Below is a table that will show us the different water resistance ratings and the activities that they are suitable for and this will help you select the correct scuba watch for you.
|Water resistance rating||Suitability||Remarks|
|Water Resistant 30 m or 50 m||Suitable for water related work, recreational swimming and fishing.||NOT suitable for diving.|
|Water Resistant 100 m||Suitable for recreational surfing, snorkelling, sailing and water sports.||NOT suitable for diving.|
|Water Resistant 200 m||Suitable for professional marine activity and serious surface water sports.||NOT suitable for diving.|
|Diver's 100 m||Minimum ISO standard (ISO 6425) for scuba diving at depths NOT requiring helium gas.||Diver's 100 m and 150 m watches are generally old(er) watches.|
|Diver's 200 m or 300 m||Suitable for scuba diving at depths NOT requiring helium gas.||Typical ratings for contemporary diver's watches.|
|Diver's 300+ m helium safe||Suitable for saturation diving (helium enriched environment).||Watches designed for helium mixed-gas diving will have additional markings to point this out.|
Note: The depth specified on the watch dial or case represents the results of tests done in the lab, not in the ocean.