Understanding IP Ratings: From IP20 to IP68 and Their Applications

What IP rating is required for outdoor use: under a canopy or in unheated enclosures – no less than IP44; outdoors in the rain – IP65 or higher; for locations where immersion in water is possible – IP67/IP68. Below, we explain what each digit in the code means and how to select the correct rating based on environmental conditions.

The IP (Ingress Protection) code (EN/IEC 60529) consists of two digits following the letters IP: the first (0–6) indicates the degree of protection of the enclosure against solid objects and dust, and the second (0–9) indicates protection against water. The higher the digit, the more stringent the test conditions: IP20 provides protection only against fingers and objects larger than 12.5 mm, IP54 indicates a dust-protected enclosure resistant to splashing water, and IP68 allows for continuous immersion.

A practical rule of thumb is as follows: dry indoor environments – IP20; bathrooms or outdoor areas under a canopy – IP44; exposed outdoor areas – IP65 or higher; and water immersion – IP67/IP68. The IP code does not characterise mechanical strength; this is covered by a separate IK code.

What the IP code means

IP (Ingress Protection) is the international standard (EN/IEC 60529) that defines the degree of protection provided by an enclosure for electrical equipment against the ingress of solid objects and water. The code consists of two characteristic digits: IPXY, where X represents protection against access to hazardous parts and solid objects (0–6), and Y represents protection against water (0–9). These may be followed by additional letters (such as A, B, C, or D for protection against access to hazardous parts) or supplementary letters (such as H, M, S, or W, where W denotes protection under specific weather conditions).

The first digit – protection against solids and dust

Digit	Protection against	Size
0	No protection	–
1	Large objects	> 50 mm (back of a hand)
2	Medium objects	> 12.5 mm (finger)
3	Small objects	> 2.5 mm (tool)
4	Small particles	> 1 mm (wire)
5	Dust (partial)	Dust does not interfere with operation
6	Dust (complete)	Dust-tight

The second digit – protection against water

Digit	Protection against	Test conditions
0	No protection	–
1	Vertical water drops	Drops falling vertically
2	Drops at a 15° angle	Enclosure tilted at 15°
3	Spraying water (rain)	Sprayed water (rain) at an angle up to 60° from vertical
4	Splashes	Splashes from all directions
5	Water jets	Water jet from any direction, 6.3 mm nozzle, flow rate of 12.5 l/min
6	Powerful water jets	Water jet from a 12.5 mm nozzle, flow rate of approx. 100 l/min
7	Temporary immersion	Depth up to 1 m, for 30 min
8	Continuous immersion	Depth and time – as specified by the manufacturer
9	High-pressure/high-temperature jets	Pressure 8–10 MPa, temperature 80 °C

The difference between IP65 and IP66 lies in the jet strength during testing: 12.5 l/min from a 6.3 mm nozzle versus 100 l/min from a 12.5 mm nozzle.

Furthermore, IP68 does not mean "better in every aspect": IPX7/IPX8 ratings confirm resistance to immersion, but do not guarantee resistance to water jets – these are different testing methodologies. Therefore, products that must withstand both jets and immersion are marked with a dual code, such as IP65/IP68.

Impact resistance: IK code

The mechanical resistance of an enclosure is denoted by a separate IK code according to EN/IEC 62262: from IK00 (no protection specified) to IK10 (20 J impact energy). For distribution boards on construction sites or in areas at risk of mechanical damage, the IK rating is the critical factor, not the IP rating: the IP degree of protection does not characterise mechanical strength.

Choosing an IP rating: operating conditions → minimum code

• Dry rooms (apartments, offices): IP20 – the standard for modular equipment, circuit breakers, and sockets
• Bathrooms according to HD 60364-7-701: Zone 0 (inside a bath or shower tray) – no lower than IPX7; Zones 1 and 2 – no lower than IPX4; in practice, sockets and switches are typically rated IP44 or higher
• Outdoor under a canopy: IP44 – for sockets, switches, and luminaires
• Industrial premises, outdoor enclosures: IP54–IP65 depending on dust and humidity levels
• Open outdoor areas without shelter: IP65 and higher – for luminaires, floodlights, and equipment used in car washes or food production
• Ship decks, open areas with heavy rain: IP66
• Temporary immersion (fountain lighting, underground utilities): IP67
• Continuous underwater operation (swimming pool lighting, submersible pumps): IP68

For a practical comparison of the differences between IP44 and IP54 for outdoor electrical enclosures, please see our article "IP44 vs IP54 Protection Ratings for Enclosures: Which to Choose for Outdoor Use".