The IP Code, Ingress Protection Rating,  sometimes also interpreted as International Protection Rating, classifies and rates the degree of protection provided against the intrusion of solid objects (including body parts like hands and fingers), dust, accidental contact, and water in mechanical casings and with electrical enclosures.
The standard aims to provide users more detailed information than vague marketing terms such as waterproof. However, no edition of the standard is openly published for unlicensed readers.
The digits (characteristic numerals) indicate conformity with the conditions summarized in the tables below. Where there is no protection rating with regard to one of the criteria, the digit is replaced with the letter X.
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.
Code breakdown 
|IP indication||Solid particle protection||Liquid ingress protection||Mechanical impact resistance||Other protections|
|IP||Single numeral: 0-6||Single numeral: 0-8||Single numeral: 0-9||Single letter|
|Mandatory||Mandatory||Mandatory||No longer used||Optional|
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.
|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 a 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|
Liquid ingress protection 
The second digit indicates the level of protection that the enclosure provides against harmful ingress of water.
|Level||Protected against||Testing for||Details|
|1||Dripping water||Dripping water (vertically falling drops) shall have no harmful effect.||Test duration: 10 minutes
Water equivalent to 1 mm rainfall per minute
|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.||Test duration: 10 minutes
Water equivalent to 3 mm rainfall per minute
|3||Spraying water||Water falling as a spray at any angle up to 60° from the vertical shall have no harmful effect.||Test duration: 5 minutes
Water volume: 0.7 litres per minute
|4||Splashing of water||Water splashing against the enclosure from any direction shall have no harmful effect.||Test duration: 5 minutes
Water volume: 10 litres per minute
|5||Water jets||Water projected by a nozzle (6.3 mm) against enclosure from any direction shall have no harmful effects.||Test duration: at least 3 minutes
Water volume: 12.5 litres per minute
|6||Powerful water jets||Water projected in powerful jets (12.5 mm nozzle) against the enclosure from any direction shall have no harmful effects.||Test duration: at least 3 minutes
Water volume: 100 litres per minute
|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).||Test duration: 30 minutes
Immersion at depth of at least 1 m measured at bottom of device, and at least 15 cm measured at top of device
|8||Immersion beyond 1 m||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.||Test duration: continuous immersion in water
Depth specified by manufacturer
Additional letters 
The standard defines additional letters that can be appended to classify only the level of protection against access to hazardous parts by persons:
|Level||Protected against access to hazardous parts with|
|A||Back of hand|
Further letters can be appended to provide additional information related to the protection of the device:
|H||High voltage device|
|M||Device moving during water test|
|S||Device standing still during water test|
Mechanical impact resistance 
An additional number has sometimes been used to specify the resistance of equipment to mechanical impact. This mechanical impact is identified by the energy needed to qualify a specified resistance level, which is measured in joules (J). This has now been superseded by the separate IK number specified in EN 62262.
Although dropped from the 3rd edition of IEC 60529 onwards, and not present in the EN version, older enclosure specifications will sometimes be seen with an optional third IP digit denoting impact resistance. Newer products are likely to be given an IK rating instead. However there is not an exact correspondence of values between the old and new standards.
|Dropped IP level||Impact energy||Equivalent drop mass and height|
|1||0.225 J||150 g dropped from 15 cm|
|2||0.375 J||250 g dropped from 15 cm|
|3||0.5 J||250 g dropped from 20 cm|
|5||2 J||500 g dropped from 40 cm|
|7||6 J||1.5 kg dropped from 40 cm|
|9||20 J||5.0 kg dropped from 40 cm|
|01||0.15||Drop of 200 g object from 7.5 cm height|
|02||0.2||Drop of 200 g object from 10 cm height|
|03||0.35||Drop of 200 g object from 17.5 cm height|
|04||0.5||Drop of 200 g object from 25 cm height|
|05||0.7||Drop of 200 g object from 35 cm height|
|06||1||Drop of 500 g object from 20 cm height|
|07||2||Drop of 500 g object from 40 cm height|
|08||5||Drop of 1.7 kg object from 29.5 cm height|
|09||10||Drop of 5 kg object from 20 cm height|
|10||20||Drop of 5 kg object from 40 cm height|
IPX Coding 
The letter X is used in any place in the code where specifying a digit is meant to be avoided (or indicates irrelevance based on the common application). There may be various reasons for choosing this coding variant, such as marketing considerations. Thus, e.g. an IPX7 rating for a consumer device specifies that the device has water protection up to limited immersion, but gives deliberately no information as to whether the device has any protection against mechanical ingress or dust. In the case of an IPX7 rating, however, a considerable level of protection against the ingress of solids can be assumed, as where a liquid ingress protection rating equals 7, the rating of protection against solids is rarely below 6, e.g. IP67. Among other common IP ratings using the letter X are IPX4. IP2X is frequently used on electrical items to specify the item must prevent finger access to live terminals i.e plug sockets are IP2X.
German standard DIN 40050-9 extends the IEC 60529 rating system described above with an IP69K rating for high-pressure, high-temperature wash-down applications. Such enclosures must not only be dust tight (IP6X), but also able to withstand high-pressure and steam cleaning.
The test specifies a spray nozzle that is fed with 80°C water at 8–10 MPa (80–100 bar) and a flow rate of 14–16 L/min. The nozzle is held 10–15 cm from the tested device at angles of 0°, 30°, 60° and 90° for 30s each. The test device sits on a turntable that rotates once every 12s (5rpm).
The IP69K test specification was initially developed for road vehicles, especially those that need regular intensive cleaning (dump trucks, cement mixers, etc.), but also finds use in other areas (e.g., food industry, car wash centres).
NEMA rating 
|IP Code||Min. NEMA Enclosure rating to satisfy IP Code|
The United States National Electrical Manufacturers Association (NEMA) also publishes protection ratings for enclosures similar to the IP rating system published by the International Electrotechnical Commission (IEC). However, it also dictates other product features not addressed by IP codes, such as corrosion resistance, gasket aging, and construction practices. Thus, while it is possible to map NEMA enclosure rating|NEMA ratings that satisfy or exceed the IP Code criteria, it is not possible to map IEC ratings (IP codes) to NEMA enclosure ratings, as the IP Code does not mandate the additional requirements. The table above indicates the minimum NEMA rating that satisfies or exceeds a given IP code, but can only be used in that way, not to map IP to NEMA.
See also 
- EN 62262 – IK code on resistance to mechanical impacts
- National Electrical Manufacturers Association
- U.S. Military connector specifications for military equivalents
- Water Resistant mark on wrist watches and eye bands
- Understanding the IP (Ingress Protection) Ratings
- Interpreting the acronym officially in the standard text
- IEC 60529 (ed2.1), clause 4.1.
- IEC 60529: Degrees of protection provided by enclosures (IP Code). International Electrotechnical Commission, Geneva.
- IP Ratings vs. NEMA Ratings
- Ingress Protection: The System of Tests and Meaning of Codes.
- DIN 40050-9: Straßenfahrzeuge; IP-Schutzarten; Schutz gegen Fremdkörper, Wasser und Berühren; Elektrische Ausrüstung [Road vehicles; degrees of protection (IP-code); protection against foreign objects, water and impact; electrical equipment], May 1993. An English translation of the German original is available from DIN.
- "FAQ — Enclosures". NEMA. Retrieved 2010-03-03.
- IEC Home Page
- IEC Web Store (buy IEC standards online)
- USA IP ratings
- Australian IP ratings
- NEMA vs IP Rating
- IP Rating information[dead link]
- IP Rating Illustrated Chart
- IP Ratings Explained
- Rugged Electronic Devices and Measurement of Ruggedness: A guide to deciphering ruggedness claims in cell phones, Smart Phones, PDAs &c (PDF), Airo Wireless.
- A demonstration of an IP test being carried out, YouTube.