The Federal Highway Administration (FHWA) requires that all work-zone traffic control devices used on the National Highway System (NHS) meet the evaluation criteria in NCHRP Report 350: Recommended Procedures for the Safety Performance Evaluation of Highway Features. Certain low-mass items, referred to by FHWA as Category 2 devices, must meet NCHRP Report 350 criteria if they are purchased new or fabricated after October 1, 2000. Category 2 devices include the Manual on Uniform Traffic Control Devices (MUTCD) Type I, II, and III barricades; vertical panels; and temporary sign supports. Many of the designs that meet NCHRP Report 350 criteria are proprietary and can cost considerably more than comparable shop-fabricated designs. Although the shop-fabricated devices in use are made from readily available, low-cost materials, not all designs have been properly crash tested and evaluated to permit their continued use on the NHS. Because all Category 2 work-zone traffic control devices used on the NHS must meet NCHRP Report 350 criteria, a number of nonproprietary, crashworthy work-zone traffic control devices need to be identified or developed and their plans and specifications made available to state transportation agencies. These devices need to be easily fabricated of readily available materials, be cost efficient, and meet NCHRP Report 350 crash test criteria. Under NCHRP Project 22-18, “Crashworthy Work-Zone Traffic Control Devices,” Texas Transportation Institute designed and successfully crash tested two Type III barricades with attached sign panel; three low-mounting-height, portable sign supports; and a high-mounting-height, portable sign support. In Phase I, the research team reviewed the literature and ongoing research to identify Category 2 devices that have been crash tested and conducted a survey of state and federal transportation agencies to obtain information on Category 2 work-zone traffic control devices currently being used. The focus was on identifying widely used sets of devices that have few or no nonproprietary, crashworthy designs. Based on this information, the panel selected sets of work-zone traffic control devices for investigation under Phase II. In Phase II, the research team developed several design variations for each of the device sets selected in Phase I. The designs were reviewed and prioritized by the project panel, and the prioritization served as the basis for the full-scale crash testing matrix. In addition to providing detailed drawings and specifications for the successfully crash tested systems, the report presents a description of the other design concepts for future consideration and testing. (Author/publisher) This report may be accessed by Internet users at http://gulliver.trb.org/publications/nchrp/nchrp_rpt_553.pdf
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