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| Guideline | Pavement Marking/Channelization/Impact Attenuator Guideline 1 |
| Title | Toll Island/Attenuator Pavement Markings |
| Text | Gore or chevron pavement markings should be installed immediately in front of the impact attenuator, as applicable, or the toll island. |
| Commentary | While winter visibility and maintenance expenses are important considerations, the safety and operational benefits of reducing space for unsafe lane changes and maneuvering within the plaza and highlighting the areas of the plaza queue zone that do not lead to a toll lane justify the recommended pavement markings |
| Guideline | Pavement Marking/Channelization/Impact Attenuator Guideline 2 |
| Title | Lane Separation using Pavement Marking |
| Text | Extension of physical separation of ETC dedicated lanes and cash lanes should be accomplished using double 8 inch wide pavement markings. |
| Commentary | Except for standard edge markings, use of pavement markings within the queue and recovery zones should be evaluated based on such factors as traffic patterns, weather conditions, delays caused by maintenance, and improvements to operational performance. |
| Guideline | Pavement Marking/Channelization/Impact Attenuator Guideline 3 |
| Title | Dedicated Lane Channelization |
| Text | Dedicated lanes within a conventional plaza should use both barrier and pavement markings that extend upstream to approximately the point where approaching vehicle speed to the cash lanes drops below 30 mph during off peak hours. |
| Commentary | The 30 mph threshold is deemed to be a reasonable maximum speed through an ETC dedicated lane. Channelization is intended to prevent or discourage vehicles from attempting to enter a dedicated lane by unsafely crossing the cash lanes when the driver inadvertently failed to get into the proper lane when approaching the plaza. |
| Guideline | Pavement Marking/Channelization/Impact Attenuator Guideline 4 |
| Title | Toll Island/Impact Attenuator |
| Text | Impact attenuators/crash cushions should be installed at the approach end of all mainline plaza toll islands whenever the approach speed of vehicles can exceed 25 mph. |
| Commentary | For agencies to assure approach speeds do not exceed 25 mph, continuous rigorous enforcement using both enforcement personnel and speed detection devices in conjunction with a license plate capture system to issue high fines should be deployed. Exhibit 3-8 shows the condition of a 1999 Volkswagen Passsat after a front end collision with a stationary object when traveling at 35 miles per hour. The damage shown should not be considered indicative of the damage sustained by other types of vehicles, which may be considerably more severe and therefore supports use of a lower threshold speed for deploying an attenuator. |
| Guideline | Pavement Marking/Channelization/Impact Attenuator Guideline 5 |
| Title | Toll Island/Impact Attenuator |
| Text | Impact Attenuator/crash cushions for cash lanes should be designed for selected percent above the posted approach zone speed limit, plus 5 mph. For existing plazas, this percentage should be determined from field studies. Each impact attenuator/crash cushion type has specific requirements relative to cross slopes, grades, curbs, etc. Consequently, profile grades and cross slopes for new construction should be designed per the specification of the impact attenuator/crash cushion. |
| Commentary | Pavement markings offering warning to approaching motorists should be considered for placement immediately in front of the impact attenuator/crash cushions, in the form of a gore taper with diagonal striping or tapered chevrons. |
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