Guides · Use and care

Water resistance: ATM, bar and metres

ATM, bar and metres say the same thing: 1 ATM ≈ 1 bar ≈ 10 m. The number is a laboratory pressure, not a diving depth — a "100 m" watch has been tested at a static pressure of 10 bar, but a stroke of the arm in water causes pressure spikes, so the rule is: 3 ATM withstands splashes, 5 ATM showering, 10 ATM swimming and snorkelling, 20 ATM and above diving (proper dive watches follow the ISO 6425 standard and have a rotating bezel).

A screw-down crown is screwed against the case and seals better than one that is just pushed in — it must be screwed in before the watch goes in water. Gaskets age, so water resistance should be checked at a service (every couple of years if the watch is often in water). The item's own water resistance is listed under specifications; see also water resistance and dive watches.

If you have a question about a particular watch, ask Nord, our assistant, at the bottom right — or write to us.

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