Journal of Korean Society of Transportation ISSN:1229-1366(Print) 2234-4217(Online) 대한교통학회지

Recently, there is a trend of expanding the introduction of preemption/priority signals for emergency vehicles to secure golden time in disaster situations such as fire, rescue, and first aid. A preemption/priority signal strategy to minimize the response time of emergency vehicles is required because response time is directly connected to safety and life, but in Korea, there is a limitation in application due to lack of signal operation strategy and detailed operational criteria. Besides, the transit strategy for returning to the ordinary signal is indefinite, which may adversely affect other traffic flows after passing an emergency vehicle. For this reason, this study proposes preemption/priority signal operation criteria for securing emergency vehicle golden time and minimizing congestion, suggest the appropriate preemption/priority signal operation standard and return strategy acrroding to traffic volume. Network and signal scenarios were designed and analyzed using VISSIM and VAP, a microscopic traffic simulation program. As a result of the analysis, according to the degree of saturation in the intersection, it was found that the Preemption is advantageous when a v/c ratio above 0.4 to 0.6 and that Priority is advantageous when the v/c ratio exceeds 0.8. In the case of the transit signal, it was found that it is desirable to apply the Dwell if the difference in traffic volume between the main/minor road is 3:1 or more, and the Smooth if it is less than that. The introduction of the proposed preemption/priority signal in Korea is expected to affect the efficient response system of emergency vehicles and increase the on-site response capacity.