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How to simulate blacked out water training



By: Thomas Powell

In the modern dive community, every type of diving has inherent risks. The reality is that every little niche within scuba diving will always have supporters who will claim that their type of diving is the “coolest, toughest, most interesting, or most exotic.” No matter what type of dive you perform, we all undergo training and gather experience in order to improve our knowledge, muscle memory, and general safety. The public safety diving community is one of these niche groups within scuba diving.

The primary difference between public safety divers and others is that public safety divers rarely enter the water for enjoyment. Instead, they prepare for the worst so they can serve their communities in times of need. The majority of their dives are performed in less than ideal conditions in places where bad guys realize evidence would be difficult to find. This type of diving can affect any diver’s mental state which makes training essential. Worry, fear, bravado, and desperation must all be overcome to remain safe while trying to provide service and care to others.

Evidentiary items are often tossed away into filthy bodies of water in the hope that law enforcement will never be able to perform an effective recovery

These waters may have low levels of visibility, contaminates, obstructions, and various other problematic factors. In turbid black water, visibility may get so low that adding light is like turning on high beam headlights in the fog. Only muck and particulates are illuminated. A diver’s ability to see does not improve. So how do you train for a situation in which you cannot see? Over the years, many methods have been developed.

First it must be recognized that many dive teams begin training and are developed during a period when equipment is being purchased or gathered. This factor means that newer divers are used to half-masks and have not yet moved on to full-face systems. To begin preparing for black water environments, these standard half-masks must be covered. This action can be accomplished by purchasing manufactured mask covers, or simply by covering the outer mask lens/es with something such as duct tape. If the mask can be applied to the face and no light enters, the mask is ready for training use.

Similar to half-masks, full-face masks must be prepared for black water training once a team is prepared and trained in the proper use of full-face systems. Like half-masks, certain manufacturers make covers for full-face masks. Despite this, items such as mask covers may be viewed as costly with already-tight team budgets. For this reason, many teams have learned to tape lenses in a similar fashion to half-masks, or to stuff the airspace inside masks with dark substances such as black plastic.

Methods used must not deteriorate the comfort of the divers

No matter how a team decides to eliminate visibility in masks used for training, the methods used must not deteriorate the comfort of the divers other than to eliminate visibility. Anything protruding into the face, interfering with a seal, or disrupting the actions of a dive could cause an unneeded and avoidable safety concern. Once methods are determined and safety is evaluated, the first step is to begin the training process in a confined water environment. Teams must take the time to perform search patterns, practice line pulls, simulate procedures, and perform emergency simulations in an environment where support can be offered, actions can be reviewed, and safety can be verified. A location such as a pool will allow team members to perform patterns and actions where safety divers can be readily available, and the surface can be easily reached. Skills should be performed in this type of environment until team members can perform standard operational tasks, search patterns, tactile searches, find tools and cutting devices, switch to backup gas systems, and recover from problematic situations.

Similarly, tenders and shore personnel should take the time to monitor how actions are performed and recognize how they can support and assist other team members based on specific needs while activities are visible. Remember that in black water, the diver depends on his or her tender for support, survival, and direction. Tenders and other surface personnel must be trained and practiced in providing oversight and direction to a diver on the end of a tether. Line pulls, communication-based commands, responses to stress, and reactionary commands must be practiced until they are fluid and performed with immediate recognition.

When a diver first loses the ability to see, he or she often retracts into his or her mental world

Fear can take control and it is often up to the tender to provide the calming voice and mental support. Recognizing stressed breathing or erratic behavior is an important part of the training process. Once a diver and tender can operate in support of one-another, a strong bond will have been developed that can transfer to an open water operation. This bond will help a diver learn to focus his or her mental activity on operational goals. The diver can begin to work on maintaining a tight search pattern, feeling for the item he or she visualizes in his or her mind. Essentially, team work can help a dive team focus on the missions it performs.

Once team members are comfortable in a confined water environment, practice must be moved into a realistic setting. The first objective should be to perform similar actions and tasks in a known open water location. This step will allow divers to begin to adapt to a realistic operational environment. The same basic skills performed in the pool can now be performed in open water. As comfort is established, the team can develop full operational scenarios to see how all members function when divers do not have the ability to see while performing searches. In an open water environment, the tender may no longer be able to see the diver other than bubbles and where the tether enters the water. In contrast, the diver now relies on the tender to recognize the pattern and position in an environment that is no longer a simple swimming pool. The teamwork built in confined water can help divers and tenders work together in an effective fashion. Similarly, potential problems can be recognized, evaluated, and corrected as needed.

Aside from learning to operate in black water environments, other extreme realities must be faced

Many teams get comfortable in full-face systems and as with anything, emergency skills begin to fade. This factor suggests that divers must take the time to practice bailout procedures when all visibility is lost. Again, this is a task that can first be performed in the pool, and then transferred to a controlled open water setting. Basic skill sets cannot be allowed to deteriorate while establishing comfort in tough environments. As we move forward in education, we must all remember to return to return to the basics in periodic cycles. We do not want to learn new things while forgetting what we have already learned. As a dive team member, use new education to build your educational background and work to become a better diver. The objective is to be safe and go home after every dive, not to simply build a larger stack of credentials. To be able to help your community as a public safety diver, you must stick around and grow experience, not be lost to ego and a lack of basic skills practice.

Thomas Powell is the Owner/Instructor Trainer at Air Hogs Scuba, Clayton, NC – Cave Excursions, Live Oak, FL, USA

To find out more about International Training, visit

From its humble beginning in 1994 to today, the group of training agencies Scuba Diving International (SDI), Technical Diving International (TDI), and Emergency Response Diving International (ERDI) form one of the largest diving certification agencies in the World – International Training. With 24 Regional Offices servicing more than 100 countries, the company today far exceeds the original vision the founders had when they conceived the idea on a napkin, sitting at a kitchen table in the early 1990’s.

Dive Training Blogs

Deptherapy returns to its Roots – Part 4



Join Richard Cullen from Deptherapy for part 4 of his Blog about the charity’s recent expedition to Roots Red Sea, El Quseir, Egypt.

We are all back to the house reef today; the weather is lovely, the sea calm, the tide will soon be slack, so a great day’s diving in store.

A few yards away from the beach dive centre, on the Roots’ beach is their day time restaurant. It is where we take lunch when diving, and there is a continual supply of tea, coffee and soft drinks, and some marvellous lunches.  There are also male and female toilets and a fully accessible toilet for those using wheelchairs.

A few thoughts around working with amputees and those who have paraplegia. Firstly amputees – the part of the limb remaining is known as the ‘stump’, and we have worked with a substantial number of bilateral leg amputees (both legs), single leg amputees and single arm amputees.  The level of amputation can be above or below the knee or elbow, or through the knee. In one case the amputation was transpelvic and in another through the shoulder.  Some like Chris Middleton have one leg amputated above the knee and one below the knee.  This is rare, but each type of amputation offers a different challenge.

Many people think the amputation is clean and the skin neatly tidied up after surgery. Although that occurs in a few cases, in most the stump is rather rugged.  Elasticity of the skin around the stump is often exceptionally poor and can easily be damaged.  Some of our beneficiaries, as they were injured as young men, suffered from heterotopic ossification – this is where the bone tries to grow after amputation and often penetrates the skin, resulting in further surgery being required to cut back the bone and of course the stump needs to be restitched.  Very often stumps are sealed with skin from elsewhere on the body.

Swars kitting up

Few divers have never experienced a graze or cut underwater but such an experience for those with amputations can have serious consequences.  Stumps are more likely to get cut or grazed as the skin is so tight. We all know that there are lots of infections in seawater and if infected the cut or graze can cause very serious problems for the amputee.  Tailored wetsuits are one preventative measure, as are daily stump checks, making sure there is no damage and if there is, applying medication and or protecting the stump.

Those with paraplegia provide an additional challenge, not being able to feel their lower limbs they can easily damage them, so cuts, abrasions, and even sunburn can go unnoticed.  Donning a full-length wetsuit can be a challenge as toes can easily be broken and hairs pulled out of legs.  On the Deptherapy Education Professionals’ Course we show how to fit a wetsuit properly.

In recent discussions between our dive medicine advisor Mark Downs and our VP Richard Castle, who is a consultant psychologist, we have been looking at areas for further medical research in terms of diving for those with disabilities.  One area of suggested study is thermoregulation. The theory is that those with amputations and those with paraplegia suffer more with the cold as their body is unable to regulate heat. Certainly, in Corey’s case, he feels the cold more quickly than those diving with him. Chris Middleton can feel the cold more quickly than others with amputations but that may well be that Chris is muscle and bone where, to put it nicely, others have a more substantial covering.

Some AMEDs and Dive Referees will not sign off amputees as being fit to dive. That is their professional opinion and although we can show that even triple amputees are more than capable divers, capable of progressing to Rescue Diver standard even, they still refuse to sign them off. Last year Oli and Mark invited us to speak at the UK Annual Hyperbaric Medicine Conference in London where Josh Boggi, the world’s first triple amputee Rescue Diver and a Deptherapy beneficiary spoke about how amputees can become safe and successful divers.

Corey, Swars and Michael

For Corey, he wears full leg coverings and diving boots in the water; as he cannot use his legs there is no purpose in wearing fins.

Another point around amputations is that most of the general population make an assumption that a leg amputation is the result of a traumatic incident.  That is incorrect; by far the majority of leg amputations in the UK are the result of diabetes. Those whose legs are amputated as a result as diabetes are more likely to have poor healing of the stumps.  This also presents an issue of comorbidity that may well result in an AMED or Dive Referee declining to sign them off as ‘fit to dive’.  If signed off you would need to be very aware of the health of a stump; I certainly would not take someone with an open wound diving and the fact that they will be on medication for the diabetes.  You also have to be aware that they may well be on other medication to manage pain etc.

You need to be very clear with those who have paraplegia and other conditions that they must let you know if they start to feel cold.

Managing air – diving just using your arms for propulsion can, for many, be very tiring and a considerable amount of effort is required.  This, plus other factors, may result in enhanced air consumption by the diver.  This may increase if a current is encountered, even one which most divers who have use of their legs and dive with fins would not cause the least concern.

Within Deptherapy we very much work on the ‘rule of thirds’ – a third of your air to get you down and to see what you want to see, a third to get you back to the surface and a third in reserve.  This in most circumstances will ensure no ‘low on air’ or ‘out of air’ situations.

Say if we have 210 bar in a cylinder that means 70 bar out, so turn on 140 bar, 70 bar to return and to the surface so we should have 70 bar reserve at the surface.

We also work our students through SAC rates and looking at the air consumption of others in their team.

Checking the team’s air frequently during a dive is stressed to all our Pro team.

Keiron became very engaged with this concept as the result of the online RAID study for his Master Rescue Diver.

On expeditions we normally dive in small teams, a DM/TDM with three programme members.  They work as a team and understand each other’s air consumption. Of course, they also dive as buddy pairs.

Today offered perfect conditions for diving, and Keiron, Moudi, and this time TDM Oatsie were kitted up and in the water within minutes.

Pause for thought… those with paraplegia will have different toileting arrangements to those who do not have the condition. This also applies to some who have suffered traumatic limb loss.  They may use catheters for urination, some may have Stoma bags etc.  This all has to be planned into your dive schedule to ensure the safety and comfort of your student.  For young people talking about these very personal arrangements may be very difficult.  Those with Stoma bags may be embarrassed by people seeing them.  This is another part of seeing beyond the injury or condition – it is the person inside that you are dealing with.

Corey on the Roots House Reef

So, Corey, Michael and myself were joined by Swars.  Swars, although he joined the DM programme at the same time as the other guys, because of work commitments was unable to join us in September 2019 at Roots where we ran a DM introductory programme alongside the crossover of our Pro Team to RAID.  Swars has become a really good mate; he is a great diver, with an engaging personality.

Michael and Oatsie were a known quantity to me as they had been on the September 2019 programme and both have travelled to my home dive centre Divecrew in Crowthorne, Berkshire, to work on courses, pre-COVID.  During COVID Michael and I, plus a few of the guys from Divecrew, have dived at Wraysbury together.

Just as Roots is our base in Egypt, Divecrew is our base in the UK, and through this relationship, Martin (who owns Divecrew with his wife Sue) is one of our trustees. Together they have established a centre where pretty much 100% of the Pros are Deptherapy Education trained.

I asked Swars straight away to brief a dive for Corey. I gave him the briefing slate, a few tips and then ten minutes later he came back with a perfect briefing… and I mean perfect.  So, a great briefing under his belt; now to watch him work with Corey in open water. He looked the Pro, he knew what he should be doing, he understood his role. We assigned Michael as Corey’s buddy and said he would lead the dive. I was there to assess the TDMs and supervise very closely Corey’s skill demonstrations.

Again, it comes as no surprise that many beneficiaries in Deptherapy can move straight into dive management, as several were NCOs, as was Swars, and they are used to briefing individuals and teams.

We had decided that we would mix up the dives required to complete Corey’s OW 20 RAID dives with some general diving as trim and swimming arm action are all important. We also needed to concentrate on spatial awareness.

We agreed a signal for horizontal trim and Swars reinforced the swim stroke that Corey needed to do to get propulsion.  Every time Corey moved out of horizontal trim Swars was there reminding him about trim and reminding him of his swim stroke.

The Roots’ House Reef is amazing – at a metre you encounter a shoal of black Damselfish, at 3 metres a shoal of Unicornfish, there are Butterflyfish and all manner of other fishes in great profusion.  The coral is in great condition. It really is a place of beauty and tranquillity.

Oatsie and Swars relaxing by the Roots pool after a long day

Although we had problems getting Corey underwater again, once we got him in skill demonstration mode his anxieties disappeared.  We then took him diving. Steve Rattle, the owner of Roots joined us and was taking photos that provide a great record of the week’s diving.  Steve commented on the quality of Swars and Michael’s supervision and control underwater of Corey and gave them feedback on how impressed he was.

Meanwhile on the RAID Master Rescue Course, Oatsie who was in the same Regiment, same Platoon and Section as Keiron in Afghanistan was more than willing to be a very uncooperative victim for his brother-in-arms.  I think Keiron gave Oatsie some feedback about this!

For me this was a hard week, combining running the RAID OW 20 for Corey but also the assessment of our three TDMs.  A week underwater but no opportunity to dive for myself.  People often think Deptherapy Expeditions are holidays for the Dive Team; they are not, it is hard work and I mean hard work.

Tomorrow is Day 4 in the water Day 5 of our trip. We are on the House Reef again, and things are starting to come together. Join us back here on Monday 26th October…

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Scuba Diving Instructor Ranks Scuba Specialty Classes… the good, the bad and the rubbish!! (Watch Video)



Scuba Diving Specialty Certifications! Which ones are worth your money? And which ones are just rubbish?!

This professional Scuba Instructor has strong opinions about Scuba Specialty Courses, and he’s sharing them with you!

Wreck Diver, Deep Diver, Nitrox, Buoyancy, Boat, Ice, Dry Suit, UW Photography… the list goes on and on. With so many choices for Specialty certs to get you to Master Scuba Diver level, how do you know which dive courses are of value, and which are a waste of time?

We ask 3 simple questions of each Scuba Course and rank each course’s value for you. So before you sign up for your next PADI e-learning course, WATCH THIS VIDEO!

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