Buying
Waterproof ratings
Waterproof is a marketing word. The rating codes behind it are specific, and the difference between two of them decides whether an object can be rinsed properly.
Ingress protection codes take the form IP followed by two characters. The first describes protection against solid objects and is usually replaced by an X in this category, since dust is not the concern. The second describes water, and it is the one worth reading.
The codes that appear
| Rating | Meaning | Practical result |
|---|---|---|
| IPX4 | Splashing from any direction | Wipe and rinse briefly, never submerge |
| IPX5 | Low pressure water jets | Rinse under a tap, still not for a bath |
| IPX6 | Strong water jets | Rinse thoroughly, not for extended submersion |
| IPX7 | Immersion to one metre for thirty minutes | Wash properly, bath use is fine |
| IPX8 | Immersion beyond one metre, as stated by the maker | Anything the maker states |
Why the port decides
A shell with a hole in it cannot be sealed to IPX7 without a cover, and covers get left open. That is the main reason objects that charge through an open socket top out at splash resistance. Magnetic contacts on a closed shell allow a genuinely sealed object, and induction charging removes the last opening entirely.
Seals age
Rubber seals harden and shrink over years, and a rating measured in a factory does not come with a guarantee for the fifth year. An object that has been dropped, or that has had its head removed repeatedly, deserves more caution than its printed rating suggests. Condensation visible inside a shell means the seal has already failed.
Cleaning consequences
A submersible object can be washed properly, held under a tap, filled and emptied, and boiled where the material allows. A splash resistant one has to be wiped, which is a meaningfully worse standard of cleaning for anything used internally. Over a year, that difference is the strongest argument for choosing a sealed design, and it is the reason the cleaning page treats the two separately.
Bath and shower use adds one more consideration. Water washes away a water based lubricant almost immediately, so a silicone formula is the practical choice there, subject to the material rule set out on the compatibility page.
Where the rating is tested
Ratings are measured on a new object at room temperature with fresh water. Real use involves warm water, soap, lubricant residue and a shell that has been dropped at least once. None of those appear in the test, which is a reason to treat the rating as a ceiling rather than a promise, particularly on an object several years old.