Gem Mythbuster: Waterproof Watches and Other Watch Myths

This week's Gem Mythbuster addresses several myths concerning watches.

Myth #1:  Waterproof watches

•  They don't exist.  Watches can be water resistant but no watch is waterproof.  According to guidelines issued by the Federal Trade Commission, since the 1960's, watch marketers are not allowed to label their watches "water-proof".  Even watches designed for deep-sea diving cannot claim to be waterproof.
• There are levels of water resistance - watches can be water resistant up to various depth ratings:  50, 100, 300 or 500 meters, etc.  Watches that are marked "water resistant", but do not specify a depth rating are not designed to be submerged below the surface of the water.
• If you want a watch that is water resistant enough to be able to submerge it below the surface of the water, you should also choose one designed with a screw-down crown and a screw-in caseback.
• The seals that keep water out can wear out over time.  A watch is water resistant as long as the rubber gaskets in the case, crown and are routinely replaced.

 Myth #2:  Overwinding a watch

• You can't overwind a watch.  All modern automatic watches are equipped with a slipping clutch mechanism which prevents overwinding of the watch.

Myth #3:  Leaving the stem pulled out extends the life of the battery.

• You should never leave the stem of a watch pulled out.  This exposes the movement to dust and moisture that can cause damage.