CONVENTION ON ROAD SIGNS AND SIGNALS

The Contracting Parties, recognizing that international uniformity of road signs, signals and symbols and of road markings is necessary in order to facilitate international road traffic and to increase road safety, have agreed upon the following provisions:

Chapter III

TRAFFIC LIGHT SIGNALS

ARTICLE 23

Signals for vehicular traffic

1. Subject to the provisions of paragraph 12 of this Article, the only lights which may be used as light signals for regulating vehicle traffic, other than those intended solely for public transport vehicles, are the following, which shall have the meanings here assigned to them:

(a) Non-flashing lights:

(i) A green light shall mean that traffic may proceed; however, a green light for controlling traffic at an intersection shall not authorize drivers to proceed if traffic is so congested in the direction in which they are about to proceed that if they entered the intersection they would probably not have cleared it by the next change of phase;

(ii) A red light shall mean that traffic may not proceed; vehicles shall not pass the stop line or, if there is no stop line, shall not pass beyond the level of the signal or, if the signal is placed in the middle or on the opposite side of an intersection, shall not enter the intersection or move on to a pedestrian crossing at the intersection;

(iii) An amber light, which shall appear alone or at the same time as the red light; when appearing alone it shall mean that no vehicle may pass the stop line or beyond the level of the signal unless it is so close to the stop line or signal when the light appears that it cannot safely be stopped before passing the stop line or beyond the level of the signal. Where the signal is placed in the middle or on the opposite side of an intersection the appearance of the amber light shall mean that no vehicle may enter the intersection or move on to a pedestrian crossing at the intersection unless it is so close to the crossing or the intersection when the light appears that it cannot be safely stopped before entering the intersection or moving on to the pedestrian crossing. When shown at the same time as the red light, it shall mean that the signal is about to change, but shall not affect the prohibition of passing indicated by the red light;

            (b) Flashing lights:

(i) A red flashing light, or two red lights flashing alternately, one light appearing when the other is extinguished, and mounted on the same support, at the same height, and facing the same direction shall mean that vehicles shall not pass the stop line or, if there is no stop line, shall not pass beyond the level of the signal; these lights may be used only at level-crossings, at approaches to swing bridges or ferry-boat landing stages, and to indicate that traffic may not proceed because of fire-fighting vehicles entering the road or of the approach of an aircraft which will cross the road at a lower altitude;

(ii) A single amber flashing light or two amber lights flashing alternately shall mean that drivers may proceed but shall do so with particular care.

2. The signals of the three-colour system shall consist of three non-flashing lights, which shall be red, amber and green respectively; the green light shall appear only when the red and amber lights are extinguished.

3. The signals of the two-colour system shall consist of a non-flashing red light and a non-flashing green light. The red light and the green light shall not appear at the same time. Signals of the two-colour system shall be used only in temporary installation, subject to the period allowed under Article 3, paragraph 3, of this Convention for the replacement of existing installations.

3-bis. (a) The provisions of Article 6, paragraphs 1, 2 and 3, of the Convention which relate to road signs shall apply to traffic light signals other than those used at level-crossings.

(b) Traffic light signals at intersections shall be placed before the intersection or in the middle of and above it; they may be repeated at the far side of the intersection and/or at the driver’s eye level.

(c) In addition, it is recommended that domestic legislation should provide that traffic light signals:

(i) Shall be so placed as not to impede vehicles moving in traffic on the carriageway and, in the case of signals set up on verges, as to impede pedestrians as little as possible;

(ii) Shall be easily visible from a distance and readily understandable as they are approached; and

(iii) Shall be standardized in the territory of each Contracting Party for the various categories of roads.

4. The lights of the three-colour and two-colour systems referred to in paragraphs 2 and 3 of this Article shall be arranged vertically or horizontally.

5. Where the lights are arranged vertically, the red light shall be placed uppermost; where the lights are arranged horizontally, the red light shall be placed on the side opposite to that appropriate to the direction of traffic.

6. In the three-colour system, the amber light shall be placed in the middle.

7. All the lights in the signals of the three-colour and two-colour systems referred to in paragraphs 2 and 3 of this Article shall be circular. The red flashing lights referred to in paragraph 1 of this Article shall likewise be circular.

8. A flashing amber light may be installed alone; such a light may also be used in place of a three-colour system at times when traffic is light.

9. In a three-colour system, the red, amber and green lights may be replaced by arrows of the same colour on a black background. When lighted up, these arrows have the same significance as the lights, but the prohibition or authorization is restricted to the direction or directions indicated by the arrow or arrows. Arrows signifying that traffic may or may not proceed straight ahead shall point upwards. Black arrows on a red, amber or green background may be used. These arrows have the same significance as the above-mentioned arrows.

10. Where a signal of a three-colour system includes one or more additional green lights showing one or more arrows, the lighting of such additional arrow or arrows shall, no matter what phase the three-colour system may be in at the time, mean that traffic may proceed in the direction or directions indicated by the arrow or arrows; it shall also mean that, when vehicles are in a lane reserved for traffic in the direction indicated by the arrow or the direction such traffic is required to take, their drivers must proceed in the direction indicated if by stopping they would obstruct the movement of vehicles behind them in the same lane, provided always that vehicles in the traffic stream they are joining must be allowed to pass and that pedestrians must not be endangered. These additional green lights should preferably be placed at the same level as the normal green light.

11. (a) Where green or red lights are placed above traffic lanes shown by longitudinal markings on a carriageway having more than two lanes, the red light shall mean that traffic may not proceed along the lane over which it is placed and the green light shall mean that traffic may so proceed. The red light thus placed shall be in the form of two inclined crossed bars and the green light in the form of an arrow pointing downwards.

(b) When the competent authorities judge it necessary to introduce an "intermediate" or "transition" signal for the light signals, it should be in the form of an amber or white arrow pointing diagonally downwards to the left or to the right, or two such arrows, one pointing in each direction; these arrows may be flashing. These amber or white arrows mean that the lane is about to be closed to traffic and that the road-users on that lane must move over to the lane indicated by the arrow.

12. Domestic legislation may provide for the installation at certain level-crossings of a slow-flashing lunar white light meaning that traffic may proceed.

13. In cases where traffic light signals apply to cyclists only, this restriction may be clarified, if to do so is necessary in order to avoid confusion, by including the silhouette of a cycle in the signal itself or by using a signal of small size supplemented by a rectangular plate showing a cycle.