Principles of installation of traffic lights and signs
Mr. Trinh Van Binh, residing in Hung Nguyen district, asked: What are the principles for installing traffic lights, road signs and arranging road markings?
Reply
In Article 23,Road Law 2024 stipulates on lroad sign installationas follows:
- Principles of traffic light installation:
a) The light face must face the opposite direction of travel and must be placed in a position that is easily visible to road users;
b) The order of installation of traffic lights is vertical: red light on top, yellow light in the middle and green light on the bottom;
c) Order of installation of traffic lights horizontally: red light on the left side, yellow light in the middle and green light on the right side according to the direction of travel;

d) After installation, the traffic light system must be tested by the investor and road management agency in accordance with the requirements of road traffic organization before acceptance and putting into operation.
- Principles of road sign installation:
a) The sea surface faces the opposite direction of travel;
b) Placed on the right side or above the roadway. In some specific cases, additional signs may be placed on the left side in the direction of travel to guide and signal road users;
c) Placed in a position where road users can easily observe and perform;
d) Supplementary signs are used in combination to supplement and explain prohibition signs, danger signs, command signs and directional signs.
-On the principles of road marking arrangement:
a) Road markings are a form of road signaling painted on the road surface and on road structures;
b) Road markings can be arranged independently and can be combined with road signs or traffic lights.