According to the Manual of Uniform Traffic Control Devices, a minimum of two through signal faces is always required, said Denys Vielkanowitz, signal systems management engineer for the city of Wilmington.
Additionally, each protected only turn lane (left and right) requires its own signal head, Vielkanowitz said.
In summary:
- Protected Only Left Lane – one signal head
- Protected Only Left Lane – one signal head
- Through Lane – two signal heads
- Protected Only Right Lane – one signal head
- Protected Only Right Lane – one signal head
Date posted: April 6, 2011
User-contributed question by:
Eleanor M. Greentree
