The term “5 ATM” in the context of water resistance refers to the level of pressure a watch can withstand when submerged in water. ATM stands for “atmosphere,” and each ATM represents the equivalent of atmospheric pressure at sea level.
A watch with a 5 ATM water resistance rating is generally suitable for everyday use and can handle light water exposure without damage. However, it is not suitable for swimming, diving, or any water-related activities that involve significant water pressure or prolonged submersion. If you plan to use a watch for water sports or diving, you should look for a timepiece with a higher water resistance rating, typically indicated in meters or atmospheres.