Tag Archives: TDI

Advanced Nitrox

Uwe would like to congratulate Bruno P for his successful completion of the Advanced Nitrox course. Bruno has been extremely active diving with UWE and SCDC, as well he has been working towards his Advanced Nitrox and Decompression Procedures certification.

It was late in the afternoon, and we were gearing up for what was to be an extremely successful dive on Pipers Point. Visibility has been a little short but we sure lucked out. There is some large pieces of plankton in the water, but for the most part visibility was easily 50 – 60 feet. The dive was great…we saw plenty of marine life, though not large stuff, but there was some Buffalo Sculpin and some nudi’s.

Be sure to check back, as the video of some of the marine life we saw will be posted in the next day or two. Once again well done to Bruno P. Interested in taking some dive courses? Stop by the Courses Page right here at UWE, and see what we have to offer!

Video Credit: Special thanks to Red Hat Divers for their video of the NOTOX Gas Switch

General Guide Lines Covering All Dives (Tec or Rec)

I have been reading an interesting manual from IANTD and I could not get over how much this makes sense, so I thought I would share it with my readers!

  • Analyze all gases prior to diving;
  • Ensure all gases are properly and visibly labeled prior to diving;
  • Use 1.4 PPO2 on technical level exposures as a bottom and 1.6 as a maximum decompression mix PPO2[singlepic id=221 w=320 h=240 mode=watermark float=right]
  • After a period of acitvity at the surface (kitting up), allow for a short rest period in order to get breathing and heart rate back under control prior to entering water.  Experienced divers may use visualization techniques or bodycardial breathing to achieve this.  In short, wtop whatever you are doing and breathe deeply for a period of time;
  • During the descent, stop at 20ft (6msw).  Perform a leak and general equipment check.  THis wait time of an additional minute or so further allows the body to acclimate to the new environment.  Temperature and light acclimatization may take several minutes (up to 25 minutes for major light changes), however this brief stop will allow the cardio-vascular system to return to near normal rates.
  • Make a slow descent without excess exercise.  Either free fall or use hand over hand techniques with shot lines in tidal areas.  Finning down the line will use a lot of energy and produce CO2 that in turn predisposes us to narcosis and a range of other problems.
  • Having reached the bottom take another brief period to adjust equipment and attain the correct buoyancy.  All these extra stabilizing minutes are simply an attempt to return the body to a near surface functioning state such that it operates to maximum efficiency.[singlepic id=136 w=320 h=240 mode=watermark float=right]
  • During the dive, whenever possible use “pull and glide” techniques rather then heavy finning (with suitable respect for the environment).  Use of the arms reduce breathing stress.
  • If at any point during the dive a stressful situation arises, STOP, take 3 deep breaths (focus on breathing out), Think and Act in that order.  Try and prioritize the problems.  The bottom line being if I have gas I can breathe.  There is no urgency to start an ascent if at the end of the planned time something happens which slows egress providing bailout schedules are (and should be) carried.
  • If the depth of the dive is known, carry a schedule for the dive time and the dive time plus 5 minutes.  If the depth is uncertain carry a schedule for the depth and the time and the depth plus at least 10ft (3m) and the same time.  Carry an additional schedule for the longest time and deepest depth assuming a decompression on bottom mix.
  • Always plan for the deepest part of the dive even if this portion is only a bounce, i.e. if the wreck bottoms at 229fsw (70 msw), but most of the dive is at 223fsw (68 msw), plan for 229 fsw (70 msw).  Maintain ascent rates of 33ft/minute (10 m/minute) or less, even from deep water.
  • As with a no-stop dive where it is wise not to return directly to the surface (as this is a calculated pressure ceiling), it is also wise not to return directly to the  first decompression stop.  One or two minutes spent waiting 10fsw (3msw) below the first stop are beneficial when considering tissue over pressurization and will have no noticeable affect on the remaining decompression.
  • Avoid unnecessary deplays in deep water on bottom mix, such as starting up a wall after planned bottom time and then taking time to stop and look.
  • Do not reduce stop times arbitrarily.  Do not make assumptions on stop time reduction if using a non planned gas without first computing for the effects.  In a team plan this would mean carry a schedule for the worst gas scenario of the team (most deco).
  • When reaching the first stop and if using a time device which works in whole minutes.  Wait until the minute has incremented and then start the timing at that stop.[singlepic id=138 w=320 h=240 mode=watermark float=right]
  • If the stop involves a gas switch, start the stop timing after at least 3 – 4 breaths using the gas.
  • Maintain stop accurracy to +/- 1fsw (.5 msw)
  • After completing the final stop, ascend half way to the surface and stop for a further 2 – 5 minutes.
  • While waiting for the boat to pick you up, stay on the highest available FO2
  • Upon entry into the boat after a period of decompression, spend at least 5 minutes breathing your highest available FO2 on the surface.
  • Hydrate with non-acidic drinks at least 12 hours before planned extended decompression dive.  Hydrate again prior to the dive and immediately afterwards
  • Avoid alcholic beverages, caffine and decongestants prior to diving.
  • Do not smoke, especially immediately before and after a dive.

These points are pretty much common sense things, but how many people skip past some, out of complancy??

New Decompression Diver

[singlepic=135,320,240,watermark,left]Uwe would like to congratulate Mike J. and Neil P. for their successful completion of Advanced Nitrox and Decompression Procedures from TDI.  The guys started their training in early Sept, with two days of intense skills dives.  Their training was put off a couple of weeks due to some ear problems and equipment problems at the shop.

Deco Dive 1, was out on the HMCS CHAUDIERE which is an exellent training platform as it is easy to get depth fast, and also have an easy ascent line for the deco stops.  We enjoyed a nice swim through up through the operations room, into the bridge and out through the lower point on the bridge deckhead. [singlepic=137,320,240,watermark,right] Overall the dive plan was 150 for 20, and the final stop was 8 at 20 feet.  Nothing like a gas switching computer!!

Deco Dive 2 was completed today at the Tuwanek Abyss…the water temp is cooling and visibility was pretty short in the top 10 feet.  Once we broke through the top layer, the visibilty opened up to easily 100 feet, and crystal clear. We slide down the sand with the wall tight on our right….the wall had some nice chimney sponges on the wall.  We used V planner for the first time on the dive, though a bit different then the Deco Planner we normally use, it certainly has some great potential…so more investigation is needed.

Once again, congrates, and thank you to Suncoast Diving!!

New Decompression Diver

[singlepic=102,320,240,watermark,left]Uw Explorers wants to send out our congratulations to Jeremy Chesworth on completing the Advanced Nitrox and Decompression procedures course yesterday!  We planned to challenge Jeremy with a dive to 170fsw off 9 mile point.

Monday night had everyone hard at work preparing decompression mixes for the dive, while some prepared the decompression schedule for the dive.  Once completed we broke for the evening with the agreement to meet early the next day so we could get everything together and out to the dive site.[singlepic=138,320,240,watermark,right]

Once on site, we preped and rolled into the water….did our bubble checks…and then started our descent.  As we dropped through the 50 foot mark we could tell there was a bit of a current.  So our intial swim was going to be a but harder then expected but there were no problems as we finally arrived at the scar that leads to the deep drop off!  Visiblity was at least 150 feet, and water temps were still good for decompression!!

Overall it was a great dive…interested in becoming a Tec Diver…be sure to check our courses tab right here at the website!!

Dive 5 to HMCS Chaudiere

[singlepic=100,320,240,watermark,left]Jeremy was out on his first full Decompression dive on Saturday, and he did an awesome job!  The dive has been in the planning stages for a good three weeks, but getting the stars aligned, and the moon right took some times and everyones schedules had to work out…so this Saturday it was….and off we went.

With the dive plan made, gas analyzed, we were out on the water by noon, and some 25 minutes later we were tying up to the mooring buoys on the Chaudiere.  We went over the dive briefing one more time, decompression tables set up…and we started to gear up.  Once everything was in place we did our roll in, slung our decompression bottles….took a second or two to catch our breaths….it was time…ready, lets go![singlepic=105,320,240,watermark,right]

We descended down the line and once at the 60 foot mark we staged our first deco bottle….and the second bottle was dropped at the 75 foot mark.  Everything was set, so off the boat we went and dropped down under the ship in to the 146 – 150 foot mark, much to my surprise there was a lot of vegetation there with tons of prawns jumping around.  We puttered around at depth, got comfortable….and set up for our first penetration.

At minute 8 we slide up to the first cut out on the port side and slowly made our way up into what can only be 1 mess.  To our right is the doorway that takes you on to Burma Road or 3 deck, with a quick descent [singlepic=109,320,240,watermark,left]into the Forwards crew heads….and back down and out the cut out back into 130 feet of water.  Another 20 minutes or so of exploration followed with two more penetrations for the fun of it.

We found ourself about 2 minutes behind on the Deco schedule, though thankfully our computers cleared with plenty of time and gas remaining.  All went well!!

Jeremy has one more dive left and he is going to be a full fledged rookie Tec Diver!!

Busy Week Training

[singlepic=104,320,240,watermark,left]Another busy week has passed with many different course going on. Jeremy and Bruno were completing Dive 3 + 4 of the Advanced Nitrox and Decompression Procedures course. Congratulations to Jeremy for completing his Advanced Nitrox!!! The training dives were conducted out at Tuwanek Point and then Tuwanek Island Left.

The first dive was all skills, though challenging both students did a fantastic job. The skills completed were V drills, S Drills (No mask), Donning and Doffing of cylinders with and without mask. Lift bag deployment, and then actual decompression stops…and NOTOX switches.[singlepic=102,320,240,watermark,right]

The next training dive was more of an exploration, with another S drill and full v drills. Knowing how dry skills can be…it is so important to ensure that the drills become second nature in the event there is an equipment failure.

Jeremy’s next dive is going to be a decompression dive on the HMCS CHAUDIERE. I am so looking forward to the one.

[singlepic=103,320,240,watermark,left]Interested in doing some training….there is a Wreck Course starting on Friday, the 8th of Aug…with one more seat available…or you interested in doing some Technical Dive Training….be sure to visit Suncoast Diving for more information.