What Is IP (Ingress Protection) Rating?
IP (Ingress Protection) Rating is a two-digit number that indicates protection level of electronic equipment. IP rating aims to provide users more detailed information than unclear marketing terms such as hermitically sealed or waterproof.
As defined in international standard IEC 60529 (specified in Australian Standards AS60529 and EN60529), IP Code classifies and rates the degrees of protection provided against the intrusion of solid objects, dust, accidental contact, and water in electronic equipment or mechanical casings with electrical enclosures.
The two digits (characteristic numerals) of IP rating code 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.
The two digits represent different forms of environmental influence:
- The first digit represents protection against ingress of solid objects
- The second digit represents protection against ingress of liquids
The larger the value of the digit, the greater is the protection from that influence.
Table 1: IP protection rates
|Value||First Digit||Second Digit|
|Protection against ingress of solids||Protection against ingress of liquids|
|No protection||No protection|
|Protected against solid objects over 50mm e.g. hands, large tools||Protected against vertically falling drops of water.|
|Protected against solid objects over 12mm e.g. hands, large tools||Protected against direct sprays of water up to 15° from vertical.|
|Protected against solid objects over 2.5mm e.g. wire, small tools||Protected against direct sprays of water up to 60° from vertical.|
|Protected against solid objects over 1.0mm e.g. wires||Protected against water sprayed from any direction. Limited ingress permitted.|
|Limited protection against dust ingress (no harmful deposit)||Protected against low pressure water jets from any direction. Limited ingress permitted.|
|Totally protected against dust ingress.||Protected against high pressure water jets from any direction. Limited ingress permitted.|
|—||Protected against immersion between 15cm and 1M.|
|—||Protected against long periods of immersion under pressure.|
A few examples:
- 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.
- A product rated as IP57 would be better protected against environmental factors than another similar product that was only rated as IP43.
- All of submersible sensors are required to have IP rating of 67 or 68.
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. This is more common in food and pharmaceutical applications.