IP rating, Ingress Protection Rating or International Protection Rating indicates the level of protection to which a product is protected against the intrusion of solid objects or dust, accidental contact and water.

IP rating specifies the level of environmental protection for an enclosure of electrical equipment. The ingress protection rating is defined by the European Committee for Electrotechnical Standardisation and specifies the degree of environmental protection that an electrical or mechanical enclosure provides against the intrusion of solids and liquids. Solids may include dust, tools, screws, or accidental contact by hand or fingers. The liquids may be water from rain, moisture or stagnant water

The IP rating of an enclosure specifies the sealing effectiveness of a mechanical or electrical enclosure against intrusion from solids, liquids and other foreign bodies such as tools, dirt, moisture, etc.

The IP rating comprises two or three numbers:

1. The first number indicates the protection from solid materials or objects
2. The second number specifies the protection from liquids such as water
3. The third number indicates the protection against mechanical impacts, but is not commonly used; it is not a part of the IEC 60529

The ingress protection ratings are defined in the EN 60529 international standards, and each number in the IP rating has its standard meaning. The first number shows the degree of protection against solids, while the second number indicates the level of protection against liquids, which can either be in drips, sprays, moisture, rain at different angles, submersion, etc.

A digit indicates the level of protection, with a 0 (zero) rating indicating that there is no protection, while a higher digit means more protection. If the equipment ingress protection data is not available, an X is used.

A greater IP rating number signifies more protection, and a product rated IP54 means it has more protection against environmental factors compared to a similar product rated as IP42.

The ingress protection rating provides users with more detailed information compared to the general marketing terms such as waterproof or dustproof. The digits in the rating, as summarised in the IP Rating chart in Figure 1 above, conform to international standards and are, therefore, applicable everywhere.