Cave Diving, Cave Exploration and Cave Mapping in Yucatan, Mexico

Highway 180 in Veracruz state Mexico

Protec Blog: Instructor Selection

Note: Fixed the link to the Protec Blog on 7/5/2009. Try it now. Sorry!

Matt has written an excellent essay on scuba instructor selection.  From his post,

Another important point is in how many different environments did the instructor conducted his dives activities in, is he or she experienced in warm water only or does the instructor have experience in cold water, black water, currents, wrecks or caves to relate within the training program to potential hazards or unique circumstances in various environments. There is nothing wrong getting in touch with a potential instructor and ask for a diving history report in various environments, experience in personal and teaching various levels of diving or a diving resume. This contact can be used as well to talk about course content and scheduling issues.

I would love to write a response, but I have to go and get a Trimix fill for my dive this weekend.  I hope you enjoy the essay.

July 31, 2009   3 Comments

Back on the loop

The advantages of a closed circuit rebreather in a shallow cave.

I have to admit that I recently neglected rebreather diving and instead spend most of my time off sidemounting. I pretty much used my rebreather for deep diving only. But recently that changed, I finished crossover training on the Poseidon Cis Luna Mk6 and right after that was with Howard, aka Scubadadmiami for a week of CCR Cave diving. And I am hooked on CCRs again.

Patrick Widdman on DPV and CCR

The Mk6 exceeded my expectations but this is not what this article is about. What I want to share here is my recent experience diving Ponderosa, Taj Maha, Nohoch Nah Chich, Grand Cenote, Carwash and Naharon. Generally all the dive sites have an average depth of about 30ft and Nohoch even being shallower with Naharon being the exception at 60ft.

In many posts on CCR forums, the Mexican caves are described as CCR “unfriendly” and honestly I do not understand why? Our recent experience illustrated that CCRs can be used effectively in these caves and enabled us to get to know whole sections of systems in only one dive.

Normally when I guide people open circuit I choose a cenote and then guide two dives to the most famous or pretty parts of the system. The dives are usually turned either on time or gas which results in returning to open water. The option to recalculate thirds does exist, however, my opinion is that it should be reserved for experienced divers with experience in the particular system. When divers elect to recalculate thirds, eventually the gas reserve becomes to small to be safe.

The advantage of the CCR is that you have a bail out radius which enables you to spend as much time as the scrubber will allow, normally about 3 hours which is a huge opportunity here in the Riviera Maya.

The cave systems here are like Swiss cheese with many different side tunnels and passages. They are also very shallow. These two characteristics combine to create a situation where divers have a very long range on an 80cuft cylinder. Depending on you gas consumption while bailing out and conservatism factor you want to build in you will have a radius of at least 40min in most places. There are other benefits worth mentioning:

  1. Once you come of the frequent traveled passages you will often encounter quiet significant amount of percolation that can seriously affect the visibility.
  2. Thinking about the lost line or lost diver scenario, imagine how your chance of survival or the chance of finding your dive partner will increase with an hours long supply of breathing gas.
  3. How many accident reports have we seen that speak about people drowning only minutes away from an exit, what would have happened if they would have been on a rebreather.
  4. Taking pictures on the way, on a CCR you penetration distance is not going to change because you stop at a place to take some pictures or simply take a brake.
  5. Think about a reverse block way back in a cave, how much more relaxed are you going to be, knowing you can stay there fro hours.
  6. No time or gas pressure to go to a certain part in the cave and therefore reduced chance of pushing limits due to being goal oriented.
  7. And many more

Of course this is a double edged sword and there are as well some negative aspects:

  1. Buoyancy is definitely more difficult.
  2. It is the perfect tool to bring people that where before limited by their air consumption far into the overhead environment and by that outside of their comfort and experience zone.
  3. With most units together with the bail out your overall size in the water column is bigger and therefore you need more effort to travel.
  4. Many ups and downs consume Oxygen and Diluent volume.
  5. Getting overconfident due to the feeling of having unlimited gas supply.
  6. Proper bail out gas and volume is never an issue until it becomes an issue.
  7. And many more

To have a real advantage with the CCR we have to change the way we dive in the cave. Instead of using it to go for that record braking long distance penetration why not stay closer to the entrance but get to know all the lines that are in that area.

For example, at Naharon we dove up the main line and did the Jump towards the double domes. We swam up that line until we reached 40min, or bail out distance. On the way we stopped several times to take pictures and simply stopped the timer while we did not go further in the cave. On the way we marked the double set of line arrows that mark the jump towards south western sac be. On our return we arrived back at the arrows and new that from this point on we had 30min for further penetration so now we did the jump and enjoyed the really unreal beautiful sac be section.

On the way there we pass yet another set of double arrows marking the jump that lead down towards Cenote Mayan Blue and again marked it. We continued in the sac be tunnel until we had reached 30min from the jump and turned our dive. On the way back we stopped again a couple of times to take pictures. We didn’t even have to take care about the time since we were well inside our bail out range.

Howard pushing a tank through....

As we arrived back at the Arrows we decided to make yet another jump and check out the line that leads towards Mayan Blue. After some time we turned from there and now did the entire return trip back to Cenote Naharon.

As you can see, we did in one dive what, in conventional OC cave diving style would need three dives. We had an average depth of close to 60ft with a 180min runtime, me carrying an 80cuf and Howard 2 40cuf bail out tanks.

Another example would be Carwash where we could use Lukes Hope to restart the 40min bail out range and therefore had plenty of time to visit the room of tears and all the different Ts in the back. On the way out we did the jump that leads to the back of the room and stayed there for like 30min just doing pictures and enjoying the decorations.

In Grand cenote we went down to the Cuza Nah Loop and could restart the 40 min each time we past a cenote which was awesome since this gave us the possibility to do the jump at the mid way of the loop and take our time while swimming down that line again taking pictures and having a great time. On the way back we continued the loop on the other way since we were still easy inside our bail out range.
And the same was done in all the other places.

All in all I really enjoyed this week especially the possibility to visit lines I have not been too in a long time. I really love to do complex navigation, see different lines and go back and forth and all around.

Another bonus, so to speak, was to get more experience on the Kiss Classic which I really start to like more and more for its simplicity, the 20min prep in the morning and the 5min tear down in the evening, the free chest, constant O2 flow which facilitates buoyancy and the general possibility to keep the same configuration than with a set of doubles.

For Howard it was great too because he really got to know quiet a bit of each system we dove at, although he only did ONE dive there.

Considering all of the above, I would call the caves here perfectly suited for CCR diving if you bring the right set of skills, a good attitude and some creativity to the table.

Of course there are always people that say OC backmount is the only way to go and others believe that OC sidemount is the best, then there are some that believe in multiple stages or scooters or I don’t know what else; Me, I think it all has its use and its just what you do with it that makes it valuable. Try to get the most advantages out of whatever equipment you use and try to work with the right tool for the job!

Keep the loop closed but your mind open!!!


July 25, 2009   4 Comments

Interview with Steve Bogaerts: Part 3 of 3

In February of 2009 my wife and I got pregnant with our first child, which is a wonderful joy as we were trying.  The pregnancy set off a chain of events which resulted in us moving back to the United States.  Well, that move created mass chaos in my life and the fact of the matter is I just didn’t have the bandwidth to maintain the blog.  I was busy moving, buying furniture, going to the doctors and getting my life restarted.  Luckily, some of the insanity is dying down and I can get back to some of my recreational activities like blogging.

Before we get to the third part, I want to thank Steve for being a wonderful instructor and for taking the time to participate in this interview.  His responses were well thought-out and I think will help people when they are considering instructors.  You can find Steve’s new web site at:  So, without further adue….

I asked, “You have a new harness on the market called the Razor, what can you tell us about its development?”

Steve answered, “Well as they say “necessity is the mother of invention”.

I originally designed the Razor Harness for use on Side-mount / No-mount exploration dives in very restricted cave where every piece of extra equipment tries to kill you.

The problem was that in many cases to get to the part of the caves where I was exploring required long penetrations using DPV’s and multiple stages thus increasing my equipment load considerably. But when I got to the area I wanted to explore I needed to be as small and streamlined as possible. I wanted some way to integrate these disparate requirements in one system.

Over the years I have dived just about every Side Mount rig on the market as well as various homemade versions.

All of them worked to a degree but none were ideal.  Like most Side Mount divers I spent a lot of time making modifications to improve the various rigs but was always constrained to a certain extent by the original design and never had a Side Mount harness that I was 100% happy with.

As my exploration dives became more and more challenging, particularly over the last few years, I started to run into the limits of both the equipment and the equipment configuration I was using.

Trying to squeeze myself into ever smaller places was pretty rough on all my gear. I was getting hung up and stuck quite often and in fact in the year of exploration leading up to the connection between Sistema Sac Actun and Sistema Nohoch Nah Chich I managed to destroy 3 different Side Mount rigs. I was running out of equipment to dive in.

I ended up making a simple No Mount harness to go under my Side Mount harness so that when the cave really started to get small I could ditch the comparatively bulky Side Mount rig and carry on No Mount.

The problem was managing all this equipment a long way back in very small cave usually in zero visibility while trying to run a line or survey.  I was spending too much time dressing and undressing while underwater a long way back in the cave and not enough exploring.

Also trying to make sure that I had all the stuff I needed on the right harness at any given moment was a problem and at various times I forgot line arrows or survey slates for example because they were attached to the Side Mount rig I had left behind me in the cave and not my No Mount harness.

Additionally having passed through a section of No Mount cave sometimes it would open back up again and then having a Side Mount harness again would have been an advantage so that I could swim more efficiently.

As well during this period I started exploring from a tiny Cenote called Por One which lay between the Sac and Nohoch systems.

Por One has a nasty no mount entrance where you have to descend down a very tight chimney in the shape of an S.

There was absolutely no way to enter wearing my Side Mount harness, even with both tanks off, so I would begin my dives just in my simple No Mount harness.

Once through the entrance the cave continued in no mount sized passage for quite a distance and often I had to crawl, wriggle and dig my way through to make progress.

Eventually the cave opened up a bit and again a Side Mount harness would have been good to have but there was no way to get my existing Side Mount rig through the entrance and beginning section of the cave.

I needed a simpler more flexible system that fitted my current, more demanding needs.  I decided to start from scratch and design a completely new harness for myself.   It had to function as both a No Mount harness and a Side Mount harness. It had to work with multiple stages and with DPV’s.   The harness also needed to accommodate a totally separate and removable modular buoyancy system.

Ideally the harness also had to meet the following criteria on my rather extensive wish list as well:

  • Small and light so as to be easy to carry on long treks through the jungle.
  • Comfortable to wear and easy to get on and off on the surface.
  • A simple design with no stitching or fancy hardware.
  • Rugged to stand up to the most challenging dives in the most challenging environments where it was going to take a beating.
  • Safe and reliable because my life depended upon its performance.
  • As low profile and streamlined as possible to allow me to fit in the smallest areas possible.
  • Easy to use in very challenging conditions.
  • Easy to adjust.
  • Easy to repair if and when it does get damaged.

Over many hours of brainstorming, lots of test diving and various “Eureka” moments in the middle of the night the Razor Harness finally evolved into what you see today.

There were several prototypes along the way but the final version that I am currently using meets all of my requirements and is by far the best and most flexible Side Mount / No Mount harness I have ever used and has made my exploration dives far more efficient and productive and safer too.

I finally have a harness I am totally 100% happy with and that level of comfort is directly translated into the difficulty level of the dives I can now undertake that I would have hesitated to do before.

After years of experience diving in Side Mount I really thought I knew what I was doing but the last  few years spent experimenting with the Razor Harness have completely redefined my approach to, and philosophy of, Side Mount diving.

It has been like an evolution for me and I feel like I have learned so much and become a much better Side Mount diver along the way and that has been a really enjoyable experience.

I soon realized that if it worked so well for me then the Razor Harness would work just as well for other divers as well.

I started teaching all my Side Mount students in the Razor Harness and noticed a dramatic improvement in their skills, abilities and comfort as well.   Their pace of learning accelerated considerably.

One of the best ways to really understand something is to teach it to someone else.

Teaching other divers to use the Razor Harness really forced me to think deeply about, and refine, all the skills sets and procedures and this has been a really helpful process for me personally as well as a lot of fun.

The current system I teach is the distillation of all that trial and error. That experience refined and streamlined equipment, skill sets and procedures.

Each of the components in the system is designed to fit together seamlessly and work as part of an integrated whole.  The Razor Harness is at the heart of this system and is the foundation of all my “Bogarthian” Side-Mount procedures.

My philosophy is holistic in approach and is designed from the inside out so that as additional layers of equipment are added there is no change in the core equipment, equipment placement, procedures or skill sets.

“Less is More”

The Razor Harness itself is simplicity and elegance personified with only 2 continuous pieces of webbing and 1 closure point.  It is simple, strong, rugged, reliable, low profile and extremely minimalist in design. It fits like a glove and is very comfortable to wear.  The Razor will fit anyone no matter what their physical size or shape and is quick and easy to set up and adjust so that each individual diver gets a custom fit using standardized hardware.  It can be adjusted at several points to ensure the optimal fit for each individual.  All the attachment points such as D rings on the Razor Harness can be adjusted quickly and easily to allow personalized positioning of equipment placement.  Extra attachment points can be added easily if required.  Weight can be added to exactly where you need it on the Razor Harness to optimize trim.

You can easily use any BCD you want with the Razor Harness either wing or jacket style or no BCD at all if using a Drysuit or light tanks and lung volume.

The beauty of not having an integrated BCD is that you can add whatever level of buoyancy is required according to tank size & material, total equipment load, environmental factors, exposure suit type etc.”

I asked, “Are there any other related developments on the way?”

Steve answered, “Yes I am currently working on a modular buoyancy control system specifically to go with the Razor Harness.

When I first started using the Razor Harness I was diving it without any kind of BCD, controlling my buoyancy with just lung volume.

That worked out okay just diving with 2 AL80 Side Mount tanks although at the start of the dive, when the tanks were full, I had to dive at the top of my lung volume and it did not really become comfortable until the tank pressures dropped 500psi and the tanks became a bit lighter.

I really needed a small amount of lift to compensate for the weight of the gas in the tanks at the start of the dive but did not want to add a large and bulky BCD.

In one of my “Eureka” moments I decided to try out a 2l Camelbak hydration bag that I had lying around as a BCD. The 2l volume gave me 4.5lbs of additional lift.

I wrapped the Camelbak horizontally around my lower back over my Razor Harness and held it in place by attaching a bungee cord to one side, running that around my waist and through the front loop of my crotch strap and clipping it off to the other side of the Camelbak with a small snap bolt.

I inflated it orally through the bite on mouthpiece of the drinking tube and dumped air out of it by pinching the mouthpiece between my thumb and forefinger while holding the drinking tube up.  You can also suck the air out of it if you want to really empty it or are in an orientation where dumping will not work.
This is a real advantage when I find myself head down twisted like a pretzel in a restriction!

The concept was so simple and yet it worked fantastically well.  I called it the “BAT Wing” which stands for Buoyancy And Trim Wing.

The BAT Wing is designed to be worn over the Razor Harness. In my opinion sandwiching the BCD between the harness and the body is not ideal for the following reasons:

  • You cannot remove the BCD underwater.
  • The harness restricts the BCD.
  • You need to use a bigger BCD to cope with the reduction of usable volume.
  • The harness may cause air trapping in the BCD making control of buoyancy, trim, gas dumping etc more difficult.
  • Inflating the BCD restricts the harness.
  • When the BCD is inflated it can make the harness uncomfortably tight.
  • If you leave the harness loose enough to allow comfortable BCD inflation the harness will not be as snug and streamlined as it would otherwise.
  • Layering BCD’s for redundancy is more difficult and compounds all of the other issues above.

The most important reason for me to have my BAT Wing over my harness is the ability to easily and quickly remove/replace it underwater while diving if necessary.

Having the buoyancy so low down on my body was the ideal position to help maintain horizontal trim and the fact that it is so close to my center of gravity helped to optimize control when changing orientation in the water.

The BAT Wing is positioned in the small of my lower back and the super low profile meant that I could enter very small areas of the cave with no problem at all.  If needed it was very simple to remove the BAT Wing underwater as it was worn over the Razor Harness just being held in place by a single small bolt snap.

When I got to No Mount areas I could either take it off altogether and leave it behind or wrap it around my butt mounted tank to get it neutral and make towing the tank easier.

When I get to No Mount areas I have 3 options; leave the BAT in place but suck all the air out of it to minimize the profile, take it off altogether and leave it behind or wrap it around my butt mounted tank to get it neutral and make towing the tank easier.

I quickly upgraded to a 3l version that gave me just enough lift (6.6lbs) to dive with a single AL80 stage in addition to the AL80 Side Mount tanks.

I have recently upgraded again to using the MSR Dromedary Hydration Bags instead of the Camelbak’s as they are better made, more rugged and durable and come in a larger range of sizes 2L, 4L, 6L and 10L.

The beauty of not having an integrated BCD is that you can add whatever level of buoyancy is required according to tank size & material, total equipment load, environmental factors, exposure suit type etc.

I am currently using a 2l for No Mount dives, a 4L for Side Mount single stage dives and a 6L for Side Mount multi stage dives.

In addition it is very easy to layer the bags one on top of another for redundancy.

While this system is very, very good I have a few ideas that I hope will improve it further.

At the moment I am in the process of developing a commercially viable modular BC system along the same principles specifically for the Razor Harness and hope to have something available very soon.”

July 15, 2009   3 Comments

Interview with Steve Bogaerts: Part 2 of 3

In the second part of this three part series, Steve Bogaerts answers my questions and one of’s reader’s questions about preparing for training and Steve’s philosophy on sharing the

course’s skill sets ahead of time.

As a bonus feature, I have included two videos that Steve took of me while I was taking my Advanced Side Mount course with him.  When this video was shot, I had about 30 sidemount dives and we were on day two of the course.  These videos were particularly useful in helping me developed a complete mental picture of what I looked like in the water and how some of my bad/non-existent habits needed to be modified or developed.   During the  course  Steve shot an entire disc worth of video that we reviewed each evening during the debrief.   We discussed each item that needed to be improved whether it was gear or skill.  We also shared some laughs and some good memories of the cave we dove earlier in the day.

Today, I review that video occasionally and have had other people shot video of me to tune up my skills and gear.  Video can be an integral tool at any level of training to help the student visualize his mistakes and his successes.  Now lets get to the interview!

Anonymous reader asked, “Thanks for the interview with Steve, I have a question or 2 though if you are  interested. I would like to know specifically what skills he covers in the various classes?

Steve answered, “I do, of course, have skill sets for each level of training however I am slightly reluctant to list them for several reasons:

Training to do skills that you are going to learn in a class does not make a lot of sense since that is what the class is for.

The most important thing to do is go diving, practice the basics and come to class with a open mind ready to learn new skills.

Practicing skills incorrectly reinforces errors and bad habits that are harder for me to break later if/when a student does come for formal training.

You need to a flashplayer enabled browser to view this YouTube video

The reason to get training is to learn new skills in a supervised, structured, safe environment under the

expert and experienced eye of an Instructor who can make corrections and knows exactly what he/she is looking at.

I would far rather my students waited until class so that I can show them exactly how to perform each skill the right way and then they practice that.

“Practice makes permanent, only perfect practice makes perfect”

You don’t know what you don’t know.

Some people will assume that once they have a list of skills that they can teach themselves and have no need of structured, formal training.

At best they will be missing out on a great deal and at worst making serious mistakes and potentially endangering themselves through lack of knowledge.

Worse, they may try to teach other people; which is like the partially sighted leading the blind.”

Hans:  What would you like to see perspective students do to prepare for your courses?

Steve answered, “Go diving; time spent in the water is invaluable.  You cannot learn to dive from a book or on the internet you need to put the theory into practice and get wet. Also work on general all round fitness and watermanship abilities.

Work on the essential skills: buoyancy, trim, propulsion techniques and all round awareness. You cannot add more complex skills until the basics have been mastered.

If you can comfortably hold your position neutrally buoyant, trimmed horizontally, at any depth in the water column and can fine tune your position with precise fin movements and buoyancy control using lung volume then that will make everything else much easier…………including my job as your Instructor!

Q. What do you suggest divers who do not have regular access to caves do to remain prepared for cave diving?

Steve answered, “If you don’t have access to cave diving where you are then go open water diving. If you can’t dive in the open water due to the weather then dive in a pool. There is no substitute for time spent in the water. The most important thing is to get wet and practice the basics.

In fact as the cave environment is both unforgiving and fragile it is not really the best place to be learning and practicing new skills. New skills should be practiced and perfected in the open water before entering the cave environment to protect both the diver and the cave.   When learning or practicing skills keep it simple, just do one thing at a time.  Make sure you understand exactly what you are trying to achieve and break complex skills down into their component parts.  Mentally visualize what you want to do and all the steps required for completing each skill.  Make sure you have a clearly defined sequence or structure to work through and follow that each time you perform a skill in order to build up and reinforce muscle memory.

Do not try and rush your skill execution “slow is smooth and smooth is fast”. As you practice your execution will become smoother and more efficient, you will build up muscle memory and the speed will come.
Core skills must be mastered before more advanced skills can be.

When adding more advanced skills they should build on solid core skills in a logical, systematic fashion.
One important point to remember is that practice only makes permanent. Only perfect practice makes perfect!  Make sure that you are practicing the skills correctly otherwise you are reinforcing errors.
This is the main reason for getting instruction from a qualified, experienced Instructor so that you learn the skills correctly in the first place.  Once you have that basic grounding then feedback while you practice independently is very valuable.

One of the best feedback tools is video. Get a buddy to video tape you while you dive then review and critique the video.

You need to a flashplayer enabled browser to view this YouTube video

In a couple of days, I will post the 3 and final portion of this interview.  I am glad I have had the opprotunity to bring this information to you.  I know my heart got pumping as I edited tonights videos.  I look forward to your comments and questions.

If you want any clarifications, please do not hesitate to contact me!  I will get you the inforamation you are looking for.

June 7, 2009   11 Comments

Interview with Steve Bogaerts: Part 1 of 3

Steve Bogaerts fitting a Razor prototype to Hans Kaspersetz

In the past two years I have trained under three different instructors.  Each had their own specialty and really expanded the breadth of my knowledge and depth of my skills.  I have been fortunate to develop strong relationships with these men and continue my learning through regular contact and diving with them.  I sought these instructors because of positive referrals from other divers and reputation.  Therefore, I decided to interview instructors here on so you can decide for yourself who you want to train under.

Steve Bogaerts, my sidemount and specialty cave diving instructor, has agreed to participate in our first interview.  Following is the first part of a three part series in which he explains his unique approach to teaching side mount diving.  I will be publishing the next two parts over the next week and a half.

I asked Steve, “You teach Side Mount and have an innovative approach which is breaking the course into three segments.  Can you tell us about each of the segments?  Why did you choose this approach?  What should a student expect to learn in each segment?”

Here is Steve Bogaerts’ answer.

Actually there are 4 levels.
Intro to Side Mount
Level 1 Basic Side Mount Diver
Level 2 Advanced Side Mount Diver
Level 3 Exploration / No Mount Diver

The Intro course is a 2 day program and Levels 1, 2 & 3 are all 4 days in duration.

Traditionally the Side Mount Cave specialty course has always been a 2 or 3 day program but I found that I just cannot do it justice in that short a time frame.

Steve Bogaerts building a custom Razor side mount harness.

I have many years and thousands of dives in Side Mount/No Mount configuration and it is just not possible for me to fit all that knowledge and experience into a single 2 day course.

In addition most divers are not really ready to be in true Side Mount cave after just a day or 2 in a brand new equipment configuration.

In my opinion that is unsafe for both the diver and the cave.

Nearly all of my students come to me via word of mouth recommendation.

The reason divers come to me specifically to take a Side Mount Course is because of my experience and expertise in this particular area.

I really want my students to be able to benefit from my experience and knowledge in the best way possible so that they get the very best training I can offer that is challenging, detailed and complete but at the same time enjoyable.

To achieve this over the last few years I have completely changed the way in which I teach Side Mount.

It is not just the course structure that is new but pretty much my whole philosophy of Side Mount diving, the skills sets and procedures, and the way in which I teach the courses.

When you completely change your equipment configuration from Back Mount to Side Mount a lot of other things are going to change as well and a whole new skill set is going to have to be learned and practiced.

Being a good Side Mount diver requires a great deal more thought and attention than just hanging 2 tanks off of the side of your body.

Before more advanced Side Mount skills can be learned basic ones have to be mastered and before we enter a more challenging environment we need to make sure our skills and comfort level is matched to it.

The course levels are all natural stopping points and divers can choose to remain at each level either permanently, as they have no desire to go further, or temporarily to get more experience before moving up to the next level.

Put very simply the Intro to Side Mount Course is a short open water only introduction to diving in Side Mount configuration for someone who has never tried it before.

This is not a certification level and represents the first 2 days of the Basic Side Mount Course.

The Level 1 Basic Side Mount Course teaches you the skills and procedures necessary to cave dive in Side Mount configuration but still in larger cave until further training and experience is gained.

Any new equipment configuration takes some time to master and this should be done in a low stress safe environment so the intent here is not to dive in very small cave.

The Level 2 Advanced Side Mount Course builds on the skills and procedures learned in the Level 1 course as well as adding additional skills with the intent to train divers to be comfortable and safe diving in true SM cave which increases the environmental hazards and psychological stress levels considerably.

The Level 3 Exploration Side Mount/No Mount Course gives you the tools to be able to explore effectively and safely in the most extreme environments one will encounter in cave diving.

Some people want to dive Side Mount but have no desire to go in small cave so the level 1 course is the perfect choice and a natural stopping point for them.

For those wishing to actually dive smaller cave then first they have to master the basic skills and procedures of diving Side Mount in large cave in Level 1 before entering the far more challenging environment of true Side Mount cave that is introduced at Level 2.

Levels 1 and 2 can be taken concurrently or with a break in between.

On completion of Level 2 at this point it is time to go diving and build up some experience in Side Mount configuration in all types of cave including the small stuff before moving on to the Level 3 course which is very intensive and demands an extremely high comfort level in very challenging cave while dealing with potentially very stressful situations.

A minimum of 50 dives in Side Mount are required before taking the Level 3 Course.

There are also a number of complimentary specialty courses that can be taken in Side Mount after either Level 1 or Level 2; Stage/Multi Stage, DPV and Survey.

These course all introduce different aspects of cave diving and give a diver the knowledge and skills to plan more complex and demanding cave dives while learning more about the cave environment.

Additionally they are all tools that anyone wishing to explore at some point will need as well.

Hence all 3 of these specialty courses are also prerequisites for the Level 3 course.

The Level 3 course is really aimed at divers wishing to do the most challenging and demanding cave diving possible with a view to exploration.

This course puts in to practice all the skills learned and experience gained to this point as well as introducing No Mount techniques and exploration methodology.

To a large extent the courses have evolved around the Razor Harness and are designed to compliment it and to get the most from it.

The Razor Harness is at the heart of my “Bogarthian” Side Mount Philosophy.

I want to thank Steve for participating.  If you have any questions for Steve, please do not hesitate to leave a comment here on the blog.  I will make sure we get answers for you!

May 30, 2009   10 Comments

Graf Zeppelin Trip Report from the Unified Team Diving Guys

I don’t have a lot of time tonight to write, but I thought you would be interested in reading about a diving expidition to the Graf Zeppelin. The Graf Zeppelin was Germany’s only aircraft carrier during World War II.   It is located about 40 miles off shore in about 250ft of water.  The Unified Team Diving guys organized an awesome expidition in Poland.    The dive vessel is 200ft long and is equiped with a huge deck, hyperbaric chamber and crane.   I suggest checking out the link, the photos and story are awesome.  I am so jealous.

May 22, 2009   Comments Off on Graf Zeppelin Trip Report from the Unified Team Diving Guys

A month, Task Loading and Self-Rescue

Well, it has been almost a month since I last did some diving.  I was hopeful about getting out this weekend, however the apartment search and getting settled took priority.  I started to collect up my gear for this weekend and about half way through I realized that I just couldn’t get my head into it. Even if I could find everything I needed and I could find the time, I am pretty sure I wouldn’t be emotionally prepared to get up at 4:30AM and trek to the boat.  On top of that it was blowing like hell all weekend and cold!  If I can get myself into an apartment this week, I will start to seriously consider getting out this weekend.

I was browsing my normal array of forums today and found a link to, “Task Loading Tips For Underwater Photographers & Videographers” by Becky Kagan.  It is a quick read and has some nice photos.  My experience aligns with Beckey’s. She writes,

“Task loading can come in many forms and it’s different for everyone day to day. Task loading can be anything physical to mental or a combination of both. It could be pushing an over weighted camera with lights in a strong current while trying to set up shots, positioning a model, dealing with sea sickness, a broken fin strap, and a depth and time limitation. All of these little problems can build up into one larger problem so it’s important to recognize when you’re overwhelmed and when to call the dive before it becomes dangerous.”

A month and a half ago, I was relining a silty side mount passage.  I had recently switched from the stock fin straps on my Avante Pros to spring straps.  The springs were a little loose and would slip off the heal sometimes.  When they slipped off the heal, they would unclip themselves from the fin and the fin would work its way off.  Well, the first time it happened I thought it was an odd occurrence and a one off.  The second time it happened I got pissed and then promptly forgot about it.  The third time I was in a low wide silty pristine sidemount passage with my reel in my hand.  The passage was small enough that I would not be able to reach my fin and if it came off, I might not find it.  And since I was 2000ft from the entrance I really wanted to keep both fins.  On top of the fin issue, there was nothing for me to tie the reel off to, there was no where for me to put it down and there was nothing I could get a hold of.   And I couldn’t make forward progress because the loose fin was precariously perched on my foot.

Immediately, a wave of stress washed over me.  I wasn’t sure how I was going to solve this problem without trashing the cave.  I tried to reach my foot a couple of times with my reel in hand.  That was a non-starter.  I didn’t want to pull the line off the last tie-off.  And I didn’t want to get entangled.   I did a little twister practice, but the passage just wasn’t tall enough for me to get my lef forward.  After some more struggle, I started to get frustrated and a little upset.  I wasn’t sure what to do.  I was task loaded and a little stressed.

I decided to stop and take inventory of the situation.  The first step was to just take a couple of breathes.  I had two nearly full tanks on and a stage waiting for me at the end of the line.  I had plenty of time.   I thought about the reel and tried to figure out what to do with it.  I needed to get both hands involved in the self-rescue.  I dogged the reel down and clipped it to my chest d-ring.  I got the line a little taught to keep for getting it involved with my other gear.  Then I stopped again.  How was I going to get my fin and stay neutrally buoyant and not trash the cave.  Hmmm……  I decided to give up on being neutrally buoyant.  The cave had a hard rock ceiling so I inflated my BC until the overpressure valve vented.  I pinned myself to the ceiling.   Now I had two problems solved, no reel and no hovering, plus I gave myself some more room to work.  This is where there was some acrobatics.   I pulled my leg up gingerly and reached down and grabbed the fin.  I reattached the spring to the fin.  I pulled my leg up again and replaced the fin.  I pulled the spring over the hell and used my other hell to work it up the back of my leg.  I felt relieved when the fin went back on.

I slowly let gas out of the BC until I neutralized, unclipped and undogged the reel and finished my relining and survey.  It was a pretty cool experience, the kind that comes from diving.  I managed my task loading by identifying the problems and solving them one by one.  I was able to accomplish the solution without trashing the cave and without burning a significant amount of gas.

That night when I got home I resolved to fix my fins.  I drilled 4 holes in each fin, one in the post and one next to it.   I put the springs on and then pass a zip-tie through the two holes.  The zip-tie captures the spring bracket and holds it in place.  Since I made this minor modification, I haven’t had anymore problems with those fins.  I was very satisfied with the whole situation.

So, if you become task loaded don’t get frustrated or overwhelmed.  Stop what you are doing and take a couple of deep breathes.  Then look at your gauges to confirm your gases and the time you have to solve the problem.  Take inventory of what is causing you trouble and consider solutions.  Then act on a solution, don’t move forward until you have fixed the friction point.   Methodically address each issue until you can move forward with a mind like water.  Remember, there is no hurry and there is very little chance things will improve if you do hurry.

May 17, 2009   3 Comments

Risk of ICD and Narcosis When Bailing Out?

Great write-up Hans. Welcome back to NJ. Drop me a line and we can go out on my buddy’s dive boat some time. I’m heading to Florida in 3 weeks for CCR cave and CCR trimix training.
I have one question about your mixes. You didn’t say what you used, but doesn’t picking a lighter mix for bottom bailout put you at risk for ICD? Not to mention the narcosis causing a significant pucker factor.

To answer your question, the fraction of He only dropped by 10% when I switched from CC to OC.  That is not enough to create ICD friendly conditions.  A much larger change in the gradient is theorized to be necessary to promote ICD.  Consider this, if I were to go OC all the way to the surface the first gas change would have a 30% change in  the fraction of HE, the second would have another 30% change in HE content.  These changes do not throw an ICD warning in V-Planner (Which is arbitrary by Ross’ own admission.) and according to the principles I was taught in Trimix class should be ok.  So ICD isn’t a big concern here.

On the other hand, the Narcosis is a concern and that is one of the reasons I executed the drill.  I wanted to confirm I could still function under stress with that END.  The results of the test indicated that I was more impaired then I anticipated though not impaired enough to switch to a richer B/O gas for that depth and those conditions.

This provides a segue into another poignant topic; I never dove open circuit Trimix.  Therefore, I do not have any experience at depth on open circuit beyond bailing out.  This presented an interesting revelation to me; being at 280ft on OC is a fundamentally different experience then doing it on CC, which is something that Patrick Widmann warned me about more then once.

Watching my pressure gauge move noticeably with each breath adds a new sense of urgency and compounds the narcotic effect.  I now believe it is worthwhile to execute a number of OC Trimix dives to get a feel for gas consumption at 10ATA or more; if for no other reason then to learn the confidence and gain the experience to bail out in a calm and collected manner.

I can’t think of any worse set of conditions then to have to go off my unit, for a real emergency, and then to worry about my OC gas consumption and how it will play into my mental state.

I have tested and calculated my SAC rate many times, and it is very predictable.  However, knowing it intellectually and the pencil and paper jockeying wasn’t able to reproduce the feeling of watching the gauge fall.  It is one thing to know on the surface that your tank will be dry in 10 minutes; it is an entirely different feeling to experience it running down that quickly.  My experience is that the intellectual pursuit and mental preparation doesn’t substitute for experience and the only way to gain experience is to go out there and try it.  This is something Steve Bogaerts repeatedly hammered home for me and it was at his urging that Patrick and I both made the investment to execute these training dives.  Patrick had numerous sub-100M dives under his belt on open circuit, so his experience was different then mine.  I had no sub-65M dives on open circuit and I am new to Trimix diving, so I experienced something very different.  By both of our admissions, bailing out was a very beneficial, if costly, drill and was worthwhile.

I have observed the following; any uncertainty, doubt or fear will be magnified in an exponential way when the lizard brain appears on stage.   Therefore, it is advisable to train to mitigate as many of these primal fears as possible thereby freeing your mind to deal the real issue at hand with a “mind like water” focus.  Fear, doubt, and uncertainty cause me to react in disproportionate ways, causing more difficulty, inhibiting a calm collected solution.  The solution or at least the way to mitigate this is to train.

For example, NASA trains their astronauts for years prior to each mission.  This is to mitigate the response of the lizard brain and to ensure they have experienced, not read about, every possible contingency they can create here on earth prior to the mission.  This same approach needs to be taken into diving, especially as I reach further into inner space.  Deep diving with exotic gases in an overhead environment with relatively experimental technology is a highly risky endeavor.

The risk is so great because there is a disproportionately high probability that the unit will completely fail leading to death; known in gaming theory as ruin.  Therefore, with such a great threat to life possible on every dive, it is incumbent on the diver to train all the situations, including total system failure in situations as close to real life as possible..  Sometimes it is easy for me to assume I will react the right way, I had trained bailing out in 40ft, 100ft, and 240ft many times.  However, the training in 240ft only lasted a couple of minutes and didn’t involve a vigorous horizontal swim; which, upon reflection, presented a substantially different set of environmental, psychological and physical conditions.  It is important to realize that subtle changes in the situation can result in dramatic changes in the outcome and experience.  The threat is that we believe that a similar situation is applicable and overlook the fundamental changes in the environment.  A prime example is people assuming that experience and skill wreck diving will translate into cave diving and vice versa.  More then one diver has died making this false and fatal assumption.

What I learned was that when I move to the next section of cave which drops to 350ft (105m) and presents significant environmental challenges, I will want a richer HE gas.  I also learned that I want to train bailing out and perform an orderly exit in the conditions I expect to be diving in.  I think before I go for Jill’s Chamber, I had better be comfortable exiting from Wakulla Room on OC.

I hope that answers your question.

May 8, 2009   Comments Off on Risk of ICD and Narcosis When Bailing Out?

Response to zzzzzzzz from Rebreather World

I posted a link to my article Last Dive at The Pit – Bailing Out at Depth over on  One of the users, zzzzzzzz, commented on it and I thought his comment was worthwhile reposting here with my response.  The indented copy is zzzzzzzz’s comment.

Good article.

WRT keeping on schedule, OC trimix should be running a set of schedules, allowing for aborted dive, short, long and maximum schedules. This provides all the needed flexibility in an emergency. Running a single schedule is not great.

Thank you! I write the articles for people to learn from and enjoy as entertainment.

The diver had the appropriate schedules. I am not sure where you read that we didn’t have the schedules. Seems like you made a bit of an assumption to the negative. Our desire was to stay on the nominal schedule. As you might imagine, the switch to the next schedule at depth can add an unnecessary amount of decompression and gas usage. Every minute at that depth translates into about 5 minutes of deco. A switch to the next schedule brings a 30 minute penalty, something neither of us wanted to be obliged too. A close reading of the article reveals that my one minute to make the switch was built in to our nominal schedules. We left the switch on schedule.

This is to distinguish the need for time to solve problems versus making an expeditious exit. Since you experienced issues, it is astounding that the OC diver’s schedules did not allow flexibility in running schedules. Certainly, a diver targets a nominal run time for a dive, however, not carrying contingency schedules is a fundamental training issue. Recommending that someone executes faster when encountering problems is not constructive since one cannot predict how long problem solving can take, especially in an emergency.

See above.

It is also quite okay to encourage better skills integration for enhanced performance, however, not because it is an inconvenience for the OC diver.

I see his recommendation in a different light. Optimally, I would like to be able to be swimming towards the exit while making the switch. That ability would cut at least 1 minute at depth and 5 minutes off of deco saving a little less then 18cuft of gas. Additionally, it would put me closer to the exit if there were another emergency, which out of respect to Murphy isn’t completely unlikely. I can’t remember a time when only one thing went wrong when things started to go really wrong. I think Santiago’s critic is correct in that I need to work towards the ability to swim and make this switch at depth. I can do it in 100ft, why not in 280ft? That is a valid question and needs to be figured into bail out planning and needs to be trained further to develop better muscle memory. I don’t think either of my CCR instructors would have let me walk without being able to do that skill while making an exit. I shouldn’t accept it either.

On deploying and stowing regulators, especially on the fly, an added option is to set hose lengths such that the regs drape around the neck to staggered positions. This can allow maintaining several regulators in a deployed condition, allowing more time and options for stowage.

This is not a bad recommendation though going back onto the loop and doing 2.5 hours of deco this way wouldn’t have been very comfortable. Again, this is a training and equipment issue and was only identified because I took the time to actually try it out.  I wrote that I have a similar problem when I dive OC with stages.  That should have been a warning to me that it would manifest itself when I dive CCR.  It is interesting that the problems we have in the shallows are magnified under the time pressure that comes with depth.

Thanks for taking the time to read my article and provide feedback! Your ideas help me to better flush out my ideas. Keep them coming

May 7, 2009   Comments Off on Response to zzzzzzzz from Rebreather World

Last Dive at The Pit – Bailing Out at Depth

If you have been following Quiet Diver, you know that I left Mexico a couple of days ago.  And while I was in transit, I was torturing you with stories that were unrelated to diving.  Well, this story gets us back to writing about diving!

A month or so ago Santiago and I made a dive at The Pit down the Lins/Walten tunnel.  It was a nice dive to 238ft (73m).   Santiago was diving OC and I was on the Megalodon.   After the dive we had some helium left over and we enjoyed diving together so much we decided it would be cool to do a dive to the back of Wakulla Room as a team.  Additionally,  we needed to pick up some tanks that were staged from the last project and I still needed to do my at depth bailout.   So, we got another tank of helium and decided to do the dive in a couple of days.  Well, as the date approached I was too overwhelmed with work and had to call the dive.  These dives require a lot of preparation and mental focus and if my mind is on other issues, then I can’t do the dive.

Well, it took me more then a month to reschedule the dive between work and social engagements.  But once we got the dive scheduled everything fell into place.  All the gases were blended, regulators prepared and dive plans cut.

The plan was to stage gas at 20ft (6m) and 70ft (21m) on a down line.  Then set the primary reel and stage gas at 150ft.  For bottom gas Santiago took double 80’s and a deep stage.  I took two 80’s of deep bailout and the CCR.  Normally, I would carry one deep bailout for this dive, however since I was going to purposefully bail out, I thought it would be wise to carry extra gas.  As well, I was diving with an OC buddy and I wanted to be able to donate gas in the event of a lost gas situation.  After staging all the gas, we planned to swim to Paul’s Rock, which takes about 16 minutes.  Paul’s rock is about 800-900 (274 – 278) linear feet (meters) from the surface at a depth of 280ft (86m).  Upon reaching Paul’s Rock, I would signal Santiago that I was bailing out.  We would spend one minute sorting out the situation and then make for the exit with haste.  After exiting the Bypass, I planned to switch back onto the loop to conserve gas and do a normal CCR decompression schedule.

I had a several reasons for bailing out at depth:

  1. Switch from a rich HE mix to a lighter mix and experience a change in END and confirm our choice of deep bailout.
  2. Go through all the steps of bailing out under the effects of depth.
  3. Confirm my SAC rate in that configuration and under the environment stresses.
  4. Practice bailing out under the supervision of a trusted dive buddy at depth and get critical feedback.
  5. Complete the drill because I made Patrick complete the drill and he was riding me about it.
  6. Feel the tanks as they get really light with HE in them.
  7. Breath open circuit gas at depth while hustling.  (I never dove Trimix OC.)
  8. Practice, practice, practice!

The dive went nearly as planned.  We reached our way point at 150ft (46m) a little late, through a little effort we were able to make up the time and we reached Paul’s Rock on time.  I turned to Santiago and gave him an okay.  He replied.  I then gave him the bailout signal.  I reached up and turned the knob on my BOV.  I breathed out a little to clear the regulator of water and took a breath.  As I completed the breath I was immediately hit with a case of nerves.  I felt a shot of anxiety and adrenaline wash over me.  It was totally unexpected because I had mentally rehearsed the drill a pile of times and had executed it in shallower water many times.  My brain went a little mushy.  I reached around and opened the bailout tank valve.  For reference, I have my bailout tank and diluent tank plumbed into a manifold, so I now had access to both.  I had switched from an END of 67ft (20m) to an END of 92ft (29m).  Plus I went from an “unlimited” gas supply to a very limited gas supply.

After opening the bailout tank, I pulled my regulator out to replace my BOV.  As I pulled the regulator to my face, I reached up and pulled the BOV out of my mouth and thought to myself, “Don’t flood your unit – close the BOV.”  I reached around and switched the knob, opening the loop!  Dur! I heard the bubbles and quickly stuck the loop in my mouth.  I switched the loop closed and cleared the regulator.  I thought to myself, “You idiot!  That is exactly what you needed to not do.”  I took the BOV out of my mouth put the regulator in my mouth.  Confirmed I was breathing the right gas and looked at my set point controller.  I needed to set the set point down to manual.  It took my four tries to get it right.  I kept setting it to 1.4 instead of manual.   Finally, I got it set and then switched my X1 over to bailout, which I achieved on the first try.  I opened the OPV and started to swim.  The whole switch over took about 1 minute.  However, it really felt like a life time.  We swam for 5 minutes exiting the Bypass.  I switched back to CCR and made all the appropriate adjustments.

As we ascended, I picked up the staged tank at 220ft (68m).  The tank had been there for almost two months.  It was covered in billowing clouds of bacteria.  All the hoses were slimy and I was very glad I didn’t have to breathe from it.

The rest of deco went smoothly and was without incident.  Santiago and I had very similar schedules and exited the water pain-free.

As I hovered in deco, I had a lot of time to reflect about the dive.  The first thing that came to mind was how glad I was that I took the time to do the drill!  I wish I had done the drill last fall, when we first agreed that we would do it.  There is no harm in practicing this stuff, except to your wallet!  There is only benefit and experience.  Because my Meg is so reliable, I do not often get the opportunity to bail in a stressful situation.

Bailing out at depth in the back of a cave is different then bailing out in the first 1000ft (309m) of Ginnie, any shallow cave in Mexico or on the Jodrey.  I had bailed out repeatedly in those environments and never felt the anxiety or lack of coordination that doing it in The Pit caused.  I was definitely noticeably more impaired at that depth, even with a 96ft (29m) END.  I was glad to learn that my SAC rate held even at depth with a shot of adrenaline and a hasty exit.  I was also glad that I was able to get all the required tasks completed.  After the dive, I checked my loop for water and there was very little.  The towels in the bottom of the can were just a little wet.  So the open look fiasco wasn’t too detrimental.  I was glad that I identified that problem quickly and resolved it.

Santiago was concerned with how long it took me to bailout.  As he was on OC and run time tables the whole dive, he really needed to stay on schedule.  He suggested that I might have been better off starting to swim earlier.  I don’t know that I agree.  I think it is critical, even if I waste 1 minute, to get everything set and then start to swim.  I can only do one thing at a time in a situation like that, especially if my lizard brain starts to emerge.  In past situations, I really fumbled things by trying to do more then one thing at a time.  I have learned I need to complete one task then move on.

In response to his remarks and my performance, I would like to go through the drill again at depth a couple of times and maybe a couple more times in mid-range water.  I think when I get back to Q. Roo, I will schedule another bailout before I start deep diving activities at The Pit.  I may have the opportunity to give it a try this summer here in NJ.

Santiago said I looked somewhat impaired as I tried to set the handset.  I agree with his observation, I was.  Either it was anxiety or being narced.  I think it was an insidious mixture of both.  I know that when I get scared or nervous, even in shallow water, my cognitive abilities diminish.  Mix that with some depth and you have a nice cocktail.

Lastly, he was unhappy with how long it took me to get back on the loop and the distance I swam off the line when I switched back to the loop.  Both are valid concerns.  I swam off the line to avoid getting entangled.  As the line exits the By-pass it splits in two and ends up above you and below you in ugly spots.  So, I swam away from it.  As for taking too long, he was right.  I had a lot of trouble stuffing the hose back on the tank and as I was about to pick up another tank I needed to sort the bailout first. I think I need to get looser hose retainers and practice with them a bit.  I have a similar problem when I am dealing with my OC stages.

I am very happy with the dive.  It didn’t go perfectly, but I learned a lot and we had a ton of fun.  I am grateful to for my friend’s observations.  When you are in the moment, you miss things sometimes and a neutral observer can add a lot of depth to the discussion.  Santiago is an excellent diver and I look forward to my next opportunity to spend time with him.  I am sad because that was my last dive at The Pit for a while!  I really enjoyed diving at The Pit, especially the deep dives.  The Pit is a spiritual place for me.  I see it as a cathedral of diving.  The spaces are so big and beyond normal scale that it inspires me.  Until next time, I will dream of diving at The Pit.  To be honest, I am going to miss all my friends: Patrick, Solomon, Alain, Steve, Etienne, Ross, Katie and Santiago just to name a few.  The last year and a half of diving has been amazing and I have many fond memories.  Thanks to all of you, my life is forever enriched!

May 6, 2009   8 Comments