A watch’s water resistance may be a bit deceiving. For instance, if a watch is said to simply be water resistant with no specified unit, it’s very likely that the watch is not actually resistant to submersion in water, but merely resistant to rain, sweat, and other minimal splashes.
So what, exactly, does water resistance mean for a watch?
Water resistance, a basic definition
According to the International Organization for Standardization, or ISO, water resistance, most basically, refers to a watch’s ability to resist water from entering its case.
Essentially, a watch’s water resistance is determined by how well the watch case is sealed. This means that a watch’s water resistance does not remain constant, and may require maintenance every couple years to ensure accurate water resistance.
Additionally, and perhaps more confusedly, water resistance does not refer explicitly to the depth a watch can safely go. In fact, water resistance, measured in various units including bar, atmospheres, or meters, is determined by the amount of pressure a watch can withstand, not the depth it can withstand.
Water resistance guidelines
The following provides a basic set of water resistance guidelines.
- No unit: Will resist rain, sweat, and minimal splashing. No submersion.
- 30m: Will resist moisture and submersion. No swimming.
- 50m: Will resist moisture and shallow swimming.
- 100m: Will resist submersion during most recreational water sports. No scuba diving.
- 200m: Will resist submersion during recreational scuba diving and other water sports.
- 1000m: Will resist submersion during deep sea and other professional diving.
But as mentioned, water resistance depends upon a watch’s seals. If seals have become weakened or damaged after years of wear, they will not be able to resist water from entering the case and thereby damaging the watch. Be sure to check your watch’s gaskets and/or rubber rings around the crown, crystal, and case back to ensure it’s well sealed and prepared for the water.
How water resistant is your watch and what water sports do you participate in while wearing it? Tell us below!