Utah Code § 41-6a-308: Lane use control signals -- Colors.

(1) The operator of a vehicle facing a traffic-control signal placed to control individual lane use shall obey the signal as follows:

(a) Green signal -- vehicular traffic may travel in any lane over which a green signal is shown.

(b) Steady yellow signal -- vehicular traffic is warned that a lane control change is being made.

(c) Steady red signal -- vehicular traffic may not enter or travel in any lane over which a red signal is shown.

(d) Flashing yellow signal -- vehicular traffic may use the lane only for the purpose of approaching and making a left turn.

(2) A violation of this section is an infraction.