Divers Don't Breathe Oxygen, Wear Flippers or Goggles

A Labeled Enriched Air Nitrox Cylinder

When I first got scuba certified, I was a little put off by the instructors always correcting my terminology. "It is called a mask not goggles" he would say or "it is an air tank, not an oxygen tank" she might tell me or "fins are for people, flippers are for dolphins." Why be so picky? It wasn't until I became a dive professional that I understood why these seemingly minor issues are important for safety of the diver and others. 

Take the googles issue for example. The reason we must refer to it as a mask and not goggles is one of safety. Swim googles are often worn while swimming, but only a scuba mask is suitable for diving to depths beyond a swimming pool. A scuba mask covers both the the eyes and nose, which allows the diver to equalize the air space in the mask to ambient pressure. If a diver were to dive with swim goggles s/he could do some serious damage to his/her eyes as the pressure increases to 2-5 times the pressure experienced at the surface. If the googles were to flood with water it could lead to panic situation and possibly a fatality because there is no way to clear the water from goggles. It must be be made clear to a beginning diver that goggles and dive masks are different, and goggles can never be substituted for a proper mask.

As for calling your dive cylinder an "oxygen tank", this is to prevent another potentially fatal mistake among new recreational divers. You see, recreational divers often do have oxygen cylinders around for emergency first aid use since the primary first aid treatment for injured divers is 100% oxygen. Technical divers sometimes use 100% oxygen as a decompression gas. The problem is that 100% oxygen has a maximum operating depth of just 20 feet. So if a recreational diver, new to the sport were to go diving with an "oxygen tank" and exceed 20 feet of depth that person could succumb to oxygen toxicity, suffer convulsions, and drown. For this reason it is important to call the cylinder an air cylinder which it usually is. One might also call it a breathing gas cylinder if diving an enriched air nitrox mix (air enriched with additional oxygen). By using proper terminology, the rare possibility of a fatal mistake is minimized.

As for fins vs. flippers, that one is just semantics, but I still prefer fins to flippers.

Can you think of other scuba terms that people get bent out of shape about? Share in the comments.

Shallow Dives Are NOT Safer

Ascend slowly from every dive, especially the last 15 feet.

Recently, I have heard a few folks make comments like, "The water isn't that deep, so the diver will be fine" or maybe you have heard a diver say, "It is only a swimming pool, what could happen?"

These comments are frightening because they show a serious misunderstanding of the most basic concept of scuba diving safety. This is a failure of the diver the understand the risks in diving!

Let's go back to your beginning scuba course. Recall it starts with a lesson on Boyle's Law and lung over-expansion injuries. You must learn and prove mastery of this concept with a quiz before you can ever get into a pool. Often the analogy of a balloon popping as air expands on ascent is used to explain what happens inside the lungs if you hold your breath or if mucous or lung tissue traps air in the lung while ascending. Unfortunately delicate lung tissue is not as strong as a balloon and alveoli can be torn in as little as 3 feet of water. Rupture of lung tissue can allow air to enter the blood stream, which is potentially fatal! The greatest changes in volume occur at the top of the water column in the few feet near the surface so this is where most lung over expansion injuries actually occur. You are told to never hold your breath, never dive with a cold or congested lungs, and always ascend slowly from every dive, but there is always some risk of lung over-expansion. Shallow water in no way lowers the risk. Shallow water such as a pool does lower the risk of decompression sickness, which is why some divers mistakenly think shallow water is safer. It simply is not. I have seen many new divers, dutifully complete their safety stop and then bolt from 15 feet to the surface. This is a risk both for decompression sickness and gas embolism!

Over time some divers get complacent and forget this basic information. Don't let this happen to you. Continue your education. Keep learning beyond the basic scuba course, which is meant to inform you, but not overwhelm you. Be an active Divers Alert Network member and read the great dive safety information the organization provides. Learn beyond the basics. Seek out books on diving. Entry level courses are entry level. There is much more to learn. Treat every dive seriously, regardless of the depth. Ascend slowly from every dive, especially the last 15 feet. Breathe continuously and don't dive if you have congested lungs.

Transform Yourself- Transform Your Ocean!