The research conducted under this project developed draft guidelines for nighttime road work to improve safety and operations and formulated procedures to facilitate making decisions about undertaking nighttime work. Additional work to enhance the guidelines and conduct additional case studies was performed under NCHRP Project 17-17(2).

Work zones pose safety problems for both motorists and workers. While work zones result in significant amounts of congestion and associated delay, lead to accidents and related losses, cause adverse impacts on communities and business, and increase driver frustration, the need to construct new highway facilities, preserve existing roadways, and perform maintenance make work zones unavoidable. Growth in traffic volume has led many agencies to defer road work activities to off-peak hours to avoid congestion. Nighttime work, however, raises additional safety problems. Some guidance and minimum requirements for dealing with these situations are provided in the Manual on Uniform Traffic Control Devices (MUTCD), but these are not considered sufficient for the planning, design, implementation, and operation of road work at night. Also, no procedures are available that can be readily applied to provide a systematic assessment of the advantages and disadvantages of nighttime work for a specific project.

The objectives of the research were to (1) develop guidelines for nighttime road work to improve safety and operations and (2) formulate procedures to facilitate making decisions about undertaking nighttime work.