Waterproofing of watches depends on the waterproofing apron of the mirror, back cover and handle to reach the corresponding standards. All waterproofing meters are marked "WATER RESISTANT" or "WATER PROOF" on the bottom cover. Watches without waterproof markings are only dust-proof and should be free of water. Thirty meters (3ATM, three atmospheric pressures) waterproof meter can be used in daily combing or rain, that is, water droplets only splash on the surface without any water pressure added to the meter.
When choosing waterproof watches, we should pay attention to the text instructions about the scope of application, keep calm in the face of the propaganda of numerical values and pictures, and buy them as needed; wear waterproof watches within the scope and circumstances indicated in the instructions; do not wear waterproof watches in bathing, bathing, hot springs, exposure to high temperature vapor, sudden changes in temperature and other environments; and wear waterproof watches when wearing waterproof watches. It is necessary to clean watches, make waterproofing tests and replace waterproofing parts in the correct time at the designated or regular maintenance points with the required technical ability and equipment level. Regular cleaning and maintenance of expensive watches is more important.
At present, any waterproof watch, no matter how many meters it is marked, can not be used in hot water (40C degree). There are two reasons: 1. The permeability of water molecules is greatly enhanced when the temperature rises, and all waterproof watches are designed based on cold water. 2. According to the thermal expansion and contraction, some components of the watch will expand in different degrees under hot water conditions, which will lead to the possible gap enlargement.