That's your cue

摘要

Transportation professionals view the setting of appropriate regulatory speed limits on public roads, including those under repair or reconstruction, as an important tool in promoting safe and efficient operations. To aid this decision-making process, state highway agencies have adopted policies and procedures for determining if a reduced regulatory speed limit should be established in a work zone. Most of these policies indicate that lowering the regulatory speed limit in work zones should be avoided as much as is practical. However, in some work-zone situations, such as when workers are present in a lane closure without positive protection, a reduced regulatory speed limit may be needed. It is generally accepted that the safety of both workers and road users is improved in work zones when traffic is going slower. Logically, crashes and their resulting injuries are likely to be less severe at lower speeds. In addition, a driver traveling at a slower speed has more time to react and recover in emergency situations, should the need arise. Slower speeds also reduce wind effects of large trucks and provide workers more time to react should a vehicle intrusion occur. However, slower speeds in work zones also may reduce the roadway capacity and cause localized congestion, which in turn can increase the potential for rear-end crashes.