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 II
ROAD SIGNS
DANGER WARNING SIGNS
ARTICLE 9
1. Section A, subsection I of Annex 1 to this Convention indicates the models for danger warning signs; Section A, subsection II indicates the symbols to be placed on these signs and gives some instructions for their use. In conformity with Article 46, paragraph 2 of this Convention, each State shall notify the Secretary-General whether it has selected Aa or Ab as the model for danger warning signs.
2. The number of danger warning signs shall not be increased unnecessarily, but such signs shall be sited to give warning of possible road hazards which are difficult for a driver proceeding with due caution to perceive in time.
3. Danger warning signs shall be placed at such distance from the danger point as will make them most effective both by day and by night, having regard to road and traffic conditions, including the normal speed of vehicles and the distance at which the sign is visible.
4. The distance between the sign and the beginning of a dangerous section of road may be shown in an additional panel H, 1 of Annex 1, section H to this Convention and placed in accordance with the provisions of that section; this information must be given when the distance between the sign and the beginning of the dangerous section of road cannot be judged by drivers and is not what they might normally expect.
5. Danger warning signs may be repeated, particularly on motorways and roads treated as motorways. Where they are repeated, the distance between the sign and the beginning of the dangerous section of road shall be shown in accordance with the provisions of paragraph 4 of this Article. However, with respect to danger warning signs giving warning of swing bridges and level crossings, it shall be open to Contracting Parties to apply the following provisions:
A rectangular panel having its longer sides vertical and bearing three oblique red bars on a white or yellow ground may be placed below any danger warning sign bearing one of the symbols A, 5; A, 25; A, 26 or A, 27 described in Annex 1, section A, subsection II, paragraphs 5, 25, 26 and 27 to this Convention, provided that additional signs consisting of panels of the same shape bearing respectively one or two oblique red bars on a white or yellow ground are set up at about one third and two thirds of the distance between the sign and the railway line. These signs may be repeated on the opposite side of the carriageway. The panels mentioned in this paragraph are further depicted in section A, subsection II, paragraph 29 of Annex 1 to this Convention.
6. If a danger warning sign is used to give warning of a danger on a section of road of some length (e.g. a series of dangerous bends or a section of carriageway in bad condition) and if it is considered desirable to show the length of that section, this shall be done on an additional panel H, 2 of Annex 1, section H to this Convention, placed in accordance with the provisions of that section.