In demanding operational environments, ensuring that equipment can withstand exposure to dust and water is crucial. The Ingress Protection (IP) rating system, defined by the International Electrotechnical Commission (IEC), provides a standardized method to classify the degrees of protection offered by enclosures of electrical equipment against the intrusion of solid objects and liquids.
Introduction
Rugged computers are built to withstand demanding environments, but not all are created equal. Each device is engineered for specific tasks and operating conditions, which means their level of ruggedness can vary significantly. So how do you tell the difference? One of the most reliable ways is by looking at the IP rating (Ingress Protection rating).
Whether you are selecting equipment for consumer use, industrial settings, or mission-critical defense applications, it’s essential to know how well a device is protected against dust and water. IP ratings provide a clear, standardized way to measure that protection.
This guide explains what IP ratings mean, how to interpret them, and the key differences between IP65, IP67, and IP68, helping you make informed choices for your operational environment.
What is an IP Rating?
An IP rating (Ingress Protection rating) is defined by the international standard IEC 60529. It classifies how effectively an enclosure protects electrical equipment against:
- Solid particles such as dust, sand, or tools.
- Liquids such as rain, splashes, jets, or immersion.
The code always starts with IP, followed by two digits:
- The first digit shows protection against solids (0–6).
- The second digit shows protection against liquids (0–9).
- An “X” means no test performed for that category.
IP Rating Breakdown
Solids (first digit)
| Digit | Protection level | Example |
|---|---|---|
| 0 | No protection | – |
| 1 | Objects ≥ 50 mm | Hand contact |
| 2 | Objects ≥ 12.5 mm | Finger |
| 3 | Objects ≥ 2.5 mm | Tools, thick wires |
| 4 | Objects ≥ 1 mm | Screws, small tools |
| 5 | Dust-protected | Limited dust ingress |
| 6 | Dust-tight | Complete dust seal |
Liquids (second digit)
| Digit | Protection level | Example |
|---|---|---|
| 0 | No protection | – |
| 1 | Dripping water | Vertical drops |
| 2 | Dripping water (tilted 15°) | Light rain |
| 3 | Spraying water | Up to 60° angle |
| 4 | Splashing water | From any direction |
| 5 | Water jets | Low-pressure jets |
| 6 | Powerful jets | High-pressure water |
| 7 | Temporary immersion | Up to 1 m, 30 min |
| 8 | Continuous immersion | Depth & time specified by manufacturer |
| 9K | High-pressure, high-temperature jets | Industrial cleaning |
Key Ratings Explained
IP65 – Dust-tight and protected against water jets
- Solids: 6 – Complete protection against dust.
- Liquids: 5 – Resistant to low-pressure water jets from any direction.
- Use cases: Typical use cases include outdoor lighting and enclosures exposed to rain; moreover, this rating suits equipment that may face splashing water but not immersion.
IP67 – Dust-tight and resistant to immersion
- Solids: 6 – Dust-tight.
- Liquids: 7 – Can withstand temporary immersion in water (up to 1 m for 30 minutes).
- Use cases: Smartphones, portable electronics, marine equipment, devices at risk of accidental submersion.
IP68 – Dust-tight and immersion-ready
- Solids: 6 – Dust-tight.
- Liquids: 8 – Designed for continuous immersion under conditions defined by the manufacturer (depth, duration).
- Use cases: Professional cameras, underwater sensors, ruggedized military electronics, permanently submerged equipment.
Choosing the Right IP Rating
When deciding on an IP rating, consider:
- Environment: Dusty factory floor? Marine environment? Outdoor installation?
- Exposure: Occasional rain vs. frequent submersion.
- Maintenance: Gaskets and seals wear over time; ratings assume devices are intact and properly closed.
- Balancing cost and need: While higher protection usually comes at a higher price, it is most effective to select the rating that aligns with your operational environment, ensuring mission reliability without adding unneeded cost.
Common Misconceptions
- “Waterproof” ≠ invincible. IP67 doesn’t mean the device survives a pressure washer.
- IP68 varies. Always check manufacturer specifications for depth and duration.
- Dust-tight is critical. For many environments, dust protection is as important as water resistance.
FAQs
Q: Is IP68 always better than IP67?
A: Not necessarily. If a product will never be submerged, IP67 or even IP65 might be sufficient and more cost-effective.
Q: What does IP69K mean?
A: Protection against high-pressure, high-temperature water jets, often used in industrial cleaning.
Q: Can IP65 devices stay outside year-round?
A: They resist rain and dust, but freezing, UV exposure, and long-term wear may reduce performance.
Summary
- IP65: Dust-tight + water jets.
- IP67: Dust-tight + temporary immersion.
- IP68: Dust-tight + continuous immersion (conditions vary).
Understanding IP ratings helps you select the right device for your environment, whether it’s consumer electronics, industrial machinery, or defense technology.