Simon Pridmore

Scuba Diving – Life on Liveaboards

Have you ever dreamed of living and scuba diving right on top of one of the world’s best dive sites, starting the day by pulling on your wetsuit, slipping into your dive gear and dropping into the clear, warm ocean above a coral reef teeming with fish all waiting to wish you good morning?
This is the dream made real by liveaboard dive boats, which have been multiplying in recent years in response to demand from divers with busy lives who want to make the most of the leisure time they have.
There are options for all budgets, from dormitory accommodation to palatial private cabins, from canteen-style buffets to fine dining. You can share the deck with a couple of dozen other keen divers or scuba in style on an exclusive boutique luxury vessel with personal rinse tanks and dive valets to look after you and your gear. Some liveaboards offer weekend schedules; others extended voyages to really let you get away from it all.

What are the pros and cons of Liveaboard Scuba Diving?

The main advantages are that you get access to more remote and unspoilt places that see comparatively few divers and you can easily dive four or even five times a day.
The disadvantages are that you are living on a boat, which can be uncomfortable if sea conditions become rough. Your food options are limited and nightlife is usually non-existent. If you do not get on with your fellow travelers it is hard to escape but liveaboards are usually very convivial places full of like-minded, outgoing folk.

A Typical Liveaboard Day

You wake early, roused from your sleep by sunrise and the sound of activity. You throw on your swimsuit and a t-shirt and head for the galley for a snack to wake you up and give you energy and hydration for the first plunge of the day.
You greet your companions on the dive deck where your equipment is ready to go. You showed the crew how you like it set up on the first day and they are quick learners. During the trip, your dive gear lives permanently in the space allocated to you. Your wetsuit hangs nearby although you will be diving so frequently it will never get really dry! On some boats you gear up fully on deck and jump straight in; other liveaboards use small boats called tenders to take you back and forth to the sites.
Breakfast follows the first dive and from there the day progresses in a sequence of rest – dive – eat – rest – dive – eat until you fall into bed and are rocked to sleep by the sea.
Every boat has a sunbathing area, shaded deck space and a communal lounge where there might be a Scrabble game going on or someone running through their photos from the last dive. If you want some privacy, you can retreat to your cabin, which on most boats is a shared twin room with bunks or single beds. If you are traveling alone you may find yourself sharing with a stranger, usually of the same sex. This is not necessarily a bad thing. You may find you have made a buddy for life!
There are fresh water showers on deck and usually in the cabins but expect hot water to be in short supply. Think of it as a wonderful surprise if you get some and use it sparingly as you may not be the most popular person on board if you are the only one that got to enjoy it!

Tips for Liveaboard Trips for Scuba Divers

Join a pool session or a local dive. Run an in-water check on your equipment before you go. If you find problems get them fixed and then go back in the water and check everything again before you leave.
Pack light: liveaboard life is very informal. Take a few T-shirts and pairs of shorts, a sarong or two and a sweatshirt for the cool evenings at sea. Don’t bring shoes apart from those you wear to travel; you will go barefoot on board and can use your dive booties for any beach walking.
Be prepared with: –

Multiple surface signalling devices such as a torch, a noisemaker and a tall, brightly coloured safety sausage
A small spares kit containing mask strap, regulator mouthpiece and two fin straps, (as they both tend to break at the same time!)
A personal medical kit containing anti-motion-sickness pills, patches or wristbands; eardrops; antibiotic ointment for coral cuts and hydrocortisone cream for hydroid stings.

Warning: liveaboard diving can be very addictive!

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.

Hidden Scuba Diving Treasures – Muck Diving

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.

You roll off the boat and look down to get a hint of the wonders that await you on this dive but it seems you are in the wrong place. There are no glorious coral formations; in fact there is no reef at all. Instead the seabed seems grey and featureless and the visibility is reduced by the presence of a nearby river mouth.

Sixty minutes later, however, you return to the surface with your mind reeling and your camera’s memory card full of pictures of some of the most incredible marine life you could ever have imagined.

You have just been on an underwater treasure hunt; a game of hide and seek with some very clever opponents. This is muck diving!

The Genesis

While early scuba divers were marveling at the beauty of coral reefs and hanging out in the blue watching for whale sharks and manta rays, a whole universe of amazing creatures were going about their business under the sea completely un-noticed.

How could they have remained undetected for so long? Well, first they were small, second, they had developed the art of concealment to a very high degree and third they lived in places that were not particularly pleasing to the eye. Primarily, however, they remained unseen because nobody was looking for them.

Then a few things happened to bring these little creatures into the limelight.

First, the big fish became fewer in number and harder to find. Second, divers became older and a little lazier and, third, there were significant advances in underwater macro-photography.

Most importantly a few enterprising individuals in Papua New Guinea, Indonesia and Malaysia started looking for marine life in unusual places where nobody had looked before and began to find some absolutely astonishing things.

Muck diving is the quest for these beautiful animals in the sometimes-inhospitable environment where they hide.

Where to Go

New muck diving locations are being discovered all the time but, so far, the world capital is Lembeh Straits on the northeastern tip of Sulawesi in Indonesia. Other locations that also deserve honourable mention include a variety of sites right across northern Bali, Dumaguete in the Philippines, Pulau Mabul off the coast of Malaysian Borneo, Komodo, Ambon and Alor in the Indonesian archipelago and Milne Bay in Papua New Guinea.

Muck Diving Techniques

At first it can appear an impossible task and you will be amazed at how your guides can see things that are almost invisible until you look carefully. Keep trying, however, and with a little experience you will be spotting your own hidden treasures. The thrill of discovery when you find something rare and exotic is hard to beat.

These tips may help: –

Look ahead as well as beneath you
Be alert for movement as you pass.
Follow tracks in the sand
Get as close as you can
Examine everything from several angles
Be patient and take your time
Move slowly
Stay as near to the sand as possible without disturbing it
Use a fin-kick that does not involve downward fin movement so you do not disturb the sand: a gentle frog kick works well

More Spotting Tips

You can also increase your chances of spotting success by knowing where to look, for instance: –

Ornate ghost pipefish hang out among feather stars.
Pipefish and seahorses hide among sea grass.
Baby clown frogfish love rotting wood.
Sea cucumbers host colourful emperor shrimps as well as swimming crabs
Harlequin shrimps feed on sea stars
Urchins are often home to shrimps and baby fish
Fire urchins are where zebra crabs live
Tube anemones often have small harlequin swimming crabs on their trunks
Sea pens shelter porcelain crabs in their fronds

Pointer – OVI Has them in stock

Essential Equipment

An excellent tool that all the top guides use is a stainless steel 30 cm pointer, which you can thrust into the sand to help you balance as you hunt for animals. You can also use it gently to move aside a concealing weed to see more clearly. Attach the pointer with a lanyard to your BCD and tuck it into your harness when you are not using it.

Just Scratching the Surface

Remember, many of the creatures being discovered by muck divers today are new to science. It is exciting to imagine how much more there is to learn and what surprises remain to be discovered by someone with patience, a sharp eye and a pointer.

Scuba Diving – The Black Gasses

Nitrogen is commonly painted as the bogeyman gas for divers, but there are two other gases that can cause scuba divers problems. Carbon dioxide (CO2) and carbon monoxide (CO) are the real black gases of scuba diving.
By Simon Pridmore
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.

The dangers of CO2 in particular have come to attention in sport diving recently with the increasing popularity of rebreather diving, where it has been a factor in many accidents. However, it is important to appreciate that open circuit divers are also at risk. CO2 build up is a major contributor to one thing that, above all else, causes divers to come to harm – panic!
The risk of CO2 poisoning is something that all divers should be aware of but its importance is often understated in basic training manuals, where headaches are commonly given as the only adverse effect. Divers therefore often do not think of it as a threat at all.

How CO2 can affect us all

CO2 is a waste product of the metabolic process and is potentially toxic. Usually, we automatically regulate the level of CO2 in our bodies just by breathing. If there is too much, our brain detects what is happening and causes our breathing rate to increase in order to to flush out the excess.
Divers tend to develop higher-than-normal levels of CO2 during a dive. This is because when we are underwater we do not eliminate enough of the CO2 that our body is producing, especially when we are deep and exerting effort.
This is due to a number of factors, including: –

Water pressure on the chest;

The extra resistance to breathing imposed by the our equipment, and

The increased density of air at depth.

A high level of CO2 in the bloodstream produces a condition called hypercapnia. Hypercapnia does indeed give you a headache but it can also make you confused, dizzy, disorientated, light-headed, short of breath and panicky.

How to Prevent and Combat CO2 Poisoning

The key strategies to deal with the threat posed by hypercapnia are awareness and prevention. Know that it is a risk, anticipate situations where it is likely to occur and avoid such situations. CO2 build up happens mainly when you descend fast, head down, or when you swim hard at depth, perhaps when you are swimming against a strong current or hurrying to get back to the boat because you are low on air.
Because the deeper you go, the more dense your air becomes, working hard on deeper dives carries a greater risk of CO2 build up. So, if you are deep and find yourself fighting a current, change direction and go with the flow. Or ascend to a shallower depth so you are not dealing simultaneously with the twin challenges of both depth and exercise.
If you know beforehand that your dive might involve a long, hard swim at depth, always ensure your regulator is set to give you the least breathing resistance possible. Consider using specialized equipment such as a scooter to help reduce your workload.

Carbon Monoxide

The other black gas is carbon monoxide, which is completely invisible and odorless, but potentially fatal if it is present in your scuba cylinder in even small quantities.

How does it get into the scuba cylinder?

Carbon monoxide usually gets into the cylinder because there is an engine exhaust close to the compressor intake. The source might be a permanent fixture such as the exhaust from the compressor engine itself or a dive boat engine. It could also be something temporary. Perhaps a car was parked with its engine running close to the compressor intake while your cylinder was being filled.

How will you know?

Analyzers are available which can be used to detect the presence of carbon monoxide in a scuba cylinder. They work in much the same way as an oxygen analyzer. Otherwise, you will not know until you start feeling unwell during a dive. The initial symptoms are headache, fatigue, irritability, dizziness and confusion. Carbon monoxide poisoning causes oxygen deprivation that leads to loss of consciousness, cell damage and death. As you probably know, carbon monoxide is a threat in the home as well, for instance, if you run a car engine in a confined space such as a closed garage or if your heating system is poorly maintained or poorly ventilated.

What Can You Do?

If you ever feel unwell during a dive then you should immediately abort the dive and ascend slowly WITH your buddy. Do not just go up on your own in case your situation becomes worse during the ascent. Make yourself positively buoyant at the surface, remove your regulator and take a few long deep breaths. Do NOT resume your dive, even if you start to feel better. Once you are safely back home, let the folk at the dive center that filled your cylinder know what happened, so that they can test the air in your cylinder and check their systems. The problem might have been carbon monoxide. It might have just been something you ate. But they should be told, just in case.

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

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 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!

Scuba Diving – Get Control of your BCD!

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.

As you discovered when you first learned to scuba dive, the letters BCD stand for Buoyancy Control Device. This implies that your BCD is an appliance that controls your buoyancy in the water. It would be nice if that were the case but sadly it is not true. No matter how technologically advanced your BCD is, you are still the one responsible for controlling your buoyancy in the water. Your BCD is just a tool that you can use to help you.

But first you need to get the BCD itself under control!

Buy the right one

Most people buy BCDs that are the wrong size because they try them on in a dive shop while standing up and wearing their normal land-based-life clothes.

Try the BCD on in the shop while wearing your wetsuit and once you have chosen a model, ask to try a sample out in the pool first. Take along the size that fitted you best in the shop and take the next size down with you also. The smaller one is probably the one you will keep.

Your BCD should fit you closely, especially around the shoulders, but not restrict normal movement nor constrict you with the bag full and the straps loosened. It must have enough buoyancy when fully inflated to float you comfortably at the surface with your head clear of the water, but no more.

It is best avoid the bulky, top of the range models. They are usually very buoyant even when not inflated and will require you to wear a lot of extra weight to compensate. An oversized BCD can start moving around on its own under water and be impossible to control!

Know how it works

Spend plenty of time studying your new BCD. Hold it up in front of you horizontally and imagine where the air will be when you are underwater. It will always be in whichever part of your BCD is closest to the surface.

Learn where the controls are. While you are swimming, practice finding your inflator mechanism by touch alone: then, practice using it in different positions. Remember it is not a pump; it will only release air when a) it is above your left shoulder and when b) your left shoulder is the part of your body closest to the water’s surface. Otherwise the air will remain trapped inside no matter how fiercely you depress the button. See how need to turn your body while swimming so that your left shoulder is at the highest point. Usually you can manage this by dipping your right shoulder.

Notice that if you are swimming with your head down and feet up, the air will be close to your butt. Most BCDs have a “tail dump” so you can release air in this position. Make sure you know instinctively if the tail dump is on the right or left.

Learn how to empty your BCD completely. Failure to master this skill can make it difficult for you to descend, cause you to carry too much weight to compensate and, worst of all, place you at risk of an out of control ascent.

Set it up properly

Control your safe second stage (octopus) and your console so that you know where to find them instinctively when you need them and also so that they do not swing around below you and damage that beautiful coral you are swimming over. This means controlling the object at the end of the hose, not just the hose. Clips that retain only the hose still allow the object on the end to swing free below you and turn your accessories into reef-wrecking balls.

Minimize the number of extra bits and pieces you carry on every dive and make sure the essential items things, such as your safety sausage and dive light, are stowed away or attached securely. The two golden rules are:

only one thing in each pocket because if you have several items in the same pocket and pull one thing out, everything else will come out with it: and
attach everything by two points so that,
1. it does not dangle and,
2. if one of the attaching points breaks you do not lose it.