In many industrial applications, an IP40 industrial switch is already sufficient. IP40 protection effectively prevents solid objects larger than 1 mm from entering the enclosure, including coarse dust, metal fragments, and insects commonly found in industrial environments. IP rating stands for Ingress Protection Rating, an international standard defined by IEC 60529. So, when we are purchasing industrial switches, what is the. The protection level (IP level) of industrial switches is an important indicator used to measure their dust-proof, waterproof and other protective capabilities. The code follows the scheme: 1.