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Mandatory Street Signs
These are the street signs that are used-to set the obligations-of all traffic that use a specific road area. Unlike the restrictive or prohibitory signs, these signs will tell the traffic what it should do, instead of what it shouldn't do. Most mandatory signs are circular, and they may use white-symbols on a blue-background with a white border or some black symbol-on the white background with red border, though the latter can also be associated with restrictive/prohibitory signs.
All street signs which utilize a circular red-ring are mandatory signs, or street signs that give orders. A motorist must abide-by the instructions that are given in the regulatory signs so as to remain within law. The signs are used-to inform road users/drivers of certain laws & regulations so as to provide safety & free flow of the traffic. These includes all signs that give notice-of special obligation, restrictions or prohibitions with which a road user should comply. Violation of the signs is a legal-offence. These signs are basically obligatory on exactly which traffic uses the specified area of road. The signs indicate what needs ti be done. Mandatory signs are usually round-in-shape with a red border. Some are blue-in-colour. 'Stop' & 'Give Way' are octagon & triangular, respectively. Violation of the signs attracts fines & punishments, it could also lead to major car accidents.
Mandatory signs are a sub-set of the regulatory sign-group as defined by United Nations Economic & Social Council in Vienna Convention on Street Signs & Signals of the year 1968, and they're usually seen not just-on their own, but normally used in conjunction with some other signs, bollards and traffic lights as a form-of visual shorthand within the objects. In the Vienna Convention signatories, a mandatory street sign is either light blue circle which has a white border (that is, Type A) or white circle that has a red border (that is, Type B). The signs should be at least 60-cm (that is, 1.96 feet) across on the rural roads, or 40-cm (that is, 1.31 feet) in built up areas, though mandatory street signs incorporated in the traffic lights, bollards or other larger street signs may be as-little-as 30 cm (that is, 0.98 feet) in diameter.
Mandatory road signs may be used in allocating certain areas to certain specific vehicles (Vienna Convention explicitly-mentions bridleways, footpaths and cyclepaths, but snow mobile tracks, tramways, bus lanes, HOV lanes and taxi lanes may also be designated using these signs.) When a certain specific area of the road is designated using a mandatory sign specifying certain vehicle types, all the traffic of the mentioned type should use that area whenever possible. The signs may be combined-by putting 1 pictogram over another. If these pictograms are side by side however, with the signs divided-by a white vertical-line, each type-of vehicle/car should stay within lane(s) indicated by that sign. A red-line through the sign indicates not-that a vehicle/car of a certain specific type is prohibited-from entering that designated area, but that, this area is now de-regulated & any vehicle/car can use it.
These mandatory signs may also be used-to issue instructions to vehicles, some common examples can include "pass on this-side" signs which are usually seen at road works, and "compulsory-roundabout" signs which are seen at mini roundabouts. Some other signs of this type include "attach snow-chains" and "remove snow-chains" which are seen at entry and exit points-of mountainous areas, & "compulsory direction-for vehicles/cars carrying dangerous or heavy loads", which are used to divert the vehicles carrying poisonous chemicals or explosives away from all areas which have open flames like oil refineries.
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