This recommendation covers graphical symbols which are:
a) placed on equipment or parts of equipment of any kind in order to instruct the persons handling the equipment as to its use and operation;
b) placed on sites and ways where people may assemble or move, giving them instructions, such as prohibitions, warnings, rules or limits, for their behaviour;
c) also used in pictorial reproductions, such as plans, drawings, maps, diagrams and similar documents.