The IP Code, or ingress protection rating, European standard EN 60529. It classifies and rates the degree of protection provided against intrusion by dust and water by mechanical casings and electrical enclosures.

The IP Code is written as IPxx - where the first x relates to the protection against dust and the second x relates to the protection against water.

Minimum Ratings for Applications:
IP44 (no objects >1mm and splash proof) is suitable for bathroom/kitchen (zones 1,2 and 3) installations. 
IP65 (dust tight and protection against water jets)  is suitable for outdoor use.


First Digit: Solid Particle Protection

The first digit indicates the level of protection that the enclosure provides against access to hazardous parts (e.g., electrical conductors, moving parts) and the ingress of solid foreign objects.

Number
Effective Against
Notes
IP0x

N/A

No protection against contact and ingress of objects

IP1x

>50mm

Protected against ingress of any large surface of the body, such as the back of a hand, but no protection against deliberate contact with a body part

IP2x

>12.5mm

Protected against ingress of fingers or similar objects

IP3x

>2.5mm

Protected against ingress of tools, thick wires, etc.

IP4x

>1mm

Protected against ingress of most wires, slender screws, large ants etc.

IP5x

Dust Protected

Ingress of dust is not entirely prevented, but it must not enter in sufficient quantity to interfere with the satisfactory operation of the equipment.

IP6x

Dust Tight

There is no ingress of dust; complete protection against contact (dust tight). A vacuum must be applied. Test duration of up to 8 hours based on air flow.


Second Digit: Liquid Ingress Protection

The second digit indicates the level of protection that the enclosure provides against harmful ingress of water.

Number
Protection Against
Effective Against
IPx0

N/A

N/A

IPx1

Dripping water

Dripping water (vertically falling drops) shall have no harmful effect on the specimen when mounted in an upright position onto a turntable and rotated at 1RPM.

IPx2

Dripping water when tilted at 15°

Vertically dripping water shall have no harmful effect when the enclosure is tilted at an angle of 15° from its normal position. A total of four positions are tested within two axes.

IPx3

Spraying water

Water falling as a spray at any angle up to 60° from the vertical shall have no harmful effect, utilizing either: a) an oscillating fixture, or b) A spray nozzle with a counterbalanced shield.Test a) is conducted for 5 minutes, then repeated with the specimen tilted 90° for the second 5-minute test. Test b) is conducted (with shield in place) for 5 minutes minimum.

IPx4

Splashing of water

Water splashing against the enclosure from any direction shall have no harmful effect, utilizing either: a) an oscillating fixture, or b) A spray nozzle with no shield.Test a) is conducted for 10 minutes. Test b) is conducted (without shield) for 5 minutes minimum.

IPx5

Water jets

Water projected by a nozzle (6.3 mm) against enclosure from any direction shall have no harmful effects

IPx6

Powerful water jets

Water projected in powerful jets (12.5 mm nozzle) against the enclosure from any direction shall have no harmful effects.

IPx6K

Powerful water jets with increased pressure

Water projected in powerful jets (6.3 mm nozzle) against the enclosure from any direction, under elevated pressure, shall have no harmful effects.

IPx7

Immersion, up to 1m depth

Ingress of water in harmful quantity shall not be possible when the enclosure is immersed in water under defined conditions of pressure and time (up to 1 m of submersion).

IPx8

Immersion, 1m or more depth

The equipment is suitable for continuous immersion in water under conditions which shall be specified by the manufacturer. However, with certain types of equipment, it can mean that water can enter but only in such a manner that it produces no harmful effects. The test depth and/or duration is expected to be greater than the requirements for IPx7, and other environmental effects may be added, such as temperature cycling before immersion.

IPx9K

Powerful high temperature water jets

Protected against close-range high pressure, high temperature spray downs. Smaller specimens rotate slowly on a turntable, from 4 specific angles. Larger specimens are mounted upright, no turntable required, and are tested freehand for at least 3 minutes at distance of 0.15–0.2 m. There are specific requirements for the nozzle used for the testing.