by Natalie Novak Perez (August 2013)
Well, I do not know you personally, but I have never met a person who can breathe water, though I would love to. Assuming that you, like me, cannot breathe water, if you go underwater, this needs to taken into account whenever you do.
If you are scuba diving, you need to remember three things at all times. These are very important, but not very difficult questions. If ever you feel nervous underwater, and you are not sure if you are OK, ask yourself these three air-related questions. If you do not know the answers to these three questions, you are not safe, and thus you are not OK. And you were right to be nervous!
Question 1: Am I breathing?
When people start thinking, they often stop breathing. When I am driving my car and looking for an address, I feel a need to turn the radio down, and I often find myself holding my breath as I search. The music from the radio does not block my vision, but it disturbs my concentration. When I want to concentrate, I want to stop multitasking. That is a normal response.
Underwater, because we can not breathe water, the human default setting is to hold our breath. Breathing continuously while scuba diving is an unnatural learned ability to multitask. It can be interrupted, especially when we are concentrating on something else. When you ask yourself if you are breathing, you will bring your concentration back to your breathing.
At all times you should either be inhaling or exhaling, with no pause in between. If you are doing this, and thus not holding your breath, then your airway is open. That means that if you do not notice that you are going up, the expanding air in your lungs will be able to escape. Continuously breathing is how you stay safe when breathing compressed air underwater.
Question 2: How much air do I have?
All the time you are underwater, you should know roughly how much air you have in your tank. This is because responsible divers checks their air often. Experienced divers (if they are in the habit of checking their air often) get a feel for how quickly they go through their air at different depths. Suddenly going through more air then normal in few minutes is a sign that either you are breathing harder or you gear has a leak.
Of course, there is a much more important reason to check your gauge often. Your gauge is the tool you use to avoid running out of air to breathe underwater.
Before you enter the water to make a dive, you should make a dive plan. In my opinion, the most important part of this plan is to decide upon the tank pressure/amount of air that will be your reserve. You are reserving this air to get you and your buddy slowly and safely to the surface. If you or your buddy reach the reserve, it is time to end the dive and start your slow ascent.
It is not safe to end your dives with an empty, or almost empty, tank. Your goal should be to have at least 50 bar/500 psi left in your tank after a dive. This air was not for you, it was for you to give to your buddy if they ran out of air or had a problem with their gear.Your buddy should have the same goal, and surface with a reserve of air left over in their tank. This air was reserved for you.
Question 3: Where would I get air if I did not have any?
The most common answers are my dive buddy and the surface. To avoid the need to make any kind of emergency ascent, stay close to your dive buddy. In order to stay safe underwater, you should maintain a maximum distance one breath away from your dive buddy at all times.
In order to avoid the need to make an emergency ascent due to a broken alternative air source, you and your buddy should show each other that your alternative air sources work before your dive. When you do this, you are also showing each other which kind of alternative air source you will use for the dive.You need to know how your buddy would give you an alternative air source in an emergency. Whether they would give you an octopus/another second stage to breathe from, an independent, and often small, separate tank of air with a regulator to breathe from, or if they would give you the second stage from their mouth, and switch to breathing from something else, is important to know.
You need to know how your dive buddy's gear works before you enter the water, so that you do not have to figure it out in an emergency. Your buddy is your most important piece of diving equipment. In an out-of-air emergency, it is they and their gear that will provide you with air.
So, if you ever look up to the surface and feel that it is so far away, and start to get nervous, ask yourself these three questions. It only takes a few seconds but, when you know the answers, you will be safer and thus feel more confident breathing air underwater.
Turtles can hold their breath underwater but SCUBA divers should not.