TDI Diver News


Cave Training at a Young Age

I constantly have to remind myself that gushing about my new dive toys to my friends at lunch will only be met with confused facial expressions, while discussing teenage gossip with a group of seasoned divers will have the same result.


Caves and DPV’s: What You Should Know

With a DPV, as with overhead environments and rebreathers, a diver must master the basics first and foremost


The Top 3 Finning Techniques and When to Use Each One

A diver should be able to move through the water using their fins as the exclusive means of propulsion to increase efficiency and minimize the impact to the environment.


Is CCR Diving Right for You?

Fortunately, there is a way you can discover whether CCR diving may be for you without ever having to make that investment. It’s called the TDI Rebreather Discovery experience.


Skills Necessary to Conduct CCR Dives Utilizing Helium

There is no fluff when it comes to CCR diving. Each step has value and should be followed as prescribed. And that’s not just my opinion, it’s the best, safest and most secure way.


When Silly Drills Become Serious Skills

by Chris Richardson:
cave diver

A few years ago, okay… close to a decade (I’m getting old) I got together with a friend to have him evaluate me for some new Instructor Trainer ratings for technical diving. I had a few choices of who I could get together with to be evaluated but chose this particular evaluator because he has a reputation of being tough, was a friend, and he and I hadn’t been diving together before but knew each other well from being in the dive industry. Frankly I wanted to see if I was up to it.

We met up very early over breakfast and discussed the day’s plans. After lunch, real students would be joining us and he expected me to teach the class, but first we would go over and jump in confined water where he wanted me to demonstrate drills and skills.

When we got to the confined water site I was told to bring not just one stage, but two stage 80’s and a 40. I was in twin 104’s and drysuit. In other words, fully configured (kitted for those of us from the commonwealth) for a full on multi-stage dive.

First we did a buddy check and S-drills. Then he asked me to demonstrate, while neutral in trim, at no less than 8 ft and no deeper than 10 ft, stage management and gas switching from back gas through all three of the stage/deco bottles. Anybody that has ever dived with me knows that I ALWAYS want to do a warm up dive or two before doing any teaching, big dives, or being evaluated. This day I was going in cold and to my great relief I had no great difficulty managing the skill and surfaced to an evaluator with a somewhat evil grin on his face. He informed me that that was “pretty good” made a couple small suggestion for improvement then told me to do it again… without fins on! I must have looked at him like he was crazy because he laughed and asked if I had ever tried it before. I said no, of course not. He then informed me that “all” his students have to and that was that. Well… off my fins came, I settled down to the required depth, got myself in trim and neutral with some difficulty and then started the gas switching.

Yeah that didn’t work out so well.

It was humiliating and I provided great amusement to my friend. When he stopped laughing at me he informed me that I passed. I gave him a look and asked “WTF are you talking about?” He started laughing really, really hard and informed me that he does do the no fins but does NOT expect the student to do gas switches… then started laughing again. We had hadn’t fully communicated, he expected me to simply get there and get stabilized in trim and buoyancy, I thought he wanted me to fully do the earlier skill only without fins.

I then stated that, “I think I can do it, let me try again”. He raised his eyebrows and said, “Go for it”. I did, and I did. I took my time and if it had been a real dive with gas switches done so slowly I would have had to add another deco bottle to offgas the extra ongassing from how slow I was, but I did it. He was surprised and said he wasn’t sure he could manage it, he tried and he did it after a couple tries, we laughed and then the students showed up and we enjoyed the class.

I liked the skill as watermanship development for technical divers and use it when I teach (without the gas switch) but do tell people they should try it when they get comfortable with just the trim and buoyancy no fins drill. I also demonstrate both of these to my students to show it’s possible (I do only one stage however) I have had frustrated students protest that “the skill is stupid, why would you dive without fins?!”

Fast forward to two days ago.

Myself, and Edd Sorenson from Cave Adventurers in Marianna, Florida, were doing a fun dive together. The plan was he would show me some new cave in a well known cave system he had discovered and laid line in. The plan was fairly simple, we would scooter out a couple thousand feet with a stage, drop the stage and the scooters and go swim the new passage, come back, get stages and scooters, head back and deco.

The new section Edd found is pretty tight… not crazy stupid tight but certainly snug. We had to pay careful attention as to not stir up the bottom silt. There was one spot that was quite tight, almost crazy stupid tight. We reached the end of one line, turned around and Edd headed out with me behind, coming up to the restriction Edd slipped through, I followed and in the tightest spot it happened… I felt my left fin slip off my foot. I knew what happened. It’s a prototype fin that I had been testing, the strap was a little too big but not horrible and I knew that but wanted to dive the fin anyhow. The tight spot meant that I needed to stick my head and torso down, and then arch upwards to get through. Air went up my drysuit leg and into the boot and it popped the fin strap off. I couldn’t bend to reach my foot (okay, it was crazy tight there) so backed out to look for and put said fin back on. At this point the old saying “SILT HAPPENS” came true and needless to say, I couldn’t find it. After not finding it I came out of my silt cloud, showed Edd my “issue” and he decided to go get my fin… well that didn’t happen either. The good news, it’s not hard to move through low passage with one fin on, really. But as soon as we got out of the new passage into the main cave system which was much bigger the lack of a fin was MUCH more noticeable.

Using skills developed doing a silly drill, I retrieved my stage and my scooter, performed a gas switch to my stage, and started the scooter ride back. If you’re curious, scootering with one fin is easy at slow speed, not so easy at a medium speed and downright difficult at full speed on a good scooter.

The exit was uneventful; I was alternating between slightly embarrassed and quite amused I lost the fin. Upon surfacing, Edd ‘s first words were, “You made an event a non event”

We talked it over, I told him about the no fin skill, I admitted I was stupid to keep diving a fin I knew wasn’t a perfect fit and we discussed the event in the context of how we each could use it in teaching students so hopefully they could also turn “events into non events”. We also laughed about the fact that NOBODY but Edd or I would ever find that lost fin.

I’m writing this in the hope that other divers can learn to appreciate how important those safety, watermanship, and comfort skills we practice are. The place to fail a skill or a drill is in confined water while training, don’t short change yourself. Practice hard so you can dive easier.


4 Things I wish I’d Known Before My First Tech Dive

by Sean Harrison:
Tech dive

As I look back on the days when I first started tech diving, two things come to mind that have had significant changes – equipment and logistics. There have been such dramatic changes in equipment it is hard to highlight them all. The early tech equipment was nothing more than standard equipment that was reconfigured to meet our needs, it was not specialized, light weight, easier breathing at deeper depths or made of special metals. And we certainly did not have rebreathers, those did not come ‘til the late 90’s. Logistics, on the other hand, has gotten better but can still be a little tricky. My tech diving started in the mid-Atlantic states of the US where there were several boats that would take us to deeper wrecks and allow us to stay a little longer in the water. We also had a hard time getting the gas fills we needed for the planned dives. Things have gotten better in this aspect but here is a list of things to be aware of if you are considering getting involved in tech diving or have recently learned to tech dive.

1. Boats – not all boats are created equal. Dive boat operators as a general rule rely on the number of divers they take out per day, pretty simply math – the more divers they take out, the more money they make. When boat operators take out tech divers they will usually reduce the number of divers on their boat (space for additional equipment) and stay out a little longer to allow for decompression or rebreather divers – this means you may pay a little more to do tech dives off of boats. This also means you need to speak with the boat operator and make sure you can do the dives you want to do off their boats. Mixing tech divers with sport divers normally does not produce good results.

2. I have to go! – tech dives are not always deep but they are almost always longer than your average sport dive. Longer dives means better exposure protection (even in warmer water) read: dry suit, which means no peeing in the water, or does it. TDI recently released two good articles on this:

The P-Valve Struggle »
Girls Pee, Too »

The short version of these articles is, it is important to stay hydrated while diving and with hydration comes nature’s call. Lots of options to manage this situation so do your research before your next long dive.

3. I’m hungry – anybody that knows me knows I love my food and after a few hours in the water, I surface ready to eat! Diving burns calories and the colder the water the more calories burned. Tech diving from boats in many places also means longer boat rides, so getting back to the dock is not going to happen as fast as it does on sport dive boats. Bring along some good snacks or a sandwich to get you back to the dock. If you have a good snack on the boat ride back, you will be able to get started on the monster nap sooner.

4. Bring on the gadgets – not so fast. Tech divers are certainly gear geeks but they also tend to be minimalists and only bring what they need. A big part of what allows us to tech dive and stay underwater longer is minimizing air consumption; carrying more gadgets means not being as streamlined and increases air consumption. As you select gear, think about what kind of diving you will be doing, cave divers don’t need what wreck divers do and cold water wreck divers don’t need what warm water ocean wreck divers do. Also think about where it is going to go on your body or configuration. Too many things stacked on top of each other means you may not be able to access it when you need it.

If you are a planner or someone that likes to work through scenarios, technical diving is right up your alley. Plan out your dives, call the boat operators or local stores (if you can do the dives from shore) and find out what sort of support they can provide. If you will be diving from a boat, make sure you are clear with the operator what kind of dive you want to do and see if they will do it. Planning ahead is critical when it comes to rebreathers and traveling, not all locations support all rebreathers. Make an equipment check list and go through it before every dive/trip, with tech diving comes more equipment which equals more things to forget. Make sure that check also includes a save-a-dive kit, and that the spare parts now include the ones you need for tech diving. Plan ahead and have fun. A spontaneous tech dive can result in a spontaneous disaster. If you have not yet taken a tech diving course, consider signing up for the TDI Intro to Tech Course. This course will give a great overview of what to expect and what you will need.


What’s Your Life Worth? – Part 2

by Sean Harrison:
diver down
The “What’s Your Life Worth?” series is not intended to scare people; it is intended to provoke thought and some introspective viewing as well as self analysis. The intended end goal is to increase safety and reduce the likelihood of an accident. Keep this in mind as you read the series because while specifics could be pointed out (there is an unlimited number of examples unfortunately) the illustrations are written in a broad swipe and I have been careful not to write them in such a way as to combine accidents as if they were one occurrence. In this piece I am going to get back to the very beginning of the decision making process, the first step, if you will. What are you willing to pay for a course?

Course costs and what is included in those costs run the gamut, but one element that does not is what it takes to make a proficient and competent diver at any given level. To create a proficient diver at any level four key areas have to be covered: the basics of learning which involve knowledge development, applied skills, repetition, and muscle memory. Sounds easy right? Well it is, but it does not happen fast.

Everybody learns at a different pace and in different ways, meaning: time is required for the instructor to figure how the student learns and to ensure short term and long term comprehension. Unlike some learning events, scuba diving also requires skill performances which add another layer to the learning process – muscle memory. Muscle memory is so critical to diving that it should be considered life threatening if it is not achieved. Here is a basic example of what I mean by life threatening. If a diver has not practiced releasing their weight system to a point where it becomes instinctive in an emergency situation, they could drown because they cannot stay on the surface or even get to the surface. Why do I use this as an example? Because it happens time and time again, divers are found lifeless on the bottom with their weight system still in place.

Like muscle memory, knowledge retention is needed in emergency situations as well. It may not seem important when you are learning but when you need the information to make a split second decision, that’s not the time to realize “I don’t remember my instructor teaching me what to do in this situation”. Chances are good your instructor taught it or that it was covered in the materials for the course but… was enough time spent on it?

So you may be asking yourself, what does all this have to do with the cost of a course? You have heard the old saying “time is money”, well the longer it takes to achieve and ensure academic understanding and muscle memory, the more money it will cost. See, unlike many other activities you will do in your life, scuba is based on physics and physiology, two things you can never escape or defy. A few other activities also come to mind: sky diving, high altitude climbing, and rock climbing. Here is the thing with physics and physiology, you don’t need to have a complete and comprehensive understanding of them but you do need to understand the basics because every time you get into the water you enter a new realm unlike the one our bodies are adjusted to on land.

Moral of the story, don’t look for the cheapest class, it could cost you dearly later on, look for the course that is going to give you everything you need to be a competent diver at whatever level you are working towards and that includes if you are just taking your basic Open Water Diver course. Talk to the dive center or instructor and ask them: how much time do I get in the pool? How much classroom time do I get? If the answer that comes back is, “We do as little classroom and pool time as possible to keep the cost down”, find another dive center or instructor. Find the place that tells you exactly what is included in the course and gives you the response, “As much time as you need to feel comfortable”.

Diving is an amazing sport that takes you to places that some people only dream about and you get to see things that few people have seen, but it is not without its risks and that’s what makes it exciting. Do yourself and your loved ones a favor – take a quality course which comes with a slightly higher price tag. Keep in mind though that higher price tags don’t always mean quality so make sure you communicate to the dive center or instructor exactly how you feel. If you are not comfortable or feel you are not getting the training you need… let someone know.

dan ashkenazi

Basic Skills Tech Divers Tend to Get Lazy With

tech skills
When the first “Technical Divers” started to evolve and climb out of the primordial soup of the sport realm, some would argue they were light years ahead of the modern day sport divers of today who desire to make the same journey. Without getting into a great debate on the evolution of diver education, the modern day student does lack something of the days of old. The lacking factor is the relentless requirements of skill set repetition until those skills evolve into muscle memory that develops into a diver’s ability to have “Recognition Prime Decision Making Skill Sets.” “Recognition Prime Decision Making Skill Sets” is simply a model of how people make quick, effective decisions when faced with complex situations. One must ask, what happens to the tech divers who have demonstrated basic skill sets in training where they meet the requirements of certifications but do not seem to be very fluid or competent later in the execution of the same skill sets in future training dives or when needed? One thing we must ponder is, what is the culture within the “Tech Diving Community” when it comes to currency and proficiency of basic tech diving skill sets? English Anthropologist Edward B. Tylor defined culture as “the full range of learned human behavior patterns.” “This may be the most intuitive principle of learning, traceable to ancient Egyptian and Chinese education.” Aristotle once commented that repetition in learning “is frequent repetition that produces a natural tendency” and “the more frequently two things are experienced together, the more likely it will be that the experience or recall of one will stimulate the recall of the other”.

“Our humanity rests upon a series of learned behaviors, woven together into patterns that are infinitely fragile and never directly inherited.” – Margaret Mead

Diving culture is a very powerful influence within our community that is constantly evolving due to technology changes, the better understanding of science when it comes to diving physics and physiology, and the educational/philosophical differences among divers/training agencies. The hard and fast influences of diving peers, traditions, and the trials and tribulations of the pioneers before us are also factors that affect the evolution of learned behavior. So in the diving community we have the cultural traditions of the past, sub-cultures (separated ideology), and the cultural universals (ideologies that everyone accepts as the norm).

“The effects of repetition on a single association of stimulus and response with the effects of practice on the development of skill, which is something quite different. In learning any skill, what must be acquired is not an association or any series of associations, but many thousands of associations that will connect specific movements with specific situations.”

So whether you are “Tech Diver of Old” or a “Newbie Wet Behind Ears,” there are skill sets we all can, need, and do desire to improve/refresh upon or hone into a better mastery of. These actions take repetitive practice. Whether it is learning to deploy an SMB, performing a valve isolation and shut down, or working through managing a diving emergency, there are four stages one must swim through in skill development:

  1. The Novice – Mastering a craft does not happen overnight.
  2. The Apprentice – Realize your personal limitations.
  3. The Journeyman – Where the real work begins. Practice makes perfect.
  4. The Master – Unconsciously competent

“To become a master at any skill, it takes the total effort of your: heart, mind, and soul working together in tandem.” – Maurice Young

The law of 10,000 hours

Author Malcolm Gladwell, in his book Outliers: The Story of Success, states that “you need to have practiced for 10,000 hours, or roughly ten years, to become a genius at something. It means ‘success’ isn’t necessarily genetic, socioeconomic or generational.” So if you find yourself as the “Novice” standing on the shore dreaming of the water, or on a boat sailing down the road to “Mastery,” it can be concluded that it is not always an easy journey to log the 10,000 hours needed for obtaining mastery of a skill set. Similarly, there is another inherent problem that must be discovered and understood. Once you master a skill set it can be a very fragile learned behavior and it requires a lifelong dedication to maintain or one may slip from “Master” to “Journeyman” in an easy fashion. A famous quote by Confucius, says, “I hear and I forget. I see and I remember. I do and I understand.” Research agrees, and shows that we retain in memory “10% of what we read, 20% of what we hear, 30% of what we see, 50% of what we hear and see, 70% of what we say, and 90% of what we say and do.”

So what skill sets do we tend to get lazy on as tech divers? One of the first we have to look at is equipment configuration. All too often we find ourselves getting complacent and dependent upon the diving gear we have grown to love and trust. After all, we have the best BCD that has a dual bladder, tons of “D” rings, and it is very rugged and durable so we can load it up with weights and the biggest steel tanks (so air management is never an issue either). All jokes aside we cannot cookie cut our dive gear due to the individuality of every diver. So on every dive a “Tech Diver” should put in some dry time preparation on the dive gear to make sure the integrity, functionality, and dependability is there. During gear prep it should be determined that the equipment will perform proper when needed. Similarly, the routing and placement of regulators/hoses, cylinders, and the attached accessories should be ergonomically appropriate for yourself and easily accessible for use and deployment.

Second is tech dive planning – pen and paper time are still a must if want to try and keep “Murphy’s Law” at bay. A lot of divers tend to fall farce to believing “I have a dive computer and it will tell me everything I need to know.” Knowing run times, dive & gas management profiles, the objective, and problem contingencies for a dive is still imperative. Complacency can be unforgiving. Another part of planning is gas analysis. As a diver at any level you should know what is in your cylinder because people do make mistakes. Analyze your own gas mixtures so you know!

Third is weighting and buoyancy. These topics are subjects that “Tech Divers” tend to get complacent about. After all we said we have the best BCD and it can handle it right? Remember, “When the crap hits the fan – there are no time outs.” Knowing the buoyancy characteristics of your diving ensemble is imperative because it does have a direct reflection upon you trim and air consumption, which can affect other aspects of the dive. Being able to control your ascent rate and adjusting buoyancy to neutral during deco stops are directly related to proper weighting and is something one can always strive to improve upon. Some other skillsets that tend to become rusty without practice are:

  • Gas switching drills
  • Valve isolation or shut downs
  • SMB deployments
  • Different finning techniques (frog, backwards kick, scissor)
  • Equipment removal and replacement (stage cylinders)
  • Navigation techniques
  • Line reel management (tie offs, line retraction, entanglements)
  • Loss/disoriented – especially in overhead environments
    • Light failure
    • Silt outs
  • Drysuit emergencies (over inflation and flooding)
  • Hand signals used by tech divers
  • Dive rescue/prevention techniques (dive buddy monitoring, management of an unconscious diver)

An honest self-evaluation of yourself should be done, asking how you can become a better tech diver and member of a tech diving team. You should be open to evaluations by your peers because they may see things you do not notice about yourself. Finally, these actions as well as working with a TDI professional are all avenues one can employ in the journey toward the mastery “Tech Diver” skills. So how many hours do you have invested?

Darrell Adams – SDI/TDI/ERDI Instructor Trainer with Air Hogs Scuba in Garner, NC.