CENELEC and IEC Degree of Protection, IP Code
The standards EN 60529 and IEC 60529 describe a system for classifying the degrees of protection provided by the enclosures of electrical equipment as follows:
| First Number | Second Number | ||||||
|---|---|---|---|---|---|---|---|
| Code Number | Icon | Protection | Description | Code Number | Icon | Protection | Description |
| 0 | Non-protected. | Protection of persons against access to hazardous parts inside the enclosure and against solid foreign objects. | 0 | Non-protected | Protection of the equipment inside the enclosure against harmful effects due to the ingress of water. | ||
| 1 | Protected against objects of 50mm diameter and greater. | An object probe, sphere of 50mm diameter, shall not fully penetrate. | 1 | Protected against vertically falling water drops. | Vertically falling drops shall have no harmful effects. | ||
| 2 | Protected against solid foreign objects of 12.5mm diameter and greater. | An object probe, sphere of 12.5mm diameter, shall not fully penetrate. | 2 | Protected against vertically falling water drops when enclosure tilted up to 15°. | Vertically falling drops shall have no harmful effects when the enclosure is tilted at any angle up to 15° on either side of the vertical. | ||
| 3 | Protected against solid foreign objects of 2.5mm diameter and greater. | An object probe, sphere of 2.5mm diameter, shall not penetrate at all. | 3 | Protected against spraying water. | Water sprayed at an angle up to 60° on either side of the vertical shall have no harmful effects. | ||
| 4 | Protected against solid foreign objects of 1.0mm diameter and greater. | An object probe, sphere of 1.0mm diameter, shall not penetrate at all. | 4 | Protected against splashing water. | Water splashed against the enclosure from any direction shall have no harmful effects. | ||
| 5 | Dust-protected. | Ingress of dust is not totally prevented, but dust shall not penetrate in a quantity to interfere with satisfactory operation of apparatus or to impair safety. | 5 | Protected against water jets. | Water projected in jets against the enclosure from any direction shall have no harmful effects. | ||
| 6 | ![]() |
Dust-tight. | No ingress of dust. | 6 | Protected against powered water jets. | Water projected in powerful jets against the enclosure from any direction shall have no harmful effects. | |
| Typical Designation : IP66 | 7 | Protected against the effects of temporary immersion in water. | Ingress of water in quantities causing harmful effects shall not be possible when the enclosure is temporarily immersed in water under standardised conditions of pressure and time. | ||||
| 8 | Protected against the effects of continuous immersion in water. | Ingress of water in quantities causing harmful effects shall not be possible when the enclosure is continuously immersed in water under conditions which shall be agreed between manufacturer and user but which are more severe than for numeral 7. | |||||
Deluge Ingress Protection
On offshore facilities, equipment may be located in areas subject to emergency deluge systems. Equipment that has been evaluated as certified for use in hazardous areas may not be suitable for use in these locations. A testing method for electrical equipment to be installed in areas subject to deluge systems, DTS01, has been prepared by the Explosion and Fire Hazards Group of ERA Technology (now known as ITS) in collaboration with Shell UK Exploration and Production Ltd.
Testing includes:
- Energising the equipment (where appropriate) for 60 minutes prior to the deluge test, then interrupting the electrical power at the start of the deluge test and resuming after 60 minutes until the completion of the deluge test.
- Carrying out insulation resistance testing before and after pre-conditioning and after the deluge test, where applicable.
- Carrying out pre-conditioning by exposure to vibration and thermal ageing at 90% relative humidity and at a temperature 20k above the equipments maximum service temperature and/or at least 80°C of any appropriate seals.
- Carrying out deluge test using a deluge chamber fitted with deluge nozzles that apply a salt water solution deluge pressure within the range of 3.5 bar to 4.5 bar at a water temperature in the range of 5°C to 10°C for 3-hours.
