“This watch is water resistant up to 30 meters.” Anyone with experience of buying a watch has probably contemplated putting this statement to the test. Our advice? Don’t!

Tag Heuer Formula 1 watch that should be water resistant up to 200m. This Tag Heuer has extensive water damage which can be seen by the damage to the dial and hands.

In fact, “Water resistant” might rank as one of the watch industries’ greatest myths. The question remains then, why do watches tell us that they are water resistant at all and what does it actually mean?

If a watch is designated as water resistant, it is humidity-protected and can endure splashes of water, perhaps from the rain or washing your hands. However, it is far less prepared for a trip alongside you in the shower, swimming pool and most certainly not the open ocean.

Today, standards for water resistance are provided by the International Organisation for Standardisation (ISO). One such standard – ISO 6425 – refers specifically to dive watches which you can read more about here, but we’ll instead focus on ISO 22810, the standard for everything else including popular fashion brands such as Gucci, Armani, Tissot and more. It specifies the test methods used to verify the water resistance of watches and moreover, indicates the marking which the manufacturer is authorised to apply to them.

A Tag Heuer automatic watch. This case back indicates a water resistance of 200m

However, manufacturers are provided with a great deal of discretion when it comes to water resistance testing methods, free to use air chambers rather than genuine water submission and only required to do so for a minimum of 10 minutes. it is also worth noting that watches are generally tested at their highest level of performance, when they are still brand new and boast perfect gaskets and seals.

The reality watch wearers face is likely to be vastly different from the perfect lab-like conditions so, regardless of your watch’s rugged exterior, the majority are simply not designed to tackle water and it would always be advisable to exercise caution.

But what about those specific meter references? Surely they stand for something?

Contrary to popular belief, the specific metre references (such as ‘3 BAR / 3 ATM / 30m / 100ft) do not actually indicate the depth of water that watches are able to withstand and should not be taken literally. Instead, the depth warning refers to the amount of accidental splashes that watches can take, signifying the results of static pressure tests conducted under laboratory conditions.

Realistically, the bigger the resistance the more likely a watch would be to withstand greater oeriods of time submerged in water as well as higher levels of pressure. For example, your 100m water resistant watch could probably tackle water sports activities and swimming whereas your 30m resistant watch should not be forced to withstand more than a few accidental splashes.

In principle though, your 30m water resistant watch could even succeed during swims beyond depths of 30 metres. However, the varying success of watches under water relies on a large number of factors including lab-like conditions, short immersion periods and recently tightened gaskets and seals and while your nearby leisure centre might provide something close to the ideal environment, the open ocean most certainly doesn’t. No matter how impenetrable you think your watch is, water remains its kryptonite, its number one enemy and not something to be toyed with.

Don’t be alarmed though – it is not all doom and gloom. There are many steps you can take to make sure your watch is in the best possible state to challenge the watery foes and one of the first things you can do is ensure annual water resistance checks.

At Fix My Watch, we are adept at taking your watch through the rigours of water testing, ensuring that all gaskets and seals are water resistant as well as replacing and lubricating ones that have worn out.

A Longines watch being pressure tested in our workshop at Fix My Watch to ensure all gaskets and seals are working correctly in order to reinstate the water resistance of the watch.

Of course, everyone’s lifestyle is different and if you are someone who likes to wear your watch while surfing or swimming it is advisable to have your watch checked more regularly throughout the year.

Meanwhile, if you have chosen to wear your watch while swimming in diving in seawater, we would advise rinsing it in fresh water and drying it thoroughly. This helps to prevent a buildup of corrosive salt.

If you’d like to chat to us further about any other issues with your watches, make sure to check out our other blog pieces or get in touch via our contact page here.