IP 65, 66, 67 Ratings: What’s the Difference?

Ingress protection, or IP, standards dictate the level of water protection for equipment enclosures. Significant differences exist between water resistant, waterproof, and other labels—but what does each of the actual IP standards mean?

Key Takeaways 

• IP ratings (Ingress Protection) define the level of protection an enclosure or device provides against solids (like dust) and liquids (like water). 

• The first digit in an IP rating refers to solid particle protection, while the second digit indicates liquid ingress protection. 

• IP65: Dust-tight and protected against low-pressure water jets. 

• IP66: Dust-tight and protected against high-pressure water jets. 

• IP67: Dust-tight and protected against temporary immersion in water (up to 1 meter for 30 minutes). 

• Choosing the right IP rating depends on your environment, application, and exposure to moisture and dust. 

For starters, the International Electrotechnical Commission (IEC) sets the standards based on testing protocols and general requirements. For the sake of simplicity, we’ll focus on the differences between IP 65, IP 66 and IP 67. Each of these represents a slightly different level of water protection for enclosures.

Breaking Down the Numbers

First Digit: Solids.
As mentioned above, IP stands for “ingress protection.” The first digit represents protection against solids. A “6” means the enclosures are dust-tight. No dust enters the enclosure after significant, rigorous testing. It is the highest of the solid particle protection standards. 

Second Digit: Liquids. 
In simple terms, the higher the value of the second digit, the greater the level of protection from liquids. Summarized, each rating is as follows:

IP 65: Water projected from a nozzle from any direction shall have no harmful effects.

IP 66: Water projected in powerful jets from any direction shall have no harmful effects.

IP 67: Ingress of water in harmful quantity shall not be possible when the enclosure is immersed in water under defined conditions of pressure and time.

Testing details that lead to the above ratings are as follows:

Options Available from Transtector
Two-digit IP ratings range down to “00” (no protection from solids or liquids) up to the IP 67 enclosures offered by Transtector Systems and beyond. Again, in simple terms, the higher the numbers, the higher the level of protection. Contact Transtector today to determine which enclosure is best for your application, or learn more about our NEMA enclosures here.

FAQs (Frequently Asked Questions) 

Q1. What does “IP” stand for in IP ratings? 

A: “IP” stands for Ingress Protection, defined under the IEC 60529 standard. It measures how well electrical enclosures resist dust and water penetration. 

Q2. How are IP ratings tested? 

A: Testing involves exposing the product to standardized dust and water tests per IEC 60529 to verify it meets the specified protection level. 

Q3. Can IP65 devices be used outdoors? 

A: Yes, IP65 is suitable for outdoor use where equipment may face dust and light rain. However, if exposure to heavy water jets or immersion is expected, IP66 or IP67 is recommended. 

Q4. Is IP67 better than IP66? 

A: Not necessarily “better,” but different. IP67 is rated for temporary immersion, while IP66 handles high-pressure water jets. Choose based on your environment. 

Q5. Can I submerge an IP67-rated device permanently? 

A: No. IP67 allows temporary immersion (up to 30 minutes). For continuous submersion, you’ll need IP68 or IP69K-rated components. 

Q6. Which IP rating is best for industrial connectors? 

A: For industrial or outdoor connectors exposed to harsh conditions, IP66 or IP67 is typically ideal to ensure protection against both dust and heavy water exposure.