Why are full face snorkels not allowed?
Why are full face snorkels not allowed? CO2 can build up with these devices and put you in a very dangerous situation. There have been deaths, and many near death experiences. Can you breathe underwater with a full face snorkel mask? No, you can't breathe underwater with any snorkel.
What happens if snorkel goes underwater?
Unlike scuba diving where you have your own air supply, snorkels don't let you breathe while you are fully submerged in the water. The breathing tube can fill up if it dips below the water's surface, for example, a wave splashing over you, or if you dive underwater to get a closer look at marine life.
When should you not snorkel?
Choppy waters are not ideal for snorkeling, especially; if you're not a proficient swimmer. Wavy waters will bounce you around, and you'll experience diminished underwater visibility because of increased moving debris and sand. Waves also influence the ease and safety of getting in and out of the waters.