Mandatory Signs That Warn About Weather Conditions
Mandatory signs that warn about weather conditions specify what must be done and what instructions must be carried out. Mandatory signs usually use symbols (or "picto-grams") which are depicted in white on a blue-circular background with white borders. They can also use sign wording when necessary, which should be in black-lettering on a white-background with red borders. Mandatory signs are normally used to set obligations mostly on traffic using a specific road or area which has been damaged by bad weather conditions. Unlike restrictive or prohibitory-signs, mandatory signs always tell the traffic what must be done, rather than what must not be done. Most mandatory signs that warn about weather conditions are circular. They normally use white-symbols on a blue-background with white borders or black-symbols on a white-background with red borders, although the-latter is usually associated with the prohibitory signs.
Mandatory signs are sometimes used to allocate specific areas to certain vehicles, for example, the Vienna-Convention mentions, cycle paths, foot paths and bridle ways, but bus lanes, tramways, taxi lanes, snow mobile tracks and HOV lanes can at times be designated with mandatory-signs. When a certain area of road-way is designated with a mandatory sign which specifies a certain vehicle type, all of the traffic specified by the sign must use this designated area whenever possible. Mandatory signs can also be combined by putting 1 pictogram over or above the other. If the picto-grams happen to be side by side however, and the sign is divided by a white-vertical line, each specified type of vehicle should and must stay within the exact lane indicated by that sign. A red-line running through a mandatory sign typically indicates that the specified or shown vehicle is not prohibited from driving or entering the indicated designated area, but that the designated area is now de-regulated and any and all vehicles can use it.
Mandatory signs that warn about weather conditions can be termed as a sub-set of the regulatory-sign group as clearly defined by the United-Nations Economic and Social-Council in the Vienna-Convention on Road-Signs and Signals of the year 1968. Mandatory signs are not often seen on their own, but are normally used in conjunction or along with other road and safety signs, traffic-lights and even bollards, usually as a form-of visual-shorthand within the objects. In Vienna-signatories, a mandatory sign should either be light blue and circular with a white-border or a white and circular with a red-border. A mandatory sign should be at least 60-cm (that is, 1.96 feet) across on rural-roads, or 40-cm (that is, 1.31 feet) in built up areas. However, most mandatory signs that incorporate traffic lights or bollards or other larger road-signs can be as small as 30-cm (that is, 0.98 feet) in diameter.
Mandatory signs can also be used to give instructions to all cars and vehicles, for example, they can give instructions like: "Pass-on this side" signs which can be seen at roadworks during floods, and "Compulsory-roundabout" signs which can be seen at mini roundabouts. Other such mandatory signs can include; "Attach snow-chains" and "Remove snow-chains" signs which can be seen at the exit or entry points of mountainous weather affected areas, and "Compulsory-direction for cars/vehicles carrying heavy or dangerous loads" signs used to divert cars/vehicles carrying heavy, explosive or poisonous loads away from weather affected areas.
Mandatory signs are sometimes used to allocate specific areas to certain vehicles, for example, the Vienna-Convention mentions, cycle paths, foot paths and bridle ways, but bus lanes, tramways, taxi lanes, snow mobile tracks and HOV lanes can at times be designated with mandatory-signs. When a certain area of road-way is designated with a mandatory sign which specifies a certain vehicle type, all of the traffic specified by the sign must use this designated area whenever possible. Mandatory signs can also be combined by putting 1 pictogram over or above the other. If the picto-grams happen to be side by side however, and the sign is divided by a white-vertical line, each specified type of vehicle should and must stay within the exact lane indicated by that sign. A red-line running through a mandatory sign typically indicates that the specified or shown vehicle is not prohibited from driving or entering the indicated designated area, but that the designated area is now de-regulated and any and all vehicles can use it.
Mandatory signs that warn about weather conditions can be termed as a sub-set of the regulatory-sign group as clearly defined by the United-Nations Economic and Social-Council in the Vienna-Convention on Road-Signs and Signals of the year 1968. Mandatory signs are not often seen on their own, but are normally used in conjunction or along with other road and safety signs, traffic-lights and even bollards, usually as a form-of visual-shorthand within the objects. In Vienna-signatories, a mandatory sign should either be light blue and circular with a white-border or a white and circular with a red-border. A mandatory sign should be at least 60-cm (that is, 1.96 feet) across on rural-roads, or 40-cm (that is, 1.31 feet) in built up areas. However, most mandatory signs that incorporate traffic lights or bollards or other larger road-signs can be as small as 30-cm (that is, 0.98 feet) in diameter.
Mandatory signs can also be used to give instructions to all cars and vehicles, for example, they can give instructions like: "Pass-on this side" signs which can be seen at roadworks during floods, and "Compulsory-roundabout" signs which can be seen at mini roundabouts. Other such mandatory signs can include; "Attach snow-chains" and "Remove snow-chains" signs which can be seen at the exit or entry points of mountainous weather affected areas, and "Compulsory-direction for cars/vehicles carrying heavy or dangerous loads" signs used to divert cars/vehicles carrying heavy, explosive or poisonous loads away from weather affected areas.
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