Naturally Nitrox

By Geri Murphy

Have you heard of nitrox but never tried it? Are you curious, but never seem to have the time to take a nitrox diving certification course? If so, youre one of hundreds of thousands of divers who have yet to sample the joys of this new type of diving.

A recent poll of 651 Skin Diver readers indicates that only 10 percent of the diving population has been nitrox certified. That means that 90 percent has not had the opportunity to participate in this type of training. Most interesting is that the poll indicated 71 percent wants to know more.

Now here is an idea you may not have thought of. How about taking a nice, easy nitrox certification class while you are on a diving vacation? It would be convenient, safe and fun;all at the same time. You can enjoy a tropical diving vacation while enriching your diving knowledge about this new rage in diving.

Recognizing this new trend toward nitrox training and diving, Bob Sotos Diving, Ltd., in Grand Cayman has come up with an irresistible training program! The course is short, simple, yet totally safe. Certified scuba divers upgrade their knowledge while enjoying all the pleasures of warm tropical seas, white sand beaches and great diving.

In addition to operating a fleet of dive boats that make daily excursions to nearby reefs, walls and wrecks, Bob Sotos operates a large dive training center at the Treasure Island Resort. It is a fully certified PADI Five Star training facility with an air-conditioned classroom, adjacent training pool, shore dive facility and dive boats that go out twice daily. Under the guidance of Training Director Pip Wyn-Evans, Bob Sotos offers scuba classes starting on a daily basis and at almost any hour of the day. There is no waiting;they make scuba training a pleasure.

The same philosophy of instant customer service is now being applied to their nitrox training program. You can enroll in a class any day of the week. It consists of two to three hours of classroom or poolside lecture, followed by a two tank open water dive from a boat or the shore. Most people start their classroom session in the afternoon and make their two tank dive the next morning. If you are in a real hurry, you could take the class in the morning and make the dive in the afternoon. Its that simple.

The course content is just as simple as the sign-up and course hours. Bob Sotos instructors have a nice way of cutting through the super technical theory and abstract mathematics of nitrox for recreational divers. Here are just a few things you are likely to learn.

What is Nitrox Diving? Nitrox is divings way of improving upon nature. You start with natural air, filter it, compress it and add a dab of oxygen. Voila! You have nitrox, otherwise known as enriched air.

It is called enriched air because you have taken normal compressed air and enriched it with oxygen. Normal air is 21 percent oxygen and 79 percent nitrogen. The enriched air mix used for Bob Sotos Diving Nitrox Course is 32 percent oxygen and 68 percent nitrogen. This change in gas mixtures has certain benefits, which we will talk about later.

Is Nitrox Diving New? It may be new to recreational diving, but nitrox diving has been around for more than 50 years. It has been a favorite choice of breathing gas for military, scientific and commercial divers because it offers extended bottom time for working purposes.

Is Nitrox Diving Safe? Yes. Nitrox has been time-proven over five decades and is a fully certified breathing mixture for government employees and military groups worldwide. Furthermore, nitrox (or enriched air) has been adopted and offered for recreational dive training by most of the nationally known training/ certification agencies such as PADI, NAUI, SSI, NASDS, IANTD, ANDI, TDI and many others.

What is the Depth Range for Nitrox? Nitrox is primarily a shallow to medium depth breathing mix, designed for people who work underwater. With the 32 percent oxygen mix Bob Sotos Diving utilizes, you have the same diving depth range as normal air;surface to 130 feet. Nitrox mixtures richer in oxygen are restricted to shallow depths.

What is Nitrox Like? Nitrox smells, tastes and looks the same as compressed air. You cannot tell the difference by breathing it. That is why nitrox/enriched air tanks are clearly marked and color coded with bands of yellow and green.

Why Use Nitrox? Breathing nitrox allows you to extend your bottom time beyond the normal no decompression limits of compressed air. Also, many divers claim breathing nitrox makes them feel better, because the extra oxygen and the reduced nitrogen help avoid that feeling of fatigue after the dive. The instructors at Bob Sotos call it fatigue free diving.

You can also make your diving extra safe by breathing nitrox, but using the air no decompression tables or an air computer. This gives you a safety edge. It is perfect for those divers who are a little bit older, a little bit wiser or a little bit out of shape.

Do You Need Special Equipment? Except for your tank, no. You can use your personal regulator; Bob Sotos supplies the special tanks. Although several equipment manufacturers produce special nitrox regulators for richer oxygen mixtures, these devices are not required for the standard 32 percent oxygen mix used in the Bob Sotos course.

On the other hand, the scuba tanks are indeed special. They have been very carefully cleaned of any oil residue or contaminants that could react with the higher mixture of oxygen. Nitrox tanks are always clearly marked with enriched air decals as well as tags that indicate the gas mixture and the date of the last inspection.

How Do You Know What is in the Tank? As part of the training course you learn it is standard procedure for every diver to personally check the enriched air mixture in his/her tank prior to diving. This safeguard eliminates the possibility of human error at the filling station. Students learn how to use a small, hand-held oxygen analyzer that tells exactly what percentage of oxygen is in the tank. You simply open the tank valve slightly and place the analyzer sensor in the stream of flowing air. If the analyzer reads 21 percent, your tank is filled with normal compressed air. If it reads higher than 32 percent, you find another tank. This is done at the Bob Sotos Dive Centre, just prior to loading the tanks on the boat.

Why Do You Need to Take a Class? While nitrox diving is easy and very safe, there are a few basic rules and procedures that require training. You learn most of these during a classroom or poolside session. Some of the time is devoted to learning how to use the nitrox no decompression tables for planning a dive. Some of the time is spent learning how to calculate the nitrox equivalent of a normal compressed air dive and there is a brief discussion about oxygen partial pressures. The informal class training is designed to keep you safe. Then, you make the dives and practice the procedures you have been taught. And, while you are doing it, you get to enjoy lush coral reefs, a multitude of fish life and fascinating shipwrecks. Life doesnt get much better than this.

What Does a Nitrox Class Cost? It depends on what you want. Bob Sotos offers two versions of the nitrox training program. You can take the class and make a two tank boat dive on nitrox for $199. On the other hand, if you are on a tight budget, you can take the same class and make a two tank shore dive for only $145. Either way, you come out of the class as a certified nitrox diver in less than two days, enjoying your vacation while training and diving.


Bob Sotos offers a wide variety of attractively priced dive packages with numerous hotels and vacation condos. Packages can be customized to your specific desires and needs. Design your own dive vacation by contacting Bob Sotos Diving, Ltd., at (888) 718-7400 (toll free), (345) 949-2022, fax (345) 949-8731 or e-mail bobsotos@candw.