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Engaging in SCUBA diving is safer than it has ever been in the history of the sport. Practically all of the training received as a SCUBA diver centers around surviving in the aqautic world. The certifications listed here represent my effort to safely participate in SCUBA diving.

This certification declares that the diver has exhibited competence in diving safely while utilizing breathing gas which includes helium, at depths which far exceed Recreational Diver limitations. Further, the diver has exhibited competence in utilizing staged decompression procedures to off-gas inspired nitrogen. This certification is known as the ultimate certification in civilian SCUBA diving.

The use of Trimix prevents a diver from being subject to the "Rapture of the Deep" which plagues all air-breathing divers at depths of 100'+. Deeper wrecks, reefs, and caves are accessible and much more safely experienced by breathing Trimix. Although this sounds wonderful, the helium in Trimix has its own dark qualities which must be dealt with. Water pressures increase with depth and one of the diving physiology issues of deeper diving is for the human body to safely release the compressed breathing gas micro-bubbles which collect in the body tissues. Oxygen in Trimix is not really an issue, since it is metabolized. The nitrogen and helium in Trimix, however, is not metabolized and must be "off-gassed" safely. This is done by a series of staged decompression stops during the ascent. One problem is that helium off-gasses much differently than nitrogen.

The comparison of nitrogen micro-bubbles and helium micro-bubbles in the body tissues can be compared as follows. If an apple and a tennis ball are held 24" beneath the water and released slowly, the apple will float to the surface slowly while the tennis ball will almost breach in its rush to surface. Likewise, nitrogen exits the body slowly while helium rushes to escape body tissues. Accordingly, Trimix requires deeper decompression stops and usually the stops are of longer duration. Trimix may be considered a trade-off, as the diminished Rapture of the Deep is offset by and increased risk of decompression sickness during the ascent of a deep dive. Nonetheless, Trimix is one of the best things to happen to diving.
This certification declares that the diver has exhibited competence in diving safely in overhead environments, especially underwater caves. This is one of the most coveted of all diving certifications. It is a known fact that Cave Divers created the majority of technical diving practices in use across the world.

Cave Diving is a form of exploration that is enjoyed by thousands of divers worldwide. There are two incredible statistics related to Cave Diving. First, the percentage of Cave Divers in the total diver population is extremely low. Second, the percentage of diver injuries among Cave Divers is much lower than among the rest of the Recreational Diver population. This is most likely due to the extreme amount of training that Cave Divers must receive prior to certification and also the extreme vigilence that Cave Divers exhibit when they dive in their environment. Unfortunately, when a Cave Diver is injured or dies, society seems to over-react and stereotype Cave Divers as reckless individuals with death-wishes. Statistics reveal that just the opposite is true.

This certification declares that the diver has exhibited competence in diving safely to a depth not to exceed 180' while breathing air. Further, the diver has exhibited competence in utilizing staged decompression procedures to off-gas inspired nitrogen. This certification is known as the ultimate certification for divers breathing air while deep diving.

As is seen in the photograph, the decompression process is enhanced by using oxygen-rich breathing gas while ascending. In this particular dive, a mixture of 50% oxygen was used from a depth of 70' to 20'. Then, pure oxygen was breathed from 20' to the surface. Thus, the decompression process was diminished by almost an hour.
This certification declares that the diver has exhibited competence in diving safely while utilizing breathing gas enriched with levels of oxygen which range from 50%-100%. Further, the diver has exhibited competence in utilizing oxygen-enriched breathing gas to off-gas inspired nitrogen. The chart below gives an example of a 30 mins dive to 120' on air.
Action Depth Duration Run Time Gas Rate Descent/Ascent
Descend to 120' 2 mins 2 mins Air 50'/minute
Level off 120' 23 mins 25 mins Air -
Ascend to 60' 2 mins 27 mins Air 30'/minute
Stop at 50' 2 mins 29 mins Air 30'/minute
Stop at 40' 3 mins 32 mins Air 30'/minute
Stop at 30' 5 mins 37 mins Air 30'/minute
Stop at 20' 7 mins 44 mins Air 30'/minute
Stop at 10' 14 mins 58 mins Air 30'/minute
Ascend to Surface 1 mins 59 mins Air 10'/minute
Now consider this same dive breathing air, yet also using a combination of 50% Nitrox, and oxygen on the ascent. With the efficient use of these gasses, the diver is able to safely surface a full 20 minutes sooner than breathing air alone.
Action Depth Duration Run Time Gas Rate Descent/Ascent
Descend to 120' 2 mins 2 mins Air 50'/minute
Level off 120' 23 mins 25 mins Air -
Ascend to 70' 1 mins 26 mins Air 30'/minute
Ascend to 50' 1 mins 27 mins 50% 30'/minute
Stop at 50' 1 mins 28 mins 50% -
Stop at 40' 1 mins 29 mins 50% 30'/minute
Stop at 30' 2 mins 31 mins 50% 30'/minute
Stop at 20' 3 mins 34 mins 100% 30'/minute
Stop at 10' 4 mins 38 mins 100% 30'/minute
Ascend to Surface 1 mins 39 mins 100% 10'/minute
This certification declares that the diver has exhibited competence in diving safely to a maximum depth of 150' for durations that require staged decompression. Further, the diver has exhibited competence in safely planning staged decompression dives. This certification also includes gas planning and management for such dives. Below is an example of dive planning and gas management for a dive to the B-29 Bomber in Lake Mead, Nevada - which is currently at a depth of 150'.
Action Depth Duration Run Time Gas Rate Descent/Ascent
Descend to 150' 3 mins 3 mins Air 50'/minute
Level off 150' 27 mins 30 mins Air -
Ascend to 80' 2 mins 32 mins Air 30'/minute
Stop at 80' 1 mins 33 mins Air -
Stop at 70' 1 mins 34 mins 50% 30'/minute
Stop at 60' 2 mins 36 mins 50% 30'/minute
Stop at 50' 2 mins 38 mins 50% 30'/minute
Stop at 40' 4 mins 42 mins 50% 30'/minute
Stop at 30' 5 mins 47 mins 50% 30'/minute
Stop at 20' 5 mins 52 mins 100% 30'/minute
Stop at 10' 8 mins 60 mins 100% 30'/minute
Ascend to Surface 1 mins 61 mins 100% 10'/minute
A great majority of the diving science is calculated at sea level. Diving at higher altitudes requires the application of a theoretical depth chart which has been created using extrapolated data. Just look at the depth difference between a 100' dive at sea level and the same dive at 8000' and it is easy to recognize why this Specialty is so critical.
0 1000 2000 3000 4000 5000 6000 7000 8000 9000 10,000
10 10 11 11 12 12 12 13 13 14 15
20 21 21 22 23 24 26 26 27 28 29
30 31 32 33 35 36 37 39 40 42 44
40 41 43 45 46 48 50 52 54 56 58
50 52 54 56 58 60 62 65 67 70 73
60 62 64 67 69 72 75 78 81 84 87
70 72 75 78 81 84 87 91 94 98 102
80 83 86 89 92 96 100 103 108 112 116
90 93 97 100 104 108 112 116 121 126 131
100 103 107 111 116 120 124 129 134 140 145
110 114 118 122 127 132 137 142 148 154 160
120 124 129 134 139 144 150 155 162 168 174
130 135 140 146 151 156 163 168 176 182 189
Cavern Diving is a unique PADI Specialty. It may be the most skills-intensive of all the Specialties. In fact, it approaches the very boundary between Recreational Diving and Technical Diving. Cavern Diving constitutes diving in the region of a cave that is still exposed to sunlight. To do so safely, the Cavern Diver must be trained in many of the same concepts that Cave Divers utilize, yet not in as hazardous an environment as Cave Divers. This is training of the highest order, and the PADI Cavern Diver certification is one of the most under-utilized skill-sets in the PADI skill arsenal. Think of it ... learn many of the same skills that a Cave Diver learns, in a much safer environment! For the serious diver, the Cavern Diver certification is a must-do.

The Cavern Diver Specialty requires the same skill development as Cave Divers in the following areas: Buoyancy, Gas Management, Laying a Guideline, Hand/Light Signals, Team Diving Concepts, and others. If you have achieved Master SCUBA Diver and have numerous dives under your belt and think you are a pretty good diver and are wondering what is the next challenge ... this is it!

As a point of clarification for my personal practice as a Cavern Diver Instructor, please note the following. I teach the Cavern Diver Specialty as it is outlined in the PADI Cavern Diver Specialty Course Instructor Outline. Once this is accomplished, all paperwork is signed off, and the diver is certified as a PADI Cavern Diver ... then I offer another option. If the diver wishes it, I will orient him/her to the NSS-CDS Cavern Diver training protocol, separate from and in addition to the PADI protocol. This orientation has no connection to PADI and is considered unofficial by the NSS-CDS. Nonetheless, it is a valuable experience for anyone who may consider going on to Cavern Diver training from an NSS-CDS Cave Diver Instructor such as Jim Wyatt of Cave Dive Florida, who is one of the most sought after Instructors in the Cave Diving community. I have already been acknowledged for success in this practice, and more than one student has thanked me for helping him/her "... prepare for Jim Wyatt's training ...."
Diving with an specialized dive computers has become more and more common over the last sseveral years. The main value of diving with a computer is that it is capable of providing "progressive decompression" via a re-calculation of nitrogen off-gassing at intervals from 10-30 seconds. This offers a much more accurate dive profile for calculating decompression obligations. All dives are decompression dives, even though the Recreational Diving agencies have opted to use the terminology of a "safety Stop" to identify a decompression stop of three minutes at a depth of 10'-20' which is encouraged for all almost dives. Each dive computer has its own mathematical algorithm for calculating the decompression obligation.

Divers opting to utilize dive computers must be properly trained, as all dive computers tend to offer increased submersion times. Misinterpreting dive computer data could easily lead to a decompression-related injury or even death.
Diving safely beyond a depth of 60' includes special challenges. Major factors include increased water pressure, increased volume of gas per breath, breathing gas management, and nitrogen narcosis.

As depth increases, so does the ambient pressure. Breathing gas also compresses and the volume of breathing gas at 66' is actually diminished by a factor of three. In other words, a diver breathes three times as much gas at 66' as s/he does at the surface. This has to be a consideration for deep dives, as the breathing gas supply depletes at a much faster rate than the diver may be accustomed to in shallower dives.

An example of breathing gas management for a deep dive is to place a redundant air supply on the descent line, should a diver miscalculate gas usage or experience an unexpected delay before ascending.
Dry Suit diving offers wonderful benefits over wet suit diving, but is definitely more complicated. Often when diving in cold water, a wet suit diver becomes chilled. This usually doesn't happen to dry suit divers, as they are protected from full-body exposure to the cold water. Because dry suits rely on a layer of air to insulate the diver from cold temperatures, managing the air in the suit is a major factor of dry suit diving. As the diver descends, the air insulation compresses and is less efficient, not to mention the squeeze or "shrink-wrap" factor. More air must be injected into the dry suit to offset the volume that is diminished by the increased water pressure. Likewise, when ascending, the air insulation expands and produces undesired buoyancy. The expanding air must be vented to prevent an uncontrolled ascent. Also, a dry suit has mechanical elements which must be diver-monitored. Lastly, contingencies must be prepared for possible mechanical failures of the complex mechanisms. As in many aspects of life, there are trade-offs when dry suit diving. Wet suit diving is simple yet sometimes chilling, while dry suit diving is warmer yet more complicated and requires formal training to perform safely.
Efficient underwater navigation is one of the skills that "divides the sheep from the goats" among divers. Skillful underwater navigation is not only safer for divers, but also reduces anxiety. Dives to/from wrecks, reefs, and other underwater sites are accomplished skillfully, sometimes to the utter amazement of newly-certified divers. Of special imprtance, if divers become disoriented, this certification provides them skills to resolve the problem, rather than developing stress or even panic. Becoming disoriented may occur, even to the best divers - for example, if water visibility changes during the course of a dive.

This certification places emphasis on compass- and natural-navigation techniques. Multiple direction changes and "dead-reckoning" are learned, practised, and mastered. This is one of the major certifications among those who achieve Master Diver status.
Night diving introduces a whole new world to those willing to learn how to dive in darkness. Use of lights, special navigation issues, and sensory deprivation are major issues that trained for. Interestingly, some of the most exciting marine creatures only come out at night and others are much more easily observed on night dives. This course teaches the diver what special procedures to follow when diving in darkness. Extra attention is given to natural navigation.
Breathing oxygen enriched gas while SCUBA diving has completely changed the diving industry. It is possible now to dive much more safely, with less risk of having a problem of excess nitrogren in the body. The increased oxygen also causes some divers to feel less lethargic after they dive. Yet, these benefits are offset by the constraints associated with breathing oxygen-rich gas ... the human body can only have so much exposure in a 24-hour period before the lungs become inflamed. Also, a diver cannot dive as deep on Nitrox as s/he might on air. These positive and negative factors are critical to understand and practice.
Whether it is a piece of boat equipment, a fishing rod, or a missing diver ... having the skills to search for and recover a target is valuable. It may mean the difference between life and death. Search and Recovery is one of the diving skills that divides the sheep from the goats among divers. As exciting as it may be to find an anchor or stainless steel propellor, bringing a heavy item to the surface requires techniques that do not place the diver in jeopardy. This Specialty is often a foundation for divers who move on to professional fields of SCUBA diving.
Underwater Photography is one of the most gratifying experiences in diving. The marine world is incredibly beautiful, as divers know, but with this skill others who are not divers can also appreciate the wonders of the aquatic world.

Photo left taken on a North Carolina wreck. Photo right taken on a Catalina Island reef.
Underwater videography is one of the most rewarding diving activities there is. Documenting places and things a diver sees in a video format is incredibly exciting. Taking raw footage and creating a custom-designed movie is gratifying for the diver and all who watch. Below are a couple examples of diver-made videos using different formats.

Shark Dive (27MB)This video was shot using a Nikon E7900 Digital Snapshot Camera set on video mode & no lights. The close-up sharks are only two feet distance. It was edited using Windows Movie Maker.

Simulated Diver Rescue (35MB)This video was shot using a Sony DCR TRV-11 Video Camera, generic underwater housing & no lights. It was also edited using Windows Movie Maker.
An individual who achieves the status of Open Water Diver Instructor is almost revered in the SCUBA industry. Rightly so, as this person has exhibited the skills necessary to safely train non-divers to become safe divers. Accompanying that status is a tremendous level of accountability. People's lives are in the hands of the SCUBA Instuctor, as s/he must be thorough and scrutinizing to be certain each diver is truly competent.
Under the SCUBA Schools International protocol, the Dive Control Specialist is a combination of Dive Master and Assistance Instructor. This is a coveted status which is the first level of Dive Professional. A Dive Master often guides new divers in their initial diving experiences or in unfamiliar waters. The Assistant Instructor often supplements diver training by offering additional practice sessions, under the direction of the Instructor. The Dive Control Specialist plays a very valuable role in the development of Open Water Divers.
This certification provides one of the most valuable skill sets in the entire diving industry. This is true, even if the participant never intends to dive solo. This training teaches the diver how to be "solo-capable," meaning that if it were to occur the diver has the knowledge to deal with problems that might arise. It is not uncommon for diving buddies to become separated, especially if the visibility suddenly drops. For example, if a breathing gas problem arises while a diver finds him/herself solo, s/he deals with it personally, rather than being totally reliant on a buddy. I would encourage this training to any serious diver.

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