IP protection level analysis: What do IP65, IP67, and IP68 mean respectively?
IP protection levels consist of two digits representing protection against solid foreign objects and protection against liquids. Only by understanding the IP rating can you choose protection specifications for industrial equipment that truly match the on-site environment.
Specifications for industrial PCs, industrial panel displays, sensors, and other industrial devices frequently list ratings like "IP65," "IP67," or "IP68." What do these numbers actually mean? Which level should you look for when selecting equipment? This article provides a detailed breakdown.
What Is an IP Rating?
IP (Ingress Protection) ratings are defined by international standard IEC 60529, in the format IP XY:
- X (first digit): Protection against solid particle ingress, levels 0–6
- Y (second digit): Protection against liquid ingress, levels 0–9K
When a digit is replaced with "X," it means that aspect was not tested or is not applicable — for example, "IPX7" indicates only the water ingress test was performed, with no dust rating claimed.
First Digit: Solid Particle Protection
| Level | Protection |
|---|---|
| 0 | No protection |
| 1 | Protection against >50mm objects (hand) |
| 2 | Protection against >12.5mm objects (finger) |
| 3 | Protection against >2.5mm objects (tools) |
| 4 | Protection against >1mm objects (wire) |
| 5 | Dust protected (limited dust ingress, no harmful deposit) |
| 6 | Dust tight (no dust ingress whatsoever) |
Second Digit: Liquid Protection
| Level | Test Condition | Protection |
|---|---|---|
| 0 | — | No protection |
| 1 | Vertical drip | Vertically falling drops |
| 2 | 15° tilted drip | Slightly angled dripping |
| 3 | Spray up to 60° | Rainfall/spraying |
| 4 | Splash from any direction | Water splashing |
| 5 | Low-pressure water jet | Low-pressure hosing |
| 6 | High-pressure water jet | Powerful water jets |
| 7 | Short immersion (1m/30min) | Temporary submersion |
| 8 | Continuous immersion (per manufacturer spec) | Continuous submersion |
| 9K | High-pressure steam jet (80°C / 80–100 bar) | High-temp pressure wash |
What Common Ratings Mean in Practice
- IP54: Dust protected (limited ingress) + splash from any direction. Suitable for mildly dusty indoor industrial environments with occasional water mist.
- IP65: Dust tight + low-pressure water jet resistance. The most common rating for industrial PC front panels — suitable for food processing, chemical plants, and other areas that require periodic hose-down cleaning.
- IP67: Dust tight + temporary immersion to 1m for 30 minutes. Suitable for environments with standing water or occasional submersion risk.
- IP68: Dust tight + continuous immersion to manufacturer-specified depth and duration. For underwater equipment or permanently flooded environments.
- IP69K: Dust tight + resistance to 80°C high-pressure steam jets. Primarily for food, pharmaceutical, and beverage production equipment that requires hot steam sterilization cleaning.
Important Caveats
1. IP ratings apply to the tested component, not necessarily the whole unit: An "IP65 front panel" on an industrial PC means only the front panel meets this rating. Rear connector panels typically do not share the same protection — do not submerge the full unit;
2. IP rating ≠ corrosion resistance: IP testing uses clean water. It does not imply resistance to salt spray, acids, bases, or cleaning chemicals. Chemical and marine environments require separate assessment of material corrosion resistance;
3. Seals degrade over time: Rubber gaskets age under temperature, UV exposure, and chemical contact, gradually reducing protection effectiveness. Regular inspection and replacement are necessary;
4. IP67 ≠ IP68 (they are not a progression): A device that passes IP68 testing does not necessarily pass IP67, because the test methods differ. Always match the rating to your actual scenario rather than assuming higher numbers are strictly better.