Scuba divers spend a lot of time at the surface. In fact, if you surface swim from the shore, you may spend as much time at the surface as you do underwater. However, there's still life to see at the surface, and snorkels allow you to enjoy it without wasting your air supply.

You should always carry a snorkel, even if you don't plan on a significant surface swim. For example, if you drift far from the boat or entry point during your dive, a long swim may be necessary. With a snorkel, you can alternate your swim between face-down and face-up positions, which is often desirable when muscles become sore.

Snorkels are mounted to your mask strap on your left side. This prevents interference with your regulator, which comes from your right side.