Swimming with a waterproof watch chooses a 100M waterproof watch, which is safer. Although an ordinary 30M waterproof watch can withstand 3 atmospheres, the premise of its detection is laboratory conditions, that is, the temperature is 20-25 C°, and the water and the watch are still. When swimming, the watch and the water are in relative motion, and there is a certain impact force. The pressure between the water and the watch is often much greater than 3 atmospheres. Therefore, the watch is prone to water ingress.

Waterproof watches cannot take hot baths and saunas. The difference between the temperature in these two cases and the waterproof test temperature is too large. In addition, according to the principle of thermal expansion and contraction, each component of the watch is different in material, shape and size. When the temperature changes greatly, the amount of expansion and contraction deformation Different, it is easy to produce tiny gaps, causing water to enter the watch. Occasionally no water enters, indicating that the watch has good waterproof performance, but in the long run, it will accelerate the aging of the waterproof parts of the watch and affect the normal service life of the watch.

The watch that has entered the water is still waterproof when it is tested on the waterproof machine. This situation is caused by improper use. The accumulation of cold and heat (such as exposure to the sun or an air-conditioned room with low temperature) causes the waterproof parts of the watch to deform instantly, and the water vapor Enter, when the environment is normal, the waterproof parts return to normal, and still have the waterproof function.