The colder weather is coming and you may be thinking of putting your diving equipment away for the season. You may even be thinking of dragging out that equipment used for the wrong form of water (i.e. skiing). But, wait; Don’t stop diving now! The weather outside is wonderful and the lake water is clearer — I’d like to say clear but this is Texas.
Now is the time to start thinking about taking some continuing diver education courses. Why not get ready for some colder water diving or our California trip by taking a dry suit course? Or, maybe it is time to learn how to field repair your diving equipment. You could even get ready for the 2018 Oceanic Ventures Photography Contest by enrolling in an underwater photography class.
Fall and winter are great times to enroll in classes. You can keep your skills sharp and improve your diving knowledge. Even if you don’t like diving in the colder water, the pool is warm and you can complete your dives in a warm tropical location. Of course, I would not recommend a warm tropical location for your dry suit open water. Think about photography, navigation, equipment field repairs, marine life identification, marine cooking and Principles of Technical Diving.
Call Dive Mom to find out when you can start your program.
Scuba Dive Training
New Scuba Diver Video
The other day, I had an idea to try a new video for the website. My idea was to have a short video to add to our website for new divers to entice them to call or come-by. Since our program is a little different, I thought a video might be a good start along with a new page focused on becoming a scuba diver. Below is the first video I came up with. I have also set-up the new page for a new diver that hopefully provides a little information and will entice them to call. You can find that page here. Please let me know what you think.
Dive Mom Is a Guest on Great Day Houston
Dive Mom, Ann Keibler, was Debra Duncan’s guest on Great Day Houston on Monday talking about scuba diving and scuba dive training. She was joined in the audience by some of Oceanic Venture’s Junior Scuba Divers including Yasmine, Andrew and Ethan as well as their diving mother Ester.
Ann met Debra Duncan at another event, the St Luke’s Foundation’s Friends of Nursing luncheon, sponsored by Neiman Marcus. Oceanic Ventures and the Cayman Island Department of Tourism were sponsors of the raffle at the event which raised money for the nursing program at CHI St Lukes’s hospital. Debra was the Master-of-Ceremonies and introduced the really cool prize. Ann and Tina Hogson from the Cayman Islands Department of Tourism, were on hand to help her understand the prize and to answer any questions about Grand Cayman both from the MC as well as the guests.
If you missed Ann’s appearance, you can replay it here…
Dealing With Accidental Decompression
There is nothing to fear about accidentally going into deco as long as you know what to do when it happens.
Simon is the best-selling author of Scuba Confidential – An Insider’s Guide to Becoming a Better Diver and Scuba Professional – Insights into Scuba Diver Training & Operations. Both books are available from Oceanic Ventures. Simon has also just published a new book for divers-to-be and absolute beginners called Scuba Fundamental – Start Diving the Right Way.
There is a very good reason why instructors tell their students not to go into deco and why dive computer manuals repeat the warning time after time.
Chances are that the cylinder on your back is usually your only air source when you dive. If you run very low on air or if you suffer a rapid loss of air supply, perhaps because of a regulator free flow or a split hose, then the best option you have is to make a slow controlled ascent directly to the surface.
Yes, an alternative option is to share air with an alert, calm and capable diver around who is carrying more air than they need and is both equipped and willing to share it. But you can’t depend that someone like that will be nearby when you need them.
If you stay calm and you are not in deco, that is to say, if your computer is not showing required decompression stops, you will make it safely to the surface. You will probably not be able to make a safety stop on the way up but that is not going to be health threatening. After all, a safety stop on a no-decompression-stops dive is a luxury rather than a necessity.
On the other hand, if you do have required decompression stops, then going straight to the surface and missing those stops is definitely a health risk! That is the main reason why divers are told, “don’t go into deco!”
But Divers Do It All The Time
You may not be surprised to hear that divers accidentally go into deco every day. This is because they are only human, they have fun diving and they tend to get distracted. If it has not yet happened to you, it certainly will, so it is useful to know what to do when it does!
Because they have heard the warning so often, divers tend to panic when they find themselves accidentally in deco. There is no need for anxiety. Going into deco will not hurt you. Going to the surface when you are in deco, however, may well hurt you.
Know how your computer works and what it looks like when you go into deco. Do not be the diver who gets back into the boat moaning about a “broken” computer that is actually functioning perfectly. It is just telling the diver that they should still be underwater waiting until their deco stops clear.
The first thing you notice when you go into deco is that your computer screen suddenly looks different. A new depth reading appears, usually 10ft or 20ft, and a new time display. The depth is your new ceiling; you must not go shallower than this. The time is either your decompression stop time at the ceiling or an indicator of the minimum time it will now take you to reach the surface taking into account both your ascent time and the decompression stop time.
Every brand of computer is different. There is no industry standard. You must know how yours works. I know the manual looks boring but take the time to study it. Trust me, if you see your computer’s deco screen for the first time deep down at 100ft with your brain befuddled by narcosis, you will have no idea what it is saying to you.
Run The Clock Down
So what do you do next? First, look at your pressure gauge. If you still have plenty of air left, relax; you have nothing to be concerned about. Start ascending gradually, keeping an eye on your computer until the deco/ascent time figure stops growing. When the figure starts to drop, continue your dive at that depth but do not go deeper again. Eventually, the deco will clear and you will see your usual no decompression screen display again with plenty of minutes remaining.
Finally, end the dive a little earlier than originally planned to make sure you have plenty of air left to do an extended safety stop of eight or ten minutes before you surface.
Remember
1. Going into deco is nothing to panic about.
2. Know what your computer screen will look like when it happens.
3. Do a long safety stop at the end of every dive where you accidentally go into deco.
Scuba Diving and Narcosis – Diving Under the Influence
Simon is the best-selling author of Scuba Confidential – An Insider’s Guide to Becoming a Better Diver and Scuba Professional – Insights into Scuba Diver Training & Operations. Both books are available now from Oceanic Ventures.
Understanding narcosis, being aware of its effects, and knowing how to manage it are important tools for divers.
When you dive deep, you often see people do strange things under the influence of narcosis. One diver will swim away from his buddy, lost in his own thoughts until he suddenly realizes he is alone in the ocean. Another will keep looking at his computer every few seconds, apparently not registering what it is telling him. A third will stop on a reef wall and stare fixedly at a branch of coral for a good five minutes. Later, he will tell you that he thought the coral was a moray eel and that he was waiting for it to move.
This sort of thing can be funny but there is a serious side to narcosis. The diver who heads off into the blue without his buddies loses the support of the team. The diver who cannot remember what his computer was showing just a few seconds after looking at it is suffering from short-term memory loss and this makes it difficult for him to follow a dive plan.
Narcosis is an integral part of scuba diving. The only way to avoid it is not to dive deep. If you want to dive to 100ft and beyond, then you are just going to have to get used to it!
What is Narcosis?
Air, even oxygen-enriched air like NITROX, is an intoxicating cocktail. Many people will tell you they enjoy the “buzz” of going deep. This “buzz” is mainly due to “anesthetic potential”, something all gases have. In the right quantity, any gas can knock you out. Nitrogen, the major constituent gas in air, has substantial anesthetic potential and, as you dive deeper, the partial pressure of the nitrogen increases, and the depressant effect on your central nervous system becomes greater.
The effects are similar to alcohol and, just as with alcohol, they are dose-related. Narcosis is progressive and increases with time and depth. At 100ft a diver will experience mild symptoms such as euphoria and slow reactions but at 150ft the diver may not be able to function intellectually at all.
There is a widespread misunderstanding of what narcosis is. Many divers claim that they do not suffer from narcosis because they feel more relaxed, comfortable, confident, and capable at depth. However, these are actually the most common symptoms, and, although it might sound like a good thing to feel like that, in fact, this state of mind will lead a diver to take more risks, forget or throw out the dive plan, react to an emergency more slowly and lose track of time.
Managing Narcosis
The good news is that narcosis can be managed.
The first steps are to recognize that it is there and understand what it is doing to you. Then you must train yourself to focus on important issues such as time, depth, and the dive plan and not allow yourself to get distracted.
Exercise mental control over everything you do. Move slowly and deliberately when carrying out a task at depth. You are more likely to get it right if you do something in a sequence of short steps, rather than try and do it quickly.
You can also use memory cues. Technical divers wear wrist slates to remind them of complex dive plans and experienced instructors carry checklists for training dives. They also make debriefing notes as they go because they know that later they will not be able to depend on their memory for the things that happened while they were at depth.
Probably the best defense against narcosis is to rehearse team rescue and self-rescue drills and skills until they become instinctive. Then, in an emergency, you will automatically choose the correct response without thinking about it.
Contributory Factors
A number of factors can aggravate narcosis. These include fatigue, alcohol, stress, cold, and dark water. Anticipating the effect of these additional factors is the key to dealing with them. For instance, use a drysuit in cold water, minimize alcohol intake, and get a good night’s sleep before a deep diving day.
Final Word
Narcosis is something to be understood and managed, rather than feared. There is no law against diving under the influence but proceed towards deep diving gradually. Don’t just go off the deep end straight away!
Ten Tips for Reducing Your Air Consumption While Scuba Diving
A note about the author – Simon is the best-selling author of Scuba Confidential – An Insider’s Guide to Becoming a Better Diver and Scuba Professional – Insights into Scuba Diver Training & Operations. Both books are available now from Oceanic Ventures.
Once you have completed your first Scuba course and begin diving with more experienced divers, one of the first things you may notice is how much longer their air seems to last in comparison to yours. You are always running low before the rest of the group and having to cut short your buddy’s dive.
The people who scuba dive with you will not mind at all. They know you are a new diver and it was not so long ago that they were in a similar situation. However, you probably will mind and you will be looking for ways to breathe more efficiently and make your dives last longer.
Here are 10 tips guaranteed to improve your air consumption and also make you a better scuba diver in many other respects at the same time. Notice that none of these involves using a bigger cylinder!
Tip One – Get in the Mood
Take some quiet time on your own before each dive to relax and focus on what lies ahead. Breathe deeply and find a nice peaceful place in your mind. Put away any negative thoughts concerning other aspects of your life. You are going diving; there is nothing you can do about anything else while you are underwater.
Tip Two – Breathe Properly
Learn to breathe like a scuba diver. Breathe from the diaphragm; push your stomach out to allow your lungs to expand and draw in as much air as possible. Then breathe out long and slow, bringing your stomach in to reduce your lung volume to a minimum. Practice this long, deep, slow breathing cycle until it becomes instinctive. Not only will this help you to use less air, it will help you stay calm and think clearly.
Tip Three – Get Fit
Diving is a sport and the fitter you are, the better you will dive and the less air you will use. Start a programme of aerobic training and increase the level of your training as a dive trip approaches.
Tip Four – Don’t Move
When you are underwater, only move your fins when you need to go somewhere. If you are not going anywhere, keep them still. Tuck your arms in, only use your hands if you need to signal and incline your body like a motorcyclist if you want to change direction or regain your equilibrium.
Tip Five – Remove Weight
Like many new divers, there is a good chance that you are wearing too much weight. A reliable indicator of this is if, after your initial descent, you have to add quite a lot of air to your BCD to keep you off the bottom. What happens next is that, when you start you swim, the air in your BCD lifts your upper torso and the weight around your middle drags your butt and legs down. This gives you the head up, tail down posture of a seahorse. Look at other new divers or ask a friend to take a short video of you, to see what I mean. Moving through water in this position requires much more effort and causes you to use up much more air than if you are horizontal, as you should be.
The trick is to reduce the amount of weight you are carrying. Start by removing one piece and, if you can still make a comfortable initial descent by exhaling fully as you leave the surface, remove another. If, at the end of a dive, you can hang at a depth of 10 to 20 ft. with 750 psi in your cylinder and an empty BCD, you are correctly weighted. Another little thing to remember: if you are wearing a weight-belt and a wetsuit, the belt will loosen and slip down onto your hips a little as the water pressure compresses your suit. So, once you are at depth, take a moment to hitch your weight-belt higher on your waist and tighten it a little. This will lift your legs up and give you a more horizontal posture in the water.
Tip Six – Do an In-Water Check
The whole gearing up, entry and descent process can be awkward and strenuous. For instance, you may be wearing a thick suit on a hot sunny day, there may be a lot of other divers around or the sea might be choppy. A whole host of factors can conspire to undo the positive effects of your pre-dive relaxation and the consequent stress can cause you to go through your air more quickly. So, once you are underwater and the confusion on the surface is behind you, make it a habit to pause briefly and go through a quick in-water check. Take a few seconds to compose yourself, get your slow, deep breathing cycle going, inspect your gear for problems and verify your cylinder pressure (Tip Eight) before heading off to the depths.
Tip Seven – Kick Differently
There are a number of easier ways to fin than the classic wide, full-legged scissor kick you used when you started diving. Learn about alternative techniques like frog kicks and modified flutter kicks. Ask your instructors to show you how or just watch and copy what they do. Using energy-saving fin techniques will reduce your air consumption considerably.
Tip Eight – Know your True Starting Pressure
The cylinder pressure you see when you check your gauge on a sunny boat deck is misleading, as the reading changes with the drop in temperature when you enter the relatively cool water. The underwater reading is your true starting pressure. If you are aware of this you can calculate your airtime (Tip Nine) and this will help you relax. A relaxed diver uses less air.
Tip Nine – Always Know How Much Air You Have
Always know how much air you have left and also have at least a rough idea in your mind of how long it is going to last. This is how you do it.
- As you descend, make a mental note of your air pressure, say 2900 psi
- After five minutes at depth, look again. Maybe you now have 2700 psi.
- This means you have used 200 psi.
- Assuming you are diving the deepest part of your dive first, you now know that you will use a maximum of 200 psi every five minutes.
- If you want to surface with 500 psi, you have 2200 psi left to use.
- So a simple calculation ((2200 / 200) x 5 minutes) tells you that you have AT LEAST 55 minutes of airtime left.
Tip Ten – Keep Calm
If you ever find yourself becoming anxious underwater, the chances are that the reason for this is that you have lost your deep, slow breathing cycle without noticing it. Maybe you have been fighting a current or trying to keep up with a buddy who is swimming at a pace that you are uncomfortable with. As soon as you are aware of your increasing anxiety, stop finning. Calm yourself down by inhaling fully and, most importantly, exhaling fully for a couple of minutes. As you take deeper and gradually less frequent breaths your mind will clear. Check your contents gauge. If you still have plenty of air left, continue with your dive. If your air supply is lower than you expected, ascend to a shallower depth. Remember, the shallower you are the less air you use.
