The IP Code (or International Protection Rating, sometimes also interpreted as Ingress Protection Rating)* consists of the letters IP followed by two digits and an optional letter. As defined in international standard IEC 60529, it classifies the degrees of protection provided against the intrusion of solid objects (including body parts like hands and fingers), dust, accidental contact, and water in electrical enclosures. The standard aims to provide users more detailed information than vague marketing terms such as waterproof.

The digits (characteristic numerals) indicate conformity with the conditions summarized in the tables below. For example, an electrical socket rated IP22 is protected against insertion of fingers and will not be damaged or become unsafe during a specified test in which it is exposed to vertically or nearly vertically dripping water. IP22 or 2X are typical minimum requirements for the design of electrical accessories for indoor use.

*Explanation of the letters IP is given in IEC 60529 (Ed. 2.1), clause 4.1

First Digit: Solids

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.

Level Object Size Protected Against Effective Against
0 - No protection against contact and ingress of objects
1 >50 mm Any large surface of the body, such as the back of the hand, but no protection against deliberate contact with a body part
2 >12.5 mm Fingers or similar objects
3 >2.5 mm Tools, thick wires, etc.
4 >1 mm Most wires, screws, etc.
5 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; complete protection against contact
6 Dust Tight No ingress of dust; complete protection against contact

Second Digit: Solids

Protection of the equipment inside the enclosure against harmful ingress of water.

Level Protected Against Effective Against
0 Not protected -
1 Dripping water Dripping water (vertically falling drops) shall have no harmful effect.
2 Dripping water when tilted up to 15° Vertically dripping water shall have no harmful effect when the enclosure is tilted at an angle up to 15° from its normal position.
3 Spraying water Water falling as a spray at any angle up to 60° from the vertical shall have no harmful effect.
4 Splashing water Water splashing against the enclosure from any direction shall have no harmful effect.
5 Water jets Water projected by a nozzle (6.3 mm) against enclosure from any direction shall have no harmful effects.
6 Powerful water jets Water projected in powerful jets (12.5 mm nozzle) against the enclosure from any direction shall have no harmful effects.
7 Immersion up to 1 m 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).
8 Immersion beyond 1m The equipment is suitable for continuous immersion in water under conditions which shall be specified by the manufacturer. Normally, this will mean that the equipment is hermetically sealed. 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.
9k High pressure water/steam cleaning Water that is sprayed against the housing from every direction at a very high pressure must not cause damage (only applies to DIN 40050 PORT 9 testing)

IP Rating: Reference Chart

Level First Digit - Solids Second Digit - Liquid
IP00 Not protected from solids Not protected from liquids
IP01 Not protected from solids Protected from condensation
IP02 Not protected from solids Protected from water spray less than 15° from vertical
IP03 Not protected from solids Protected from water spray less than 60° from vertical
IP04 Not protected from solids Protected from water spray from any direction
IP05 Not protected from solids Protected from low pressure water jets from any direction
IP06 Not protected from solids Protected from high pressure water jets from any direction
IP07 Not protected from solids Protected from immersion between 15 cm and 1 m in depth
IP08 Not protected from solids Protected from long term immersion up to a specified pressure
IP10 Protected from touch by hands greater than 50 mm Not protected from liquids
IP11 Protected from touch by hands greater than 50 mm Protected from condensation
IP12 Protected from touch by hands greater than 50 mm Protected from water spray less than 15° from vertical
IP13 Protected from touch by hands greater than 50 mm Protected from water spray less than 60° from vertical
IP14 Protected from touch by hands greater than 50 mm Protected from water spray from any direction
IP15 Protected from touch by hands greater than 50 mm Protected from low pressure water jets from any direction
IP16 Protected from touch by hands greater than 50 mm Protected from high pressure water jets from any direction
IP17 Protected from touch by hands greater than 50 mm Protected from immersion between 15 cm and 1 m in depth
IP18 Protected from touch by hands greater than 50 mm Protected from long term immersion up to a specified pressure
IP20 Protected from touch by objects greater than 12 mm Not protected from liquids
IP21 Protected from touch by fingers greater than 12 mm Protected from condensation
IP22 Protected from touch by objects greater than 12 mm Protected from water spray less than 15° from vertical
IP23 Protected from touch by objects greater than 12 mm Protected from water spray less than 60° from vertical
IP24 Protected from touch by objects greater than 12 mm Protected from water spray from any direction
IP25 Protected from touch by objects greater than 12 mm Protected from low pressure water jets from any direction
IP26 Protected from touch by objects greater than 12 mm Protected from high pressure water jets from any direction
IP27 Protected from touch by objects greater than 12 mm Protected from immersion between 15 cm and 1 m in depth
IP28 Protected from touch by objects greater than 12 mm Protected from long term immersion up to a specified pressure
IP30 Protected from tools and wires greater than 2.5 mm Not protected from liquids
IP31 Protected from tools and wires greater than 2.5 mm Protected from condensation
IP32 Protected from tools and wires greater than 2.5 mm Protected from water spray less than 15° from vertical
IP33 Protected from tools and wires greater than 2.5 mm Protected from water spray less than 60° from vertical
IP34 Protected from tools and wires greater than 2.5 mm Protected from water spray from any direction
IP35 Protected from tools and wires greater than 2.5 mm Protected from low pressure water jets from any direction
IP36 Protected from tools and wires greater than 2.5 mm Protected from high pressure water jets from any direction
IP37 Protected from tools and wires greater than 2.5 mm Protected from immersion between 15 cm and 1 m in depth
IP38 Protected from toolswand wires greater than 2.5 mm Protected from long term immersion up to a specified pressure
PI40 Protected from tools and small wires greater than 1 mm Not protected from liquids
IP41 Protected from tools and small wires greater than 1 mm Protected from condensation
IP42 Protected from tools and small wires greater than 1 mm Protected from water spray less than 15° from vertical
IP43 Protected from tools and small wires greater than 1 mm Protected from water spray less than 60° from vertical
IP44 Protected from tools and small wires greater than 1 mm Protected from water spray from any direction
IP45 Protected from tools and small wires greater than 1 mm Protected from low pressure water jets from any direction
IP46 Protected from tools and small wires greater than 1 mm Protected from high pressure water jets from any direction
IP47 Protected from tools and small wires greater than 1 mm Protected from immersion between 15 cm and 1 m in depth
IP48 Protected from tools and small wires greater than 1 mm Protected from long term immersion up to a specified pressure
IP50 Protected from limited dust ingress Not protected from liquids
IP51 Protected from limited dust ingress Protected from condensation
IP52 Protected from limited dust ingress Protected from water spray less than 15° from vertical
IP53 Protected from limited dust ingress Protected from water spray less than 60° from vertical
IP54 Protected from limited dust ingress Protected from water spray from any direction
IP55 Protected from limited dust ingress Protected from low pressure water jets from any direction
IP56 Protected from limited dust ingress Protected from high pressure water jets from any direction
IP57 Protected from limited dust ingress Protected from immersion between 15 cm and 1 m in depth
IP58 Protected from limited dust ingress Protected from long term immersion up to a specified pressure
IP60 Protected from total dust ingress Not protected from liquids
IP61 Protected from total dust ingress Protected from condensation
IP62 Protected from total dust ingress Protected from water spray less than 15° from vertical
IP63 Protected from total dust ingress Protected from water spray less than 60° from vertical
IP64 Protected from total dust ingress Protected from water spray from any direction
IP65 Protected from total dust ingress Protected from low pressure water jets from any direction
IP66 Protected from total dust ingress Protected from high pressure water jets from any direction
IP67 Protected from total dust ingress Protected from immersion between 15 cm and 1 m in depth
IP68 Protected from total dust ingress Protected from long term immersion up to a specified pressure
IP69k Protected from total dust ingress Protected from steam jet cleaning

*References
1. IEC 60529, “Degrees of Protection Provided by Enclosures (IP Codes),” Ed. 2.1 (Geneva: International Electrotechnical Commission, 2001)
2. IEC 60529 (Ed 2.1), clause 4.1