| Full title | Degrees of protection provided by enclosures (IP Code) |
| Publisher | IEC (TC 70); adopted as EN 60529 by CENELEC and as BS EN 60529 by BSI |
| Current IEC edition | IEC 60529:1989+AMD1:1999+AMD2:2013 consolidated version (edition 2.2), including the corrigendum of January 2019 |
| Current BSI version | BS EN 60529:1992+A2:2013, incorporating the corrigendum of February 2019. Status: Current |
| Related standards | ISO 20653 (road vehicles, K codes); IEC 61076-2 series connector specifications cite IEC 60529 |
What it covers
IEC 60529 sets out a system for classifying the protection an enclosure gives to electrical equipment. The IP code describes three things: protection of people against access to hazardous parts, protection of the equipment against solid foreign objects, and protection against harmful ingress of water.
It defines the code, the requirements for each degree and the tests used to check them. Product standards then decide which degrees apply to a product and any extra details of the test.
The code is written as IP followed by two characteristic numerals, then optional letters. Where a numeral is not specified, it is replaced by the letter X, as in IPX7.
First numeral: solids and access
| Numeral | Solid objects | Access to hazardous parts | Test |
|---|---|---|---|
| 0 | Not protected | Not protected | None |
| 1 | 50 mm and greater | Back of hand | 50 mm sphere must not fully penetrate |
| 2 | 12.5 mm and greater | Finger | 12.5 mm sphere; jointed test finger 12 mm diameter, 80 mm long |
| 3 | 2.5 mm and greater | Tool | 2.5 mm probe must not penetrate |
| 4 | 1.0 mm and greater | Wire | 1.0 mm probe must not penetrate |
| 5 | Dust-protected | Wire | Talcum dust chamber; dust must not enter in a quantity that interferes with operation or impairs safety |
| 6 | Dust-tight | Wire | Talcum dust chamber; no deposit of dust observable inside |
The dust test
The dust chamber uses talcum powder at 2 kg per cubic metre of chamber volume. Enclosures are split into two categories:
- Category 1: enclosures where normal operation causes a pressure below ambient, for example through thermal cycling. A vacuum pump draws 80 enclosure volumes of air through the enclosure, at no more than 60 volumes per hour and a depression of no more than 2 kPa (20 mbar). The test lasts 2 h at 40 to 60 volumes per hour, otherwise until 80 volumes have been drawn or 8 h have passed.
- Category 2: enclosures with no pressure difference. The test runs for 8 h without a vacuum pump.
- IP5X is tested as category 1 unless the product standard says category 2. IP6X is always tested as category 1.
Second numeral: water
| Numeral | Protected against | Main test conditions |
|---|---|---|
| 0 | Not protected | None |
| 1 | Vertically falling drops | Drip box, 10 min on a turntable at 1 r/min |
| 2 | Drops with enclosure tilted up to 15° | Drip box, 2.5 min in each of four 15° tilted positions |
| 3 | Spraying water up to 60° from vertical | Oscillating tube (5 min, then turned 90° for 5 min) or spray nozzle at 10 l/min |
| 4 | Splashing water from any direction | Oscillating tube (10 min) or spray nozzle at 10 l/min |
| 5 | Water jets | 6.3 mm nozzle, 12.5 l/min, 2.5 m to 3 m, at least 3 min |
| 6 | Powerful water jets | 12.5 mm nozzle, 100 l/min, 2.5 m to 3 m, at least 3 min |
| 7 | Temporary immersion | 30 min; lowest point 1 m below the surface (enclosures under 850 mm high) |
| 8 | Continuous immersion | By agreement between manufacturer and user, but more severe than for numeral 7 |
| 9 | High-pressure, high-temperature jets | Fan jet nozzle, (15 ± 1) l/min, (80 ± 5) °C, (175 ± 25) mm |
Spray nozzle tests for numerals 3 and 4 run for 1 min per square metre of enclosure surface, with a minimum of 5 min.
Immersion does not imply jet protection
Compliance with lower numerals is implied only up to numeral 6. An enclosure marked only IPX7 or IPX8 (or only IPX9) is classed as ‘restricted’: it is considered suitable only for the conditions it was tested to. Where both jet and immersion protection are claimed, the enclosure is multiple coded, for example IPX5/IPX7 or IPX6/IPX8/IPX9. Check for both codes where a product will be both hosed down and submerged.
Additional and supplementary letters
| Letter | Type | Meaning |
|---|---|---|
| A | Additional | Protected against access with the back of a hand (50 mm sphere) |
| B | Additional | Protected against access with a finger (12 mm jointed finger, 80 mm long) |
| C | Additional | Protected against access with a tool (2.5 mm probe, 100 mm long) |
| D | Additional | Protected against access with a wire (1.0 mm probe, 100 mm long) |
| H | Supplementary | High-voltage apparatus |
| M | Supplementary | Water test made with moving parts in motion |
| S | Supplementary | Water test made with moving parts stationary |
| W | Supplementary | Suitable for specified weather conditions, with extra protective features or processes |
IPX9 and IP69K
IPX9 was added to IEC 60529 by Amendment 2 in 2013. The amendment introduced the new degree without changing any existing ones. Small enclosures (under 250 mm) sit on a turntable at 5 r/min and are sprayed at 0°, 30°, 60° and 90°, for 30 s in each position. Large enclosures are sprayed from all practical directions for 1 min per square metre, with a minimum of 3 min. The jet’s impact force must be verified at both ends of the distance tolerance.
IP69K is not an IEC 60529 code. The K codes come from road-vehicle practice and are now defined in ISO 20653, which replaced the German standard DIN 40050-9:1993 (now withdrawn). ISO 20653 states that its IP codes follow IEC 60529 except the K codes, which cover road-vehicle needs not covered by IEC 60529. Code 9K covers water from high-pressure or steam-jet cleaning.
The current edition is ISO 20653:2023 (edition 3), which replaced the 2013 edition. It extended the IPX9K test conditions and described how the impact force is measured. ISO lists it as under revision.
IPX9 and IPX9K are separate tests in separate standards. A claim of one is not a claim of the other.
What it means in practice
- The IP code applies to the enclosure as tested. For connectors, check whether the rating applies when mated, unmated, or with a protective cap fitted.
- Look for the full code, including any X, letters and multiple codes. IP67 does not include IP65 or IP66 unless both are stated.
- For washdown areas, check which test the supplier used: IPX9 to IEC 60529 or IPX9K to ISO 20653.
- Impact resistance is not part of the IP code.
Related reading: IP ratings explained: IP67, IP68 and IP69K.