IP65, IP66, IP67 and IP68 Explained: Waterproof Does Not Mean Salt-Spray Resistant

The IP rating only answers “protection against solid particles and water entering the enclosure” and does not automatically represent corrosion resistance, high pressure resistance, condensation resistance or marine grade. Many outdoor projects mix these concepts together to create a selection bias.

What do the two numbers stand for?

The first digit after the IP represents the anti-solid particle rating and the second digit represents the waterproof rating. IP65 and IP66 are usually used for outdoor dustproof and waterproof/strong water spraying; IP67 involves short-term water immersion, and IP68 is used for higher-level continuous water immersion under factory specified conditions. Depth and timing will still depend on the product description.

IP68 does not equal 1MPa pipe pressure

Immersion protection tests and pressure vessel conditions are not the same thing. When the water quality probe is installed in the pressurized pipe, it should look at clear working pressure parameters, threaded connections and sealing materials, not just IP68.

Also see salt spray and materials on the seashore

Salt spray can corrode fasteners, brackets, connectors, and PCBs. Even with the enclosure IP65, prolonged sea breezes and condensation increase the risk. Marine projects require additional consideration of stainless steel grades, coatings, triple lacquer, connectors and maintenance cycles.

High humidity does not equal condensation

“0–95%RH” generally refers to a non-condensing environment. After the temperature drop forms water droplets, the equipment is subjected to liquid water and surface conductive pollution, and the risk is different from that of purely high RH.

FAQ

Q1: Can IP65 get wet?

A1: Generally, it can be used in outdoor rainproof and water spray environments, but it is still necessary to ensure that the interface, cable inlet and protective box are properly sealed during installation.

Q2: Can IP68 be buried?

A2: If the probe body is clearly IP68, it is generally suitable for embedding/immersion, but the cable connector and transmitter should still be installed as instructed.

Q3: Is IP68 enough for the seaside?

A3: Not enough, also consider salt spray corrosion, UV rays, materials and maintenance.