Posts

Diving in Extreme Weather

by Sean Harrison:
##Emergency Response Diving International, ERDI, is always traveling around the world learning from public safety divers in the field. During our visits, it is interesting to see how various teams prepare for seasonal changes within their region. These changes can range from extreme to minimal. In the North American regionsthis time of year, the preparations generally focus on extreme cold and ice, whereas the southern regions focus on heavy rains and flooding. In both regions however,preparation is needed.

Teams have a wide variety of training environments at their disposal; from pool facilities to lakes, ponds, and even oceans. To simulate ice training, teams will cover one corner of a pool with a thick piece of plastic that has a hole cut into it, just like the hole that would be cut in real ice. The rest of the pool is covered in a thin sheet of plastic to simulate an overhead and darker environment. This allows the team to practice for winter calls before the first snowflake of the season falls. All the same protocols are followed including: line pulls and communications, harnesses, tie-offs, and surface support. There are even teams that have cars completely cleaned and equipped with lexan windows submerged for training. When punched, the window will drop as if the glass has been broken. They will use manikins of all shapes and sizes to simulate whatever the team may encounter, and seatbelt webbing so divers can practice cutting and freeing victims. While this is not exactly like diving on and under the ice, it works as a great refresher and gets a team thinking of all the required steps and protocols for working in these conditions.ice hole As with colder water and environmental changes, public safety responders must take into account the physiological changes too, for example, dexterity of finger movements which would decrease in these conditions. Preparing for entanglements is a necessity as first reponders must be able to free themselves in case of an entanglement. Wearing the proper personal protective equipment (PPE) as a diver, as well as tender support. Making sure to use ice rescue suits for static water conditions, as they are not intended for moving water applications.

Teams in areas where floods are expected, train for two different types of exercises: flooded homes and cars, as well as swift water. Training for stagnant flood water varies depending on location and team structure. Generally, it consists of how the team should be properly equipped, in regard to contaminated water,search patterns, and marking protocols. For areas where swift water is an issue, teams go through exercises of knot tying, finding anchor points, ropes and high lines, load bearing calculations and when not to deploy personnel into the water.

This extreme weather training, along with routine training ensures the best possible outcome for the victims, along with helping to insure the entire team comes home safe. While these extreme weather scenarios cannot be re-created for training purposes, when the time comes, these teams will be better prepared than if they had not trained at all. The hopes are that prior to an actual call-out, the team will get a chance to practice on the ice or in swift water. Unfortunately, this is not always the case. Early season ice draws unknowing victims and flash floods come without warning, hence the name. A necessary point that needs to be stressed is: every department/agency must have a solid documented SOP and SOG. This not only protects the rescuer, but also the department.

Teams all across this nation and the world provide an excellent service to the community and ERDI hopes to be able to visit as many as we can, and highlight their efforts. If you have a story about your team working in extreme weather conditions, please send it in along with any supporting photographs.

Dive Computers vs. Dive Tables

Picture this – I’m riding to the dive site in my horse and buggy, and calculating my no decompression limits on my abacus. If you think that takes time, that’s nothing, it’s chiseling my dive plan into my stone tablet.

 

Signs and Symptoms of Decompression Sickness

A brief discussion of decompression sickness (DCS) symptoms, as well as, how to prevent and immediate treatment.

3 Questions You Should Never Ask Your Instructor

There really is never a bad question but always think about the question before you ask it; put yourself in the instructor’s fins. Questions are an important tool for instructors when teaching, they let the instructor know what the diver is thinking and chances are good that if one person has a question, others have may have the same but are hesitant to ask.

Advanced Certified or #AdvancedDiver

by Sean Harrison:

advanced dive buddies

photo credit: Santiago Estrada

As divers who catch the “bug” we are always looking for the next reason to go for a dive or to meet up with other divers and start building our list of dive buddies. Building this network is a must so when the urge hits and the conditions are right you can send that text, email or make that call, “weather is perfect for a dive…you in?”. One of the greatest forms of networking is continuing education, hanging out at your local dive shop is not too bad either, and the logical course to take after Open Water is Advanced, or is it?

The first question you need to ask yourself is, am I getting advanced certified so I can show my “advanced card” or so I can truly be a more capable diver? These are two very different things. The commonly referred to advanced certification (by most course requirements) is an introduction to five different types of diving and in most cases, two of the five introductions are core requirements such as deep and navigation. While this course provides you with an introduction, basic knowledge and additional dives, it does not truly provide you with in-depth knowledge on any of the five specialties or an opportunity to apply the knowledge you have learned.

Just like any learning experience, knowledge learned under the guidance of an instructor is only part of the equation. Taking this new knowledge and the skills associated with it, you need to get with that group of dive buddies and apply it. Furthermore, figure out what works and does not work for you, then take that feedback and give it to your instructor or dive center and have them coach you through what will make your diving experience better. All of this takes time and cannot be accomplished in five dives, in the same conditions, with the same instructor and the same dive buddies.

To build your comfort in the water you need a few things: different environments (ocean, fresh water, currents, boats, shore, to name a few); different dive buddies, some with the same diving abilities, some that are better; and most importantly… you need DIVES! Becoming a competent and efficient diver takes time and dives, and isn’t that why you wanted to learn in the first place, so you could dive?

advanced certIn short let’s go back to the original question – are you taking your advanced diver course for the card or so you can be a better diver? If your answer is so you can be a better diver, and I hope it is, consider this: take your time, take more courses, spend time in the water with your instructor, and more importantly go diving with your dive buddies and log some dives. What’s the worst that can happen? You’ll see cool stuff, meet fun like-minded people, and you’ll become a better diver!

SDI’s Advanced Diver Development course starts the minute you finish your Open Water Scuba Diver course and in fact, includes the four dives you did during your course! The philosophy is pretty simple, earning credits for your fun dives mixed with training from an SDI instructor.

Follow this link then go to your local dive center and map out the best path for you to become a better diver and a better dive buddy. Don’t forget to pick-up some marine life identification books too so you can identify all those great things you are going to see.

5 Things You Can Practice on Every Dive

Here are five tips you should do on every dive whether you dive every day or once a year. – #AlwaysLearning

Diving Without a BCD

by Sean Harrison, VP of Training

BCDAs article topics were being discussed, diving without a BCD (buoyancy control device) caught my attention and I jumped right on it. I did this for a few reasons. Over the years I have dived with many different BCDs, and in some cases without a BCD. I have also seen and heard of divers diving without a BCD (for the wrong reasons) and using the wrong BCD for the dive they had planned.

Let’s look at what not to do or use for a BCD. Often divers will get very comfortable with a BCD, and rightfully so. A good BCD should fit perfect, feel comfortable and the diver should know where every pocket and clip is, but one BCD may not be right for all types of dives.

Divers buying their first set of gear will choose equipment that is suited for the dives they have always wanted to do or for the trip they have planned, and often times this means warm tropical dives. For these types of dives, focusing on the BCD of course, the best BCD is one that provides appropriate lift for minimal thermal protect and features a single cylinder attachment. The BCD may also be very streamlined and have D-Rings made of plastic that are located in areas where lights and slates or even a camera may be attached. While this type of BCD is well suited for these dives, it will not work for colder dives, which require a lot more weight for the diver to submerge, or for technical dives, where the diver will be carrying additional cylinders. Technical BCD’s typically have metal D-Rings that are adjustable and are located differently so that stage bottles can be clipped in the correct location. Technical BCD’s also will have interchangeable air cells so the lift capacity can be increased or decreased based on what the diver is carrying. Finally, these BCDs also have the capability of attaching to a rebreather, if the rebreather is designed to be used with the diver’s BCD.

The final item on the ‘what not to do’ list is use other forms of trapped air as a buoyancy device. Divers have been known to use their drysuits as a primary buoyancy device. This is not only an unsafe practice, it also goes against most manufacturers’ recommendations (check owner’s manual for specific recommendations on how to use drysuit). In theory, this sounds like it would work, the diver is controlling one air space, the drysuit, rather than two, the drysuit and BCD, but it just does not work out that way. The unsafe aspect of using a drysuit as a ‘BCD’ is that the suit has seals to keep the air in, should a diver change his attitude to be vertical to make an ascent, the neck seal would vent excess air, decreasing the lift capacity and causing the diver to descend or swim harder to continue to ascend. This cycle would keep repeating itself, as the air expands during ascent.

Now for the slightly more sensitive subject of no BCD, this is really only practiced in commercial diving application where divers are tethered (connected by a line to a tender on the surface) to the surface and the surface support staff control their descent and ascent, sometimes by pulling on the diver or by raising and lowering a platform. These divers have no need to achieve neutral buoyancy and the additional air cell would only get in the way and may be punctured by sharp objects. Sport and technical divers should never consider diving without a BCD that has an air cell.

A BCD is just like any other ‘tool for the job’ in that you should pick the right BCD for the dive you are planning. There are simple solutions and BCDs that will work for multiple types of dives by simply changing out the air cell (adjusting lift capacity). This option allows the diver to get comfortable with one harness system and build the muscle memory of where his inflator, cutting device, lights and safety equipment are attached. The best thing to remember is to use the right BCD and don’t just use what you have, or you may find yourself in a sticky situation.

Contact SDI TDI and ERDI

If you would like more information, please contact our World Headquarters or your Regional Office.

Tel: 888.778.9073 | 207.729.4201
Email: Worldhq@tdisdi.com
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