Section 625.4 - Standards, policies, and standard specifications(a)Roadway and appurtenances.(1) A Policy on Geometric Design of Highways and Streets, AASHTO (incorporated by reference; see paragraph (d) of this section).(2) A Policy on Design Standards-Interstate System, AASHTO (paragraph (d) of this section).(3) The geometric design standards for resurfacing, restoration, and rehabilitation (RRR) projects on NHS highways shall be the procedures or the design criteria established for individual projects, groups of projects, or all RRR projects in a State, and as approved by FHWA. The RRR design standards shall reflect the consideration of the traffic, safety, economic, physical, community, and environmental needs of the projects. If a State does not adopt design procedures or criteria for RRR projects as approved by FHWA, the standards listed in paragraphs (a)(1) and (2) shall apply.(4) Location and Hydraulic Design of Encroachments on Flood Plains, refer to 23 CFR part 650, subpart A.(5) Procedures for Abatement of Highway Traffic Noise and Construction Noise, refer to 23 CFR part 772.(6) Accommodation of Utilities, refer to 23 CFR part 645 , subpart B.(7) Pavement Design, refer to 23 CFR part 626.(b)Bridges and structures.(1) For existing bridges originally designed to any edition of the AASHTO Standard Specifications for Highway Bridges, modifications may be designed to the Standard Specifications for Highway Bridges, 17th Edition, AASHTO, 2002 (incorporated by reference; see § 625.4(d) ), or to the standards and specifications that are listed in § 625.4(b) .(2) AASHTO LRFD Bridge Construction Specifications (paragraph (d) of this section).(3) AASHTO LRFD Bridge Design Specifications (paragraph (d) of this section).(4) AASHTO LRFD Movable Highway Bridge Design Specifications (paragraph (d) of this section).(5) AASHTO/AWS D1.5M/D1.5 Bridge Welding Code (paragraph (d) of this section).(6) AWS D1.4/D1.4M Structural Welding Code-Reinforcing Steel (paragraph (d) of this section).(7) AASHTO Standard Specifications for Structural Supports for Highway Signs, Luminaires, and Traffic Signals, (paragraph (d) of this section); or AASHTO LRFD Specifications for Structural Supports for Highway Signs, Luminaires, and Traffic Signals (paragraph (d) of this section).(8) Navigational Clearances for Bridges, refer to 23 CFR part 650 , subpart H.(9) AWS D1.1/D1.1M Structural Welding Code-Steel (paragraph (d) of this section).(c)Materials.(1) General Materials Requirements, refer to 23 CFR part 635 , subpart D.(2) Quality Assurance Procedures for Construction, refer to 23 CFR part 637 , subpart B.(d)Documents incorporated by reference. The standards required in this section are incorporated by reference into this section with the approval of the Director of the Federal Register under 5 U.S.C. 552(a) and 1 CFR part 51. All approved material is available for inspection at U.S. Department of Transportation's National Transportation Library at 1200 New Jersey Avenue SE, Washington, DC 20590; (800) 853-1351 and is available from the sources indicated below. It is also available for inspection at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, email fr.inspection@nara.gov or go to www.archives.gov/federal-register/cfr/ibr-locations.html.(1) American Association of State Highway and Transportation Officials (AASHTO), 555 12th Street NW, Suite 1000, Washington, DC 20004, 1-800-231-3475, https://store.transportation.org.(i) AASHTO GDHS-7, A Policy on Geometric Design of Highways and Streets, 7th Edition, 2018.(ii) A Policy on Design Standards-Interstate System, May 2016.(iii) Standard Specifications for Highway Bridges, 17th Edition, 2002(iv) AASHTO-LRFD Bridge Construction Specifications, 4th Edition, copyright 2017.(v) AASHTO LRFD-8, LRFD Bridge Design Specifications, 8th Edition, 2017.(vi) AASHTO LRFD Movable Highway Bridge Design Specifications, 2nd Edition, 2007, with:(A) Interim Revisions, 2008,(B) Interim Revisions, 2010,(C) Interim Revisions, 2011,(D) Interim Revisions, 2012,(E) Interim Revisions, 2014,(F) Interim Revisions, 2015, and(G) Interim Revisions, 2018.(viii) AASHTO LTS-6, Standard Specifications for Structural Supports for Highway Signs, Luminaires, and Traffic Signals, 6th Edition, copyright 2013, with:(A) AASHTO LTS-6-I1, 2015 Interim Revisions to Standard Specifications for Structural Supports for Highway Signs, Luminaires, and Traffic Signals, copyright 2014,(B) AASHTO LTS-6-I2-OL, 2019 Interim Revisions to Standard Specifications for Structural Supports for Highway Signs, Luminaires, and Traffic Signals, copyright 2018, and(C) AASHTO LTS-6-I3, 2020 Interim Revisions to Standard Specifications for Structural Supports for Highway Signs, Luminaires, and Traffic Signals, copyright 2019.(ix) AASHTO LRFDLTS-1, LRFD Specifications for Structural Supports for Highway Signs, Luminaires, and Traffic Signals, 1st Edition, copyright 2015, with:(A) AASHTO LRFDLTS-1-I1-OL, 2017 Interim Revisions to LRFD Specifications for Structural Supports for Highway Signs, Luminaires, and Traffic Signals, copyright 2016,(B) AASHTO LRFDLTS-1-I2-OL, 2018 Interim Revisions to LRFD Specifications for Structural Supports for Highway Signs, Luminaires, and Traffic Signals, copyright 2017,(C) AASHTO LRFDLTS-1-I3-OL, 2019 Interim Revisions to LRFD Specifications for Structural Supports for Highway Signs, Luminaires, and Traffic Signals, copyright 2018, and(D) AASHTO LRFDLTS-1-I4, 2020 Interim Revisions to LRFD Specifications for Structural Supports for Highway Signs, Luminaires, and Traffic Signals, copyright 2019.(2) American Welding Society (AWS), 8669 NW 36 Street, #130 Miami, FL 33166-6672; www.aws.org; or (800) 443-9353 or (305) 443-9353.(i) AWS D1.1/D1.1M:2015 Structural Welding Code-Steel, 23rd Edition, copyright 2015, including Errata March 2016 (second printing).(ii) AWS D1.4/D1.4M:2011 Structural Welding Code -Reinforcing Steel, 2011.(iii) AASHTO/AWS D1.5M/D1.5: 2015-AMD1, Bridge Welding Code, 7th Edition, Amendment: December 12, 2016.(e)Additional design resources. The FHWA supports using, as design resources to achieve context sensitive designs, guides that national organizations develop from peer-reviewed research, or equivalent guides that are developed in cooperation with State or local officials, when such guides are not in conflict with Federal laws and regulations.62 FR 15397, Apr. 1, 1997, as amended at 67 FR 6395, Feb. 12, 2002; 69 FR 18803, Apr. 9, 2004; 71 FR 26414, May 5, 2006; 74 FR 28442, June 16, 2009; 80 FR 61307, Oct. 13, 2015; 83 FR 54880, Nov. 1, 2018; 87 FR 41, Jan. 3, 2022 83 FR 54880, 12/3/2018; 87 FR 41, 2/2/2022