. (A)]]></description>
      <pubDate>Thu, 25 Jul 2019 10:04:37 GMT</pubDate>
      <guid>https://trid.trb.org/View/1605623</guid>
    </item>
    <item>
      <title>Laermmindernde Strassenoberflaechen innerorts - eine Bestandsaufnahme / Low noise urban road surfaces - state-of-the-art</title>
      <link>https://trid.trb.org/View/936290</link>
      <description><![CDATA[Im Rahmen des Konjunktur-Pakets II beteiligt sich der Bund mit Finanzhilfen an der Laermsanierung kommunaler Strassen. Grundlage fuer die Foerderung ist das "Gesetz zur Umsetzung von Zukunftsinvestitionen der Kommunen und Laender". Nach diesem Gesetz werden Investitionen im Bereich der kommunalen Strassen ausdruecklich auf Massnahmen des Laermschutzes beschraenkt. In jedem Einzelfall muss die Laermsituation verbessert werden und diese Verbesserung moeglichst konkret dargelegt werden. Problematisch ist aber, dass es derzeit keine Strassenoberflaechen gibt, denen eine laermmindernde Wirkung bei innerorts ueblichen Geschwindigkeiten zugewiesen ist. Geeignete Messverfahren zur Bestimmung der Minderungspegel stehen bereits zur Verfuegung. An Verfahren zur Bewertung und Klassifizierung von Strassenoberflaechen wird derzeit noch gearbeitet. Gleichwohl sind bereits vielversprechende Strassenoberflaechen bekannt, die vermutlich als laermarm (Minderung mindestens 2 dB(A)) klassifiziert werden koennen, wenn ein umfangreiches Messprogramm die Klassifizierung dieser Belaege rechtfertigt. Die RLS-90 werden derzeit ueberarbeitet. Insbesondere die Emissionsannahmen sind nach fast 20 Jahren veraltet und beduerfen einer Aktualisierung. Um zukuenftigen Entwicklungen bei der Geraeuschemission Rechnung tragen zu koennen, soll in den neuen RLS statt auf eine Tabelle mit Korrekturwerten D(StrO) auf ein Verfahren verwiesen werden, mit dem neue Werte ermittelt werden koennen. Dabei sollte auch eine Aufteilung nach Motor- und Antriebsgeraeusch beziehungsweise Reifen-Fahrbahn-Geraeusch sowohl von Pkw als auch von Lkw vorgenommen werden. ABSTRACT IN ENGLISH: Within the scope of the economic situation package II the alliance with financial assistance takes part in the noise renovation of municipal streets. Basis for the support is the "law of the conversion of future investments of the local authority districts and countries". According to this law investments in the area of the municipal streets are limited expressly to measures of the noise prevention. In every single case the noise situation must be improved and this improvement is to be demonstrated. However, it is problematic that there are currently no street surfaces to which a noise reduction effect is assigned for usual urban speeds. Suitable measuring procedures for determining these noise reduction effects are already available. The work on procedures for the assessment and classification of the noise from street surfaces is still ongoing. Anyhow promising street surfaces are already known which can  presumably be classified as noise reduced (decrease of at least 2 dB(A)) if an extentive measuring programme justifies the classification of these layers. RLS-90 are reworked currently. In particular the issue emission has become outdated after nearly 20 years and needs an updating. To be able to take into account future developments in the area of noise, the table with correction values DStrO should be replaced by a procedure with which new values can be determined. Besides, a subdivision should be also carried out for engine noise and tyre noise by passenger cars as well as by truck]]></description>
      <pubDate>Wed, 06 Oct 2010 15:08:03 GMT</pubDate>
      <guid>https://trid.trb.org/View/936290</guid>
    </item>
    <item>
      <title>Strassenoberflaechen fuer Laermminderung innerorts / Road surfaces for noise reduction in urban areas</title>
      <link>https://trid.trb.org/View/927438</link>
      <description><![CDATA[Im Rahmen des Konjunktur-Pakets II beteiligt sich der Bund mit Finanzhilfen an der Laermsanierung kommunaler Strassen. Grundlage fuer die Foerderung ist das "Gesetz zur Umsetzung von Zukunftsinvestitionen der Kommunen und Laender". Nach diesem Gesetz werden Investitionen im Bereich der kommunalen Strassen ausdruecklich auf Massnahmen des Laermschutzes beschraenkt. In jedem Einzelfall muss die Laermsituation verbessert werden und diese Verbesserung moeglichst konkret dargelegt werden. Problematisch ist aber, dass es derzeit keine Strassenoberflaechen gibt, denen eine laermmindernde Wirkung bei innerorts ueblichen Geschwindigkeiten zugewiesen ist. Geeignete Messverfahren zur Bestimmung der Minderungspegel stehen bereits zur Verfuegung. An Verfahren zur Bewertung und Klassifizierung von Strassenoberflaechen wird derzeit noch gearbeitet. Gleichwohl sind bereits vielversprechende Strassenoberflaechen bekannt, die vermutlich als laermarm (Minderung mindestens 2 dB(A)) klassifiziert werden koennen, wenn ein umfangreiches Messprogramm die Klassifizierung dieser Belaege rechtfertigt. Die Richtlinien fuer Laermschutz an Strassen (RLS-90) werden derzeit ueberarbeitet. Insbesondere die Emissionsannahmen sind nach fast 20 Jahren veraltet und beduerfen einer Aktualisierung. Um zukuenftigen Entwicklungen bei der Geraeuschemission Rechnung tragen zu koennen, soll in den neuen RLS statt auf eine Tabelle mit Korrekturwerten D(Index StrO) (Korrektur fuer unterschiedliche Strassenoberflaechen) auf ein Verfahren verwiesen werden, mit dem neue Werte ermittelt werden koennen. Dabei sollte auch eine Aufteilung nach Motor- und Antriebsgeraeusch beziehungsweise Reifen-Fahrbahn-Geraeusch sowohl von Pkw als auch von Lkw vorgenommen werden. (A) ABSTRACT IN ENGLISH: Within the scope of the economic situation package II the alliance with financial assistance takes part in the noise renovation of municipal streets. Basis for the support is the "Iaw of the conversion of future investments of the Iocal authority districts and countries". According to this Iaw investments are limited in the area of the municipal streets expressly to measures of noise prevention. In every single case the noise situation must be improved and this improvement is to be demonstrated. However, it is problematic that there are currently no pavement surfaces to which a noise reduction effect is assigned for usual urban speeds. Suitable measuring procedures for determining these noise reduction effects are already available. The work on procedures for the assessment of the noise from pavement surfaces is still ongoing. Anyhow promising pavement surfaces are already known which can be presumably classed as noise reduced (decrease of at least 2 dB(A)) if an extensive measuring programme justifies the classification of these layers. RLS-90 are reworked currently. In particular the noise assumptions have become outdated after nearly 20 years and need an actualisation. To be able to take into account future developments with the noise issue, the table with correction values DStrO should be replaced by a procedure with which new values can be determined. Besides, a subdivision should be also carried out for engine noise and tyre noise by passenger cars as well as by trucks. (A)]]></description>
      <pubDate>Sat, 28 Aug 2010 11:22:39 GMT</pubDate>
      <guid>https://trid.trb.org/View/927438</guid>
    </item>
    <item>
      <title>ART OF NOISE</title>
      <link>https://trid.trb.org/View/683329</link>
      <description><![CDATA[This paper describes a portable means of measuring pass-by noise from traffic. New regulations demand lower noise levels. Any measurement system needs to be compact, easy to set up and resistant to poor weather conditions. Noise is emitted by the engine, air intake, fumes exhaust and tyres, and caused by aerodynamic effect around the vehicle. Standard test requirements are detailed in the paper. This system is composed of a photocell and reflector, to trigger measurement, radar to track position and speed of the vehicle and on-board sensors for engine revolutions and throttle position. Data is processed by a portable analyzer and transferred to a notebook computer, where it is tabulated and plotted in graphic form for evaluation. Further developments are envisaged to enable testing of interior vehicle noise.]]></description>
      <pubDate>Thu, 03 May 2001 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/683329</guid>
    </item>
    <item>
      <title>ON PROBLEMS WITH TYRE/ROAD NOISE ON TRUCKS OF HIGH ENGINE RATING</title>
      <link>https://trid.trb.org/View/425056</link>
      <description><![CDATA[During both driving under acceleration and driving at speeds constantly above 60 km/h the tyre/road noise can become the dominant factor in the overall vehicle noise. The main influencing quantities are to equal degrees the tyres and the road, but the vehicle being measured too has a large influence. The characteristic values determined on test beds do not reflect the noise of a tyre on the road and are therefore unsuitable for assessment purposes. A measurement procedure planned to determine the tyre/road noise must be designed in such a way that with further stages in the development of tyres and of road surfaces a noise reduction in real transport conditions is achieved.  (A)  For the covering abstract see IRRD 869246.]]></description>
      <pubDate>Thu, 25 May 1995 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/425056</guid>
    </item>
    <item>
      <title>THE STATIONARY NOISE TEST - PROBLEMS AND PROGNOSIS</title>
      <link>https://trid.trb.org/View/276923</link>
      <description><![CDATA[The stationary test procedure used in Australia for the measurement of vehicle exhaust noise is based on, but not identical to, that used in Europe.  It was introduced after extensive study of the results expected from the in-service vehicle fleet and the errors associated with the test.  For cars the microphone is positioned 0.5 metres from the exhaust pipe and the engine speed is held constant at three quarters of the engine speed at maximum power (esmp).  In New South Wales new cars are tested by the stationary procedure to ensure that citizens are not purchasing vehicles exceeding the 90 db(a) limit (and therefore in breach of the law) when new.  This testing programme permits the collection of repeatable results, and has therefore led to the detection of some phenomena not previously reported with the stationary procedure.  This paper discusses some of those phenomena.  (TRRL)]]></description>
      <pubDate>Fri, 31 Oct 1986 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/276923</guid>
    </item>
    <item>
      <title>OPERATIONAL PROCEDURE. MEASUREMENT OF TYRE-ROAD CONTACT NOISE. CRR MEASUREMENT TECHNIQUE MF 50/84</title>
      <link>https://trid.trb.org/View/216640</link>
      <description><![CDATA[An operational procedure is described for measuring the noise level due to contact between the road and the tyres of a vehicle which is decelerating freely with its engine switched off.  The first part of the paper deals with measurement of the maximum noise level radiated outside the vehicle when passing a fixed microphone, and the second with the average noise level prevailing in the passenger and driving compartment.  First published by Centre de Recherches Routieres, Bruxelles, 1984.  (TRRL)]]></description>
      <pubDate>Wed, 31 Jul 1985 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/216640</guid>
    </item>
    <item>
      <title>SOME ASPECTS OF MOTORCYCLE NOISE EMISSION</title>
      <link>https://trid.trb.org/View/203683</link>
      <description><![CDATA[This report compares the noise emission characteristics of motorcycles with noise emission for other vehicle types and attempts to evaluate the relevance of standard methods of measuring motorcycle noise emission for regulation test purposes.  It was found that the noise emitted by motorcycles when operated at steady speed in top gear is governed by a single function of vehicle speed, the noise increasing by about 10 db(a) for each doubling of road speed.  This characteristic follows closely the generalised level speed function obtained for passenger cars operating freely in traffic.  On dry road surfaces motorcycle rolling noise levels are generally substantially lower than the noise levels generated by the power unit.  While there seems to be little opportunity to develop a noise test procedure which is commensurate with the wide range of in-use operating conditions for motorcycles, the results show that the full throttle acceleration test as described in EEC Directive 1015/78, although not perfect does meet the basic requirements of a regulation test procedure. However, further work on the full effects of the 1015 test procedure on a wider range of motorcycle types is desirable.  The BS3425 test was not found to be suitable for use on high powered, large engine capacity, motorcycles.  The EEC 1015 close proximity stationary test was found to fulfill the basic requirements of an in-use test procedure.  The levels achieved under the test were found to be related to engine capacity, indicating that in-use limits should be set making some allowance for the larger engine capacity motorcycles. (Author/TRRL)]]></description>
      <pubDate>Tue, 30 Jul 1985 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/203683</guid>
    </item>
    <item>
      <title>A COMPARISON OF METHODS FOR MEASURING THE NOISE OF INDIVIDUAL MOTOR VEHICLES</title>
      <link>https://trid.trb.org/View/205791</link>
      <description><![CDATA[The aim was to determine the correlation between motor vehicle noise tests used in Australia and overseas and to examine alternatives to the current Australian Environment Council (AEC) endorsed stationary motor vehicle noise tests and to recommedn alternatives which correlate more closely to the new vehicle driveby test.  The analysis was based on the a-weighted results of tests on nineteen trucks, six buses and nineteen motorcycles.  The vehicles were subjected to a battery of tests: acceleration; constant speed; coastby; and stationary.  For diesel vehicles there is a very highly significant correlation between the result of the Australian Design Rule (ADR) 28a test and the stationary "blip" test with the noise level measured 1.0 M from the exhaust outlet.  The driveby levels recorded for many of the heavy vehicles seemed to be influenced strongly by exhaust noise.  Reductions in the driveby levels seemed to be available for most vehicles without the need to change tyres or transmission components.  A very highly significant correlation was found between the results of the ADR 28 test and that of the 50 per cent ESMP stationary test recorded at 0.5 M.  Exhaust noise appeared to dominate the driveby levels recorded for the larger motorcycles.  The sale and fitting of replacement exhaust system should be carefully monitored.  The current in-service limit of 100 db (a) seems to be too high.  The majority of motorcycles were comfortably below the limit, and an analysis based on the existing adr 28 levels indicated that 100 db(a) is too high. (TRRL)]]></description>
      <pubDate>Fri, 30 Nov 1984 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/205791</guid>
    </item>
    <item>
      <title>ASSESSMENT OF LOCOMOTIVE CREW IN-CAB OCCUPATIONAL NOISE EXPOSURE</title>
      <link>https://trid.trb.org/View/161940</link>
      <description><![CDATA[The railroad industry, unlike most other U.S. industries, is not subject to the safety regulations of the Occupational Safety and Health Administration.  Instead, railroad workers are covered by the safety regulations of the Federal Railroad Administration (FRA). This report documents an extensive study designed to assess the noise environment in locomotive cabs.  Operational duty cycle and in-cab sound level data are presented for 18 test runs made on 16 different locomotives used in wide range of operational modes (e.g., through freight and local transfer freights), varied terrains (mountainous, undulating and flat) and varied trip lengths (6 to 12 hours).  The general conclusion of this study is that there does not appear to be a widespread problem of overexposure to noise based on the same type of evaluation as currently used by OSHA (only 1 out of 18 test runs exceeded the criteria).  The noise exposure is within acceptable limits because the operational duty cycle is such that the sources which generate high sound levels (horn and brake) are operating only for short periods of time and because the locomotive spends a great deal of time idle (diesel engine sound levels below 90 dB). However, there was one test run for which an overexposure to noise was measured.  To pinpoint such cases where overexposure to noise may occur, a simplified testing procedure is developed.  This test consists of making in-cab sound level measurements of engine notch 8 (no load), horn sounding and brake application with the locomotive stationary.  With these three sound level measurements and an estimate of the time that the locomotive is operating on-line, the in-service noise dose can be estimated and a pass/fail assessment made of whether the noise exposure might exceed acceptable limits.]]></description>
      <pubDate>Wed, 18 Feb 1981 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/161940</guid>
    </item>
    <item>
      <title>THE MEASUREMENT OF LOCOMOTIVE NOISE AT EXISTING RAILROAD TEST SITES</title>
      <link>https://trid.trb.org/View/150481</link>
      <description><![CDATA[A study was undertaken to examine the feasibility of accurately measuring the noise from locomotives at existing load cell sites in the absence of sites conforming with U.S. Environmental Protection Agency standards. It was found through measurements at seven typical sites and one conforming load cell test site involving ten locomotives that reasonably accurate measurements were possible for the locomotive operating fully loaded at throttle 8. Errors, when they occurred, were due primarily to sound reflecting off nearby buildings. Measurements with the locomotive in idle were generally difficult because of high background noise at these sites.  A passby test procedure was also examined and found to provide reasonably accurate measurement of locomotive noise at throttle 8, full load.]]></description>
      <pubDate>Wed, 07 May 1980 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/150481</guid>
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