MASH gives uniform guidelines for crash testing of temporary and permanent highway safety devices and evaluations of crash data results.
MASH updates and replaces NCHRP Report 350. This manual is recommended for highway design engineers, bridge engineers, safety engineers, researchers, hardware developers, crash test laboratories, and others concerned with safety features used in the highway environment. Products addressed in MASH include longitudinal barriers, transitions, end terminals, crash cushions, breakaway supports, truck mounted attenuators, and work zone traffic control devices. The crash performance is judged on structural adequacy, occupant risk, and vehicle trajectory.
- All new testing will be done following MASH evaluation techniques.
- Hardware accepted under NCHRP Report 350 is appropriate for replacement and new installation. Retesting is not required.
- As of January 1, 2011, all new products must be tested using MASH crash test criteria for use on the National Highway System (NHS).
4.Significant Changes between NCHRP 350 and MASH
|Small car test vehicle||820C vehicle (1,800 lbs.)||1100C vehicle (2,420 lbs.)|
|Small car impact angle||20°||25°|
|Light truck test vehicle||2000P (4,400 lbs.)||2270P (5,000 lbs.)|
|Gating terminals and crash cushion impact angle||15°||5° - 15°|
|Variable message signs and arrow board trailers||No mention||Added to TMA crash test matrix|
|Support structure and work zone traffic control device testing||Only small car tested||Small car and light truck tested|
|Windshield damage criteria||Subjective/Qualitative||Objective/Quantitative|
|Vehicle rebound in crash cushion tests||None||Required|
5.NCHRP 350 Sunset
6.On November 12, 2015, FHWA issued a memorandum indicating that all modifications to NCHRP 350-tested devices will require testing under MASH in order to receive a Federal-aid eligibility letter from FHWA. In addition, a Federal Register Notice was also issued regarding this action. This has provided a significant step toward the implementation of MASH.
December 31, 2017 W-Beam Barriers and cast-in-place Concrete Barriers.
June 30, 2018 W-Beam Terminals
December 31, 2019 Cable Barriers, Cable Barrier Terminals, and Crash Cushions
December 31, 2019 Bridge Rails, Transitions, All other Longitudinal Barriers (including portable barriers install permanently), all other Terminals, Sign Supports, and all other breakaway hardware