Dark macro shot of a case gasket and pressure relief valve

Guide

Waterproof Case and IP Rating Guide

IP ratings, gaskets, pressure valves, submersion limits, and long-term waterproof maintenance.

Overview

Practical guidance

"Waterproof" is a loose word. The precise version is an IP rating, a two-digit code that describes dust and water protection under defined lab conditions. This guide explains the terms, what the ratings actually cover, and how gaskets and pressure valves keep a case sealed.

Water-resistant vs watertight vs waterproof

Water-resistant handles splashes and light rain. Watertight resists water intrusion under specific conditions. Waterproof, in the strict sense, means a case remains sealed under defined immersion, always tied to an IP rating and a time and depth limit.

How gaskets work

A continuous elastomer gasket sits in a channel around the case perimeter. Latches compress the lid against the gasket to form a seal. Damaged, dirty, or dried-out gaskets are the most common cause of a case losing its rating.

Pressure relief valves

Automatic pressure valves equalize the pressure difference between inside and outside the case as altitude or temperature changes. Without one, a sealed case pressurizes or vacuums and becomes difficult to open, or leaks past the gasket.

Reference

IP rating quick reference

Rating	Meaning
IP54	Dust-protected, splash-resistant
IP65	Dust-tight, resists water jets
IP66	Dust-tight, resists powerful water jets
IP67	Dust-tight, temporary immersion (1 m for 30 min)
IP68	Dust-tight, continuous immersion (manufacturer-defined depth and time)

IP ratings are tested under specific lab conditions and do not guarantee performance in every real-world scenario.

Note

Maintain the seal

Clean the gasket with mild soap and water, inspect for cracks or debris, and apply a food-grade silicone conditioner periodically to keep the seal supple.