Work zone activities are one of the areas with a high potential for compromised safety for workers and road users. Various measures have been taken to increase the level of safety in work zones; including the use of double fines for speeding and the application of speed displays based on radar detection. There has been an effort to improve the effectiveness and safety of flaggers by requiring the use of a stop/slow paddle for most work zone conditions, using lights on the paddle, and increasing visibility by using more reflective clothing. It has been suggested that safety in work zones could also be improved with the application of more automated equipment which would control traffic in work zones without the use of flaggers. Other special operations in work zones require the use of elevated platforms or bucket trucks to perform work over or near traffic that create special safety problems. Another work zone safety issue of importance that would benefit from more specific guidance is routine short duration and mobile maintenance operations such as roadway surface patching. The objectives of this research included the following: 1) evaluation of measures and procedures that will alter or control the speed of motorists in work zones, 2) investigate the feasibility of using automated equipment to replace flaggers in work zones, 3) develop policy and guidelines for use of elevated platforms near traffic, and 4) evaluate the safety issues associated with mobile and short-term work activities. In an attempt to determine the effectiveness of various speed control measures in work zones, speed data were collected for several strategies including signs, radar displays, and police enforcement. It was determined that the largest reduction in speed can be achieved with the presence of police enforcement at the work site. The use of automated flagger devices were investigated, and it was determined that these devices have potential for application in long-term lane closures at work zone locations such as bridge deck repairs. Flashing STOP/SLOW paddles were purchased and provided to maintenance personnel for evaluation. The paddles were used by employees with mixed results in terms of their practicality and durability. Guidelines for use of aerial lifts/elevated platforms were developed, in conjunction with a typical application drawing for aerial work within an intersection. Application of the guidelines and drawing were reviewed and discussed with representatives of the Kentucky Transportation Cabinet, with one area of focus being work over an open lane of traffic. A handbook was developed to provide guidelines for traffic control in short duration and mobile work zones. Areas of emphasis were the following: 1) Work Duration, 2) Major Traffic Control Considerations, 3) Fundamental Principles, 4) Guidance, Options, and Support for Short Duration or Mobile Operations, 5) Component Parts of a Temporary Traffic Control Zone, 6)Tapers, 7) Flaggers, and 8) Arrow Panels. Typical application diagrams were developed for various types of short duration and mobile work activities.
Available at: http://works.bepress.com/eric_green/55/