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Becoming a Rebreather Diver. By: Amanda Baker

9/30/2019

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    SCUBA is a constantly changing sport that seems to be alive itself at times. The fact that it is always changing is one of the things that I love most about our sport; you cannot have the same dive twice. Because it is never the same dive twice, there is always something new to learn or some skill to be conquered. The challenges in scuba diving are unending, and they are different for every diver. It was this that drew me to SCUBA after my very first open water dive years ago, I knew that one could never truly, completely conquer this beast of a sport, but the goal was simply to always be improving and learning.
I did not realize it at the time but it was this drive to try to better myself and master as many of the aspects of diving as I could that set me on the road to becoming a rebreather diver. Shortly after my initial certification I knew that I wanted to do more, I wanted to share my newfound love of the underwater world with everyone! I spent the next years working hard at mastering skills and building muscle memory while working my way up to Dive Master so that I could assist with classes. Through the experience I built over those years I met new dive buddies. They were technical divers, their gear and slang were so foreign to me, but I was intrigued. John was a tech instructor by this point so I began to learn the basics of this new world from him. I was hooked immediately!

    The thought of going beyond recreational limits was both scary and exhilarating. I began learning all of the specialized lessons that one needs in the Tech diving world. I learned decompression theory, how to calculate decompression stops, gas management, and gear rigging to name a few. I found this new type of diving to be even more addicting than my first breaths underwater. I decided to take things a step further so I became a trimix diver. This step required a lot of learning on the academic side of things. When it came time to actually dive trimix for the first time I was both excited and nervous. To this day, it was one of my favorite dives, I felt more alert than I had on similar dives, I quickly realized the advantages of “mix.”

    With these more advanced dives I found myself surrounded by people that I now consider mentors. I was constantly learning from them both in and out of the water. Being around people with more experience that me made me a much more knowledgeable and skillful diver. Quickly I began to notice that most of the people on the dive boats were not diving open circuit, but were opting for rebreathers instead. I became fascinated with these foreign, space looking, mystery machines. I drove both my friends and strangers on dive boats crazy asking questions about all of the different rebreather units. I watched videos, read books, and sat in on as many conversations as I could about rebreathers and rebreather diving. I wanted to know everything I could about them, and I challenged myself to one day become a rebreather diver.

    After years of technical diving things began falling into place for me to achieve my goal of becoming a rebreather diver. I spoke with, Joe Citelli, one of my mentors and asked if he would be willing to teach me how to dive this amazing piece of equipment that was going to allow me to broaden my dive world even more. To my great joy He agreed to take me on as a student, it was truly an honor. From the very first pool dive I was truly in love with everything about rebreathers. There was no sound, it was truly the silent world that Jacques Cousteau described after his first scuba dives.

    The class with Joe was truly amazing. Learning from someone with his experience was humbling. I was loving every minute and soaking up every ounce of knowledge that I could in our time together. The class itself was challenging, I learned how the SF2 unit worked. How to properly put the unit together, it is a whole new level to gear set up. I learned how to rig the unit so that it fit my body properly in the water. I learned how to handle situations that may come up underwater and practiced reacting to them properly. To date this was the most intense class that I have been through thanks to Joe. He never failed to keep hitting me with new challenges. As soon as I would master something and feel good about myself, he would throw something new at me. Under Joe’s guidance I felt like I learned more about diving and teaching diving that week than I had in the past several years. Things clicked together like never before and I came away from this experience not only a rebreather diver, but a better diver all the way around.
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    Nothing can replace experience, that’s why it is important to dive as often as we can and to practice skills on every dive. That’s what I am doing now, every chance I get I am diving the “breather” building muscle memory, confidence (both in myself and in the unit), and taking on this new challenge. While some dives I feel as though I have conquered it, there are other dives where I ask myself “What are you doing?” I think that is all part of the SCUBA journey, being confident enough in ourselves to know our limits, and to continually push them just enough to makes us better. I hope that I never stop feeling challenged underwater and that I continue to learn something on every dive.
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What’s your next challenge?
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Becoming a Scuba Instructor. By: Casey Fissel

8/8/2019

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Becoming a Scuba Instructor.

 The path to becoming an instructor has been one of the most amazing experiences of my life. I’ve gotten to see and do so many things that most people can only dream of. It all started during my junior year of high school when I first tested the waters of SCUBA. As part of my marine science class, I was able to participate in a Discover Scuba course. I wasn’t sure what to expect, but once I got in the water and started learning skills and getting used to the gear, I knew that a passion was born within me. For me, it felt natural – like I was born to scuba dive. From that day in Discover Scuba, I knew I wanted to further pursue my diving career and become a certified diver. However, it wouldn’t be until my sophomore year of college that I would get the chance to make that dream a reality.

    During my sophomore year of college at the University of South Carolina, I was introduced to the USC Scuba Club. I went to the interest meeting where I found out that, not only did the club coordinate dive trips, but they also coordinated certification classes so that new uncertified members could earn their open water certification. Needless to say, I joined and immediately signed up for the open water certification course. To say I was excited would be an understatement – I was more than ready to start my journey into the amazing world of SCUBA.


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     Enter John Baker, Amanda Baker, and Scuba John’s Dive shop. They were the shop that the club was using to certify us (little did I know, this shop would become so much more to me!). During the classroom session, I hung onto every word they said and absorbed the information like a sponge. Then came the pool session, and I felt exactly the way I did years before during Discover Scuba, like this sport was made just for me. We went over the skills needed to be an open water diver and got to try everything out in the safety of a pool, which was great, but I was ready for more. I couldn’t wait to go deeper and be able to experience the openness of the underwater world. My first taste of this vast underwater world would come through the checkout dives at Lake Jocassee. Here I would also meet Bill Routh and become familiar with Lake Jocassee Dive shop, who would be conducting our charters. Once out on the lake, we dove down to the training platform and went through a skills test. In total we went through 4 training dives over the course of a weekend. The last 2 dives were more fun based than skill based, as we had already passed our skill training. These 2 dives would be my first experiences in diving and they were amazing. We saw a sunken boat, played basketball underwater, and fed the fish (seeing/interacting with the fish was my favorite part because I absolutely love animals). From then on, my scuba career would only flourish.


    After becoming Open Water certified, I became an officer for the USC Scuba Club. My position as an officer was to coordinate the certification classes, which would ultimately lead to many opportunities that I would not have been exposed to had I not become an officer. Through setting up classes with Scuba John’s Dive shop, I built a relationship with John and Amanda, who would become my mentors and major players in helping me become the diver I am today. Around January of 2016, they offered me an internship at the shop, which I gladly accepted. Through this internship, I would be able to further my scuba career by obtaining my Advanced certification and from there, working my way up to Divemaster, over the course of almost 3 years. 
    During the time leading up to my Divemaster certification, as well as afterwards, I gained more experience diving than I ever thought I would when I was just beginning. I’ve gotten to dive in freshwater lakes, springs, rivers, low visibility, the ocean and various other conditions thanks to John giving me the opportunities to go. I’ve gotten to help with classes, learning how to work with people and help teach them. Though a lot of my experience I’ve gotten from just diving and learning first-hand, I owe a lot of my experience with helping people to Amanda. Through Divemastering and helping her in the pool and on checkout dives, I gained valuable first-hand experience helping people solve issues they may encounter while learning to dive. It was from working by her side and learning from her that I’ve developed confidence in teaching others. Because of John and Amanda’s mentoring and instruction, I felt confident going into my Instructor Development Course (IDC). 
    After becoming a Divemaster and seeing how you can make a career with SCUBA, I decided that I wanted to pursue becoming an Instructor. I wanted to be able to share my love of the sport with others and help them be able to experience the underwater world for themselves. I knew it wouldn’t be easy, but I believed it would be worth it. When I first started my IDC, I was a little nervous that I wouldn’t be good enough, but as the course went on, I realized I didn’t give myself enough credit. Because of my real-life experiences that I had accumulated up to that point, I was able to talk confidently during my presentations and I knew how to handle underwater situations during our open water skill examinations. By the end of my IDC, I had gained a new confidence and now I am officially an Instructor for Scuba John’s Dive Shop. When I first started out, I never imagined I would come this far as a diver. Becoming an instructor has been a huge accomplishment for me and I’m very proud to have earned this certification. I’m excited to help people start their own SCUBA journey and I can’t wait to see where this chapter of my life takes me!


    
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​Treatment of Decompression Illness in the Faraway. By: Greg Barefoot

8/5/2019

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​Treatment of Decompression Illness in the Faraway

Imagine that you are on a dive vacation off the coast of the Solomon Islands, when you notice
your right arm becoming progressively weaker by the minute. The symptoms occurred
approximately 15 minutes after surfacing from an otherwise uneventful dive that was made
using EANx 32. What could be wrong? If you thought decompression illness (DCI), then you
would be correct. What’s next? Our training tells us, to place the patient on 100% oxygen and
prepare for evacuation to the closest facility that could arrange for recompression. Did I mention
that the closest hyperbaric chamber is 1500 miles away and only accessible via aircraft? What
now?

The urge for exploration and discovery has led many divers to obtain additional education in
technical diving to expand the depths that can be explored. Along the same lines, divers are
traveling to more remote locations that may take several days to reach and therefore will take a
day or two of travel to evacuate. The combination of deeper, longer dive profiles coupled with a
remote setting, can increase the risk of decompression sickness and its long-term effects.

We know from our open water training that the biggest threat to a diver’s health comes from
breathing inert gas (nitrogen) at depth. Decompression illness occurs when the inert gas causes
injury to the diver. It can either be from pulmonary over-inflation syndrome, i.e. arterial gas
embolism, or decompression sickness, which is when nitrogen bubbles form in supersaturated
tissues. These bubbles effect the tissue where they are located by mechanical, embolic or
biochemical interaction.

It is well recognized that recompression is the treatment for decompression sickness since the
U.S. Navy recommended it in the early 1900’s. Recompression in a chamber while breathing
100% oxygen is similar to being at 2.8 atmospheres absolute (60 feet of seawater).
Recompression serves to compress bubble size and increase the diffusion of oxygen into the
cells and nitrogen out. Additionally, increased oxygen mitigates inflammation that occurs when
the body recognizes a bubble as being a “foreign invader”.

The effectiveness of treatment is tied to the time from initial onset of symptoms to the initiation
of treatment. We also know that 97% of symptoms will be relieved if a diver with DCI gets
treated within the first 6 hours of symptom onset. This drops down to the mid-seventies if the
diver gets treated later than 6 hours. When the diver is in a remote location where a
recompression chamber isn’t nearby, timely treatment can be difficult.

In water recompression with 100% oxygen to treat decompression illness has emerged as an
alternative to prolonged evacuation to a recompression chamber. This involves resubmerging a
diver with decompression illness back into the water, which effectively recompresses the diver,

in an attempt to reduce or eliminate symptoms. Even though it has been used as early at 1924,
the diving medical community has not widely accepted its utility. The negative stance likely is
related to the potential complications. The list includes: drowning, oxygen toxicity, worsening of
decompression sickness due to additional ongasing, hypothermia, and dangerous marine life.

These risks are mitigated by using 100% oxygen to prevent additional ongasing as well as using
a full face mask (FFM) to prevent drowning in the event the diver becomes unconscious.
Additionally, appropriate thermal protection can be used if the decompression time is long.
Oxygen toxicity is also mitigated by using the FFM or gag strap and keeping the maximum
depth to 20 fsw (1.6 ATA) as well as having the ability to provide and air break.

There are also contraindications to placing a diver back into the water. They include: cardiac
arrest, airway problems, severe rapid breathing, shock/clinical instability, vertigo, altered mental
status and coughing up blood. Some relative contraindications are: hypothermia, anxiety,
isolated hearing loss and lack of diver support or training.

There are multiple protocols that are available, all of which involve return to the water with either
a gag strap or FFM, and an adequate volume of oxygen, a stable platform, and a tender with a
tether. The tables suggest depths from 20-30 fsw breathing 100% oxygen (1.6 ATA- 1.9 ATA).
They require a certain time at that depth with a slow decompression on 100% oxygen until the
surface is reached. Even if symptoms resolve, most tables recommend follow up evacuation to
the recompression chamber.

With the increase in popularity of diving in general and technical diving in particular, along with
the ability to travel to remote locations, there is an increased risk of decompression illness.
When an event occurs, the diver has two choices: surface oxygen and evacuation with the
potential to delay recompression or reentry into the water for recompression. When a team has
adequate equipment and training, in water recompression gives one the peace of mind, knowing
that they have the skills to mitigate a decompression illness event in faraway places.
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​What it’s Like to be a Lake Murray Diver. By: David Neely

2/5/2018

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“What do you see down there?” Says the passerby as I trudge out of the water, fins in hand, water still pouring off of me and the equipment on my back. “Mud and beer cans” I jokingly reply with a smile.

As much as we locals like to joke about the quality of the water found in our own Lake Murray, it’s one of the few places left where one can look to discover remnants of the past if they’re up to the challenge. Recently, WLTX collaborated with Scuba John’s Dive Shop to put together a segment on things that have already been found in Lake Murray. So now that we’ve seen what’s under there, I’d like to answer another question: What’s it like to dive there?

An experienced diver knows that every dive environment presents its own unique challenges. The ocean has waves and currents. Northern waters such as the Great Lakes are frigid year-round. Overhead environments such as wrecks and caves require careful navigational tactics and gas planning. Lake Murray is no exception.

First, let’s address the car-sized catfish in the room: We don’t affectionately call it “Lake Murky” for nothing. Visibility can range anywhere from zero to 20ft depending on location and luck (we’re not yet sure what causes the variance in visibility at locations such as the Wyse’s Ferry Bridge). This is mainly due to the local soil being rich in clay,
which is the finest of all rock particles. Most of Lake Murray’s bottom is a thick layer of silt and mud. Because of this, good buoyancy control and fin techniques are important. Any contact or fin kick towards the bottom is certain to leave the diver and his buddies in a cascade of silt.

Pretty much all of the other challenges Murray presents (aside from the occasional careless boater and discarded fishing line waiting to tangle itself in your gear) arise from this lack of visibility. At about 30ft you’ll reach the first of what’s called a thermocline. A thermocline is a gradient in which the water temperature immediately drops because of the sun’s rays not being able reach it. This is the point at which ambient light begins to dim as well (in other words, it gets dark). At about 60ft, another thermocline is reached and virtually all ambient light is gone unless the visibility is good.
 
Lights and backups lights are required to see at this point. Even if it’s 80 degrees Fahrenheit on the surface of the water, temperatures can get down into the low 50’s past these thermoclines. Drysuits are a necessity to
keep the diver warm on long, deep dives. With these challenges come psychological considerations as well. Some find it claustrophobic enough to be breathing underwater, let alone when it’s dark and the visibility is limited. Even with careful technique, sometimes “silt-outs” happen and it’s important that the diver can keep a level head and work their way out of a problem in the face of one.

Now from a training perspective, this can be a good thing. Here at Scuba John’s we take full advantage of the fact that Lake Murray is a challenging place to dive in order to produce divers who are comfortable and competent in
the water. Lake Murray diving may not be for everyone, but for those who will rise to the challenge, it can be a most rewarding experience of diving into history and the unknown.
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Certified but Not trained

11/22/2017

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Hi! My name is Benjamin Matthews. Six months ago, I joined the SCUBA family. I took an open water course at a local shop, and after two weekends of classwork and dives, was certified. Needless to say, I was ecstatic; I couldn’t wait to find a diving buddy, and start logging dives. I felt that I knew everything I needed to be a “great diver” — after all, I was certified! I very quickly learned how wrong I was.

As I started getting dives under my belt, I began to realize that although I had been “certified,” I had not been trained. I had all the head knowledge that I needed; I could recite virtually every procedure in the book, I knew what I was supposed to do and when I was supposed to do it while I was under the water, and I had every acronym and signal down pat. Unfortunately, this knowledge only helped so much since I wasn’t properly trained on how to apply what I had learned during the classroom lessons.

Could my scenario have been avoided? Honestly, yes. Looking back, there are a few pieces of advice that I wish I had known beforehand, so that I ended up not only certified, but trained as well. I’d like to share the advice here, so that others who may be thinking about getting certified don’t end up making the same mistakes that I did.

The instructor, not the company, is the most important part of training.

I have lost count of the number of times that I have read this since my class ended. Every dive blog seems to pass this advice along, and I must agree with it. I fell into the trap of thinking that there was only one “good” certification company, and that the rest were subpar. I’ve since learned that this is not the truth. When it comes down to it, the company only certifies you, it’s the job of their instructors to train you. At the end of the day, it doesn’t matter if your open water card contains three letters, or four letters—what matters is that you are trained, and know how to dive properly.

If I could rewind the clock, and give myself some advice, I’d tell myself to be patient, look around at all the local shops, and take the time to meet the instructors that would be training me. I would tell myself to “listen to my gut,” and don’t ignore the first impression that the instructors leave. I had heard this advice before, but it wasn’t until after I was certified that I realized the true importance of it.

However, after meeting the instructors at Scuba John's Dive Shop and seeing how they work with their students (and tossing me a free lesson or two as well), I could see first-hand how a good instructor can make a big difference. To those who are going to take their open water course, I can’t stress enough how important it is to find a good instructor who will take the time to work with you, and seek to meet your needs.

During training, the size of the class is important.

When I took my open water certification course, the class was full (if not overflowing). This size lead to large amounts of down time, while the instructor checked off the other students. Unfortunately, it also meant that our skill checkoffs were rushed, and there was no time to loop back and practice skills that we weren’t comfortable with. We were told that to practice any skills we were needing help with, we would need to book a one-on-one session with the instructor, because there wouldn’t be time to review during our training dives.
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I would advise those who are planning on taking a course to ask their instructor how big the class sizes are. I would make sure that the class sizes have a hard cap, so that they don’t get too big. You want to make sure that the classes are small enough so that you and your instructor will have plenty of time to answer any questions that arise during the classroom portion, and have extra time in the water to review and practice any skills that need it.

Habits picked up during training stick around.
This advice is bittersweet, because it can go both ways. The good habits that I learned and reinforced during my certification course stuck with me. Unfortunately, the bad habits that I picked up, and didn’t correct, continued to plague me until I started dedicating dive time to correct them.

As an example, during my class, we were required to stay on our knees on the bottom of the pool/lake while the instructor wasn’t working directly with us. To keep us down, we were heavily overweighed (I personally wore 10lbs more than I needed). Because we were carrying excess weight, several members of the class, myself included, got into the bad habit of using our BCDs as “elevators.” When I began diving for real, I found that I would subconsciously be making the same mistake of “riding the inflator” up and down, rather than taking the time to properly weigh myself beforehand.

To those looking to get certified, let me encourage you to search for an instructor and a program that will train you under realistic circumstances. If possible, look for a program that will teach you how to execute skills while being neutrally buoyant, rather than on your knees on the bottom. A good instructor will make sure that you are trained under optimal conditions, so that when you begin diving after you are certified, you already know what the best habits are, and are familiar with the feeling of diving correctly.
In short, to those who are getting ready to take an open water course, don’t fall into the trap of only getting certified, without getting trained. This was a mistake that I made, and I wish I could rewind the clock and do things a little differently. I can’t emphasize enough the importance of finding an instructor who is willing to work with you, and your needs. Your instructor will be an important resource for you, both now and in the future. Remember, if you find yourself struggling at any point during the class, say something to your instructor. They are trained, and will be able to help you fix any issues / difficulties you are having. If you are able to avoid forming bad habits during your course, diving will be much more relaxing and enjoyable. I bid you all the best of luck, and happy diving!
--Benjamin Matthews
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Every Dive is a solo dive!

9/19/2017

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Every Dive is a Solo Dive!


The term “solo diving” has brought up many questions and concerns for years within the dive industry. Some divers see solo diving as reckless and dangerous. Others see it as their only way to dive because of scheduling and inability to find a dive buddy. However, with proper training and experience I believe solo diving can be done safely.


While solo diving, there are several risk you must accept. Obviously, the first is a dive buddy. Divers tend to worry that without a dive buddy they wouldn't have a back up air device for an out of air emergency. However, solo divers are trained to dive with a redundant air source. This is not a problem with proper training and practice. During a solo diver course, students learn advanced gas planning procedures to know exactly how much air they would need for the dive and they plan reserves. The biggest thing you lose with solo diving is a redundant brain. Your dive buddy can help if you become unconscious, panic, or have other problems that hard to deal with by yourself. This is why solo dives shouldn't be pinnacle dives. When divers go alone they do so in a familiar environment. You also lose some of the joy of sharing the experience of the dive with your buddy. However, none of this makes solo diving bad. For some people is the only way they get to go diving.


What I want to talk about is the mindset that every diver should have before entering the water. The mindset should be that every dive is a solo dive. This means that you should be a self-sufficient diver. One thing that I stress the importance of in all of my classes is the importance of self-sufficiency. While many of the dives that you do take place within buddy, it is important for you to be able to handle bad situation on your own if necessary. While diving you may find yourself alone. It can easy to lose a dive buddy in bad viz, in large groups, and if your not paying attention. You need to be able to handle whatever may happen if you find yourself alone. Below I want to give you a few tips help you become a more self-sufficient diver.


How to be a self-sufficient diver.

1. Plan your dive and dive your plan.Before every dive, you should take the time to plan. Whether you're diving solo or with the buddy it is important to plan out the following at minimum: maximum depth, maximum time, minimum air pressure, and dive leader. I was talking to a guy who investigates dive accidents. He said that a majority of the accidents investigated, the divers did not have a dive plan. You can greatly reduce risk by simply planning your dive.
2. Prevention
Another way to be self-sufficient just take a preventative mindset. This means to stop the problem before it happens. For instance, don't dive with gear that isn't working correctly. Believe it or not, people have died diving with gear that they knew was faulty before entering the water. Another way to prevent problems is to dive with the proper equipment. An entanglement issue is much easier deal with if you have a line cutter or a dive knife. Having a back up flashlight can make all the difference if your primary light fails. Don't dive at night or in dark water without two flashlights.

3. Know your gear.
Take time to play with your gear above water. Develop muscle memory so deploying you're accessory items is not a chore. Many times the first time divers use their emergency equipment is in an emergency. This is not the best time to become familiar with new gear. Go to your local dive site and do a dive just practicing with your gear.

4. Dive Often
Diving skills are perishable skills. If you don't use them you will lose them. You can't expect to be a good diver and only dive a few times a year. This goes for everything in life. You get better as you practice. Local dive sites may not have the best diving conditions in the world, but it is place to practice and become a safer diver.


5. Continue Education
Continue learning and continue taking courses. It will help challenge you and push you to the next level. The SDI solo diver course is a great learning experience. It will push you and make you think. You will learn new skills and how to become more self-sufficient in your diving and planning. Plus courses are great way to make new dive buddies!


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The BENDs: Decompression Illness 101

7/6/2017

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Over the years I have talked many divers that do not understand what is happening in their body during a dive. So I thought I would write a blog to get you thinking about it. This is in no way a comprehensive article that will give you a expert knowledge of DCI (decompression illness) but will hopefully cause you to think. Also, i am not a medical doctor so do not take this as medical advice. If you suspect you have DCI contact Divers Alert Network and medical services immediately. 

Although we still consider a good deal of what we know about diving physics to be theory, much of what we understand today is testable and repeatable. For instance, if I descend on SCUBA without equalizing my ears I will experience pain and possibly rupture my ear drum. And if I hold my breath on SCUBA and ascend, the air trapped in my lungs will over expand and rupture. Obviously, neither of these are good things. They are both painful and can result in serious injury or death.

But what about things happening in our body that we don't feel and may not feel until hours after a dive?  

​Decompression illness, also know as the bends, is a very real thing and people do die from this malady. The cause of it is breathing gas (air, nitrox, trimix) under pressure and coming up before you body has time to properly offgass. This can look like coming up too fast or staying down for too long then surfacing. It is a having much more pressure in your body's tissues that the pressure that surrounds your body. We are not talking about pressure from the air compressed inside the scuba cylinder, but the atmospheric pressure that the water creates around us at different depths.

From sea level to roughly 60 miles straight up towards space, our atmosphere that we live in creates 14.7 psi or 1 atmosphere of pressure. This is the weight of air at sea level. The higher we go in altitude the less air pressure there is. When we go diving the atmospheric pressure is doubled just at 33ft deep and pressure builds the deeper we go.

So what's the big deal? Why does this matter?

Well, look at it this way. If you haven't dived in the last 24 hours, the pressure of the gasses inside your body is considered to be at equilibrium with the atmosphere. In other words, the pressure of the gasses inside your body is equal to the pressure of them around you.

When you dive on SCUBA and breathe at depth, your body's natural response is to equalize to the atmospheric pressure around you. If you are at 33ft or 2 atmospheres, twice the pressure of earths atomsphere. At that time you are breathing in twice the amount of the gas molecules with every breath than you would at the surface. You body begins to store the excess gases into your bodies tissues to try and achieve equilibrium at that atmospheric pressure. We call this ingassing. At 132ft or 5 atmospheres you would be ingassing 5 times the amount of gas molecules with every breath than you would at the surface. This should help explain why the deeper you go the less time you have.

Our primary concern in recreational air diving is the gas Nitrogen (N2).  This is the gas that limits our time at depth and causes DCI. There are other forms of DCI with helium based mixes and oxygen toxicity issues with nitrox but that conversation is for another time.  Dive tables and dive computers helps track the intake of these gases in your body and give us No Decompression Limits (NDLs) which are time limits that we can stay underwater without required decompression stops. These NDLs help to keep us safe and avoid DCI if we maintain safe diving practice such as, slow controlled ascents, 3-5 minute safety stops, proper hydration, and etc. Now there is no guarantee that if you do everything correctly that you will not get DCI but it is unlikely. Most DCI occurrences are diver error. 

You need to develop the mind set that every dive you do is a decompression dive. When you go down and breathe gas under pressure you are ingassing excess gases. When you ascend you begin the first stages of offgassing the excess gasses. During the ascent it is important that you control your ascent rate. The current recommend ascent rate is 30ft per minute. That's 1ft every 2 seconds. This gives time for the gas to safely come out of your system which in turn reduces the risk of DCI and lung over expansion injuries.  

You are considered totally offgassed 24 hours after you last dive. While we ingass rapidly at depth, it takes time to offgass. You should notice that when you are planning multiple dives in a day that your NDLs are less for your 2nd & 3rd dives. Some divers call this the nitrogen penalty. I don't see it as a penalty because these NDLs are greatly reducing the risk of DCI. 

I wrote this after talking to a group of divers recently who was taught to follow their bubbles up and let the bubbles beat them to the surface and judge if they should go back down according to how their body felt after the dive. When i asked them which bubble do I follow? The big ones, little ones, medium ones?? None could answer me. This DCI we are discussing is happing in our bodies on a molecular level. We can't see and generally don't feel symptoms to long after the dive. Some cases reported no DCI symptoms until the next day. So don't base your diving plan on following bubbles and "I feel fine after the dive". Based your plans on what doctors and scientist have been studying and developing over years of research. Use your dive computer or table to plan dives. Read and research this stuff as much as you can... I believe the more you know the safer you can be. It is arrogant to think it can't happent to you.... it's science! 

Here is a link to signs and symptoms of DCI

Here is a link to the treatment of DCI

Check out this video from TED Ed on decompression illness. It is a great visualization of what is happening inside your body when you dive.


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Spearfishing Tips

6/7/2017

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Here is a video that I created with some spearfishing tips. Hopefully this video will help improve your spearfishing game!  The viz was low when when I shot it off the Charleston, SC coast, but that is when spearing is at its best! Let me know what you think!
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​Non-Certification  Personal Training Course 

2/7/2017

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Many divers feel the need to get a certification card for every course they take.  That’s ok. Some divers love their card collection. I’ll admit it, I like mine too! There has been much time, study, money, and effort to get to where I am.  So again, there is nothing wrong with having your cards. However, there are many divers who have a bunch of cert cards but their diving is a testament of how little they know and practice. Don’t be that diver!
 
I have always considered myself to be a SCUBA “personal trainer”. I don’t like large classes. I prefer teaching small to private courses. People tend to enjoy the course more and are more attentive in small group settings. Plus, I like getting to know people and making dive buddies.
 
This season we are adding a non-certification personal training course for divers who are looking to hone their skills and not necessarily receive a certification card from it.  Well, Why would you do something like that? We want to be able to offer a training experience that helps you identify your weak points of diving and hone them into shape. It takes the focus off of just getting a cert card and finishing the course. The focus is how you preform diving above and below.
 
This course is designed to personally evaluate the individual diver. The course will cover dive planning, gear set-up and streamlining, in-water skill honing (such as buoyancy control and gas management), reel and smb deployment, situational awareness, post-dive considerations, and much more.
 
Every course is individualized and taught as a 1-one 1 course. The course will last 2 days and will cost $199. The end product is that the diver will be much more comfortable and competent in their diving skills in and out of the water.
 
If this is something that you are interested in, contact us and we will discuss where you are and where you want to be in your diving. 
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Police your Dive gear!

1/14/2017

4 Comments

 
Do you look like an underwater yard sale while diving? Are you losing pieces of gear during your dives? Have you ever had a piece of dangling dive gear entangled? If so, this article will help you get your gear all cleaned up and streamlined. 

The more streamlined you keep your gear and body in the water column, the more efficient and safe you will be. Also, if you keep your gear from dragging around and dangling all over the place you are less likely to damage aquatic life!


Here are some ways to stow your gear that will keep it in the same place each time you dive. This helps develop muscle memory which in turn results in faster response times to deploying gear when needed.
Attaching Flashlights
When divers add flashlights to their kit it is usually tied off to their wrist or dangling around somewhere. With the use of a bolt snap, line, and bungee you can get it out of the way when not in use. Check out the pics below and see how you can adapt these modifications to your own gear.

Before

Hollis sms75 rigging
Some bungee, line and bolt snap.
Hollis sms75 flashlight

After

Hollis sms75 rigging
Attaching Line Cutters
Unless your spearfishing, pumpkin carving, or a few other random activities that I can think of, you probably don't need a dive knife. If you decide to use a knife for your diving activities you can do a lot with some cable ties and your bcd to keep it nice and tidy. Also, the inside of your calf is a pretty good place to stow it with knife straps. Line cutters are a much more efficient tool to use to cut yourself free of entanglement. They are much easier to stow and keep streamlined to your body. Try attaching them to your dive computer to keep them out of the way and easy to get to. Check out the pics below
Shearwater perdix bungee mount
dive computer with line cutter
Attaching Slates and other accessories.
Many divers employ the use of underwater slates for more complex communication underwater. They are normally bulky pieces of gear that dangle all over the place. Instead of buying a big slate, consider a wrist slate. My personal favorite is wet notes that I can stick in my thigh pocket. My drysuit has a thigh pocket on each side. If you don't own a drysuit that is no big deal. We sell glue-on thigh pockets that work nicely on wetsuits. We also sell a pair of shorts that go over your wetsuit that have thigh pockets on it. Thigh pockets are a great addition on how Check out the pics below.
Bad idea
Hollis sms75

Drysuit Pocket
thigh pocket
Better
Underwater Wrist Slate

Pocket Shorts For Wetsuit
scuba shorts with pockets
Wetnotes
Wetnotes scuba

Glue-on Thigh Pocket
Glue on thigh pcoket
 Snaps VS Retractors
I believe that bolt snaps are a much better option than retractors and lanyards in most cases. Bolt snaps are much less bulky and keep gear more streamline. Some divers are intimidated with using a bolt snap and fear dropping gear and losing it. However, just some above water practice deploying and stowing equipment will prove that it is not a problem. Buy good quality stainless steel snaps. Zinc snaps will corrode and the gate will jam or you will be unable to open them just in a few dives in salt water. Even in fresh water the cheaper snaps gate spring will begin to rust and you will have trouble using them. We sell SS snaps that are always available at the dive shop.
With Retractor
Hollis sms75 rigging
With bolt snap
Hollis sms75 rigging
SS bolt snaps
Stainless Steel Bolt Snaps
Octo and Boat Snaps
Try using a small bolt snap with some bungee or large o-ring to clip off your octo to avoid dangling. This works better than most manufactured octo holders. All you have to do it pull the octo off and it will pop away from the bungee with ease.
Best octo holder
best octo holder
Learn a Hand Signal
Below is the hand signal to say, "You good sir, have a dangley". You should use this hand signal to help your dive buddy police their dive gear 
dangley
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