What Is Water Resistance and How Much Do You Really Need?
What Does Water Resistance Actually Mean?
When a watch says it is water resistant, it does not mean it is waterproof. Water resistance is a rating that tells you how much water pressure the watch can handle — and the numbers can be confusing.
At Funny Items, every automatic watch we build is tested for water resistance before shipping. Here is what the ratings mean and how to pick the right level for your lifestyle.
Water Resistance Ratings Explained
| Rating | What It Means | Can You Swim? | Best For |
|---|---|---|---|
| 30m / 3ATM | Splash resistant | No | Rain, hand washing |
| 50m / 5ATM | Light swimming | Shallow only | Shower, poolside |
| 100m / 10ATM | Swimming and snorkeling | Yes | Swimming, water sports |
| 200m / 20ATM | Recreational diving | Yes | Scuba diving, deep swimming |
| 300m+ | Professional diving | Yes | Saturation diving |
The Truth About Water Resistance Numbers
The meters (m) or ATM rating is measured in a lab under static pressure. Real-world conditions are different:
- 30m does NOT mean you can dive to 30 meters. It means the watch can handle light splashes.
- 50m is fine for rain and hand washing, but not for swimming laps.
- 100m is the minimum for swimming. Most Funny Items dive watches are rated to 100m+.
- 200m is ideal for recreational diving and all water sports.
How Water Gets Into Your Watch
Water enters through three main points:
- Crown — The most common entry point. Always screw down the crown before water exposure.
- Case back — Sealed with a gasket. Damaged gaskets let water in.
- Crystal — Sealed with a gasket. A cracked crystal compromises water resistance.
How to Maintain Water Resistance
- Screw down the crown before any water contact
- Check gaskets每年一次 — gaskets dry out and crack over time
- Pressure test every 2-3 years at a watchmaker
- Rinse with fresh water after salt water exposure
- Do not operate the crown underwater
Funny Items Water Resistance
Our dive watches and GMT watches are built with screw-down crowns and tested for water resistance. The 43.5mm Relax Automatic Watch and Pepsi NH34 GMT are suitable for swimming and snorkeling.
Our dress watches and vintage bronze watches have water resistance suitable for daily wear and light splashes, but are not intended for swimming.
Frequently Asked Questions
Can I shower with my watch?
Only if rated 50m+. Hot water and soap can damage gaskets even on water-resistant watches. It is best to remove your watch before showering.
Does water resistance decrease over time?
Yes. Gaskets degrade, seals wear out. Have your watch pressure-tested every 2-3 years.
What if my watch fogs up?
Take it to a watchmaker immediately. Fog means moisture has entered the case.
Related Articles
- NH35 vs NH34 Movement Guide — Movement specs for your build
- What Is a Sapphire Crystal? — Crystal types and water resistance
- 5 Watch Strap Styles — Best straps for water activities