For infectious diseases, isolation is required mainly to prevent the spread of pathogens to avoid causing disease epidemics, and furthermore to facilitate disease management, disinfection and treatment. According to the different ways of transmission of infectious diseases, can be divided into a variety of different isolation methods, different isolation methods can choose different color signs. First, seen in strict isolation, choose yellow signs, mainly for highly contagious class A or class B infectious diseases. Second, respiratory isolation using blue signs, gastrointestinal isolation choose brown signs, contact isolation choose orange signs, blood body fluid isolation choose red signs. Different color signs are helpful for the correct differentiation of the corresponding isolation measures in the clinic, which is conducive to the management, isolation and treatment of infectious diseases.