Green times can be determined by several means. The basic principle for all methods is that green times should be proportional to the amount of traffic demand and the number of lanes on each approach. Green times should be re-evaluated periodically, especially when changes to traffic patterns occur, and signal timings adjusted to provide optimum timing efficiency.
Methods to calculate green times include:
- Highway Capacity Software by the Transportation Research Board (TRB)
- SYNCHRO Synchro Software by Trafficware
- TRANSYT-7F program by McTrans Center, University of Florida