Designing an Emergency Traffic Signal System (ETSS): A Case Study of an Intersection Along U.S.1, Fairfax County, Virginia

Access to highways from a local firehouse is a major problem for emergency services. Motorists often do not see flashing lights or hear sirens from the approaching emergency vehicles (EV) until emergency vehicles reach the highway entrance, often too late to take appropriate action. Many locations have installed special signals called emergency traffic signal systems (ETSS) or used signal preemption to notify motorists and to stop traffic to allow the emergency vehicle to enter the highway safely. This thesis will examine the effectiveness of one such installation at the intersection along U.S.1 at Beedo Street and some of the impacts it has on highway traffic. The evaluation of the said installation is carried out in terms of delay to EV; conflict potential between EV and other vehicles and response of the motorists to the ETSS. This thesis also proposes two alternative designs of ETSS to improve the existing signal system.