Practices for Ensuring the Smoothness of Concrete Bridge Decks (2022)

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60 A P P E N D I X B Responses from the State DOT Survey 1. Does your agency have a straightedge or a rolling straightedge-based criterion for checking the surface finish of a newly placed concrete bridge deck after the concrete has hardened? (If the answer to Question 1 is No, go to Question 5). Response State DOT Yes Alabama, Alaska, Arkansas, Colorado, Connecticut, Delaware, Florida, Georgia, Hawaii, Illinois, Iowa, Kansas, Kentucky, Louisiana, Maine, Maryland, Massachusetts, Michigan, Minnesota, Mississippi, Missouri, Montana, Nevada, New Jersey, New Mexico, New York, Ohio, Pennsylvania, Rhode Island, Texas, Utah, Vermont, Washington, Wyoming No Indiana, Nebraska, New Hampshire, South Carolina, Tennessee 2. What method is used to check for the straightedge or rolling straightedge criterion? (Indicate all that apply.) Response State DOT Straightedge Alabama, Alaska, Arkansas, Colorado, Connecticut, Delaware, Florida, Georgia, Hawaii, Illinois, Iowa, Louisiana, Maine, Maryland, Massachusetts, Michigan, Minnesota, Mississippi, Montana, Nevada, New Mexico, New York, Pennsylvania, Texas, Utah, Vermont, Washington, Wyoming Rolling straightedge Delaware, Kansas, Kentucky, Missouri, Ohio Rolling straightedge simulation performed on data collected with a walking profiler (e.g., SurPRO) New Jersey Rolling straightedge simulation performed on data collected with an inertial profiler Ohio, Rhode Island

Responses from the State DOT Survey 61   3. What is the length of straightedge or wheel spacing of the rolling straightedge that is used? Response State DOT 10 foot Alabama, Alaska, Arkansas, Colorado, Connecticut, Delaware, Florida, Georgia, Hawaii, Kansas, Kentucky, Louisiana, Maine, Maryland, Massachusetts, Michigan, Minnesota, Mississippi, Missouri, Montana, New Jersey, New Mexico, New York, Ohio, Rhode Island, Texas, Utah, Vermont, Washington, Wyoming 12 foot Nevada, Pennsylvania 16 foot Illinois Other, please specify: No responses 4. What is the straightedge criterion that is required in the direction parallel to the travel direction? (Note: Provide the value that is used when the final riding surface is concrete, as some DOTs have different requirements if the concrete deck is to be overlaid with asphalt.) Response State DOT Deviation less than 1/8 inch from bottom of straightedge Alabama, Alaska, Arkansas, Connecticut, Georgia, Iowa, Kansas, Kentucky, Louisiana, Maine, Maryland, Michigan, Minnesota, Mississippi, Missouri, New Jersey, Ohio, Texas, Vermont, Washington Deviation less than 3/16 inch from bottom of straightedge Colorado, Florida, Hawaii, Illinois, Montana, New Mexico, Pennsylvania, Utah Deviation less than 1/4 inch from bottom of straightedge Delaware, Massachusetts, Nevada, Rhode Island, Wyoming Other, please specify: New York - 3/8 inch

62 Practices for Ensuring the Smoothness of Concrete Bridge Decks 5. Does your agency have a specification for new concrete bridge surfaces that is based either on Profile Index or International Roughness Index (IRI) or Half-Car Roughness Index? (If the answer to Question 5 is no, go to Question 23) Response State DOT No (Note 1) Arkansas, Alaska, Colorado, Connecticut, Delaware, Indiana, Kansas, Kentucky, Louisiana, Maine, Maryland, Massachusetts, Missouri, Montana, New Hampshire, New Jersey, New Mexico, New York, Pennsylvania, Rhode Island, Texas, Vermont, Washington, Wyoming Yes (Note 2) Alabama, Florida, Georgia, Hawaii, Illinois, Iowa, Michigan, Minnesota, Mississippi, Nebraska, Nevada, Ohio, South Carolina, Utah, Tennessee Note 1: Louisiana DOT has developed a draft IRI-based specification that has not been finalized and published. Information in the draft specification is used to answer the next questions. Note 2: Alabama DOT uses the straightedge to check for smoothness. The IRI-based specification was used only in one project. Comments: • New Hampshire DOT: In New Hampshire, 99% of bridges receive an asphalt overlay. • Ohio: If the IRI specification is not used a 10-ft. rolling straightedge criterion is used. 6. What are the limits to which the smoothness specification is applied? Response State DOT Bridge deck only Alabama, Georgia, Michigan Bridge deck and approach slabs Florida, Hawaii, Iowa, Louisiana, Michigan,Mississippi, Nebraska, South Carolina Bridge deck, approach slab, and a specified length of roadway beyond the approach slab if the pavement is constructed under the same contract Illinois, Nevada, Ohio, Tennessee, Utah • Nevada DOT: Within 50 feet of the leading edge of the bridge and within 50 feet of the trailing edge of the bridge.

Responses from the State DOT Survey 63   • Ohio DOT: A bridge encounter is defined as 25 ft. of pavement on either side of the structure and everything in between (i.e., deck and approach slabs). • Utah DOT: 25 ft. of pavement on either side of the approach slabs. 7. Does the applied smoothness specification vary based on the functional class (i.e., primary, secondary, etc.) of the roadway? Response State DOT No Alabama, Florida, Georgia, Hawaii, Illinois, Iowa, Louisiana, Minnesota, Mississippi, Nebraska, Nevada, Ohio, South Carolina, Utah Yes Michigan, Tennessee Comments: • Michigan DOT and Tennessee DOT: Based on the speed limit. • Illinois DOT: Profilograph specification is applied to bridges that are diamond ground. 8. Does the smoothness specification vary for different types of concrete bridge deck construction methods (e.g., inclusion of armored expansion joints)? Response State DOT No Alabama, Florida, Georgia, Hawaii, Illinois, Iowa, Michigan, Minnesota, Mississippi, Nebraska, Nevada, South Carolina, Tennessee, Utah Yes Louisiana, Ohio Comments: • Louisiana DOT: The criteria for localized roughness (IRI) using a sliding base length will have a higher value for 25-ft. segments containing a joint. • Ohio DOT: Different localized roughness (IRI) values used for segments that contain a joint.

64 Practices for Ensuring the Smoothness of Concrete Bridge Decks 9. Does the concrete bridge deck need to meet a minimum length in order for the smoothness specification to be applied? Response State DOT No Alabama, Georgia, Hawaii, Iowa, Michigan, Mississippi, Nebraska, Nevada, Ohio, Tennessee, Utah Yes Florida – 100 ft., Illinois – 150 ft., Louisiana – 300 ft., Minnesota – 2500 ft., South Carolina – 100 ft. 10. Who collects the smoothness data on the concrete bridge deck immediately after construction to assess the smoothness of the bridge deck? Response State DOT DOT Georgia, Hawaii, Michigan, Minnesota, Nebraska, South Carolina, Tennessee Contractor constructing the bridge Florida, Illinois, Iowa, Louisiana, Nevada, Ohio, Utah Third party selected by the contractor Alabama, Mississippi Third party selected by the DOT No responses Comment • Alabama DOT: Contractor selects from a list of testing companies that are pre-approved by the DOT. • Nevada DOT: The contractor selects a third party to perform measurements if the contractor does not have the equipment. 11. If the smoothness data on the concrete bridge deck is collected by the contractor constructing the bridge, a third party hired by the contractor, or a third party hired by the DOT, who performs verification testing? Response State DOT DOT Illinois, Iowa, Louisiana, Nevada, Ohio, Utah A different third party selected by the DOT No Responses

Responses from the State DOT Survey 65   Comment: • Mississippi DOT and Florida DOT: DOT personnel monitor the data collected by the contractor. 12. What is the time frame for collecting the smoothness data on the concrete bridge deck after construction? Response State DOT Within 7 days after concrete is poured Michigan, Tennessee Within 14 days after concrete is poured Hawaii Within 7 days after the entire project is completed No responses Within 14 days after entire project is completed No responses Once a specified flexural strength is reached for concrete No responses Once a specified compressive strength is reached for concrete No responses No time period is specified Alabama, Florida, Georgia, Illinois, Louisiana, Minnesota, Mississippi, Nebraska, Nevada, Ohio, South Carolina, Utah Comment: • Iowa DOT: In Iowa, for bridge decks that are less than 100 ft. long, and when the bridge deck is constructed in a single pour, the contractor must provide the DOT the results from testing within 14 days after construction. For decks that are more than 100 feet long that are not constructed in a single pour, the results of the testing for the first pour must be provided to the DOT within five days, and on subsequent placements the contractor is required to provide the DOT results for every third placement.

66 Practices for Ensuring the Smoothness of Concrete Bridge Decks 13. Are negative or positive pay adjustments applied based on the obtained smoothness? Response State DOT No negative or positive pay adjustments are applied Alabama, Florida, Georgia, Hawaii, Illinois, Mississippi, Nebraska, Nevada, South Carolina Only negative pay adjustments applied Michigan, Minnesota, Tennessee Only positive pay adjustments applied Louisiana Negative or positive pay adjustment applied based on obtained smoothness Iowa, Ohio, Utah 14. What is the interval over which the PI or IRI is computed? Response State DOT 100 feet Hawaii, Nebraska 300 feet Florida, South Carolina 0.1 Mile (528 feet) (Note 1) Alabama, Iowa, Minnesota, Utah Entire length of bridge Georgia, Illinois, Michigan, Mississippi, Tennessee Other, please specify Louisiana – 264 ft., Nevada – Only localized roughness used, Ohio – Based on histogram distribution of localized roughness Note 1: Iowa DOT – PI is reported for the entire lane of the bridge if the bridge is 778 ft. or less. If the bridge is more than 778 feet long, the PI is reported at 0.1-mile intervals. 15. Is the smoothness specification based on PI, IRI, or HRI? (If the answer to Question 15 is IRI or HRI, go to Question 20.) Response State DOT PI Florida, Georgia, Hawaii, Illinois, Iowa, Mississippi, Nebraska, South Carolina IRI Alabama, Louisiana, Michigan, Minnesota, Nevada, Ohio, Tennessee, Utah HRI No responses

Responses from the State DOT Survey 67   16. If the smoothness specification is based on Profile Index (PI), identify all the equipment/methods that are allowed to collect the data. Response State DOT California-type profilograph Florida, Hawaii, Iowa, Mississippi, Nebraska, South Carolina Rainhart-type profilograph No Response Walking Profiler (with profilograph simulation performed on data to compute PI) No Response Inertial Profiler (with profilograph simulation performed on data to compute PI) Georgia, Illinois, Iowa Comment: • Iowa DOT: Iowa DOT allows data to be collected by a California-type profilograph or an inertial profiler and then performs a California profilograph simulation on the collected data. 17. When computing the Profile Index (PI), what blanking band is used for analysis? Response State DOT Zero blanking band Illinois, Iowa, Mississippi, 0.1-inch blanking band Georgia, Hawaii 0.2-inch blanking band Florida, Nebraska, South Carolina

68 Practices for Ensuring the Smoothness of Concrete Bridge Decks 18. What is the threshold for Profile Index (PI) below which no correction is required? (Note: If different thresholds are used for different functional classes, please provide the value used for Interstate Highways. Provide the value when the final riding surface of the bridge will be concrete, as some DOTs may have different requirements if an asphalt overlay is placed on the completed concrete surface.) Response State DOT PI not used, only bump criterion use No responses Less than 10 inches per mile Florida, South Carolina Less than 20 inches per mile No responses Less than 30 inches per mile No responses Less than 40 inches per mile No responses Less than 50 inches per mile Nebraska Less than 60 inches per mile No responses Less than 70 inches per mile No responses Less than 80 inches per mile No responses Other Georgia – Less than 15 in./mi., Illinois – Less than 25 in./mi., Iowa – Less than 22.1 in./mi., Hawaii – Less than 10 in./mi., Mississippi – Less than 65 in./mi. 19. Based on a 25-foot template used to detect bumps on profilograph data, what are the limits for bumps that need to be corrected? (Note: If different thresholds are used for different functional classes please provide the value used for Interstate highways. Provide the value when the final riding surface of the bridge will be concrete, as some DOTs may have different requirements if an asphalt overlay is placed on the concrete surface.) After this question, go to Question 22. Response State DOT Only PI used, bump criterion is not specified Hawaii Greater than 0.2 inch Georgia Greater than 0.25 inch South Carolina Greater than 0.3 inch Florida, Illinois, Mississippi Greater than 0.4 inch No response Greater than 0.5 inch Iowa Greater than 0.6 inch No response Other value, please specify Nebraska – Greater than 0.15 inch

Responses from the State DOT Survey 69   20. If the index used to evaluate smoothness is IRI/HRI, what is the mean IRI/HRI of the evaluated section (e.g., 0.1-mile length, entire bridge etc. based on DOT criterion) below which no corrections are required? (Note: If different thresholds are used for different functional classes please provide value used for Interstate highways. Provide the value when the final riding surface of the bridge will be concrete as some DOTs may have different requirements if an asphalt overlay is placed on the completed concrete surface.) Response State DOT Less than 50 in./mi. No responses Less than 60 in./mi. Minnesota Less than 70 in./mi. No responses Less than 80 in./mi. No responses Less than 90 in./mi. Utah Less than 100 in./mi. No responses Less than 110 in./mi. No responses Less than 120 in./mi. Alabama, Louisiana Other, please specify Michigan and Tennessee – Less than 130 in./mi., Nevada – Only localized roughness criterion, Ohio – Only localized roughness criterion 21. If the index used to evaluate smoothness is the IRI/HRI, how are localized roughness events detected? Response State DOT No method specified to detect localized roughness; the IRI/HRI of the specified section must be below a specified threshold No responses IRI/HRI values over a specified threshold based on a continuous 25-foot moving average IRI/HRI Alabama, Louisiana, Nevada, Ohio, Tennessee, Utah Profilograph simulation on profile data used to detect bumps Minnesota Other, please specify Michigan – Straightedge

70 Practices for Ensuring the Smoothness of Concrete Bridge Decks 22. Is the DOT’s smoothness specification available on the web? Response State DOT No Alabama, Georgia, Hawaii, Illinois, Louisiana, Minnesota, Nebraska,Nevada, South Carolina Yes Florida, Iowa, Michigan, Mississippi, Ohio, Tennessee, Utah Web links for specifications: • Florida DOT: https://fdotwww.blob.core.windows.net/sitefinity/docs/default- source/programmanagement/implemented/specbooks/january2019/files/400- 119.pdf?sfvrsn=407a14ad_2 • Iowa DOT: https://iowadot.gov/erl/current/GS/content/2428.htm • Michigan DOT: https://mdotcf.state.mi.us/public/dessssp/spss_source/20SP-501K-01.pdf • Mississippi DOT: Page 987 http://mdotportal.mdot.state.ms.us/sites/home/MDOT_Global_Forms/2017%20Standard %20Specifications%20Book.pdf • Ohio DOT: https://www.dot.state.oh.us/Divisions/ConstructionMgt/Specification Files/PN555_01152021_for_2019.pdf • Tennessee DOT: Page 550 https://www.tn.gov/tdot/tdot-construction-division/transportation-construction-division- resources/2021-standard-specifications.html • Utah DOT: Section 02701 https://drive.google.com/drive/folders/1bHZnAA5CdqvTPBy1ot8lQHwUbGr2Zkka The incentive/disincentive tables document https://docs.google.com/document/d/1Sfpofs70PFIabVOzCu4EJtDfkH_LR39S/edit

Responses from the State DOT Survey 71   23. This question pertains to the DOT’s Pavement Management System/Bridge Management System. DOTs store the roughness information of their pavement network in a Pavement Management System, with the IRI being the typical parameter that is used to define the roughness. Does the DOT’s Pavement Management System/Bridge Management System store the roughness data collected on bridges during the network level survey? (If the answer to Question 23 is No, go to Question 27.) Response State DOT No Alabama, Alaska, Colorado, Connecticut, Florida, Georgia, Hawaii, Illinois, Kansas, Maine, Massachusetts, Michigan, Minnesota, Mississippi, Montana, Nebraska, New Hampshire, New Jersey, New Mexico, New York, Pennsylvania, South Carolina, Tennessee, Texas, Utah, Vermont, Washington, Wyoming Yes, IRI or HRI used Arkansas, Connecticut, Indiana, Iowa, Kentucky, Louisiana, Missouri, Nevada, Ohio, Rhode Island Comment: • Nevada DOT: Nevada DOT stores IRI data for the bridges inadvertently because of how the IRI data for the roadways are collected. Since the profiler is run for the total length of an entire route, IRI data would be collected on the bridges. However, since the DOT does identify bridge locations in the PMS, there is no way to say the DOT is processing or storing the IRI data specifically for the purpose of using it to assess bridge roughness conditions. 24. For what length limits associated with the bridge are the roughness data stored? Response State DOT Bridge deck only Connecticut Bridge deck and approach slab Arkansas, Indiana, Kentucky, Louisiana, Missouri, Rhode Island Other, please specify Ohio and Iowa – 0.1-mile intervals Comment: • Nevada DOT: See comment for Question 23.

72 Practices for Ensuring the Smoothness of Concrete Bridge Decks 25. Does the DOT use the roughness data of bridges stored in the Pavement Management System/Bridge Management System to evaluate roughness progression of bridge decks? Response State DOT Yes No response No Arkansas, Connecticut, Iowa, Louisiana, Missouri, Nevada, Ohio Not known Indiana, Kentucky, Rhode Island 26. Does the decision tree used for managing bridges trigger treatments based on the roughness level of the bridge deck? Response State DOT Yes Ohio No Arkansas, Connecticut, Indiana, Iowa, Kentucky, Louisiana, Missouri, Nevada, Rhode Island Not known No responses 27. Does the DOT have a schedule for performing maintenance activities on bridge decks that affect the ride quality (e.g., inspecting expansion joints and approach slab and repairing if issues are found, applying surface treatments, etc.) or are problems addressed when they are reported? Response State DOT DOT has a schedule for performing maintenance activities on bridges that affect ride quality. Hawaii, Indiana, Ohio, Wyoming DOT does not have a schedule, and issues are addressed when they are reported. Alabama, Alaska, Arkansas, Colorado, Connecticut, Delaware, Florida, Georgia, Illinois, Iowa, Kansas, Kentucky, Louisiana, Maine, Massachusetts, Mississippi, Missouri, Montana, Nebraska, Nevada, New Hampshire, New Jersey, New Mexico, New York, Pennsylvania, Rhode Island, South Carolina, Tennessee, Texas, Utah, Vermont, Washington Not known Michigan, Minnesota

Responses from the State DOT Survey 73   28. What type of maintenance activities or rehabilitation activities are typically performed on bridges to maintain smoothness? (Select all that apply.) Response State DOT Repairing expansion joints Alabama, Alaska, Arkansas, Colorado, Connecticut, Delaware, Florida, Georgia, Hawaii, Illinois, Indiana, Iowa, Kentucky, Louisiana, Maine, Minnesota, Mississippi, Missouri, Montana, Nebraska, Nevada, New Mexico, New York, Ohio, Rhode Island, South Carolina, Tennessee, Texas, Utah, Vermont, Wyoming Repairing distress in approach slabs Arkansas, Colorado, Connecticut, Delaware, Florida, Georgia, Hawaii, Illinois, Indiana, Iowa, Louisiana, Maine, Minnesota, Mississippi, Missouri, Montana, Nebraska, Nevada, New Mexico, New York, Ohio, South Carolina, Tennessee, Texas, Utah, Wyoming Place an asphalt overlay Alaska, Arkansas, Colorado, Connecticut, Florida, Georgia, Illinois, Maine, Massachusetts, Missouri, Nebraska, Nevada, New Hampshire, Ohio, Rhode Island, South Carolina, Tennessee, Utah, Vermont, Wyoming Place a concrete overlay Colorado, Delaware, Georgia, Illinois, Indiana, Iowa, Kentucky, Maine, Mississippi, Missouri, Montana, Nebraska, Nevada, Ohio, South Carolina, Texas, Wyoming Place a polymer overlay Arkansas, Colorado, Delaware, Illinois, Indiana, Louisiana, Maine, Mississippi, Missouri, Nebraska, Nevada, New Hampshire, New Mexico, New York, Ohio, Rhode Island, South Carolina, Tennessee, Texas, Utah Comments: • Arkansas DOT: Placement of overlays is primarily done to address concrete failures/patches in the deck or scaling and not necessarily to address deck smoothness. • Kansas DOT: Kansas DOT does not address smoothness. If necessary, grinding will be performed on the bridge to improve smoothness. • Minnesota DOT: Spall patching is performed for maintenance. • New Hampshire DOT: The polymer overlay is only used occasionally in New Hampshire. It is only used on bare decks, which are rare in New Hampshire. • Nevada DOT: Nevada DOT has utilized all the strategies above to preserve and repair bridge decks. However, none of these practices are utilized primarily to maintain the smoothness of bridge decks.

74 Practices for Ensuring the Smoothness of Concrete Bridge Decks • New York: Partial depth repairs are performed as maintenance. • Ohio DOT: Ohio DOT has been doing in-house and contractor work to repair the ride due to settled approach slabs and approach pavements. • Texas DOT: While all the activities above are performed, they are not necessarily performed solely to maintain smoothness. • Washington State DOT: The above items are either repaired by maintenance or programmed for rehabilitation on an as-needed basis, but Washington State DOT does not base repairs and overlays on surface smoothness. 29. What type of funding mechanism is available for bridge preservation to ensure that bridges provide a smooth riding surface (e.g., repair of expansion joints, repair of approach slabs)? Response State DOT Dedicated funding provided annually to address smoothness-related issues for a specified length of bridges Hawaii, Mississippi, New Mexico, Rhode Island Dedicated funding provided annually to address smoothness-related issues on a specified number of bridges No responses No dedicated funding is provided, and issues are addressed when they are reported Alabama, Arkansas, Colorado, Connecticut, Delaware, Florida, Illinois, Iowa, Kentucky, Louisiana, Maine, Massachusetts, Missouri, Montana, Nebraska, Nevada, New Hampshire, New Jersey, Ohio, Pennsylvania, Texas, Utah, Vermont, Washington, Wyoming Not known Alaska, Georgia, Indiana, Kansas, Michigan, Minnesota, New York, South Carolina, Tennessee 30. Please provide any other comments you may have related to concrete bridge surface smoothness or further explanations to the above questions. • Connecticut DOT: Connecticut DOT typically uses asphalt overlays on the majority of our structures. In regard to concrete decks, standard specification delineates 1/8-inch deviation measured with a 10-ft. straightedge for bare decks and ¼-inch deviations measured with a 10-ft. straightedge for asphalt overlays. There is no further evaluation of smoothness. Latex modified overlays may require diamond grinding to provide appropriate finished surface following placement. Latex modified overlays are minimally

Responses from the State DOT Survey 75   used in Connecticut and therefore cannot be considered standard practice. Connecticut DOT does do smoothness testing for asphalt concrete on roadways and imposes incentives/disincentives to contractors through construction contracts that does not include bridges. Connecticut DOT collects IRI on all roadways every year for submittal to the FHWA that contains bridge data but is not included in the annual report card. Connecticut DOT does not report out on bridges alone at this time. • Massachusetts DOT: Most bridges in Massachusetts are paved with asphalt concrete. Very few bridges have exposed concrete decks. • New Hampshire DOT: New Hampshire primarily has asphalt overlay bridges. We have money dedicated to the preservation of bridges, but the goal is for repair, not smoothness. We also have pavement preservation funds. When those funds are for a road that crosses a bridge, there is coordination between Bridge Design and Highway Design regarding the pavement preservation treatment. For most concrete decks on girder bridges, the treatment is a pavement inlay, but the purpose for bridge pavement preservation is more to remove the road salt contaminated asphalt pavement and less to address rideability. • New Mexico DOT: New Mexico DOT has dedicated funding provided annually to address preservation-related issues that include topics related to smoothness. I responded in the affirmative to that question, however, the funding does not specifically note smoothness as a criterion. • Ohio DOT: Ohio DOT has been working on this issue for over the past 15 years. Our first routine specification for bridge smoothness was in spring of 2012. We very recently updated our IRI-based bridge encounter specification which is now positively and negatively pay adjusted based on resultant smoothness. No bridges have been constructed with this version of the specification. • Washington State DOT: The Washington State DOT bridge preservation program does not focus on ride quality during service but rather preservation of structures. Repair of items such as failing expansion joints, rutting, and potholes are generally programmed based on biennial inspections. Depending on the percentage of bridge deck damage noted in bridge inspections, the DOT will either program for repairs or resurfacing.

Abbreviations and acronyms used without denitions in TRB publications: A4A Airlines for America AAAE American Association of Airport Executives AASHO American Association of State Highway Officials AASHTO American Association of State Highway and Transportation Officials ACI–NA Airports Council International–North America ACRP Airport Cooperative Research Program ADA Americans with Disabilities Act APTA American Public Transportation Association ASCE American Society of Civil Engineers ASME American Society of Mechanical Engineers ASTM American Society for Testing and Materials ATA American Trucking Associations CTAA Community Transportation Association of America CTBSSP Commercial Truck and Bus Safety Synthesis Program DHS Department of Homeland Security DOE Department of Energy EPA Environmental Protection Agency FAA Federal Aviation Administration FAST Fixing America’s Surface Transportation Act (2015) FHWA Federal Highway Administration FMCSA Federal Motor Carrier Safety Administration FRA Federal Railroad Administration FTA Federal Transit Administration GHSA Governors Highway Safety Association HMCRP Hazardous Materials Cooperative Research Program IEEE Institute of Electrical and Electronics Engineers ISTEA Intermodal Surface Transportation Efficiency Act of 1991 ITE Institute of Transportation Engineers MAP-21 Moving Ahead for Progress in the 21st Century Act (2012) NASA National Aeronautics and Space Administration NASAO National Association of State Aviation Officials NCFRP National Cooperative Freight Research Program NCHRP National Cooperative Highway Research Program NHTSA National Highway Traffic Safety Administration NTSB National Transportation Safety Board PHMSA Pipeline and Hazardous Materials Safety Administration RITA Research and Innovative Technology Administration SAE Society of Automotive Engineers SAFETEA-LU Safe, Accountable, Flexible, Efficient Transportation Equity Act: A Legacy for Users (2005) TCRP Transit Cooperative Research Program TDC Transit Development Corporation TEA-21 Transportation Equity Act for the 21st Century (1998) TRB Transportation Research Board TSA Transportation Security Administration U.S. DOT United States Department of Transportation

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