by Phillip Moore
Koh Tao, Thailand

The wise old saying ‘don’t knock it before you’ve tried it’ sprang to my mind as I signed up for a cavern-diving course organised by James Thornton-Allan of Big Blue Tech in Thailand. Cave diving has been described as the most dangerous sport on the planet. So what motivates divers to explore the underworld? Was it just a case of testosterone-fuelled machismo? Or was there some higher purpose? The two-day Cavern course is basically a ‘taster’ for recreational scuba divers interested in cave diving. James explained: “There are three progressive courses, Cavern, Intro Cave and full Cave Diver. The Cavern course is the most popular, although there is about a 50 per cent fall out along the way to Cave Diver.”

I was starting to question my own motives for being on the course, but then again what else would I rather be doing on my birthday? James and Big Blue Tech run all of the courses from Koh Tao Island, in the south east of Thailand. This exotic little island set in the tropical landscape is conveniently located close to some of the best caves and caverns in Thailand. Big Blue Tech  charges around £400 (20,000 THB) for the two-day course, which leads to a TDI-rated cavern-diving qualification. Attendees should be at least 18 years old and hold a minimum of a Advanced Open Water Diver certification with 20 logged dives.

James introduced us to his typical gear layout which included a canoeist’s safety helmet. He explained that the plastic helmets stop divers bashing their heads on overhead rocks, and believe me this is easily done in the pitch black. He said that the helmets were ideal for cave environments because they are light, robust and allow any trapped air to escape. The helmets were also the perfect place to attach dive lights. I hadn’t brought any torches with me, so ended up borrowing two from him .

Over the years, James has adapted his own equipment to suit the harsh conditions. His favourite items are bands of elastic and rubber Snoopy loops. The stretchy elastic bands are used to fix torches to helmets and act as arm straps for securing knives and other equipment. Snoopy loops are strips of rubber tyre inner tube used to secure guidelines and tie-down any loose equipment straps that could get snagged or entangled. Practical training was held at Temple Cave, near the Rachaprabha dam on the outskirts of the Khao Sok National Park. On day one we spent most of the afternoon swimming about in the Chiew Lan Lake focusing on line-laying/recovery and getting used to our new equipment configurations. James also wanted to check us out before going deep inside the cavern. There was quite a strong change in buoyancy going to fresh water, which made untying Snoopy loops while blindfolded a little tricky, but it also highlighted the fact that cave diving is a team effort.

We finished off the day’s lectures at the Prival Raft House, located just a 45 minute longtail drive from Temple Cave. I was looking forward to supping a few pints of Chang beer and celebrate my birthday, but this wasn’t to be – cave diving is a serious business, and by the time James had finished re-emphasising the morning’s presentations, it was past 10pm and time for bed. We would sleep on the floating raft house so at least i wouldn’t have to travel too far for sleep.

We had chosen the perfect time, with clear blue skies and sunshine. But it didn’t really matter to us. Day two of the course is spent deep inside the Nam Lek Cave (which means small water cave because of it’s narrow entrance). James had joked about a long boat ride to the entrance, but I wasn’t sure whether he was being serious. Next morning I realised he was being deadly serious. Nam Lek Cave is an awesome site for taking pictures of monkeys and exploring the far reaches of the park, but having to sit in a loud open top boat for over an hour was difficult on our ears.  At least it was sunny, It would have been a complete nightmare taking this journey in the rain. I had been stuck behind a desk for far too long and was totally unprepared for any intense outdoor activity.

We arrived at the dive site in a shaded area covered by dense jungle and palm trees, i couldn’t resist jumping into the water for a quick swim. It felt like jumping off a sunbed and walking straight into a freezer.

One moment I was hot and sweaty and the next I was chilled to the bone. There was no sound whatsoever, no dripping water or chirping birds, just total stillness. We kitted on the boat at the entrance and then disappeared into the all-consuming blackness with only the natural light of the entrance visible. My watch thermometer only registered 20°C, but James assured me it was definitely 24°C. Either way, it definitely felt cold.  Full length wetsuits and gloves are essential. We took it in turns to lay the guideline and tie off Snoopy loops along the way. Luckily, there were a few rocks and some old tree logs lying on the bottom to use as tie points. Although having the helmet lights meant I had both hands free, it was difficult not to blind my buddies when I looked in their direction. On the way back we had to turn off all our lights and just use the guideline to get out. This is a real mind-blowing scenario. Pitch black with only a slight source of light from the entrance, cocooned in solid rock with no direct access to the surface and just a guide line leading the way to safety – definitely not everyone’s cup of tea.

The cavern itself is a maze of columns, horizontal passageways and different levels. For training purposes we spent all of our time on the upper level at 6m. James said it dropped to around 20m at its deepest point. Underwater visibility averaged 20 metres, but we were all stirring up the bottom with our fins. On a good day it could be more than 30 metres. Our second dive took us in the opposite direction. We came across an old fishing trap which was the only distinctive feature I had seen. James begrudgingly allowed me some time to fire off a few photographs before ending the dive. Photography is not normally allowed during training. By the time I had transported all my kit on to the boat and and travel back to the car park, I was totally knackered, but relieved that I had survived the ordeal/training course in one piece. At least it had been a memorable birthday.

The Cavern course showed me the bare bones of cave-diving ethics and gear requirements. One of my buddies lapped up the course and has already signed up for an Intro Cave. Another buddy really enjoyed himself but won’t be going any further. As for me, I had a great experience and would definitely use some of the training skills that I learnt on future wreck-penetration dives. It’s a shame there had been no time to explore or just get used to being inside the darker sections of the caverns, but this course is designed as a ‘taster’ and you get more of this on the Intro Cave Diver course.

In preparation for high season of technical diving all equipment gets a full service.

Koh Tao, Thailand

Big Blue Tech facilities manager and senior technical instructor Ash Dunn has been furiously servicing all our technical diving equipment in preperation for our high season in starting in september. Diving equipment requires logged, recorded and frequent maintenance by certified technicians using manufacturers service kits.

Big Blue Tech have 12 oxygen decompression regulators, 12 nitrox decompression regulators, 15 apeks regulators with short hose, 15 apeks regulators with long hoses, over 50 cylinders in different formations, 15 wings, 18 back plates, rebreathers and 3 compressors. All of which have exceeded the 6 month standard of service which we uphold as a personal level of inspection.

All of these have been serviced slowly over the past week with the help of interns who have completed their service technician course and other staff members along the way.

Ash is not only a service technician but also a visual inspections, oxygen service, bauer compressor service technician and focused on getting all our equipment in top shape during our slow period as we lead up to holidays in august.

Some regulators and cylinders that are exposed to pure oxygen require special procedures to ensure there’s no reaction between rubber or silicon products inside the parts and the oxygen. The use of an ultrasonic bath was essential to get all the grime off the outside and followed up with steps to eliminate sources of contamination.

If you would like to get involved or learn more about scuba diving service technician courses feel free to contact us and we can offer you training or direct you to authorized providers in your area.

Semi closed drager dolphin rebreather course completed in Thailand

Koh Tao, Thailand

Big Blue Tech celebrates the graduation of Duncan Tyler from his TDI Semi Closed Rebreather course conducted over 2 days with 4 dives on Koh Tao island off the coast of Thailand.

The TDI Drager Dolphin SCR course certifies the student with the ability to purchase this rebreather and dive on it independently.

Enjoy the silent world that Cousteau talked about, dive without the noise of your exhaust bubbles in your ears. Get closer to the fish. Breathe warm moist air – no more dry mouth! No matter how deep you go you consume the same amount of gas – no more lugging 15 litre tanks around for longer dives!

This course is designed to give you an insight into rebreather diving. During the course you will learn about the history of rebreathers, how they work and most importantly, as your life depends on it, the maintenance and care of the unit before and after dives. Once you’ve tried this you won’t want to go back to open circuit scuba! A useful stepping stone for tec divers looking at closed circuit rebreathers.

This was also a great opportunity to test out the new closed circuit rebreather which needed some trim and buoyancy adjustment along with bubble checks.

If you ask the majority of divers to define technical diving you will probably end up with a definition at least partly based on depth.

Koh Tao, Thailand

Although the ability to dive deeper than recreational limits has always been one of the major aspects of technical diving it is by no means the only aspect. Technical diving is about extending your diving and this extension can develop along a number of different dimensions.

One of the biggest advantages to using technical diving techniques is in extending the length of the dive rather than the depth. For example a recreational diver with a Deep Diver specialty is certified to dive to 40m. However, 40m recreational dives don’t make a lot of sense. The no stop limit for 40m is between 8 and 10 minutes depending on the tables you use. If you have spent three hours driving to the coast and another two hours on a boat to get out to a wreck then that is a round trip time of ten hours for a ten minute bottom time. That’s an hour traveling time for every minute on the wreck. Similarly if we add up the cost of the fuel for the drive, cylinder fills for the dive, charter fee for the day, possibly overnight accommodation and all the other costs then it results in a huge cost for each minute spent on the wreck.

Of course that ten minutes also includes the descent time so we often end up spending only five minutes on the wreck itself. If the tide is running or you are dropped on a part of the wreck where there are no interesting features then this can be reduced even further. If we know that we only have a few minutes on the wreck then we tend to rush more and as a result may miss interesting points. The temptation to rush the descent in order to get more time on the wreck combined with the overall time pressure also increases the risk of nitrogen narcosis. Thinking back to my own experience of 40m no stop dives I can remember lots of enthusiasm and excitement before the dive followed by a feeling after-wards that the dive didn’t quite live up to expectations. I always felt that I hadn’t really seen the wreck and had no feel for how it was lying and the structure of the wreck. There was always a feeling that although that dive was a bit of a disappointment the next dive would be better and I would get a better view of the wreck next time. On those dives where we were lucky and had fantastic visibility there was a huge feeling of regret that we couldn’t stay longer on the wreck.

Technical diving and specifically decompression diving offers the possibility of significantly increasing the time you can spend on the wreck with only marginal increases in cost, effort or risk. Once you are properly equipped and trained for decompression diving then the no stop time disappears as a limitation of your diving. If you are prepared to undertake a certain amount of decompression stops on the ascent then you can pass that no stop time and enjoy a significantly increased time on the bottom. For example, if we increase our bottom time from ten minutes to 20 minutes then we in effect more than double our actual time on the wreck as the descent time stays the same. This means that we are getting more than twice as much time on the wreck for the same cost, the same travelling time and almost the same effort. This extra ten minutes will give us much more time to explore the wreck and get a feel for the layout. We can certainly see more of a wreck in a single 20-minute dive than we will in two ten-minute dives. Now the price of this extra time is that we will have to perform decompression stops on the way back to the surface. In this case a 20-minute bottom time will give us 11 minutes of decompression stops. This seems to be well worth the effort. An additional 11 minutes of decompression at the end of the dive doesn’t seem to be an unreasonable cost to pay for the increased time on the bottom. After all getting time on the bottom is why we dive.

As we increase the time on the bottom the amount of decompression also increases. If we do a 30-minute bottom time then we will have to do 30 minutes of decompression on the way back up. While 30 minutes on a wreck is very appealing, 30 minutes of decompression is now starting to become a significant price to pay. For many divers 30 minutes of decompression is a significant amount and they start to think that the benefit to cost relationship is starting to swing too far towards the cost. In addition, as the decompression obligation increases the gas reserves that are required start to increase. However there are additional ways that technical diving techniques can start to help.

The above examples were all worked out assuming that the diver is breathing air. However, by changing our breathing gas we can gain a further advantage. For no stop dives at 40m the advantage of nitrox is minimal. The risk of oxygen toxicity means that we can only use relatively weak nitrox mixtures which have a minimal effect on no stop times. Using EAN28 at 40m increases our no stop time from eight minutes to 12 minutes. Although this is a 50 per cent increase the additional cost of a nitrox fill for four minutes extra on the bottom is often judged to be not worth it. However, for decompression dives the advantage becomes more noticeable. In the example above, a dive to 40m for a bottom time of 30 minutes resulted in 30 minutes of decompression if we are breathing air. On the other hand the same dive, using EAN28 rather than air, gives only 17 minutes of decompression.

Although this is less than the 50 per cent advantage on the no stop dive a saving of 13 minutes is much more noticeable and is often considered to be well worth the cost and effort of using nitrox rather than air. We have already established that we can see more of the wreck in a single 20-minute dive than in two ten-minute dives and this principle is even more applicable for a 30-minute dive. We have the time to properly explore the wreck, to investigate certain areas in detail and even to start to penetrate into the interior of the wreck. We can often swim the length of a wreck and see the bigger picture of the shape, condition and layout of the wreck. It’s not until you start to do longer dives on a 40m wreck that you can even start to get an overall feel for the wreck and really start to get to know it. For wreck researchers this length of bottom time is very valuable in providing time to be able to start identifying features and begin the process of identification.

In addition to using nitrox as our main breathing gas, technical diving techniques also allow us to switch to a second nitrox mix during the decompression in order to further optimise our decompression. Decompression stops allow time for dissolved nitrogen to come out of the body. We cannot ascend any higher until a certain amount of nitrogen has been allowed to escape. If we do ascend before the required amount of nitrogen has been allowed to escape then it will form bubbles which is the cause of decompression sickness (DCI). When we switch to a second nitrox mixture with a higher percentage of oxygen, and by implication a lower percentage of nitrogen, the nitrogen dissolved in our body comes out faster and so we don’t need to wait as long before we can move up in the water. This is why the technique is known as accelerated decompression, although some people prefer the term optimised decompression.

By using EAN50 as a decompression gas we can reduce our decompression to 13 minutes and by using EAN80 or even 100 per cent oxygen we can reduce it to just nine minutes. Alternatively we could further increase our bottom time to 35 or even 40 minutes until we reached the maximum amount of decompression time we were happy to do. Of course you don’t get anything for free and using this technique introduces a number of other considerations that the diver will need to take into account. In particular, much more detailed gas planning and the risk of oxygen toxicity must be considered. This is why specialised training is required in order to make use of these specific tools. In particular the decompression times and dive practices contained in these examples should not be taken as correct and are only provided for illustration (that should keep the lawyers happy).

It should now be starting to become clear why some qualifications limit the time as well as the depth of the dive. There is only so much trouble you can get into on a no stop dive whereas there is more potential for problems on a decompression dive. Recreational dive qualifications limit divers to no stop times to limit the risks they are exposed to. Some other courses limit the diver to 15 minutes of decompression and are sometimes referred to as advanced recreational courses rather than full technical courses. As the diver progresses to full technical courses then the skills they will learn and the planning techniques they will use means that there is no limit on the amount of decompression a diver can carry out as long as they stay within the safe limits of gas availability, CNS and all other planning variables. In many cases it will be the diver’s own personal limits rather than any external factor that determines the maximum amount of decompression they want to do.

The skills contained within technical diving courses that allow a diver to extend the time they can spend on the wreck are also a way to extend your diving. Many people undertake this training so that they can be safer and more skilled at the depths they are currently diving at rather than to progress any deeper. The skills required for technical diving can also make you a significantly better recreational diver. Having better buoyancy control, awareness of your situation and of your buddy will all help to make you a better diver. Together with better self rescue and buddy rescue skills they will also make you a safer diver no matter what depth you are at.

One of the things that distinguish technical divers from recreational divers is the amount of equipment and, in particular, the number of cylinders that are carried.

Koh Tao, Thailand

A recreational diver might carry a single cylinder and for some dives may add on a pony cylinder for redundancy. Technical divers will use either a twinset or a rebreather but in addition will carry a number of stage cylinders. They are usually clipped onto the diver’s side.

The term ‘stage cylinder’ is used as a generic term to describe these cylinders but in fact there are a number of different uses for which we use these cylinders and their names reflect the purpose that the cylinder is serving at the time. Another term that is used is a ‘side-slung’ or just ‘sling’ cylinder. This comes from the fact that the cylinder is usually mounted or slung on the side of the diver. The term ‘stage’ cylinder comes from cave diving, where divers would stage or drop cylinders at various points in the cave for use on the way out. So, for example, a cave diver might swim in breathing from his stage cylinder and when he has breathed a third of it he would remove it and clip it to the guideline. He would then continue using his twinset until that was also a third used. At this point he would turn around and start swimming back out. Using this method he should get back to his stage cylinder with a third still left in his twinset. At this point he would pick up his stage cylinder, which still has two thirds left and breathe that for the rest of the exit. Using this approach he will exit the cave with a third reserve in his twinset and a third reserve in his stage. This approach works as the cave diver knows that he will be exiting along the same line that he entered and so will always be returning to his stage cylinders.

This approach is normal in cave diving but is much less common with wreck penetration diving. The two reasons for this are that firstly the penetration distances in wreck dives are not usually as long as with cave dives. Secondly the number of exits may mean that we exit the wreck at a different point to the one we entered and so we may not always get back to our stages. As a result it is much less common to stage gas on wreck penetration dives. The exception to this is that some divers remove their stages before entering a narrow restriction or hole. This allows them to get into more restricted areas but should be used with caution as if they cannot get back out or have to exit in another area then they cannot easily get back to their staged gas. For this reason it is recommended that wreck penetration divers do not stage their cylinders. The most common use of stage cylinders for wreck dives or any other open sea dives is to carry a decompression gas. When used in this way stage cylinders are usually referred to as deco cylinders. In this case they will contain a rich nitrox mix which is used to accelerate or reduce the diver’s decompression obligation.

Wreck divers may also carry a stage cylinder containing the same gas as in their twinset. This is known as bottom gas as it is breathed on the bottom rather than deco gas, which is breathed on the ascent and decompression stops. A bottom gas stage might be used to extend the bottom time of the dive if the twinset doesn’t contain sufficient gas to allow a safe reserve. It can also be used where getting subsequent fills may be difficult. In this case the diver may plan to use their bottom gas stage and a proportion of their twinset on one day and then use an additional pre-prepared bottom gas stage and the rest of their twinset for the next day. In this way they can get two dives from a single twinset and two stages of bottom gas.

The last use of stage cylinders is as a bailout stage for rebreather divers. A rebreather diver would normally plan to use their rebreather for the duration of the dive. However, if there is a problem with the rebreather then the diver would ‘bailout’ to the stage cylinders he is carrying. In this case the diver would need a bailout cylinder that they could start using at the maximum depth and would then need sufficient bailout to get to the surface completing all their decompression. Unlike the open-circuit diver the rebreather diver will not use their stages unless there is an emergency but will still need to carry them.

One of the biggest dangers facing the technical diver is breathing from the wrong cylinder and, in particular, breathing a rich nitrox mix at depth which will almost certainly lead to oxygen toxicity. For this reason it is essential that all stage cylinders are analysed before use and labelled accordingly. The maximum depth at which the gas can be breathed, known as the maximum operating depth or MOD, should be clearly marked on the cylinder in a position where the divers buddy can clearly see it. The contents and date analysed should also be marked but this can be smaller and less obvious. Every time that the diver switches to a stage cylinder he must get his buddy to check that the gas is safe to breathe at that depth. This is why the depth is marked rather than the percentage of oxygen in the mixture. It is much easier to check your depth rather than look at a percentage and work out the maximum safe depth in your head.

The main choices when using a stage cylinder are the composition of the cylinder and the size. Stages can very from five litres all the way up to 12 litres. The right choice of size will depend on a number of factors. The larger the capacity the larger the physical dimension and weight of the cylinder, and so the diver needs to consider what size cylinder they are happy to carry, both on the surface and on the bottom. The choice of decompression gas will also have an impact on the size of cylinder required. For example, if a diver uses 50 per cent for their decompression gas then they will switch to it at 21m and breathe from this cylinder for the majority of their decompression, as a result they will need a large volume of decompression gas and will need a larger cylinder to carry all of that gas. However, if the same diver uses 100 per cent oxygen as their decompression gas they will not switch until they get to 6m and, as a result, will use much less decompression gas and so can carry a smaller decompression cylinder. In the UK seven-litre stages are the most common, but in recent years with the increasing popularity of using 50 per cent as a decompression gas, it has become more common to see larger decompression stages. Although most UK cylinders are measured in terms of litres, some cylinders are now measured in cubic foot. 40 cubic foot and 80 cubic foot cylinders are becoming more common. 40 cf is approximately equal to a five-and-a-half-litre cylinder with 80cf cylinders containing approximately 11 litres. For divers using 50 per cent as a deco gas and requiring more volume of decompression gas, an 80 cf cylinder is an attractive option.

With a single stage cylinder it is common to wear this on the left-hand side. Typically the top of the stage cylinder is clipped to the D-ring on the left hand shoulder with the bottom clipped to a waist D-ring on the left-hand hip. However, when using multiple stages, either because of using multiple decompression gases, using a bottom gas stage together with a decompression stage or with multiple bailout cylinders while diving a rebreather, we need to consider where we will carry the cylinder. One option is to carry two or more cylinders all on the left-hand side. The other option is to clip one cylinder on the left and one on the right. In this case the leanest mix, the one with the lowest percentage of oxygen, is worn on the left-hand side and the richest mix, with the highest percentage of oxygen, is worn on the right-hand side. For this reason this approach is known as lean left – rich right. The best option, all stages left or lean left – rich right, will depend on a number of factors. For example if the diver is using steel stages, then the fact that they will be very negatively buoyant will make wearing them both on the left very uncomfortable as they will pull the diver over to that side. In this case wearing them lean left – rich right will be much more balanced. However if the diver is using aluminium stages then having them on the same side is perfectly feasible and can be more comfortable.

As the number of stages increases the decisions get more complicated. With three stages it is still possible to wear them all on the left hand side whereas with lean left – rich right you will need to have two stages on one side and one on the other. With four stages it is no longer possible to have them all on the same side although it is possible to have two on the left and two on the right. Beyond this additional solutions have to be used, either stages staged on the shot line, support divers carrying additional stages for use on the later parts of the decompression or the use of a leash to attach additional cylinders behind the diver. Neither of these options are desirable for open water diving. Using stages on the shot line or support divers mean that the diver is no longer self sufficient and adds significantly to the complexity and organisation required for the dive. In addition there is always the risk that the diver will have to ascend away from the shotline. Multiple cylinders can be carried by the diver if they use a leash; this is a loop of rope with a boltsnap attached. Multiple stages can be attached to the leash and then the leash clipped onto the hip D-ring so that the stages trail behind the diver. This approach will only work with aluminium stages as steel stages will be negative and will not sit comfortably on the leash. In addition only certain types of aluminium cylinder, and even then only at certain pressures, will sit comfortably. The use of a leash adds an additional level of complexity and risk to open water wreck dives. For these reasons the majority of technical divers do not use more than three or four stages.

The use of rebreathers has become very common amongst technical divers.

Koh Tao, Thailand

In this article we will look at the advantages of a rebreather and some of the reasons why people may want to switch to diving one. We will also look at the types of people who are suited to rebreather diving and those who aren’t.

One of the biggest factors that comes into the decision to switch to a rebreather is costs. This has two aspects: the costs of the rebreather, including buying and maintaining it, set against the cost of open circuit diving. One of the biggest disadvantages of open circuit trimix diving is the cost of the gas. A twinset of trimix can cost anything from £30 for a relatively weak mix for use in 40m to over £100 for a mix suitable for diving deeper than 100m. This makes each trimix dive an expensive proposition. On the other hand a rebreather uses much smaller cylinders because the gas is reused rather than wasted; as a result we use much less and the gas costs are much lower.

We might only be spending £10-£20 for the same mixtures discussed above. As a result there is a significant gas saving when compared to open circuit diving. This can look very attractive when you are spending considerable amounts on each open circuit fill. However this must be set against the costs of the rebreather. Depending on the model a rebreather is likely to cost between £4-8,000. If you go for an older second-hand model then you might get one for less than this. In addition to the initial cost of the rebreather you will need to factor in training on the rebreather which is likely to add on another £1,000.

In addition there will undoubtedly be additional costs to add on extra equipment to the basic rebreather. As a result it is not uncommon for the initial start up costs on a rebreather to be between £6-10,000. Obviously you will need to do a lot of trimix diving in order to save enough to justify this initial outlay. The vast amount of technical divers do not do enough diving to clearly justify buying a rebreather based on savings in gas costs. Unless you are doing 20 or more trimix dives a year then it is not cost effective. If you also do a significant amount of recreational diving then each dive may actually cost you more on a rebreather.

On open circuit you may only need to pay for an air fill but on even the shallowest dive you will still need to use pure O2 in one of the cylinders and use carbon dioxide absorbent in the rebreather. The annual replacement of the three O2 sensors and handset batteries also needs to be taken into account. This means a shallow recreational dive may only cost £5 for an open circuit diver but £10-£15 for a rebreather diver. Unless you are doing significant numbers of deep trimix dives a year with little or no recreational diving then the gas savings from using a rebreather will not outweigh the initial start up costs. However there are still a number of other reasons why a rebreather is an attractive option.

Every time we breathe in we only use a small proportion of the gas we inhaled, the rest is breathed out. On open circuit this is exhaled into the water and lost. However on a rebreather the exhaled gas is fed back through the rebreather, carbon dioxide is removed and the oxygen we used up is replaced. As such it makes much more effective use of the gas we have and we don’t need to carry anywhere near as much gas. As we have already seen this makes each fill much cheaper. It also has a number of other advantages. The amount of oxygen the body uses in each breath is roughly the same independent of depth.

This means that we use the same amount of oxygen at 100m as we would at 10m and so our oxygen cylinder will last the same amount of time at 100m as at 10m. On open circuit we breathe much more at depth due to the effect of pressure and so as we go deeper and deeper we have to take larger and larger cylinders. Despite taking these large cylinders they will still be used up very quickly and so the amount of available gas becomes the most critical part of dive planning. On a rebreather our gas supply is used up at the same rate irrespective of depth and so the amount of gas we are carrying is no longer the limiting factor. Instead the critical factors become the amount of decompression we are incurring, the duration of our carbon dioxide absorbent and our risk of oxygen toxicity.

Of course this assumes that the rebreather will always work as intended. Just in case there are any problems with the rebreather we also need to carry open circuit gas to get us safely to the surface. In this case we would need a bailout cylinder that we could start using at the maximum depth and would then need sufficient bailout to get to the surface completing all our decompression. Unlike the open circuit diver the rebreather diver will not use their stages unless there is an emergency but will still need to carry them. The fact that we are only using smaller cylinders makes the logistics of filling much easier. The volumes of gas needed are much smaller when filling a 3L cylinder rather than twin 12s and so it becomes feasible to take enough gas with you for even a week’s diving.

This contrasts with the situation when using open circuit where significant volumes of helium and oxygen will be required as the majority will be breathed out and wasted. This can make a big difference if you don’t have a local dive shop that can fill trimix. If you have to drive 50 miles there and back to drop off a twinset for a trimix fill and then do the same thing next day to pick it up then the logistics of this can be significant. If you are diving somewhere without easy access to a dive centre that can fill trimix the ability to take your own gas simplifies the planning and logistics.

Even if you wont save money and don’t need a rebreather for logistic reasons there are still other reasons to switch. Diving is a hobby and so doesn’t always have to be justified on cost reasons. The cheapest option is not to dive but most of us don’t consider this a possibility. In the same way that some people spend their money on motorbikes, horses, home cinemas, model helicopters or any other hobby there is no reason why someone shouldn’t spend their money on a rebreather just because they want one. Other people may switch to a rebreather to challenge themselves to learn something new.

There are a number of reasons why many divers want to switch to a rebreather. However, the risks of rebreather diving mean there are some people who are better suited to rebreather diving than others. Rebreathers are significantly more complicated pieces of equipment than an open circuit scuba set. While rebreathers do not require a huge amount of effort they do require more care and maintenance than open circuit. For divers that throw their kit into the back of the car or into the garage and then don’t look at it until the next dive this can cause a problem. This type of person is not really suited to rebreather diving unless they can discipline themselves to ensure they maintain the rebreather.

On the other hand there are many divers who enjoy cleaning and maintaining their equipment almost as much as the dive itself. They get pleasure from adjusting the kit until it is just right and it is viewed as part of the hobby rather than an added chore they must do. This type of person is ideally suited to rebreather diving. Do you have the right mindset? In addition to cleaning and maintenance rebreathers require discipline. There is a certain mindset that is required to ensure that the unit is assembled correctly each time and that all of the pre-dive checks are rigorously followed. Most rebreather accidents are caused by the divers not following the correct procedure. This includes not diving the unit if there is any problem with.

Many divers become complacent and will dive with known problems with their rebreather. They are confident that they can overcome the problem and in the majority of cases they manage to deal with the known problem. However if there is any problem during the dive the impact of the initial problem can be significantly increased by subsequent problems. It requires a significant level of discipline to call a dive for what might appear to be a minor problem but becoming complacent about these failures is one of the most common causes of accidents. During the dive the diver must constantly monitor the unit to ensure it is operating correctly. This is summed up by the golden rule of rebreather diving ‘Always know your partial pressure’.

It doesn’t matter if the diver is at 10m or 100m the level of monitoring is the same and so a 10m dive must be approached with the same mindset as a 100m dive. As such there is no such thing as a casual rebreather dive. Not all divers have the mindset to adjust to rebreather diving but without this mindset they should not consider rebreather diving.

In order to be a safe rebreather diver there are a number of skills that need to be mastered over and above the basic open circuit skills. Some of these are related to the normal operation of the rebreather and some are related to emergency situations. Like any skill it takes practice to master these skills and practice to maintain them.

When moving from open circuit to a rebreather there are skills, like buoyancy control, which must be re-learnt. This takes time and effort. For an experienced diver this means the frustrating process of going back to basics and building up their experience. Unless you are prepared to put in the time to master the basic skills you will always be diving on a base of weak rebreather skills, even if you were previously a very experienced open circuit diver. These skills also need to be practiced regularly in order to ensure that they are maintained. This means that it is essential to dive a rebreather regularly in order to maintain the appropriate skill levels.

For some people a rebreather is a desirable and in some cases an essential way to progress their diving. For others the advantages do not necessarily outweigh the disadvantages. For this reason it is a personal decision and not one to be taken lightly. You must decide whether there is a good reason to dive a rebreather and then whether you have the right mindset to be able to dive it safely. Like many things the correct decision will vary between individuals.

Technical diving is dominating the scuba scene.

Koh Tao, Thailand

It can’t have escaped your notice that technical diving seems to have become very popular.The fact that one of the major UK diving magazines now contains a monthly article about technical diving as well as other regular articles about different aspects of technical diving is just another example of how this once-forbidden aspect of diving has become mainstream.

We can see just how popular technical diving has become if we consider that Technical Diving International (TDI) carried out a survey in 1994 where only one person out of every 100 said that they had taken a technical diving course or were intending to take one in the following year. When a similar survey was carried out in 2008, this had changed to one person in four saying that they had taken a technical diving course or were intending to do so in the following year.

When the term ‘technical diving’ was coined in 1991 by the magazine aquaCORPS, it was considered as being completely different from recreational diving. The main technical diving agencies, such as TDI and IANTD, were formed as a way of providing technical diving training to those divers that were interested in the topic. However, most of the recreational diving agencies condemned technical diving to the extent that in 1992, any technical agency or manufacturer that supported the use of nitrox was banned from DEMA, the largest US diving show.

The reason for this was that the recreational diving agencies considered nitrox to be too dangerous for use by recreational divers. Of course, this view was driven by a lack of knowledge and a fear of anything new. Today, all of the recreational agencies encourage the use of nitrox and have all introduced their own nitrox programmes.

The wider availability of equipment suitable for technical diving has also helped to encourage its popularity. The equipment used for technical diving is quite different to that used in recreational diving. At the beginning it was very difficult for divers to find equipment that was suitable. Many of the early technical divers had to resort to making or modifying their own equipment. This obviously limited the number of people who had the skills and inclination to follow this route. Many of the well-known technical diving equipment companies started off with the owner making a prototype for his own use in his garage and then being asked to make more for his dive buddies. Unless you had the skills to make the equipment yourself, or knew someone who knew someone, it was very difficult to find suitable equipment. However, these days many of the major equipment manufacturers offer a technical equipment range and specialised technical diving equipment is easily available. This means that it is now relatively easy to buy wings, backplates, regulators, canister torches, reels and sophisticated multi-gas computers from your local dive shop, or just order it online and have it delivered to your door.

The wider availability of information has helped to popularise technical diving. The two main developments that allowed information on technical diving onto a wider stage were the publication of the aquaCORPS magazine in the 1990s and the development of the internet. The internet allowed communication between technical divers and provided a means for distributing information on the subject to the rest of the diving community. Rather than isolated pockets of technical divers each doing their own thing, the internet allowed us to develop a consensus on the best options for equipment configuration and diving procedures and to avoid re-inventing the wheel.

These days the internet is an almost-essential tool for any aspiring technical diver. There is a huge amount of information available on almost every aspect of technical diving.

Diving forums in particular can provide a fantastic source of knowledge and advice on technical diving. There are a number of dedicated technical diving forums, and recreationally focused forums will at least have a technical diving section. They are without doubt the easiest and quickest way for a new technical diver to pick up a large amount of good information. Diving forums do, however, have their disadvantages which those interested in technical diving should be wary about. Information on a diving forum may not always be accurate. You should always treat this information with caution. There are a number of reasons why this information may not be as reliable as it seems. Firstly, there are a number of diving urban myths that are continually repeated on internet forums. The fact that they are continually repeated gives weight to these stories or opinions, but that doesn’t stop them from being incorrect or misleading. In some cases, these myths may just be misleading, but in other cases they are downright dangerous.

Any sport or activity will see progress over time and diving is no exception. As a result the popularity of technical diving can be seen as just the natural progression of the activity. It is human nature to want to improve, push yourself or progress your skills and abilities. Human nature also encourages a desire to do things that few other people have done, or visit places that few others have seen. It is this spirit of exploration that has also contributed to the development of this aspect of the sport. Many technical divers progress their diving as a way of achieving a specific goal, which is why technical diving is often associated with wreck or cave diving. In these cases the techniques used are just a tool to find unknown wrecks or explore uncharted caves. For me technical diving is just a tool that I need to use if I want to dive the type of wrecks I enjoy diving. I have often said that if all the wrecks of the world were in less than 30m of water, then I would never have gotten involved in technical diving. While there are still unexplored wrecks in less then 30m, there are far more wrecks that lay much deeper than this, so I need to use different tools and techniques in order to dive them.

Diving magazine stories of divers finding lost wrecks, identifying historic wrecks or piecing together parts of a historical puzzle are always fascinating to read. There are few other areas where someone carrying out their hobby can have such a big impact on identifying major pieces of history.  These have provided a strong incentive for divers to progress into technical diving in order explore these historic sites. Books such as The Last Dive, Deep Descent and Shadow Divers have further popularised technical diving and raised the profile, not just within the diving world, but also in general, and if the anticipated movie based on the latter book comes to the screen then it will undoubtedly generate further interest in technical diving.

One of the other reasons why it has become much more common for recreational divers to undertake technical diving courses is a widespread perception that these courses are a way to improve general diving skills and become a significantly safer diver whatever type of diving you do. Due to the increased potential risks the level of buoyancy control, comfort in the water, problem-solving abilities and general diving skills required to undertake technical diving is significantly higher than for recreational diving. As a result recreational divers, even many recreational diving instructors, see the skills displayed by technical divers and want to reach that same level of skill and control. “I want to be able to do that” or “I want to look like that” are common phrases I hear when I ask people about their motivation for taking technical courses. They may not want to use trimix or dive beyond 50m, but they do want to be safer and more confident when diving in the 30-40m range or when doing some decompression. As a result the increase in technical training courses has led to an increase in the use of technical diving equipment and techniques, and so many of the techniques that were once restricted to technical diving have found their way into mainstream recreational diving.

In the last five to ten years technical diving has moved from being considered as heresy by the established recreational diving community to being part of the mainstream diving industry. In the past, diving deeper than 40m, decompression diving and using gas mixtures other than air were considered so revolutionary that many of these practices were considered unacceptably dangerous and banned by some agencies. This position has softened considerably with most agencies being much more welcoming of technical diving techniques. Many recreational agencies have even gone further and rather than outright banning of technical diving have even started to introduce their own technical diving courses. Clearly this is because they see there is an increasing interest in technical diving, however this also serves to further legitimise this type of diving, which can only make it more popular in the future.

Although technical diving has become mainstream and recreational agencies have started to introduce their own courses, there are still important differences between recreational and technical diving. In the last few years the recreational agencies have tried to make diving as accessible as possible to the majority of people. Initial training focuses only on the essential skills that are required to get people diving and emphasise that diving is safe and fun. For the majority of diving this is absolutely true, however technical diving introduces risks that are not present in recreational diving. The introduction of additional depth, alternative gas mixes, decompression, multiple cylinders, etc, adds risks that are not present on a typical recreational dive. As a result technical training takes a very different form. It emphasises the risks involved and covers a much-deeper understanding of some of the concepts involved, which means the type of approach required for good technical instruction is still subtly different to that required for good recreational instruction.

Plastic bags are killing our reefs and it’s inhabitants and it’s time we all made an effort.

Koh Tao, Thailand

Big Blue Conservation has recently released it’s ecological answer to the plastic bag by making canvas beach bags from recycled material and offering them to tourists for 3 dollars.

Half of the proceeds of the bag sales will go towards our own eco fund which is then returned into the preservation of our underwater environment around Koh Tao.

Our bags feature a thick cotton-canvas blend which makes the bag sturdy, reusable but at the same time light and easy to carry.

Big Blue Conservation provides the ideal solution to the “Empire Strikes Bags” campaign. Our eco-friendly  cotton products are designed to be used again and again. They carry a positive environmental message about our brand. And – because our bags are printed with your logo – they’ll promote awareness of our school and the effort us Koh Tao-ians put into eco conservation.

If you’re on Koh Tao you can come get your very own for only 100 baht!

Study, Research, Biology are all part of the underwater study tech program.

Koh Tao, Thailand

Big Blue Tech, in cooperation with Big Blue Conservation releases a new program to give marine biology or people interested in scientific diving the training and tools to conduct their studys or research safely.

While a lot of underwater impact and research can be done in shallow water up to 30m on normal conventional recreational scuba there is a growing demand for deep water research on coral and marine ecosystems in the 50m range where extended time at the depth is needed.

According to Jen Mathews who graduated from Bath University with a Bsc in Biology there is a huge gap of people who are already divers and want to conduct professional level surveys and research but are limited by the confines of recreational scuba with both time, logistics and gas supply.

Big Blue Tech plan to amalgamate the SDI Solo Diver, SDI Research Diver, SDI Full Face Mask Diver , TDI Decompression Procedures Diver and SDI Marine Eco Systems Awareness into one package which will be conducted by both the director of Big Blue Tech and Big Blue Conservation.

British Suba Aqua Club Thailand awards the title of Open Water Scuba Instructor to a lucky student.

Koh Tao, Thailand

Big Blue Tech celebrates the graduation of Colin Tompson from his BSAC Instructor course conducted over a period of 2 weeks on Koh Tao Island off the coast of Thailand by BSAC Advanced Instructor James Thornton-Allan and examined by BSAC National Instructor Les Skelton.

In addition to his training course and instructor exam Colin also had the benefit to assist on a BSAC Ocean Diver and BSAC Sports diver course before taking his TIE (Theory Instructor Examination) and PIE (Practical Instructor Examination) which he passed successfully.

Colin had previously been working for 2 years as a full time divemaster at Big Blue Diving and decided it was time to join the dark side and by becoming a certified scuba diving instructor.

Big Blue Diving is a BSAC School of excellence meaning it offers the top level of training up to the prestigious Advanced Instructor rating.

Technical Diving school adds the worlds most popular closed circuit rebreather to its collection.

Koh Tao, Thailand

Big Blue Tech recently aquired a new rebreather to it’s collection to provide support to it’s european customers and training opportunities through the BSAC and TDI system of education.

The rebreather is a the AP Inspiration Classic which has sold more units than any other closed circuit rebreather in the world. The Inspiration Classic was the first production rebreather and conctinues to win awards from many diving agencies and magazines.

This also allows Big Blue Tech to provide three models for training of rebreathers with the Drager Dolphin and ISC Megaladon and now Inspiration Classic as options.

With 3 litre cylinders, easy maintenance and simple preparation – the Inspiration brought the benefits of optimal gas consumption and gas mix at all depths to the forefront of diving.

Quickly becoming the choice of expedition divers, film makers and sports divers alike, ranging from beach diving to RIB diving. right up to 100m expedition dives.

To achieve CE certification; the first (and only) CCR to feature dual independent oxygen controllers (Patented), the CCR to set the standard in PO2 control accuracy and scrubber duration; the first to achieve minimal breathing resistance in all diver positions and attitudes, the first mass produced and affordable CCR on the market.

The first to achieve worldwide distributorship with all that entails, including the development of the first unit-specific training courses by the major training agencies; and not least, the innumerable individual firsts that have been achieved by the many thousands of INSPIRATION CCR divers in the world today – from the discovery of virgin wrecks to personal depth and exploration records.

Entry level scuba divers choose BSAC as their certification during their holiday.

Koh Tao, Thailand

Big Blue Diving instructors Yvonne Fries and Hele Artal recently completed a BSAC Ocean Diver course conducted over 3 days on Kok Tao Island off the coast of Thailand. This was the first BSAC Ocean Diver Course conducted by the diving school which followed a successful cross-over program a few days earlier.

The Instructors were thrilled with the differences in theory and commented that they were allowed to teach what really matters in diving and not so much “fluff and sales”. This was also combined with skills that were based on repitition ensuring that the essential foundation skills were mastered before progression of depth could be achieved.

Looking back on the course the Instructors, who are also technical diving instructors, described the course as a challenge that unless the instructor is passionate about teaching divers then it wouldn’t be the course for everyone.

As for the 7 students, they loved their course but without anything to compare it to who knows. Several decided to continue their education and progress on to the BSAC Sports diver course as they found the course work to be challenging and gave them a sense of working for their certification.

The BSAC diving programs reflects diving in realistic conditions ensuring that once the student has completed the course, that they can dive these conditions with safety and enjoyment.

Learning to scuba dive with the BSAC is easy. BSAC adopts a progressive teaching method; breaking down the dive skills into small manageable steps making it very easy for the student to reach the required standard of competence. The theory knowledge is also very easy to understand by using effective teaching aids and issuing you with a comprehensive support materials and student pack.

Theory knowledge lessons are conducted by your Instructor who will use simple small manageable steps. Using simple and understandable terminology makes the theory lessons easy to grasp. On the open water dives; again we use progressive training building-up your open experience and depth experience dives, gradually.

Our BSAC Instructors have been trained to high standards and are highly experience people, Yvonne Fries is a triple certification instructor and won the SSI Most Certifications Issued Award, Helen Artal is also a triple certification instructor and is also one of the first female SSI Technical Diving Instructors in the world.

Big Blue Diving will continue to offer BSAC programs along side their PADI and SSI ones giving our customers more options and choices to chart their diving hobby. But be forwarned it’s not a certification gained easily but when you get your card it’s well worth the effort!

New technical diving computer promotion for trimix and rebreather divers.

Koh Tao, Thailand

Vr Technology the British manufacturer of the VR3 Computer, Sentinel Rebreather, Ouroboros Rebreather and the VRx Computer have released a ecologically friendly promotion to recycle and trade in your old model for a brand new one at a fraction of the price.

Big Blue Tech, a technical diving school in Thailand took advantage of this program when one of their old Monochrome VR3 computers was damaged and needed to be fixed, after discussing the repair options of around 200 pounds (400$) it was decided that getting a brand new one for only a few hundred pounds more was wiser and would give us a better product in the long run.

Vr Technology provides the option of either the VRX Computer or the VR3 HD computer. We decided to go with the VR3 HD computer. Both options featured the full unlocked algorithms,closed circuit trimix and colour without any extra costs, this was essential because many of the features in our old VR3 were used daily.

This program was made possible with the support of the UK W.E.E.E (Waste Electrical and Electronic Equipment) scheme which provides funding and support to companies who dispose of electronic devices in a responsible way.

We’re big supporters of ecological developments, we’re an award winning ecological diving school and resort, which is why it’s great to see companies in the technical diving support field taking notice of responsibility to our environment as well.

The stress on your mind, body and soul from deep ocean diving can be eased with the proper level of fitness.

All sports today benefit from 
physical training; this is especially 
applicable to technical diving. You don’t have to be an anatomy chart or a body builder, but being in better condition does help you handle the stress of the extreme sport to be a more efficient and confident technical diver.

When recreational diving a diver uses one tank but on some of the dives performed technically up to six could be required; different tanks with different gases. A much more cumbersome weight to carry whilst on the boat, particularly when it’s time to attempt standing up!. Once a technical diver enters the water they will normally add a couple more tanks for decompression.

All of these extra tanks and equipment take up more space causing the diver to use more energy. So streamlining your equipment is very important. Your gear should be close to your body to help reduce drag, this is the same scenario as with racing cars. The less drag you have the more efficient the vehicle making it faster. Along with being streamlined you need to ensure that you are able to access everything quickly, just in case of an emergency.

The more energy a diver uses underwater results in a the higher Partial pressure of oxygen and carbon dioxide levels within the body which can be very dangerous if not monitored and kept within safe levels. Carbon dioxide controls your breathing rate and if your breathing gets out of control is what usually causes a diver to panic. Oxygen can cause a diver to go into convulsions if the partial pressure gets to high which can come about without any warning. On the surface this is not much of a problem but underwater if the diver experiences convulsions they may spit out the regulator which can obviously result in drowning. This could happen more easily to ‘out of condition divers’ where poor physical condition reduces stamina, with the increased exercise increasing the CO levels. Excessive amount of Carbon Dioxide also increases the likelihood of ‘Decompression Illness’.

Some predisposition factors for Decompression Illness
- Loss of body fluids; Dehydration is one of the main causes of DCI; this can be caused from urination, perspiration, breathing dry gases, alcohol or drug consumption.
- Poor or impaired circulation, which can arise from prior operations, accidents, old age, previously suffering from DCI and obesity.
- Carbon Dioxide build up
- Equipment not properly maintained or prepared, poor physical fitness or heavy exertion.
- Physical Labour- heavy lifting or task loading resulting in over use of joints and muscles.
- Ignorance – not knowing how to use, or adhere to dive tables.

All of this is taught in our courses, where you will learn about equipment configurations, oxygen and nitrogen levels and much more. 

The above predisposition factors for decompression illness show that you can reduce the risk in three out of the five points by maintaining a reasonable level of fitness: And your overall health will improve!

Nobody benefits from being overweight, so lets start talking about diets. Simply put, a diet is what you eat. A common misconception is that when you diet, you’re only eating things like boiled eggs and pineapple, (just an example). Following a fad diet like that will never achieve any goals.

What to eat!
Gain or Lose Weight :
Protein: Try to get two grams per kilo of body weight per day from sources such as chicken, lean meats, eggs, low fat milk or fish. Also a good whey and casein protein powder is an easy way to get your protein intake up.
Carbohydrates: Get most of your carbohydrates from wholegrain bread, potatoes, rice, pasta, vegetables or oats. A few pieces of fruit every day are also good for you.
Fats: Stay away from Saturated fats which come from animal products. Good fats are Monounsaturated (olive and canola-oil) and Polyunsaturated (fish and vegetable oils).

To Lose Weight:
There are many different ways to ‘diet’. I prefer to cut down my intake of carbohydrates for between five and seven days, getting 50% of my calories from fat and the other 50% from protein. Following this with one or two days consuming as less fat as possible resulting in an intake of approximately 40% from protein and 60 % from complex carbohydrates.
The Zone Diet: Your calorie intake should be equal parts protein, carbohydrates and fat.
Low Fat Diet: Doesn’t work for me. My energy level is a roller-coaster ride; I have to eat every two hours to stay sane. Might work for you though. There’s only one way to find out! You could try to have your first three daily meals of protein and carbohydrates followed by three consisting of protein and fat. Separating carbohydrates from fat will minimize the output of insulin, which is very important when trying to reduce fat.
One thing to remember is drink LOTS of water.

How Much To Eat.
Many small meals are better than a few large ones; Aim for around six a day.
Clean up your eating habits and learn how to count those calories. 
Buy a good food scale and keep a food log so you know what works and what doesn’t. 
After a week or so of clean eating reduce your daily calorie intake to equate to 500 a week until you lose no more than a kilo each week; losing any more than that is loss of muscle mass.

To gain weight 
Increase your protein intake to exceed 2.5 grams per kilo per day. 
Increase food with approximately 500 Calories per day for a week until you see an improvement in bodyweight. There’s no point in getting to fat so pay attention to you’re waist and not just the scales! To gain muscle you will also gain a small amount of fat.

How to train
Cardiovascular fitness is very important for the technical diver as it reduces air consumption, which not only enables diving with smaller and therefore lighter tanks, but it also reduces the risk of decompression sickness.

To increase your Cardiovascular capacity you need to raise your heartbeat for 15 minutes or longer. Participate in exercises such as jogging, cycling, swimming, step machines or skipping. It doesn’t matter what you do as long as you do it!! Aim for three to four times per week. You can do the less demanding forms of exercise for longer periods or the higher ones for shorter. Varying your training makes it more fun. Try a round with a skipping rope for one minute (full speed) followed by a rest for 30 seconds. Repeat this cycle until you’ve had enough, next time try to increase the number of ’rounds’. Try the same with running and walking; it works very well.

Strength
Also important but you don’t have to look like a body builder. A well-balanced weight training program with a bit of extra work on legs, back and waist is what you need. Doing too much is counterproductive. Quality, not quantity is what matters.

45 Minute Circuit
This workout will give a combination strength and cardiovascular workout in one 45-
minute session. The key is to move from exercise to exercise as quickly as possible.
Select a weight for each exercise that leads to failure in 12-15 repetitions.

1. 5 minutes warm up on the treadmill
2. 1 set to failure of the following exercises:
• Chest Press
• Leg Press
• Lat Pulldown
• Hamstring Curl
• Biceps Curl
• Triceps Press
• Crunches
• Leg Extension
• Shoulder Press
• Calf Raise
• Seated Row

3. 5 minutes stationary bike, moderate intensity

4. 1 set to failure of the following exercises:
• Crunches
• Lunges
• Chest Press
• Biceps Curl
• Calf Raise
• Lat Pulldown
• Triceps Press
• Seated Row
• Leg Extension

5. 5 minutes elliptical, high intensity

6. 1 set to failure of the following exercises:
• Chest Press
• Hamstring Curl
• Triceps Press
• Leg Extension
• Biceps Curl
• Calf Raise
• Shoulder Press
• Lat Pulldown
• Crunches

7. 5 minutes elliptical, high intensity

8. 5 minutes cooldown on treadmill

This exercise should take you 45 minutes to complete and should be done twice a week for 4 weeks when preparing for any technical diving activity