If you ever wear watches or ever setup to in the future, you might be curious as to what ATM stand for. ATM is a detail included in the specs for many watches, but there are a surprising variety of people who don’t recognize what ATM definition is.

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ATM method atmospheres

Simply put, ATM is one abbreviation of the word atmospheres, and also it is used to price water resistance in a timepiece. Together you space probably mindful of, there are different types of watches created different species of environments, so the a watch the is okay to wear while in the shower head is not necessarily walk to survive your next snorkeling pilgrimage in Hawaii.

The different water resistance capabilities of assorted watches is why the worldwide Organisation because that Standardization set up a global rating system for ATM (thanks guys!). Learning the various ratings and also their depth is quite important, especially if you want to stop your clock from ending up being a beautiful paperweight.

ATM Ratings

The various ATM ratings have the right to be misleading. The most usual ratings room as follows:

When most people read this, they think "Great. 3 ATM, so I can dive 30 meters with my watch." Sorry yet no.


Waterproof clock - I can do anything

Here"s where most people go wrong. They carry out a quick search, see that your watch is waterproof approximately 30-200 meters, go scuba diving and—goodbye beautiful timepiece.

What they don"t understand is that when the actual experimentation of the watch is conducted to identify the rating, the tests space performed in 100% tho water, through zero activity. This does no emulate the kind of environment that a watch will be supplied in when under water, and unfortunately, the slightest movement deserve to lead to press overload and permit liquid come seep into the watch.

To identify the rating, manufacturers usage two form of procedures. One is dry testing: a test that offers varying level of air press to expose any type of air leaks. This is the an initial step and also if any type of leak exists, the watch won"t it is in waterproof.

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The 2nd test to identify if a watch is certainly waterproof is wet testing. Through wet testing, the timepiece is inserted inside a small chamber the is fifty percent filled v water and fifty percent filled v air. Rely in the air-filled side, the clock is then progressively immersed in water and also the air press inside the room is progressively decreased. If any type of bubbles space released from the clock under water, the test result is the the watch is no waterproof. If the watch does not release any type of air bubbles, climate fantastic! however remember this test is still in a water chamber v no activity.

Waterproof watches in actual Life Uses


Clearly, it can be a bit perplexing to determine what atmospheres you can expose her watch to based upon the ahead paragraph. Your activities are no linear—you relocate all the time, and also so walk water. Because of that, the is perhaps much more helpful to think about real-life instances that correlate to the ATM ratings: