How Scuba Diving Works
A tank, a jacket, and pressure that changes every few metres. This is what we explain on the beach before a first dive in Havelock.
What you are dealing with
Scuba is compressed air, a BCD (the inflatable jacket), and water pressure. We brief all three before anyone puts a regulator in at Continental Scuba.
Breathing from the tank
The cylinder is just a supply. You breathe in through the regulator and out into the water, slow and even. First-timers often empty a tank fast because they are tense. Once the breathing settles, the dive gets quieter and you stay down longer.
Pressure and depth
Salt water adds about one atmosphere of pressure every 10 metres. At 10 m you are at twice surface pressure, so the air in your BCD and your ears takes up less space. That is why the jacket feels different on the way down, and why you equalise as you descend.
Try Scuba stays shallow on purpose. On Open Water we teach you to watch depth and time on the computer instead of racing the number.
Staying off the bottom
Your lungs, the BCD, the wetsuit, and the lead on the belt all pull against each other. A slightly fuller breath lifts you. A slower exhale lets you sink a little. People who look “still” in the water are making small changes, not gripping the reef.
The practical version is in the water: Try Scuba for a first go, or SSI Open Water if you want to learn the skills properly.
We always brief. First dives are with an instructor. Depth is a limit, not a contest.