AASHTO-FHWA

Agreement

Proposed By
AASHTO 350 Task Force On NCHRP 350 Implementation
July 1, 1998

AASHTO 350 TASK FORCE PARTICIPANTS

AASHTO 350 Implementation Task Force
Summary of Implementation Issues by Hardware Type

Safety Hardware Type NCHRP Report 350 Implementation Dates1 and Caveats Work to be Done
Use in New Installations2 3R Projects 3 System-wide Replacement
Longitudinal Barriers: Guardrails, Bridge Railings, and Median Barriers October 1, 1998 4
(Except weak-post w-beam system) 		October 1, 1998 4
(Replacement of existing hardware meeting 230 is not required) 		Not required.

- Test MB4 (SGM06b)
- Test MB9 (SGM09c)
- Test weak-post w-beam system, G2 (SGR02)
- Test G9 wood post (SGR09c)

Guardrail to Bridge Rail Transitions October 1, 20025
(Oct 1, 1998 meet 230) 		October 1, 20025
(Replacement of existing hardware meeting 230 is not required) 		Not required. - Develop and test new transition designs to meet 350.
Guardrail Terminals October 1, 1998
(Except cable guardrail terminals6)		 October 1, 1998
(Replacement of existing hardware not meeting 350 is required) 		Not required beyond FHWA memo of 29 Sept. 947.

- Develop and test cable guardrail terminal
- Test ELT
- Test WyBET

Crash Cushions October 1, 1998 October 1, 1998
(Replacement of existing hardware meeting 230 is not required) 		Not required. - Test steel drum system.
Work Zone Category I Devices8 October 1, 1998
New devices purchased after 1 Oct 98 must comply to 3509.
(Agencies can phase out existing devices as they complete their normal service life) 		October 1, 1998
New devices purchased after 1 Oct 98 must comply to 3509.
(Agencies can phase out existing devices as they complete their normal service life) 		Not required. None.
Work Zone Category II Devices10

October 1, 2000
New units purchsed after 1 Oct 00 must comply to 35011.
(Agencies can phase out existing devices as they complete their normal service life)

October 1, 2000
New units purchsed after 1 Oct 00 must comply to 35011.
(Agencies can phase out existing devices as they complete their normal service life) 		Not required. - Crash test existing devices11
Work Zone Category III Devices12: Devices LIsted in Category II but Having Masses > 45 kg "expected to cause significant occupant velocity change" October 1, 2002
Barriers with joints that fail to transfer tension and moment from segment to another must be updated by Oct 1, 2000 New units purchased after Oct 1, 2002 shall comply with 350. (Agencies can phase out existing devices as they complete their normal service life, except that barriers with joints that fail to transfer tension and moment from segment to another will not be acceptable after Oct 1, 2000, unless demonstrated to be crashworthy 13) 		October 1, 2002
Barriers with joints that fail to transfer tension and moment from on segment to another must be updated by Oct 1, 2000 New units purchased after Oct 1, 2002 shall comply with 350. (Agencies can phase out existing devices as they complete their normal service life, except that barriers with joints that fail to transfer tension and moment from segment to another will not be acceptable after Oct 1, 2000, unless demonstrated to be crashworthy 13)		 Required afeter 1 Oct 02 for devices that have not been demonstrated to be crashworthy13 will not be acceptable

- Crash test existing devices
- Develop new or revised devices

Work Zone Category III Devices: Truck-Mounted Attenuators & WZ Crash Cushions New units purchased after 1 Oct 98 must comply to 350. (Agencies can phase out existing TMAs and WZ crash cushions as they complete their normal service life.) New units purchased after 1 Oct 98 must comply to 350. (Agencies can phase out existing TMAs and WZ crash cushions as they complete their normal service life.) Not required. None.
Work Zone Category IV Devices15 Delayed16 Announcement of an implementation date will be made by 1 Oct 00. Delayed16 Announcement of an implementation date will be made by 1 Oct 00. Decision delayed - Develop new designs that meet 350.
Breakaway Devices 17 October 1, 199817 October 1, 199817 Not required None.
Miscellaneous Hardware18 Delayed19 Announcement of an implementation date will be made by 1 Oct 00. Delayed19 Announcement of an implementation date will be made by 1 Oct 00. Not required - Develop and test new designs to meet 350.

Notes:

  1. Date given is the date a construction project under which a feature is to be installed is advertised for bids or the date a feature is to be installed by transportation agency or utility company maintenance or force account workers.

  2. A new installation of a feature occurs when one is installed where none exists. (A transportation agency shall define when extensions, relocation, adjustments or major repairs to a feature constitute a new installation.)

  3. The general rule is that all permanent safety features on new construction and 3R projects should meet current criteria unless a design exception is obtained. The intention here, and in Note 2, is to continue this rule. However, features that meet the acceptance requirements recommend in NCHRP Report 230, at the discretion of the responsible transportation agency, may remain in place. The preferred treatment of features that must be moved, reconstructed, or extended because of a changed roadway grade, width, or other condition or must be rebuilt because of crash damage is to bring them to current criteria. Nevertheless, a transportation agency, at its discretion, may retain or extend "in-kind" an existing feature meeting the acceptance requirements in NCHRP Report 230. (The FHWA's guidance on guardrail terminal replacement is given in its memorandum cited in Note 7 below.)

  4. Full acceptance of this date is contingent upon successful completion and FHWA acceptance of certification tests for the weak-post w-beam guardrail system at Test Level 3. (The weak-post w-beam guardrail length-of-need had met Test Level 2.) These tests are being conducted by Penn State and should be completed by July 1998. If difficulties are encountered, consideration may be given to an exception for weak-post w-beam systems. It should also be pointed out that the turned-down terminal usually used with this system has not met Report 230 requirements. The crash testing histories for bridge railings differ from those of other longitudinal barriers. For information on acceptable bridge railings, see FHWA memorandum from Chief, Federal-aid Division, dated May 30, 1997, Subject: Action: Crash Testing of Bridge Railings.

  5. As of May 1998, steel- and wood-post versions of one style w-beam-to-shaped concrete parapet transition have each qualified under Report 350 acceptance criteria. Efforts are underway to qualify other transitions.

  6. Full acceptance of this date is contingent upon successful completion and FHWA acceptance of certification tests for the cable guardrail end treatment. Funding is available for two tests of the New York State DOT cable guardrail terminal. It is uncertain if this level of testing will be sufficient or that the testing can be complete to meet the October 1998 implementation date. If difficulties are encountered, it may be necessary to provide some type of exception for this type of system. There are no proven Report 230 qualified cable guardrail terminals. Continued use of existing designs until a Report 350 qualified terminal is available should be supported by a record of acceptable field performance.

  7. FHWA Executive Director to FHWA Regional Administrators and Federal Lands Program Administrator, Subject: Action: Traffic Barrier Safety Policy Guidance, dated September 29, 1994.

  8. Category I currently includes plastic cones, drums, and tubes without attachments such as signs or warning lights (see FHWA July 25, 1997 memo 1997, FHWA Director, Office of Engineering, to FHWA field offices, Subject: Action: Identifying Acceptable Highway Safety Features.)

  9. Vendors can self-certify Category I devices by meeting the criteria in Attachment A, Page 8, of the FHWA memo of July 25, 1997.

  10. Category II includes portable sign stands (with signs), type-1, -2, & -3 barricades, vertical panels, intrusion alarms, and other work zones devices under 45 kg. (See FHWA memo of July 25, 1997 cited in note 8)

  11. Efforts should be made to allow certain classes of devices in Category II to be reclassified as Category I to allow self-certification. Vendors can self-certify Category I devices by meeting the criteria in the FHWA memo cited in Note 8.

  12. Category III covers traffic control devices with masses greater that 45 kg. Some portable sign support and sign combinations failed to met Report 350 acceptance requirements and others, such as those incorporating motor vehicle axles as supports, can be expected to fail. These should be phased out of service soon unless they are modified to make them crashworthy. This category also includes portable temporary barriers, work zone crash cushions, and truck-mounted attenuators covered separately in this table. (See FHWA memo of July 25, 1997 cited in note 8). The cited FHWA memorandum discusses reduce test instrumentation. The Report 350 suggests this reduced instrumentation applies to the testing of freestanding devices with masses < 45 kg. Testing has indicated that this criterion is overly conservative. Efforts are underway to develop more appropriate testing and instrumentation guidelines for these devices. Further instruction on this will be forth coming from FHWA Office of Engineering.

  13. A barrier will be considered crashworthy if (a) it has been crash tested and met the acceptance requirements proposed in either NCHRP Reports 230 or 350 or (b) it is a barrier with one of the five joints listed as "Tested and Operational Connections" starting on page 9-3 of the 1996 AASHTO Roadside Design Guide or (c) if and Engineering Study of in-service performance demonstrate the barrier will provide the performance requirements of the site where it is to be used.

  14. Two "F-shape" portable concrete barriers have qualified under the acceptance criteria in Report 350.

  15. Category IV includes work zone traffic control equipment such as arrow panels, variable message boards, portable traffic signals, and portable lighting equipment. (See FHWA memo of July 25, 1997 cited in note 8)

  16. This delay is to allow time to conceive and evaluate alternative measures for making these devices crashworthy, to examine the use and crash histories of existing devices, and to review and, if needed, develop safer, cost-effective strategies for the replacement of these devices that will accomplish providing motorists with needed information for driving in work zones.

  17. Breakaway support hardware previously found acceptable under the breakaway requirements of either the 1985 or 1994 editions of the AASHTO Standard Specifications for Structural Supports for Highway Sign, Luminaries and Traffic Signals are acceptable under the NCHRP Report 230 or 350 guidelines. The July 25, 1997, FHWA memorandum cited in the Note 8 exempts utility poles and signal supports from the Report 350 requirements. However, where breakaway utility poles or traffic signal supports are practical they should be used.

  18. Miscellaneous hardware items identified as warranting special consideration for implementation timing are short-radius guardrail returns, the "bullnose" guardrail terminal, guardrails over low-fill culverts, guardrail curb combinations, the w-beam-thrie-beam guardrail transition, and culvert end grates.

  19. The indicated delay is to provide time to access efforts underway and, if needed, to adjust those effort or initiate new efforts to provide crashworthy versions of the identified miscellaneous hardware items. It is believed that it is possible, in the near future, to complete the development and testing of several miscellaneous devices needed by the states. The short-radius guardrail and bull-nose treatment can meet 350 through similar modifications. A long span guardrail for low-fill culverts is believed to be close to being passed. The guardrail connected to the culvert, short-radius guardrail, and culvert grates can be solved, but there is no known funding for these efforts. Testing of guardrail adjacent to curbs is underway and it is expected that designs meeting 350 will result.

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