• Construction Noise
• Measurement
• Noise Barriers
• Noise Compatible Planning
• Regulation and Guidance
• Resources
• Tire Pavement Noise
• Traffic Noise Model
• Training

Recommended Best Practices for the Use of the FHWA Traffic Noise Model (TNM)

III. Best Practices for Quality Assurance of TNM Input and Results

Introduction

Quality assurance / quality control (QA/QC) of a product or service, such as an environmental noise assessment or a noise abatement design report, depends upon the processes and procedures that the responsible organization (state highway agency [SHA], engineering firm, acoustical consulting firm, etc.) has set in place. That is, quality assurance depends upon the organization's Quality Management System (QMS). This report provides guidance to those organizations looking to incorporate QA practices into highway noise studies or to enhance policies already in place, and provides examples of simple processes and/or tools that may be used for QA. The recommended processes and tools include the use of spreadsheets and special views within the FHWA TNM to verify the accuracy of vertical geometry, as well as the use of checklists to document not only the development and review of TNM object input, but also the development and review of noise study reports and noise abatement design reports.

This chapter presumes the highway noise analyst has a thorough understanding of FHWA guidance for the application of 23 CFR 772 in the analysis and abatement of highway noise.^[25] Highway noise analysts also should become familiar with the recommended Best Practices for the application of the FHWA TNM to “non-routine” scenarios.^[26]

The following sections provide an overview of QA concepts and some of the components of a QMS that are applicable to highway noise studies, a sample QA plan, recommended QA processes for the development and review of TNM object input, recommended QA processes for the review of TNM-computed sound levels and noise barrier results, sample checklists for the development and review of TNM noise analysis reports, and additional resources for noise study report guidance and checklists. The appendices contain a copy of the Florida DOT's QC checklist for the review of TNM input files and a copy of the Virginia DOT's “Noise Report Guidance and Accountability Checklist” and a project close-out form.

Overview of Quality Assurance (QA) Concepts

The International Organization of Standardization (ISO) develops voluntary technical standards for the purpose of adding value to a variety of business operations by supporting “the development, manufacturing and supply of more efficient, safer and cleaner products and services.” The ISO 9000 family of standards provides the basic requirements for a QMS that an organization must fulfill to provide products and services that meet customers' expectations and applicable regulatory requirements.^[27] The recommended QA processes described in the following sections are largely based on and strive to be consistent with the concepts presented in the ISO 9000 family of standards. The general requirements for a QMS are identified in ISO 9001 and are quite extensive.^[28] For the purposes of developing QA processes for TNM models and noise analysis reports, the study team selected those requirements from ISO 9001 that are the most relevant to the objectives of this study. Therefore, while the recommended QA processes are based on the ISO standards, adoption of and adherence to these QA processes does not fulfill all of the requirements for certification and/or registration of an organization's QMS by ISO.

The components of a QMS that form the basis of the recommended QA procedures in this document are as follows:

• Documented statements of a quality policy and quality objectives embodied in a QA Plan,
• The processes needed for QA of TNM models and noise study reports, and their application,
• The sequence and interaction of the processes, and
• Documents and records, in the form of checklists, necessary to ensure effective planning, operation, and control of the QA processes.

As always, the highway noise analyst is encouraged to check with the SHA staff in their state or district before embarking on a noise study or adopting any of the QA processes identified herein. Research undertaken for this study revealed that several SHAs already have QA/QC-related procedures and policies in place. Several SHAs are using checklists for the content and format of noise analysis reports.

Sample Quality Assurance Plan

The implementation of quality assurance into an organization's processes requires the preparation of a QA Plan. In its most basic form, the QA Plan documents the established procedures and processes for implementing the QA Plan and identifies the objectives of the QMS. The QA Plan also may identify management's responsibilities in the QA process and minimum requirements for staff working on a highway noise study. Of course, there is no “one size fits all” approach to adopting a QA Plan. The size and scope of the QA Plan depends on a number of factors, including the size of the organization implementing the Plan and the complexities of the QA processes.

It is the responsibility of the Principal Investigator (PI) and/or Project Manager (PM) to communicate the goals and objectives of the QA Plan to all team members working on a highway noise study. The QA Plan should be reviewed and updated on a periodic basis to ensure that its goals and objectives are consistent with applicable state and Federal policies and regulations. For example, organizations may elect to review and update the QA Plan and any supporting documents (e.g., checklists) on a schedule that coincides with the SHA's revisions and updates to the State Noise Abatement Policy.

Appendix E contains a sample QA Plan that presents some concepts that organizations may wish to consider when drafting a QA Plan. Note that this sample QA Plan is provided solely as an example and that the language appearing in it is not mandated by the FHWA. For instance, although some state SHAs may wish to do so, the FHWA is not mandating the amount of experience for different levels of staff who may work on a highway noise study. The sample QA Plan is based on one organization's approach to QA.

QA Processes for TNM Input

The recommended QA/QC processes in this section apply to the data used as input (coordinates, roadway details, topographic data, land use, traffic, etc.) to generate TNM objects.

Project Plans, Profiles, and Cross-sections

The SHA's Highway Design Manual (HDM) provides current requirements and guidance on highway design methods to ensure uniformity of design practice throughout the highway system under its jurisdiction. It is the primary source of guidance for the design of highway facilities from scoping to preliminary design. The HDM not only contains design criteria for different classifications of highway facilities, as well as for interchanges and signalized intersections, but also typically contains standards and procedures for computer aided design (CAD). The CAD standards and procedures assure uniformity of practice and the creation of electronic data for projects designed by or for the SHA. The HDM provides guidance and standards for the use of engineering software used for highway design, and specific configuration settings for the engineering software.^[29] While a thorough understanding of the HDM is not a prerequisite for highway noise analysis, the HDM can be a resource for the highway noise analyst. The highway noise analyst should coordinate with the highway designers.

At a minimum, the project plans and cross-sections provided to the highway noise analyst should contain the following design features for both the existing highway and the proposed highway. In general, if the project plans, profiles, and cross-sections were developed according to the SHA's HDM, these design features should be available to the highway noise analyst. The following design features are applicable to project and non-project roadways alike, to the extent that data are available for the latter:

• Project limits,
• Locations of general purpose lanes, special use lanes (e.g., high occupancy vehicle lanes, special tolling lanes, etc.), acceleration and deceleration zones for ramps, shoulders,
• Locations where the highway would be on structure and on fill,
• Limits of construction, including toe of slope and top of cut,
• Edge of pavement,
• Rights-of-way,
• Civil station numbering baseline,
• Rest areas and truck weigh stations,
• Existing noise barriers,
• Locations of jersey barriers, and
• Lane striping.

As necessary, the project plans should contain information about other project features, including:

• Bodies of water (rivers, ponds, lakes, etc.) including wetland resources and buffer zones,
• Storm water management basins,
• Other transportation facilities (railroads, bike paths, shared use paths, etc.)
• Utilities (natural gas, telecommunications, water, electricity, etc.),
• Existing development along the highway corridor, and
• If available, future proposed development within the project corridor.

The most commonly used coordinate system for highway projects is the State Plane Coordinate System (SPCS) based on the North American Datum of 1983 (NAD 83). Elevation data are commonly referenced to the North American Vertical Datum of 1988 (NAVD 88).^[30] Of course, the highway noise analyst should check with the project's designers or the SHA noise specialist to verify the preferred coordinate system for the project. When reviewing the project plans/profiles/cross-sections, the highway analyst should:

• Identify/verify the coordinate system,
• Identify/verify the vertical datum, and
• Obtain the metadata^[31] for the project plans/profiles/cross-sections.

Topographic Data and Land Use

Typically, the plans, profiles, and cross-sections prepared for a highway project provide information that is limited to within the right-of-way. Although some SHAs and/or highway designers may develop plans that provide useful information about the project's environs beyond the limits of the right-of-way (e.g., topographical features, land use, locations of non-project roads and other transportation facilities, etc.), this is not always the case. In such cases, the highway noise analyst must supplement the project plans, profiles, and cross-sections with information from third parties. Such third-party information includes topography, land use, locations of bodies of water, forested lands, and orthographic aerial imagery.

Geospatial data are currently available through a variety of clearinghouses, catalogs, and portals, which are hosted by a broad range of partners/stakeholders, including various federal, state, local, and tribal governments through their agencies, as well as academia and the private sector. Refer to Chapter I for sources of publicly available elevation data and examples of other sources of geospatial data from various governmental agencies.

In addition to the sources referenced above, high-quality orthographic aerial imagery is available from applications such as Google Earth, Google Maps, and Bing Maps Land. These readily available applications provide aerial photographs, as well as “Street” or “Bird's eye” views, with ever-increasing coverage of the conterminous United States.^[32] Visual inspection of the aerial photographs and other imagery obtained from these sources provides a means to determine land use along a highway corridor with a reasonable amount of accuracy. However, the ease with which land use can be derived from such sources depends on the quality of the imagery, which often varies from state to state and even within a state. Even if high quality aerial photographs and/or other geospatial data are available, a “windshield” survey, performed by personnel in the field, should be included as part of every highway noise study to verify land use along a project corridor. During a windshield survey, field personnel should identify the following land use details:

• FHWA Activity Category for all properties along the highway corridor, within 500 to 1,000 feet of the project limits,
• For multi-family residences, the number of dwelling units associated with each building and the locations of “exterior areas of frequent human use” such as patios, balconies and common areas,
• For FHWA Activity Category C land use, the locations of “exterior areas of frequent human use” (e.g., the locations of picnic tables, playground equipment, athletic fields, etc.),
• For FHWA Activity Category D land use, the construction of the building structure (e.g., wood frame, masonry, etc.) containing noise-sensitive activities,
• For FHWA Activity Category E land use, the locations of “exterior areas of frequent human use” (e.g., the locations of outdoor tables at restaurants, pools at motels, sitting areas, playground equipment, athletic courts), and
• While not necessarily a part of a windshield survey, the highway noise analyst should contact the local planning department to obtain site plans for proposed future planned development for undeveloped lands that are permitted for FHWA Activity Categories B, C, or E.

Loudest-hour Traffic

In accordance with 23 CFR 772.9(d), “in predicting noise levels and assessing noise impacts, traffic characteristics that would yield the worst traffic noise impact for the design year shall be used.” Research conducted in conjunction with this study revealed that SHAs have different views as to what constitutes the traffic characteristics that yield the “worst noise hour” or the “loudest hour of the day.” For example:

• The majority of SHAs use Design Hourly Volumes (DHV) along with the corresponding speeds,
• One SHA uses either Level-of-Service (LOS) C traffic volumes, or DHV, with posted speeds limits,
• Another SHA calculates hourly vehicle volumes (over a 15- or 24-hour period) based on the equations contained in the latest version of the Highway Capacity Manual (HCM), combined with either posted speed limits or operational speeds, and then identifies the single hour that produces the highest traffic noise level along a particular stretch of the highway.

Some SHAs have published detailed procedures for the development of traffic data (vehicle volumes, speeds, and classifications) for use in highway noise studies. Two examples are Florida DOT and Virginia DOT. Their procedures are summarized below:

• In May 2015, the Florida DOT (FDOT) published a new guidance document to assist highway noise analysts “in the prediction of existing and future traffic noise levels and the evaluation of the effectiveness of noise barriers while providing consistent, predictable, and repeatable noise studies.”^[33] The FDOT Handbook provides references to more detailed guidance^[34],[35] on the development of traffic conditions that are representative of the “worst case” noise condition. For FDOT noise studies, the “worst case” traffic noise condition is based either on LOS C volumes and posted speed limits or Directional Demand Hourly Volumes (DDHV). The FDOT Handbook provides guidance on the calculation of DDHV in the event that traffic volumes are provided in the form of Annual Average Daily Traffic (AADT).
• The Virginia DOT (VDOT) considers hourly traffic volume, speed, and vehicle mix for both peak hours and off-peak hours, to the extent that such data are available, to determine the worst noise hour of the day. The Virginia DOT experience is that while the peak traffic hour often coincides with the worst noise hour, it is not always the case. For example, when peak-hour traffic volumes approach the capacity of a highway facility, operating speeds may be affected, causing the worst noise hour to differ from the peak traffic hour. In addition, off-peak truck percentages or atypical hourly traffic distributions may have the same effect. The Virginia DOT has found that the worst noise hour may coincide with off-peak hours due to peak-hour congestion, especially on predominantly commuter routes.^[36]

As demonstrated by the different approaches used in the previous examples, the highway noise analyst should verify the established procedures for developing worst case traffic conditions, if any, with the noise specialist at the SHA in which the highway project is located. When developing the worst noise hour traffic for a highway project, the following Best Practices also should be considered:

• Traffic data should be developed for major non-project roadways within the study area; non-project roadways may dominate the noise environment at a receiver of interest and consequently limit the effectiveness of a noise barrier.
• If hourly traffic data are available, conduct a “loudest hour” analysis to determine the hourly traffic conditions (vehicle volume, speed, and mix) that combine to produce the worst noise hour of the day. Experience has shown that the loudest hour does not always coincide with either of the peak traffic hours. In some cases, off-peak hours may be the worst case for noise.
• If the traffic for the worst-case noise hour is based on a capacity-related approach, ensure that the vehicle speeds are not representative of a congested roadway. The traffic conditions for the worst noise hour should represent free-flow traffic conditions and not conditions for a congested facility.
• If the worst noise hour is based on DHV and speeds, evaluate the effect of directional splits for the peak traffic hours on computed noise levels adjacent to the highway. Directional splits can have non-negligible effects on computed noise levels, especially for commuter roadways. If the effect of directional split is more than 1 decibel, consider modeling different peak traffic hours for noise-sensitive land use on opposite sides of the highway.
• Long-term noise monitoring, for a minimum of 24 consecutive hours, often is used to identify the worst noise hour for existing conditions. The long-term noise measurement data along with 24-hour traffic data can inform the loudest hour determination for the future Design Year scenarios.
• Consider the recommended Best Practices for the distribution of traffic across lanes of a multiple-lane highway that are described in detail in Chapter I.

These QA processes presume that the underlying data used to create the TNM objects are accurate and obtained from reliable sources. Upon the completion of a TNM model and prior to calculating sound levels, the highway noise analyst should verify that the input data were used to produce an accurate model of highway traffic noise. There are no shortcuts when conducting a review of TNM object input. The QA processes described below require careful attention to detail and a methodical approach on the part of the reviewer. The following table provides some items to consider when reviewing TNM objects.

QA Processes for TNM Objects

TNM Skew Sections, Profiles, and Perspective Views

The PI, PM, or highway noise analyst conducting a review of a completed TNM run should make use of the visualization tools that are available in the FHWA TNM to check the vertical geometry of TNM objects. TNM's skew sections, profiles, and perspective views provide a quick way to check gross errors in vertical geometry. The visualization tools within the FHWA TNM are somewhat limited in functionality, especially with respect to Version 2.5. Therefore, more often than not, a more detailed review of the vertical geometry may be required.

Spreadsheets and GIS- or CAD-based Methods

The PI, PM, or highway noise analyst conducting a review of a completed TNM run should make use of the spreadsheet-based tools and the functionality of CAD and/or GIS applications to check the project geometry, especially for larger, more complex projects. Such tools allow for a more thorough examination of roadway profiles and grades, and allow the highway analyst to calculate roadway grade explicitly.

CAD and GIS applications also allow the highway analyst to check the proximity of various TNM object points to one another. CAD- and GIS-based tools allow highway noise analysts to code very detailed complex and geometry with relative ease. However, experience has found that automated methods for object creation can result in extraneous points in the database caused by “double-clicks” during the digitizing process. Spreadsheet tools, as well as CAD- and GIS-based tools can help users identify extraneous points and eliminate them from a TNM run, thereby minimizing potential issues with the FHWA TNM database. Note that TNM's “Input Check” (version 2.5) has been found to miss instances of points that are too close to one another.

Sample Checklist for TNM Input

The Florida DOT has developed a checklist for the review of TNM objects and TNM input. A copy of the QA checklist is provided in Appendix F.

QA Processes for TNM Results

This section provides recommended QA processes for the review of TNM sound-level results and noise abatement designs. QA processes are described for three different scenarios: sound-level results from a single TNM run (without noise barriers for abatement); sound-level results where more than one TNM run is used to compute sound levels (i.e., for comparing sound-level results across multiple alternatives of a NEPA noise study); and sound-level results for noise barrier design.

This section presumes that the highway noise analyst has performed a noise model validation and has demonstrated that predicted traffic noise levels are within +/- 3 dBA of monitored traffic noise levels at each of the noise measurement sites.

Sound-Level Results from a Single TNM Run without Noise Barriers for Abatement

These QA processes apply to sound-level results from a single TNM run that does not contain noise barriers for abatement (but may contain noise barriers used to represent large buildings). The purpose of such a TNM run is to determine the extent of noise impact within a common noise environment and whether noise barriers are warranted.

• Review results graphically, preferably with GIS, with sound levels displayed adjacent to receiver locations on a base map showing buildings, terrain, existing roads, and any proposed roadways.
• Observe and make note of overall trends in sound levels with distance.
• Use color codes for the symbols that represent the receiver locations to convey information about noise impact and/or use labels to show sound levels at receiver locations to help determine the most important receivers.
• Look for outliers with unusually high or low sound levels, then investigate each one to see that the predicted sound level is justified (or not.). For such receivers with sound levels that do not follow the overall trends, look for the following elements in the TNM run that may be responsible for differences:
• Shielding by nearby buildings will tend to reduce sound levels, whether the buildings are coded as building rows or as fixed-height barriers.
• Elevation differences between the source roadways and the receiver often will affect sound levels. Higher elevation often means higher sound levels unless the roadway is in a cut and the top of cut provides noise shielding.
• Ground type will affect sound levels such that significant areas of pavement or water between the roadways and receivers will tend to increase predicted sound levels.

Sound-Level Results where more than one TNM Run is used to Compute Sound Levels at the Same Receivers

These QA processes apply to TNM models and results that are prepared for an environmental document, where sound levels are computed for the existing conditions, along with the Design-year No-build and Build alternatives. These procedures do not consider noise barriers for abatement.

• A graphical review of the sound levels from each TNM run at each receiver is helpful. They should be color coded or ordered to make identification of the alternative that produced the results easy (round sound levels to whole decibels for ease of quick review and determining differences).
• Another very useful approach for finding trends and outliers is to compute differences in the sound levels between the different alternatives in a spreadsheet. Outliers can be spotted easily by scanning the difference lists of sound levels.
• All trends and outliers in sound-level differences by receiver between alternatives should be investigated and should appear reasonable based on knowledge of differences between the alternatives being compared in the areas of:
• Traffic (particularly important when comparing existing and future no-build alternatives, as the roadway geometry is usually the same).
• Receiver distances to roadways - differences in build case alternatives should have logical differences in receiver sound levels.
• Roadway geometry and elevation - differences in elevation or the introduction of new ramps will change sound levels; such differences should be logical based on the geometric differences.

Sound-Level Results where Noise Barriers are being Evaluated for Abatement

The highway noise analyst should consider using the Noise Barrier Optimization Tool (NBOT) described in Chapter II. Its use helps to ensure consistency in the presentation of results and barrier calculations, and serves to document the noise barrier design process that yields the most cost-effective noise barrier design that meets the SHA's acoustical feasibility and design goals. The NBOT also provides a quick and effective way to review the TNM-computed sound-level results across multiple barrier analyses. Use of the spreadsheet also helps to ensure that the physical dimensions of noise barriers are calculated accurately. The following QA processes are recommended for the review of sound-level results for noise barriers:

• A graphical review of the no-barrier and with-barrier sound levels along with insertion loss by receiver is a very fast and effective way to determine if trends are appropriate and to spot any outliers. Barrier-insertion loss values generally decrease with increasing distance from the barrier and toward the ends of the barrier. In concert with that trend, with-barrier sound levels may not change very much with increasing distance from the barrier for a fairly broad area behind the barrier.
• All else being equal, increases in receiver elevation behind a barrier will result in lower insertion loss values than at other nearby receivers with lower elevation. The converse is also often true, where lower elevation receivers will usually have higher insertion loss values than surrounding receivers. This trend can be reversed in cases with elevated roadways where edge-of-pavement shielding is significant for lower-elevation receivers, already reducing noise levels. Observing the trend in no-barrier sound levels will help identify these situations.
• When reviewing different barrier designs, higher and longer barriers should result in lower with-barrier sound levels and increased insertion loss, unless other roadway sources behind the barrier become the dominant sources of noise at those receivers.

Noise Study Report Guidance and Sample Checklists

The QA processes for noise analysis reports include recommended content and level of detail appropriate for the type of study and scale of the noise analysis report. This section provides sample checklists designed to assist acoustical consultants and design engineers in the preparation of environmental noise studies and design reports prepared for SHAs. The sample checklists provide:

1. Additional information on elements to be included in noise studies that are not covered in the SHA's Policies and Procedures manual,
2. Detailed lists of the sections and contents required for noise study reports prepared for environmental document studies under the National Environmental Protection Act (NEPA) and/or applicable state environmental laws and regulations, and
3. Detailed lists and contents of reports prepared to document the results of a noise abatement design study.

The following paragraphs describe some of the elements that need to be included in SHA noise study reports (corresponding sample checklists are discussed in the next two sections). There are two fundamentally different types of noise studies and reports that are conducted for an SHA.

The first type of noise study report contributes to and supports environmental documents under NEPA and/or applicable state environmental laws and regulations, such as Environmental Assessments (EAs) and Environmental Impact Statements (EISs). These Type I studies are conducted in conjunction with a roadway improvement project. The purpose of these studies is to evaluate potential noise impacts from the proposed project, and to determine if noise abatement to mitigate those impacts would be feasible and reasonable according to FHWA and SHA policy. Portions and/or conclusions from these reports are used in the body of the Affected Environment and Environmental Consequences sections of environmental documents such as EAs and EISs. The complete noise technical report is published as an appendix to the environmental document, and is reviewed by state and federal agencies and often by members of the public through online access or at public hearings.

The second type of noise study produces a Noise Abatement Design Report. This type of study evaluates the feasibility and reasonableness of noise abatement measures and develops the acoustical design parameters for those measures. A noise abatement design study may be conducted either subsequent to an environmental document noise study, during the design phase of a Type I project, or as part of a separate Type II noise abatement project. In this latter case, the SHA often conducts a study that is a preliminary evaluation of the feasibility and reasonableness of noise abatement along the facility of interest or across the entire system. Such preliminary studies typically do not include detailed acoustical design information. In these cases, if the noise abatement measure(s) would qualify for construction, according to the state's Type II policy, a more comprehensive noise abatement design study is conducted with a more detailed noise model.

These studies report the acoustical design details of the noise abatement measures. The reports are used to assist in public involvement and to help survey public opinion on the noise abatement measures under consideration for their neighborhoods. The reports also are used by engineers to design the barriers and develop the plans and specifications for construction. Customarily, one Noise Abatement Design Report is produced for each noise barrier being evaluated, unless two or more barriers are being evaluated together as part of a system for one Common Noise Environment with one cost-effectiveness metric. For projects with several separate noise barriers, after each barrier and its report are submitted to the SHA and then reviewed and finalized, an overall barrier summary report may be produced that includes all of the separate Noise Abatement Design Reports as well as a discussion of the public involvement process.

The sample checklists discussed in the following sections provide general guidance for organizations (SHAs, engineering firms, acoustical consulting firms, etc.) that are considering the use of checklists as a means to achieve quality assurance. At the time of this report, a few SHAs have implemented checklists for the production of noise study reports. The highway analyst is encouraged to contact the noise specialist at the SHA at the outset of a project to see if checklists are being used and to request copies, as necessary.

Additional resources for the preparation of noise analysis reports are provided at the end of this chapter. See the SHA noise analysis policies and procedures guidance documents, as well as FHWA's Highway Traffic Noise: Analysis and Abatement Guidance document^[37] for more information.

Sample Checklist for Noise Study Reports Supporting Environmental Documents

A sample checklist for noise study reports supporting environmental documents is provided in Appendix G. The checklist includes the sections of the report that are to be included, with check boxes for major sections with further explanation about the contents of those sections.

The checklist is to be completed by the report preparer and submitted with the report to the project manager/supervisor for review and signature. The signed checklist may be submitted with the report to the SHA for review.

Sample Checklist for Noise Abatement Design Reports

A sample checklist for noise abatement design reports is provided in Appendix H. The checklist includes the sections of the report that are to be included, with check boxes for the elements. One Noise Abatement Design Report customarily is produced for each noise barrier evaluated, unless two or more barriers are being evaluated together as part of a system for one Common Noise Environment with one cost-effectiveness metric. For projects with several separate noise barriers, after each barrier and its report are finalized, an overall barrier summary report may be produced that includes all of the separate Noise Abatement Design Reports.

The checklist is to be completed by the report preparer and submitted with the report to the project manager/supervisor for review and signature. The signed checklist should be submitted with the report to SHA for review.

Additional Resources for Noise Study Report Guidance and Checklists

Many SHAs have developed suggested report outlines and checklists much like those presented in the previous section. This section of the report provides information on and links to some SHA resources thought to be of greatest potential value.

• VDOT has developed what may be the most comprehensive noise study report guidance document and checklist available in the U.S. The guidance document includes substantial detail on the contents of reports including example graphics. That checklist is provided in Appendix I of this document. Both the “Noise Report Guidance Accountability Checklist” and “Noise Report Development Guidance Document” are available for download at: http://www.virginiadot.org/projects/pr-noise-walls-about.asp.
• The California DOT (Caltrans) Technical Noise Supplement (TeNS) document provides much insightful guidance on many aspects of highway noise analysis and abatement, including reporting. Section 6 of the TeNS document is on the Noise Study Report and provides an outline followed by detailed information on what should go in each section. It includes examples of the various tables of results that go in the reports. The TeNS document is available at: http://www.dot.ca.gov/hq/env/noise/.
• FDOT has prepared the “Traffic Noise Modeling and Analysis Practitioners Handbook” to assist analysts in the prediction of existing and future traffic noise levels and the evaluation of noise barriers with the overarching goal to provide consistent, predictable, and repeatable noise studies. The FDOT handbook was published in 2015 and is available on the following webpage: http://www.fdot.gov/environment/publications.shtm.
• Oregon DOT provides supplemental guidance on reporting including an outline for noise study reports (NSRs) followed by separate NSR QC and reviewer's Checklist in Appendix I of its guidance document. The QA/QC policy is in Section 10.4. The document is available at: https://www.oregon.gov/ODOT/GeoEnvironmental/Docs_Environmental/Noise-Manual.pdf.
• Michigan DOT has developed outlines of both noise study reports for environmental documents and for noise barrier design studies, with details on table headings and what is needed in the noise study graphics. They are given in Section 7.0 of its noise guidance document at: https://www.michigan.gov/documents/mdot/MDOT_HighwayNoiseAnalysis_and_AbatementHandbook_358156_7.pdf.
• Minnesota DOT's 2011 guidance document, Appendix D, provides an outline with additional guidance on noise report content, including an example sound-level table. It is available at: http://www.dot.state.mn.us/environment/noise/index.html.
• North Carolina DOT (NCDOT) provides a detailed discussion of the reporting requirements in Section 12 of its guidance document, including example tables. NCDOT's reporting requirements are available at: https://connect.ncdot.gov/resources/Environmental/PDEA%20Procedures%20Manual%20Documents/2011%20NCDOT%20Traffic%20Noise%20Analysis%20and%20Abatement%20Manual.pdf
• Washington State DOT has prepared a checklist for noise study reports and a very complete Word template for reports. The template includes much of the language common to all reports, as well as tables formatted for results that go in different sections of the report. Both the checklist and template are available at: http://www.wsdot.wa.gov/environment/technical/disciplines/air-quality-noise-energy/policies.

^[25] U.S. Department of Transportation, Federal Highway Administration, “Highway Traffic Noise: Analysis and Abatement Guidance,” FHWA-HEP-10-025, December 2011. Available at: http://www.fhwa.dot.gov/environment/noise/regulations_and_guidance/

^[26] National Cooperative Highway Research Program, “NCHRP Report 791: Supplemental Guidance on the Application of FHWA's Traffic Noise Model (TNM),” 2014. Available at: http://onlinepubs.trb.org/onlinepubs/nchrp/nchrp_rpt_791.pdf

^[27] International Organization for Standardization, “Selection and use of the ISO 9000 family of standards,” 2009.

^[28] ISO 9001, “Quality management systems - Requirements,” Fourth Edition, corrected version, 2009-07-15.

^[29] See the electronic version of the New York State Department of Transportation “Highway Design Manual” available at https://www.dot.ny.gov/divisions/engineering/design/dqab/hdm?nd=nysdot.

^[30] The National Geodetic Survey (NGS) is planning to replace NAD 83 and NAVD 88 with new horizontal and vertical datums in 2022. For more information and to track the progress of this effort, see the NGS web site at https://www.geodesy.noaa.gov/datums/newdatums/index.shtml.

^[31] According to ESRI's on-line GIS dictionary (http://support.esri.com/en/) metadata is defined as “information that describes the content, quality, condition, origin, and other characteristics of data or other pieces of information. Metadata for spatial data may describe and document its subject matter; how, when, where, and by whom the data was collected; availability and distribution information; its projection, scale, resolution, and accuracy; and its reliability with regard to some standard.”

^[32] Users should check the Terms and Conditions of Use for the proper use of services and materials obtained or derived from such software applications.

^[33] Florida Department of Transportation, “Traffic Noise Modeling and Analysis Practitioners Handbook,” Environmental Management Office, May 5, 2015. Available at: http://www.fdot.gov/environment/pubs/Traffic%20Noise%20Modeling%20and%20Analysis%20Practitioners%20Handbook%20-%20January%202016%20Version.pdf.

^[34] Florida Department of Transportation, “Project Traffic Forecasting Handbook,” 2014. Available at: http://www.fdot.gov/planning/statistics/trafficdata/ptf.pdf

^[35] Florida Department Transportation, “Project Traffic Forecasting,” Topic No. 525-030-120-h, effective April 17, 2012. Available at: http://www.fdot.gov/planning/statistics/tmh/project_traffic_forecasting_proc.pdf

^[36] Virginia Department of Transportation, “Highway Traffic Noise Impact Analysis Guidance Manual,” Version 6, updated July 14, 2014. Available at: http://www.virginiadot.org/projects/resources/noisewalls/Highway_Traffic_Noise_Impact_Analysis_Guidance_Manual.pdf

^[37] “Highway Traffic Noise: Analysis and Abatement Guidance,” Federal Highway Administration, U.S. DOT, June 2010, revised January 2011. http://www.fhwa.dot.gov/environment/noise/regulations_and_guidance/analysis_and_abatement_guidance/revguidance.pdf