During a dive in open water, you should always wear gloves. Thereby those serve as protection against cold in cold bodies of water. But also in warm bodies of water you need them to protect your hands. Hence poisonous cnidarians (e.g. jellyfish) or sharp objects under water (for instance when wreck diving) cannot harm you.
What gloves should I wear when diving?
There are different models, which are appropriate for the different types of diving.
If you want to remain as mobile as possible under water, you should wear thin ones made of neoprene. These cover 5 fingers as a rule.
Cold protection gloves are made of thicker neoprene and usually have only 3 fingers. The thumb and the index are left free for the hand signals.
As a rule the material should be as thick as your diving suit.
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