An IP (Ingress Protection) rating has two digits. The first digit (0-6) indicates protection against solid objects, from no protection to dust-tight. The second digit (0-9) indicates protection against water, from no protection to high-pressure steam cleaning. IP65 means dust-tight and protected against water jets. IP67 means dust-tight and protected against temporary immersion.
The standard: IEC 60529
IP ratings are defined by IEC 60529 (and its European equivalent EN 60529). The standard specifies test methods and requirements for classifying the degree of protection provided by enclosures of electrical equipment. It was first published in 1976 and has been updated several times, with the current edition from 2013.
The "IP" stands for Ingress Protection (or International Protection, depending on who you ask). The two-digit code that follows tells you exactly what can and cannot get into the enclosure.
The first digit: solid object protection
The first digit ranges from 0 to 6 and indicates the level of protection against solid foreign objects and access by persons.
| Digit | Protection level | Object size | Test |
|---|---|---|---|
| 0 | No protection | -- | No test |
| 1 | Protected against objects >50mm | Back of hand | 50mm sphere, no full contact with live parts |
| 2 | Protected against objects >12.5mm | Finger | 12.5mm diameter, 80mm length probe |
| 3 | Protected against objects >2.5mm | Tools, thick wires | 2.5mm diameter probe |
| 4 | Protected against objects >1mm | Most wires, small screws | 1mm diameter probe |
| 5 | Dust-protected | Limited dust ingress | Dust chamber, 8 hours, functionality not impaired |
| 6 | Dust-tight | No dust ingress at all | Dust chamber, 8 hours, vacuum applied, no ingress |
The distinction between 5 and 6 is significant. "Dust-protected" (5) allows some dust to enter but not enough to interfere with the equipment's operation. "Dust-tight" (6) allows no dust at all. For electrical equipment in industrial environments, IP5X is usually sufficient. IP6X is required in food processing, pharmaceutical, and clean room applications.
The second digit: water protection
The second digit ranges from 0 to 9K and indicates the level of protection against water ingress.
| Digit | Protection level | Test description |
|---|---|---|
| 0 | No protection | No test |
| 1 | Dripping water | Vertical drops, 10 min, 1mm/min rainfall equivalent |
| 2 | Dripping water at 15 degree tilt | Vertical drops with enclosure tilted 15 degrees |
| 3 | Spraying water | Water spray at up to 60 degrees from vertical |
| 4 | Splashing water | Water splashed from all directions |
| 5 | Water jets | 6.3mm nozzle, 12.5 liters/min at 3 meters |
| 6 | Powerful water jets | 12.5mm nozzle, 100 liters/min at 3 meters |
| 7 | Temporary immersion | Submerged to 1 meter for 30 minutes |
| 8 | Continuous immersion | Submerged beyond 1 meter, conditions specified by manufacturer |
| 9K | High-pressure/steam cleaning | 80 degree Celsius water at 80-100 bar at close range |
Important: the tests are not cumulative between groups. An enclosure rated IP67 has been tested for dust-tightness and temporary immersion. It has not necessarily been tested for water jets (the IPX5/IPX6 test). In practice, an IP67-rated product will survive a water jet, but technically the manufacturer only certifies the IP67 test. If both jet and immersion protection are required, the rating is written as IP65/IP67, meaning the product has been tested and certified for both.
The X placeholder
When a digit is replaced with X, it means that characteristic was not tested. IPX4 means water splash protection was verified but solid object protection was not tested. IP5X means dust protection was verified but water protection was not tested.
You will frequently see IPX4 and IPX7 in product data for luminaires and consumer-adjacent electrical products. The X does not mean "no protection." It means "not rated."
Optional letters
IEC 60529 defines additional letters that can follow the two digits:
Supplementary letters (after the second digit)
| Letter | Meaning |
|---|---|
| H | High-voltage equipment |
| M | Device was moving during water test |
| S | Device was stationary during water test |
| W | Specified weather conditions |
Access protection letters (replacing or supplementing the first digit)
| Letter | Protection against access with |
|---|---|
| A | Back of hand (50mm sphere) |
| B | Finger (12mm, 80mm length) |
| C | Tool (2.5mm diameter) |
| D | Wire (1mm diameter) |
In practice, you will rarely see the supplementary letters in electrical distribution product data. They appear primarily in test reports and detailed technical documentation.
Common IP ratings in electrical products
IP20: Indoor, clean environments
Standard for DIN rail components (circuit breakers, contactors, terminals) mounted inside a closed enclosure. The enclosure provides the environmental protection; the component itself only prevents finger contact.
IP44: Indoor, protected areas
Common for flush-mounted switches and sockets in dry indoor environments. Protected against splashing water and objects larger than 1mm.
IP54: Indoor industrial
Dust-protected and splash-proof. Standard for motor starters, industrial controls, and indoor junction boxes. Sufficient for most factory environments that are not routinely hosed down.
IP55: Industrial wash-down areas
A step up from IP54 with water jet protection. Used in food and beverage processing areas where equipment is cleaned with hoses.
IP65: Outdoor, exposed locations
Dust-tight and jet-proof. The standard specification for outdoor luminaires, junction boxes, and weatherproof enclosures. Handles rain, wind-driven water, and hose cleaning.
IP66: Harsh outdoor and marine
Dust-tight with powerful jet protection. Specified for marine environments, industrial outdoor installations, and equipment exposed to high-pressure cleaning.
IP67: Temporary submersion
Dust-tight and submersion-proof. Used for equipment installed in locations subject to temporary flooding, or for portable equipment that might be dropped in water. Common for industrial sensors and connectors.
IP68: Permanent submersion
Dust-tight and continuously submerged. Used for underwater lighting, submersible pumps, and buried junction boxes. The depth and duration are specified by the manufacturer.
IP69K: High-pressure wash-down
The highest water protection level. Resists close-range high-pressure, high-temperature water jets. Required for food processing equipment that undergoes steam cleaning.
Validate any IP rating code with the free IP rating validator. It checks the format, validates both digits, and explains the protection level.
IP ratings in product data
IP rating is one of the most searched and filtered attributes in electrical product catalogs. Getting it right matters for two reasons:
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Specification compliance. Engineers specify minimum IP ratings in project specifications. A search for "IP65 junction box" must return products that meet or exceed that rating.
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Faceted search. Customers filter by IP rating on your webshop. If the data is inconsistent (some products have "IP65," others have "IP 65," others have "65"), the filter breaks.
Normalize IP ratings to the format "IP" followed by two digits, no spaces: IP54, IP65, IP67. Validate that both digits fall within the allowed ranges. Use the IP rating validator to check your entire catalog.