IEC 60529

"The standard applies to the classification of degrees of protection provided by enclosures for electrical equipment with a rated voltage not exceeding 72,5 kV. The object of the standard is to give a) Definitions for degrees of protection provided by enclosures of electrical equipment as regards: 1) protection of persons against access to hazardous parts inside the enclosure; 2) protection of the equipment inside the enclosure against ingress of solid foreign objects; 3) protection of the equipment inside the enclosure against harmful effects due to the ingress of water.