Based on the survey results, for agencies using pavement markings in advance of the toll lanes within a conventional plaza, the tapered chevron and gore taper pattern are most commonly used. Pavement markings provide the agencies with a means of effectively extending the toll lanes to require a more timely lane selection by the user while reducing the incident of maneuvering and lane changes within the plaza queue zone. As stated above, pavement markings are also used by some agencies to indicate the collection mode in the toll lane at the end of the approach lane channelized by pavement markings. Pavement marking materials most frequently used, listed in the order of durability and highest cost are: preformed tape, thermoplastic coating epoxy paint and reflective paint. Pavement marking colors other than white and yellow have been used to distinguish lanes, particularly ETC dedicated lanes. For example, the ETC dedicated lanes on the New Jersey Turnpike use purple and white colored pavement markings to delineate the ETC express lanes. As an example of lane guidance, TCA distinguishes ETC and cash lanes with pavement markings primarily for use when fog significantly reduces visibility of overhead signs.
Impact attenuators have been installed by the many toll road agencies and to a lesser extent by toll bridge agencies at the front of the conventional plaza toll islands and barriers. While an impact attenuator provides protection to the user when approaching any of the conventional plaza toll lanes, the manual toll island impact attenuators also provides critical protection for the attendant operating the tollbooth collection equipment. Even with mass concrete protection commonly constructed in conjunction with the island in front of the toll booth, a properly designed energy absorbing device offers additional protection, particularly in the case of errant trucks. The design length of the impact attenuator is based on the size and speed of vehicles the impact attenuator could encounter during its design life. The majority of impact attenuators installed are retractable, multi-sectional guardrails that increase resistance as the front sections of the attenuator collapse and move toward the island, usually on a track anchored to the pavement. Other similar attenuator designs and associated materials have been used based on the same theory of operation. Chapter 4 of the Roadside Design Guide should be referenced for additional information on this topic.
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