What is the water resistance of a watch?
If a watch is water resistant, you will usually see WATER RESISTANT on the case back, some watches will show it on the dial as well. But if a watch has no water resistant, then you’d better keep your watch away from water.
There are 3ATM, 5ATM, 10 ATM, 20ATM and 30ATM water resistance, sometimes measure it with BAR.
Let’s see what is ATM and BAR.
Every 10 meters of underwater depth increases the pressure by 1 bar, and when the pressure inside and outside of the case is uneven, the watch is prone to bursting.
Therefore, watch manufacturers use the “pressure value” to test the water resistance of a watch, and use the pressure resistance value (unit BAR or ATM) to express the depth of water resistance.
1 atmosphere is equal to 10 meters of water depth, 1 ATM = 1.01325 BAR, which can be estimated as 1BAR = 1 ATM = 10 meters of water depth.
What does 10 ATM means?
So 10 ATM means 100 meters water depth.
This 100 meters does not mean the depth your watch can dive, but the pressure of 100 meters water depth when water surface is rested.
100 meters is equal to 10ATM/BAR, usually the water is about 20 liters per minute when you take shower, which means that it will not higher than 10ATM water pressure, so you can take shower with a 10ATM water resistant watch.
However the hot water will affect the sealing of the rubber ring and causing in water vapor. You are not suggested to take hot water shower with any watches.
What you can do when wearing a 10 ATM water resistant watch?
Simply 10 atm water resistant watch is safe for swimming, but not diving. Your arms are always swiping when swimming, so it is different from static water pressure.
3 ATM water resistant watch is called “everyday life waterproof”, obviously it can only resist the washing and raining.
Only watch with water resistant over 100 meters can be worn to swim. A 300 meter water resistant watch can be called a diving watch.
Here is the chart of the watch water resistant
What to do if a watch is water damaged?
Here are some options if your watch is not water damaged badly.
- Put your watch into a closed container together with silica gel (a small pack desiccant). Take out the watch few hours later, and you will find the water is removed. This method is easy and no harm to your watch.
- If there is moisture inside, you can wrap the watch tightly with several layers of toilet paper or moisture-absorbing flannel and bake it at a distance of 15 cm from a 40-watt light bulb for about 30 minutes to remove the moisture.
- Left the timepiece out to dry. One way to do so is to place the watch case back side down on a radiator, a lamp, or in a sunny spot on a window sill. This will draw the moisture away from the movement and heat the watch up a little bit so that the water dries faster.
But unfortunately, what if the damage is severe? Well, the answer is pretty obvious — bring the watch to a professional watchmaker or repair store. Thy know exactly how to take a watch apart and dry just about every component in sight.
Things you need to know about the water resistant watch:
- Do not wear any watch to take sauna!
- Dry the watch off after it getting any water
- Do not pull out the crown when there is water on watch
- Water resistance is not a lifetime feature, so you should maintain it regularly.
If a watch can be waterproof, the small rubber ring（O ring) in the case back is key component. So the problem is: Rubber will age.
When the watch is routinely maintained every four to five years, the waterproof rubber ring must be replaced. If it is not an official maintenance organization, you may not be able to get the original rubber ring.
