Sign 2 is a compulsory stop sign. Effective for forcing motorized and rudimentary vehicles, including priority vehicles, to stop in front of the sea or in front of the road crossing and are only allowed to go when seeing the signals (by people). traffic control or lights, flag) allow to go.
Stop at the signal of the traffic controller when a train is about to pass.
Stopping when there is a vehicle going in the opposite direction on a narrow bridge, when on the road there is a risk of traffic safety.