Text Box: ITC Scuba
for lovers of the underwater world

WANT TO BECOME A TEC DIVER?

· Sidemount {read more}

· Decompression Diving {read more}

· Rebreather Diver {read more}

· Mixed Gas Diver  {read more}

CLICK HERE to read more about courses available. 

Text Box: What is Tec Diving?
Tec Diving is often described as “going beyond” the limits of recreational diving. This definition begs the question “What is Recreational Diving then?”.
Recreational Diving certifications are limited to a depth of 42m (140ft) and a bottom time limit that is defined as a “no decompression limit”.
So in terms of the definition if you want to dive deeper than 42m (140ft), you need to get into Tec Diving.
So what if you don't want to dive deeper than 42m (140ft) but want to stay longer than the Recreational Limits? The current no decompression limit on a dive using air to 42m (140ft) is around 8 minutes.
That means from the time you leave the surface until the time you have to leave the bottom, can be no longer than 8 minutes. For a dive to 30m (100ft) the  limit will be about 20 minutes.
So if you want to stay longer than these limits, you need to get into Tec Diving.  
Exceeding these limits of depth and bottom time, you actually add a “barrier” between you and the surface which prevents you from ascending to the surface, even in an emergency. 
So what do you do in an emergency? Tec training is all about safety, redundancy of equipment, gas planning to make sure you have enough breathable gas.
Because of this redundancy and safety requirement, the equipment is arranged slightly different and you carry much more breathable gas (or air).
Training will focus on the gear, gas planning, the theory of decompression, skills in dealing with the extra gear safely, and avoid mistakes.
Tec Diving is about being more aware of potential hazards, avoiding those, planning for safety and teamwork with you buddies.
Text Box: Why do they carry all those tanks?
Most Tec Dives will require some decompression stops where the diver has to stop for a given time at a specific depth to allow the absorbed inert gas to “off-gas” before he ascends to a shallower depth. (See our article about Decompression Theory in a Nutshell”).
For example if you dive to 40m a good and affordable gas is plain air. (Air consists of 20.9% Oxygen and 79% Nitrogen).
But staying at 40m for 30 minutes while breathing air, will require almost 60 minutes of decompression and many tanks, which will make the dive impractical.
Switching to a different breathing gas with a higher Oxygen content as you go shallower, will reduce the Nitrogen content, which rapidly shortens the decompression time. 
For example if you carry a small tank of 50% Nitrox (50% Oxygen & 50% Nitrogen) and another small tank of 100 Oxygen the decompression time is reduced to only 20 minutes.
The result is that you carry the main dive gas in two large cylinders, usually mounted on your back, with two smaller cylinders clipped onto the front, one with the 50% and the other with the 100%.
Why Tec Divers carry all those tanks: to be able to switch to different gasses with varying Oxygen levels, thereby shortening the decompression time.
Text Box: Tec & Recreational Diving merger on the way. 
With the advancement of technology, dive computers and a better understanding of decompression theory, Tec Diving is busy merging with Recreational Diving. 
Over the past couple of years all certifying agencies have developed programs for Closed Circuit Rebreathers for recreational divers. Only a short while ago, Rebreathers were seen as dangerous and suicide machines. 
Now it has become an everyday occurrence to see Rebreather Divers.
Text Box: What is a Rebreather? 
A Closed Circuit Rebreather is the ultimate gas recycling machine we have on this planet. The concept is very simple and easy to understand.
Imagine breathing into a plastic bag - Two things go wrong: 1) Oxygen (O2) depletes with every breath we take and 2) Carbon Dioxide (CO2) increases.
A Closed Circuit Rebreather is non other than a high-tech plastic bag with some fancy electronics to supplement the Oxygen, and a scrubber that removes CO2.

Theuns van Niekerk

Mixed Gas Rebreather Instructor Trainer

 

Text Box: DIVE COURSES
Rebreather and Tec Diving Courses

ARTICLES & VIDEOS

· Talking Fish

· Trouble Underwater

· Decompression Theory in a Nutshell

· Intimate with a Sea Squirt

· The Reef Experience

· Liluan Wreck

 

EXPEDITIONS

· Gold Treasure on Kuda Maru

· The Coelacanth in Tanzania

· WWII Wrecks in Coron

· Malaysia

· Spiegel Grove - Florida

· Tubbataha - Philippines

· The Akitsushima WWII Wreck - Philippines

Cloud Callout: If you liked this, please click on the Facebook button.