• The enclosure class is designated according to DIN 40050, by IP and a two-figure code number.
    1st digit Degree of protection against ingress of solid bodies:
    0 no special protection
    1 solid bodies with dia. > 50 mm, no protection against intentional penetration
    2 solid bodies with dia. > 12 mm, warding off fingers etc.
    3 solid bodies with dia. > 2.5 mm, warding off tools, wires, etc. (thickness > 2.5 mm)
    4 solid bodies with dia. > 1 mm, warding off tools, wires, etc. (thickness > 1 mm)
    5 dust in harmful quantities, complete shock-hazard protection
    6 dust (dust-tight), complete shock-hazard protection
  • 2nd digit Degree of protection against water
    0 no special protection
    1 water dripping vertically
    2 water dripping at angles up to 15° from vertical
    3 water dripping at angles up to 60° from vertical (spraying water)
    4 water from all directions (splashing water)
    5 water from a nozzle from all directions (hose-water)
    6 heavy seas or strong jet of water (flooding)
    7 water, if the device is immersed in water under specified conditions of pressure and time (immersion)
    8 water, if the device is submerged constantly. The manufacturer must describe the conditions (submersion)

(For numbers 1 to 8, water must not penetrate in harmful quantities.)
Example: IP 65 A device thus designated is dust-tight, and protected against hose-water.