What Is an IP Rating?

Many electronic devices now come with an IP rating for dust and water protection. What does it mean and how should you read it? Different ratings show different levels of protection against these potentially dangerous intrusions. Reading an IP rating is very easy.

IP rating stands for Ingress Protection rating or International Protection marking, depending on who you ask. It defines a level of protection against intrusion from both solids and liquids, but also against general objects such as fingers and tools.

First, you need to understand the general format:

IP<solid><liquid>
Example: IP68

With <solid> representing the resistance to the intrusion of “solid” objects (fingers, dust…), and <liquid> being the protection against liquids (typically, water). You can look at the table below and from there, you will be able to read any IP ratings.

IP44 means that the device is protected from small tools and wires (~1mm) and protected against water splash from any direction. Tested for 5mn at 10L/mn at 50-150 kPa.

IP66 means that a device is dust-tight: no dust can penetrate. It is also protected against strong water jets (~12.5mm nozzle) won’t harm the device. 3mn test, 100L/mn at 100 kPa, 3 meters away. It is not submersible.

IP67 means that a device is dust-tight: no dust can penetrate. It can withstand up to 1-meter immersion for a limited duration won’t harm the device. Tested for 30mn

IP68 means that the solid IP rating is 6, and the liquid rating is 8: Dust-tight – no dust can penetrate. Beyond 1-meter immersion waterproofing. In some cases, waterproofing means that some water can penetrate, but without harming the device.

IP Rating	Solids intrusion (IPX_)	Liquids intrusion (IP_X)

0	No protection	No protection
1	Protected against contact with large surfaces of the body, but doesn’t prevent voluntary contact (~50mm)	Protects against dripping water (falling vertically) when in a vertical position. Tested during 10 minutes, equivalent to 1mm/mn rainfall. No water immersion.
2	Protected from finger-sized objects (~12.5mm)	Protects against dripping water up to a 15 degrees angle. Testing during 10mn, equivalent to 3mm/mn rain. No water immersion.
3	Protected from large tools (~2.5mm)	Protects against sprayed water at an angle of up to 60 degrees (from the vertical). Tested for 5mn at 0.7L/mn at a pressure of 50-150 kPa. No water immersion.
4	Protected from small tools and wires (~1mm)	Protected against water splash from any direction. Tested for 5mn at 10L/mn at 50-150 kPa
5	Prevents a moderate amount of dust from entering but is not Dust-tight	Water jets (~6.3mm nozzle) won’t harm the device. 3mn test at 100L/mn at 30 kPa, 3 meters away. No water immersion.
6	Dust-tight: no dust can penetrate	Strong water jets (~12.5mm nozzle) won’t harm the device. 3mn test, 100L/mn at 100 kPa, 3 meters away. No water immersion.
7	N/A	Up to 1-meter immersion for a limited duration won’t harm the device. Tested for 30mn
8	N/A	More than 1-meter immersion waterproofing. In some cases, waterproofing means that “some” water can penetrate, but without harming the device. Each OEMs can define a specific depth limit
9K	N/A	Hot (80C) waterjets test with a volume of 14-16L/mn at a pressure of 8000-10000 kPa at a close range of 1cm to 15cm