General safety colors used are the following

1 , Red: used to mark the ban , stop and fire , such as lights, signal flags , emergency stop buttons on the machine are to indicate "No " message in red.
2, yellow :  photoluminescent pigment  danger signs . Such as " Beware of electric shock" , " pay attention to security" .
3 , green : to mark the safe thing. Such as " In this job ," " grounded " and so on.
4 , Blue: used to mark the enforcement , such as " must wear helmets " and so on .
5 , Black: used to mark images, text and warning signs in line geometry .
According to regulations, for ease of identification, to prevent misuse and ensure safe operation and maintenance decorative aggregate, using different colors to distinguish the device characteristics . The electrical bus , A yellow phase , B phase is green , C phase is red, for surface coating of black ground . In the second system, the AC voltage circuit with yellow , green alternating current circuits , signals and warning circuits with white .