OPEN CIRCUIT vs CLOSED CIRCUIT is it worth it?

There are four levels of training asvailable

MOD 1 - Basic entry level NDL to 40m

MOD 2 - Full Decompression AIR DIL to max depth of 45m

MOD 3 - Intermediate Trimix Full decompression with Normoxic DIL 16%O2 min to max depth of 60m

MOD 4 - FULL Adv Trimix Decompression Hypoxic mixes to 100m,

PREREQUISITE SKILLS

in any diver training environments you will be assessed on your current level of skills BEFORE your course starts. If your skill level is below what is expected you will not be able to carry on with advancing your training until you are at the appropriate level. This is for YOUR safety.Why would you want to try and do things where you were not ready for? So the best thing to do is PRACTICE, PRACTICE and revise, and do MORE practice!!! If you are partaking in training from abroad, or down country assesment dives can be taken during early stages of your training. Again, if you are not up to speed training will stop and you will lose all your monies you paid for the training program. So it is really in your best interests to prepare.

Please note that we are here to help give you the skills needed to partake in these diving activities in a safe and highly competent manner.

All training is done in two segments

1. Skill development - This is where we learn the actual mechanism of the skills, take our time to develop them, practice like crazy and practice some more!
2. Skill Application - This is where you are assessed on problem solving, appropriate decision making, taking the right cause of action in emergency situations, proper dive planning, gas managment and basically putting everything you have learnt into practice.

The great thing about advancing your diver training with us is that you will never be pressured into getting into situations that you cannot manage and handle. Basically we take it as fast (or as slow) as YOUR comfort levels go. It can take you as many training dives as need be to become comfortable, confident and competent in the water ( additional traninig costs will apply) but the main focus is getting you happy in this unforgiving environment. This way partaking in these activities are on YOUR terms and you are in total control of your actions.

Once you are really happy and competent in the water with the skill level you are training towards you will undergo Skill Application. This is a pass or fail portion of the course. You will be assessed on decisions you make, individually and collectively as a team. You will have opportunities to retake skill application dives that you are not successful on. Remember the point is to be ready for these assessment dives. After 3 unsuccessful dives you will need to redo the entire Skill Development training portion of the course again.

What we have done here is price the sections individually so that means that you know exactly where you stand. If you prepare appropriatly you will need only do the required Skill Application dives,

 Prerequisites:

 Ø   Adv O/W Diver or equivalent with 50 dives

Ø   Adv EANx Nitrox certification

Ø   15 Years of age or older

Ø   Up to date divers medical within the 12 months

Course Duration:

 Ø   Theory Sessions

Ø   3 hrs Pool/Confined Water Session

Ø   Min 8 hours open water dives

TDI – MOD 2 Air Diluent CCR Diver Decompression Procedures Course

Introduction

This is the second entry level certification course for divers wishing to utilize a (CCR) for air decompression diving. The objective of the course is to train divers in the benefits, hazards and proper  procedures for diving a CCR and to develop basic CCR diving skills to a maximum 45 m using an air diluent for formal decompression diving. 

Qualifications of Graduates

Upon successful completion of this course, graduates may engage in  decompression diving activities utilizing a CCR without direct supervision so long as:

1. The diving activities approximate those of training
2. The areas of activities approximate those of training
3. Environmental conditions approximate those of training

Upon successful completion of this course, graduates are qualified to enroll in:

1. TDI Mixed Gas CCR unit specific course
2. TDI Advanced Wreck Course

Student – Instructor Ratio

Confined Water (Swimming pool-like conditions):

1. A maximum of four (4) students per active TDI Instructor is allowed. 

Open Water:

1. A maximum of 4 students per active TDI Instructor is allowed.
2. The ratio should be reduced as required due to environmental or operational constraints.

Student Pre-Requisites

One of the most important things is being ready for advancing your training. Some people think that they would like to partake in future courses to advance their skills without first ensuring that they possess exemplery base line skills. As part of the entry requirements you will undertake a skill circuit BEFORE you start your course. If you are not successfull in the skill circuit then you will need to undertake further practice before your scheduled course. Remember that we totally promote safe diver operations and under no circumstances do we want to put you into an environment that you are not ready for. If you are coming from overseas then you will not receive a refund if your skills are not up to speed. So proper preperation is essential!

The student must:

1. Be a minimum age of eighteen (18).
2. Show proof of 50 logged open water dives.
3. Minimum certification level of Advanced Nitrox Diver and Deco procedures diver or equivalent from
   agencies recognized by TDI.
   Or;
4. Be a minimum age of eighteen (18).
5. TDI Air Diluent CCR diver certified or equivalent
6. MIN of 50 hours on the CCR unit (show logged proof)
7. MIN of 6 months CCR diving experience

 Course Structure And Duration

Confined Water Execution:

Minimum of 60 minutes confined water training to a maximum of 9 m

Open Water execution:

Min 420 minutes open water training to be completed over a min of 7 dives with a gradual increase in depth each day to a maximum of 45 m

Course Structure:

1. TDI allows instructors to structure courses according to the number of students participating and their skill level.
2. The exam may be given orally if not available in a language the student understands.

Duration:

1. Minimum of 6 hours academic development and 2 hours equipment maintenance workshop. 
2. The duration of the entire course must be spread over a minimum of 5 days.

Training Materials
Required materials:

1. TDI CCR student  manual Inspiration/Evolution,  
2. Manufactures manual and updates
3. TDI Decompression Procedures Student manual
4. TDI Advanced Nitrox Student manual
5. Rebreather Course Evaluation Form

 Required Equipment
The following equipment is required:

1. A complete closed circuit rebreather.
2. Minimum of one (1) CCR dive computer and / or bottom timer and depth gauge.
3. Mask, fins and a suitable line-cutting device.
4. Slate & pencil.
5. Reel with a minimum of 50 m of line.
6. Lift Bag / Delayed Surface Marker Buoy (DSMB) with a minimum of 12 kg lift.
7. Exposure suit appropriate for the open water environment where training will be conducted.
8. Access to an oxygen analyzer.
9. Appropriate weight.
10. Bailout gas supply cylinder with a minimum capacity of 5 ltrs / 40ft3. Air or Nitrox may be used.
    In addition the Instructor and any certified “assistant” will also carry a bailout gas supply during
    all open water sessions. This redundant gas source must be greater than the Instructor and any
    certified “assistants” bailout requirements.

If travelling from overseas, we can certainly support breather tanks, stage tank set ups, sorb, etc.

Required Skill Performance and Graduation Requirements

The following open water skills must be completed by the student during open-water dives with the
following course limits:

1. All open water dives must be between 9m to 40 m.
2. Two dives must be deeper than twenty (20) m / sixty (66) ft and one dive must be deeper than
   thirty (30) m.
3. PO2 not to exceed manufacturer recommendation or a working limit of 1.3 bar.
4. All dives to be completed within CNS% limits with a recommend maximum of 80% of the total
   PO2 CNS limit.
5. Safety stops to be conducted with a minimum 3 minutes at 6 m .
6. Where the user opts for an Automatic Diluent Valve (ADV) fitted by the manufacturer additional
   skills such as regular diluent gauge monitoring and addition control must be emphasized.
7. Calculate all off board gas at 30 litres (1.41ft3) per minute usage to cover stress situations.
8. All dives to be completed within appropriate constant PO2 decompression tables.
9. Student is only certified for decompression diving on the specific CCR unit.
10. Students must do one bailout from depth on o/c to include simulated decompression.

Open Water Skills:

1. Pre dive checks.
2. Emergency procedures.
3. Use of BC/suit and effective management of loop breathing volume for buoyancy control.
4. Stop at 3-6m on descent for leak bubble check.
5. Electronics systems monitoring for PO2 levels (SETPOINT) and switching setpoints.
6. Manual control of setpoint if electronically controlled CCR is not used.
7. Use of Lift Bag / Delayed Surface Marker Buoy and Reel.
8. Proper execution of the dive within all pre-determined dive limits.
9. Constant Loop Volume Management.
10. Post dive clean of unit to avoid contamination and spread of disease.
    

Decompression related in water skills.

1. Demonstrate comfort swimming on surface and at depth carrying one bailout/decompression cylinder.
2. Demonstrate ability to drop and retrieve one bailout/decompression cylinder while maintaining position in the water column.
3. Demonstrate ability to deploy smb/liftbag solo and as a member of a team.
4. Demonstrate appropriate reaction to gas hemorrhage from manifold or first stage, SPG and primary regulator.
5. Demonstrate appropriate reaction to simulated free-flowing deco regulator.
6. Buddy breathing deco gas for at least one minute.
7. Oxygen rebreather  mode at less than 6 m  stops.
8. Complete one bailout scenario at depth to include decompression obligation on open circuit. 

In order to complete the course and achieve the TDI Air Diluent CCR rating the student must:

1. Satisfactorily complete the written examination with a pass mark of greater than eighty (80) %.
2. Complete to the Instructors satisfaction all confined and open water skill development sessions.
3. Demonstrate mature, sound judgment concerning dive planning and execution.
4. Course must be completed within six (6) weeks from the starting date.
5. Complete a refresher course following a period of inactivity greater than 6 months following the course.

TDI – MOD 3 NORMOXIC Mixed Gas CCR Unit
Specific- Inspiration / Evolution,

Introduction
This is the intermediate level certification course for divers wishing to utilize a CCR for mixed gas diving. The objective of the course is to train divers in the benefits, hazards and proper procedures for mixed gas diving on the unit specific CCR, utilizing a mixed gas diluent containing  16% percent or greater oxygen, and to develop intermediate CCR diving skills appropriate to technical diving to a maximum of 60 msw.

Qualifications of Graduates
Upon successful completion of this course, graduates may engage in technical diving activities utilizing the unit specific CCR to a maximum of  60 msw, utilizing a mixed gas diluent containing 16% percent or greater oxygen.

 Student – Instructor Ratio

Academic:

1. Unlimited, so long as adequate facility, supplies and time are provided to insure comprehensive
   and complete training. Confined Water (Swimming pool-like conditions):
2. A maximum of 2 students per active TDI Instructor is allowed or 4 with a certified assistant.

Open Water

1. 
   A maximum of two (2) students per active TDI Instructor is allowed or four (4) with a certified assistant.
2. The ratio should be reduced as required due to environmental or operational constraints

Student Pre-Requisites

The student must:

1. Be a minimum age of eighteen (18).
2. Have a verified log of a minimum of 50 rebreather hours distributed over a minimum of  50 hours on the specific rebreather. 50% deeper  20msw. All to be 9msw.  If the diver has 50 hours on another CCR unit recognized by TDI, only 25 hours are required to be on the specific unit.
3. Have completed and qualified the TDI Air Diluent Rebreather Course or equivalent from agencies recognized by TDI.

Course Structure and Duration

Open Water Execution:

1. Minimum of 360 minutes open water training to be completed over a minimum of 6 dives including 1 equipment configuration and drills practice air diluent dive to a maximum 40msw.
2. All subsequent dives to build incrementally in no greater than 10msw steps.
3. Only 1 dive is on air diluent all others are to be mixed gas dives.
4. All mixed gas dives are to be deeper than 40msw utilizing a mixed gas diluent containing 16% or greater oxygen.
5. 4 dives must be decompression dives.

Required Equipment

The following equipment is required for each student:

1. A closed circuit rebreather. This should be the students own unit.
2. Minimum of  2 bottom timers and depth gauges or 1 CCR mixed gas computer & 1 bottom timer and depth gauge.
3. Bailout gas supply in a minimum of  2 separate off-board oxygen clean cylinders. Calculated at 30 litres per minute usage to cover stress situations.
4. 2 open circuit regulators and gauges fitted to the configuration.
5. Mask, fins & a suitable line-cutting device.
6. Slate & pencil.
7. Reel with a minimum of 60msw of line.
8. Reel with a minimum of  30msw of line.
9. 2 Lift Bags / Delayed Surface Marker Buoys (DSMB’s) with a minimum of 12kg Lift.
10. Exposure suit adequate for the open water environment where training will be conducted.
11. Access to an oxygen analyzer.
12. Access to a helium analyzer
13. Adequate weight.

Required Subject Areas
The TDI Rebreather manual is required for use as a review/recap document. The Instructor may use any
additional text or materials they feel will represent the topic in an educational manner. The following topics
 must be covered during the course.

1. Gas Physiology.
2. Formula Work.
3. Dive Tables.
4. Dive Computers.
5. Dive Planning.
6. Equipment Maintenance
7. Loop configurations.
8. Additional fitted equipment and modifications
9. Integrating Oxygen Monitors for Dive Computers.
   

Special note; If the TDI Trimix course is taught in conjunction all subject matter from both courses must be covered.

Required Skill Performance And Graduation Requirements

The following open water skills must be completed by the student during open-water dives with the
following course limits:

1. No dives deeper than two hundred 60msw
2. No dives shallower than 40msw other than the 1 air diluent configuration dive. 
3. Equivalent narcosis depth not to exceed 30msw.
4. Calculate all off-board gas at 30 litres per minute usage to cover stress situations.
5. PO2 not to exceed manufacturer recommendation or a working limit of 1.3 bar during the bottom phase of the dive and 1.4 bar during the decompression phase of the dive.
6. All dives to be completed within appropriate fixed PO2 decompression tables.
7. All dives to be completed within CNS% limits with a recommend maximum of eighty (80) % of the total PO2 CNS limit.
8. The student is only certified for CCR mixed gas diving on the rebreather being used. 

Open Water Skills:

1. Verify diluent and O2 cylinder contents using O2 analyzer where appropriate.
2. Demonstrate correct pre dive planning procedures including:
3. Properly execute a recovery from a system failure and conclude the dive and decompression on
   open circuit gases carried.
4. Gas shutdowns and loss of gas, correct choice and switching to off board gases.
   5. Broken hoses – disaster scenarios.
5. Flooded absorbent canister.
6. Oxygen rebreather mode shallower than 6msw.
7. Controlled use of BC/suit for buoyancy control.
8. Pre dive checks.
9. Stop at 3-6 msw on descent for leak bubble check.
10. Remove and replace side mounted stage cylinders under water.
11. Deployment of a Lift Bag / Delayed Surface Marker Buoy (DSMB) at depth and mid water.
12. Electronics systems monitoring for PPO2 levels.
13. Proper execution of the dive within all pre-determined dive limits.
14. Demonstration of decompression stops at pre-determined depths.
15. Post dive clean of unit to avoid contamination and spread of disease.

In order to complete the course and achieve the TDI Mixed Gas CCR rating the student must:

1. Complete to the Instructors satisfaction all confined and open water skill development sessions.
2. Demonstrate mature, sound judgment concerning dive planning and execution.
3. Satisfactorily complete a written examination with a pass mark of greater than eighty (80) %.
4. Course must be completed within six (6) weeks from the starting date.
5. Complete a refresher course following a period of inactivity greater than 6 months following the course.

PREREQUISITE SKILLS

in any diver training environments you will be assessed on your current level of skills BEFORE your course starts. If your skill level is below what is expected you will not be able to carry on with advancing your training until you are at the appropriate level. This is for YOUR safety.Why would you want to try and do things where you were not ready for? So the best thing to do is PRACTICE, PRACTICE and revise, and do MORE practice!!! If you are partaking in training from abroad, or down country assesment dives can be taken during early stages of your training. Again, if you are not up to speed training will stop and you will lose all your monies you paid for the training program. So it is really in your best interests to prepare.

Please note that we are here to help give you the skills needed to partake in these diving activities in a safe and highly competent manner.

All training is done in two segments

1. Skill development - This is where we learn the actual mechanism of the skills, take our time to develop them, practice like crazy and practice some more!
2. Skill Application - This is where you are assessed on problem solving, appropriate decision making, taking the right cause of action in emergency situations, proper dive planning, gas managment and basically putting everything you have learnt into practice.

The great thing about advancing your diver training with us is that you will never be pressured into getting into situations that you cannot manage and handle. Basically we take it as fast (or as slow) as YOUR comfort levels go. It can take you as many training dives as need be to become comfortable, confident and competent in the water ( additional traninig costs will apply) but the main focus is getting you happy in this unforgiving environment. This way partaking in these activities are on YOUR terms and you are in total control of your actions.

Once you are really happy and competent in the water with the skill level you are training towards you will undergo Skill Application. This is a pass or fail portion of the course. You will be assessed on decisions you make, individually and collectively as a team. You will have opportunities to retake skill application dives that you are not successful on. Remember the point is to be ready for these assessment dives. After 3 unsuccessful dives you will need to redo the entire Skill Development training portion of the course again.

What we have done here is price the sections individually so that means that you know exactly where you stand. If you prepare appropriatly you will need only do the required Skill Application dives,

TDI – MOD 4 ADV MIXED GAS CCR Unit
Specific- Inspiration / Evolution,

Introduction
This is the highest level certification course for divers wishing to utilize the unit specific Closed Circuit
Rebreather (CCR) for advanced mixed gas diving. The objective of the course is to train divers in the benefits, hazards and proper procedures for advanced mixed gas diving on a CCR and to develop advanced CCR diving skills appropriate to technical diving to a maximum of 100 msw.

Qualifications of Graduates

Upon successful completion of this course, graduates may engage in technical diving activities utilizing the
unit specific CCR to a maximum of 100 msw utilizing any mixed gas diluent appropriate to the dive plan.

Student – Instructor Ratio

Academic:

1. Unlimited, so long as adequate facility, supplies and time are provided to insure comprehensive
   and complete training.
   

Confined Water (Swimming pool-like conditions):

1. A maximum of 2 students per active TDI Instructor is allowed or 4 with a certified
   assistant

Open Water

1. A maximum of two (2) students per active TDI Instructor is allowed or four (4) with a certified
assistant (see above; who may teach).
2. The ratio should be reduced as required due to environmental or operational constraints

Student Pre-Requisites

The student must:

1. Be a minimum age of eighteen (18).
2. Have a verified log of a minimum of one hundred (100) CCR hours distributed over a minimum of
   100 dives on the unit specific CCR. 50 % of these dives must be deeper than 30 msw. All to be deeper than 9msw. If the diver has 100 hours on another CCR unit recognized by TDI, only 50
   hours are required to be on the Inspiration / Evolution.
3. Have completed and qualified the TDI Mixed Gas Diluent CCR Course or equivalent from
   agencies recognized by TDI.

Course Structure and Duration

Open Water Execution:

1. Minimum of four hundred twenty (420) minutes open water training to be completed over a
   minimum of 7 dives including 1 equipment configuration and drills practice air diluent dive to a maximum 40 msw.
2. All subsequent dives to build incrementally in no greater than thirty three (33) fsw / ten (10) msw
   steps.
3. Only 1 dive is on air diluent all others are to be mixed gas dives.
4. All mixed gas dives are to be deeper than 40 msw.
5. 5 of the mixed gas dives must be decompression dives.
6. If the student is qualified as a TDI Mixed Gas CCR Diver or equivalent from agencies recognized
   by TDI then a minimum of 240 minutes open water training is to be completed over a minimum of 4 mixed gas decompression dives to build incrementally in no greater than 10 msw steps two dives must be deeper than 70 msw
7. Or if the student is qualified as a TDI Advanced Trimix Diver or equivalent from agencies
   recognized by TDI then a minimum of 240 minutes open water training is to be completed over a minimum of 4 mixed gas decompression dives to build incrementally in no greater than 15 msw steps.
   

Course Structure:

1. TDI allows instructors to structure courses according to the number of students participating and
   their skill level.
2. The exam may be given orally if not available in a language the student understands.
   Duration:
3. Minimum of 6 hours for academic development and a further 2 hours for equipment configuration workshop.

Required Equipment

The following equipment is required for each student:

1. A complete unit specific CCR. This should be the students own unit.
2. Minimum of 2 bottom timers and depth gauges or 1 CCR mixed gas computer & 1 bottom timer and depth gauge.
3. Bailout gas supply in a minimum of 2 separate off-board oxygen clean cylinders. Calculated
   at 30 litres (1.06 cubic feet) per minute usage to cover stress situations.
4. 2 open circuit regulators and gauges fitted to the configuration.
5. Mask, fins & a suitable line-cutting device.
6. Slate & pencil.
7. Reel with a minimum of 100 msw of line.
8. Reel with a minimum of 50 msw of line.
9. 2 Lift Bags / Delayed Surface Marker Buoys (DSMB’s) with a minimum of twenty five
   (25) lb / twelve (12) kg Lift.
10. Exposure suit adequate for the open water environment where training will be conducted.
11. Access to an oxygen analyzer.
12. Access to a helium analyzer
13. Adequate weight.

Required Subject Areas
The TDI Rebreather manual is required for use as a review/recap document. The Instructor may use any additional text or materials they feel will represent the topic in an educational manner. The following topics must be covered during the course.

1. Gas Physiology.
2. Formula Work.
3. Dive Tables.
4. Dive Computers.
5. Dive Planning.
6. Equipment Maintenance

Required Skill Performance And Graduation Requirements

The following open water skills must be completed by the student during open-water dives with the
following course limits:

1. No dives deeper than one hundred (100) msw
2. No dives shallower than 40 msw other than the 1 air diluent configuration dive. 
3. Equivalent narcosis depth not to exceed 30 msw.
4. Calculate all off-board gas at 30 litres (1.06 cubic feet) per minute usage to cover stress situations.
5. PO2 not to exceed manufacturer recommendation or a working limit of 1.3 bar during the bottom
   phase of the dive and 1.4 bar during the decompression phase of the dive.
6. All dives to be completed within appropriate fixed PO2 decompression tables.
7. All dives to be completed within CNS% limits with a recommend maximum of eighty (80) % of
   the total PO2 CNS limit.
8. The student is only certified for CCR mixed gas diving on the rebreather being used. 
   

Open Water Skills:

1. Verify diluent and O2 cylinder contents using O2 analyzer where appropriate.
2. Demonstrate correct pre dive planning procedures including:
   
3. Properly execute a recovery from a system failure and conclude the dive and decompression on
   open circuit gases carried.
4. Gas shutdowns and loss of gas, correct choice and switching to off board gases.
5. Broken hoses – disaster scenarios.
6. Flooded absorbent canister.
7. Oxygen rebreather mode shallower than 6 msw.
8. Controlled use of BC/suit for buoyancy control.
9. Pre dive checks.
10. Stop at 3-6 msw on descent for leak bubble check.
11. Remove and replace side mounted stage cylinders under water.
12. Deployment of a Lift Bag / Delayed Surface Marker Buoy (DSMB) at depth and mid water.
13. Electronics systems monitoring for PPO2 levels.
14. Proper execution of the dive within all pre-determined dive limits.
15. Demonstration of decompression stops at pre-determined depths.
16. Post dive clean of unit to avoid contamination and spread of disease.

In order to complete the course and achieve the unit specific TDI Advanced Mixed Gas CCR rating the student must:

1. Complete to the Instructors satisfaction all confined and open water skill development sessions.
2. Demonstrate mature, sound judgment concerning dive planning and execution.
3. Satisfactorily complete a written examination with a pass mark of greater than eighty (80) %.
4. Course must be completed within six (6) weeks from the starting date.
5. Complete a refresher course following a period of inactivity greater than six (6) months following
   the course.

BACK TO TOP

CLOSED CIRCUIT VS OPEN CIRCUIT?

Which way do you go?

This is a great question and one you should really be asking yourself  when wanting to get into this sort of diving.

Below I have tried to give as unbiased approach to the pros and cons of deciding which way you should go. Having spent years diving on open circuit and the last 8 years on closed circuit I have a pretty good idea of both sides of the discussion - but at the end of the day you and only you will make the decision. Hopefully this will open your mind and answer questions you may have regarding breathers.

RATIONALIZING!

A lot of people ask themselves the wrong questions when inquiring about getting into rebreathers. The first obstacle is

"I don't do enough diving to justify the expense!" - Sound familiar???

I come across this all the time. This always reminds me of the average Kiwi who owns a boat. Average expenditure people have on boats is around $30-60K. What I want to know is on average how long does that boat spend in the garage each year? Most of the time it is tucked away for 10 or more months of the year. Does that "Justify" the expenditure?  HELL NO but we love just getting into our boat and heading out with no worries don't we!!!!

I am married with 2 kids so I don't get out as much as I want to so when I do get out it is a special event that I want to maximise my time on. On an average recreational days diving that I do ( NO decompression) I spend about 100minutes per dive on a two dive day. That's 200 minutes for a days charter. Most people will do about 45 - 50 minutes in the water each dive on open circuit. That's 50% more value I just got out of my trip! What's more I didn't need two tanks and two fills for that either!!!! So you should be asking yourself -

AM I PASSIONATE ABOUT MY DIVING?

 another one is....

"I am not into technical diving I am just a recreational diver. Rebreather's are for technical divers aren't they?"

 OPEN CIRCUIT (OC)

COST

Well at first glance open oc is far cheaper initially below is a list of what the average kit set up costs you all in NZ$$ Assuming you have your own drysuit/wetsuit, mask etc etc

BC Wing -                                              $1200-1800

2 sets of regs -                                      $900 - 1400 each

HP hose -                                              $399

Deco computer (VR3) -                       $2300

Back up bottom timer -                        $499

Set of manifolded twins                       $ 1300

Total                                                       $8000.00

There are other gear needed, hang tanks, deco regs, reels, marker buoys  etc etc, but this is the direct cost of the gear.

CLOSED CIRCUIT (CCR)

Buddy inspiration                              $16, 000.00

ADVANTAGES OPEN CIRCUIT

Firstly  it is something that you already possess the most experience in. You are well tuned to the operation and procedures in open circuit. It is predictable and easy to use. AIR in tank - air to breath NO AIR in tank - NO air to breath!! That simple. Cost wise you might have some of the gear already so you can simply add to your kit to get you to the desired configuration. You can go out and do relatively advanced dives after a long period of inactivity ( although not recommended you still have the experience to be able to get out there and go and do it) There are more open circuit people than rebreather divers. Underwater problems are more definitive and immediate and you don't have to use too much brain power to solve problems - gas leaking, isolate leaking reg/valve. Reg has problem, switch to the other, etc etc. This leaves you to be able to dive a lot sooner to deeper areas than breathers. Predive checks are more simpler and less time consuming.

 ADVANTAGES OF REBREATHERS OVER OPEN CIRCUIT

I will talk about the inspiration rebreather for the advantages. First of all probably one of the biggest ones is that you are the closest to nature than you ever thought possible! With OC diving you are loud as hell, scaring fish in all directions. On the breather you really are in the silent world, so if you are into photography or videography you will be amazed how a part of the underwater world you really become and all teh fish just go about their business for you to capture on film.

From a gas usage point of view hands down kicks ass!!! On the CCR you are using one litre (on average) of oxygen a minute regardless of depth. Your Diluent you would use about 20-30 bar out of a 3 litre tank per dive. SO that means that you have roughly 500 minutes of dive time one one tank of Oxygen. Comparability tests with OC is roughly 200 times more productive.

Nitrogen management - On a CCR you are basically breathing the optimum gas mix CONSTANTLY on a dive. For example if you are at 30meters  you would be breathing a EAN32 mix. You ascend to 20meters you are automatically breathing a EAN43 mix, 16 meters EAN50, 12 meters EAN60 so basically you are offgassing using the best mix all the time. This can only be done on OC by carrying about 8 different gasses with you!!! Here you can spend huge amounts of time at 20-30m with ridiculous NDL times!!!!

 TRIMIX applications - A lot of people are nowadays wanting to spread their wings and explore deeper sites, wrecks and need helium to be able to get them there (and back). But with Helium costing 12-15c per litre this could prove expensive if you want to pursue this sport (that's on average about $250 for a 75m dive and about $320 for 100m dive in GAS ALONE!! Remembering that a breather only uses the diluent to equalize the breathing counterlungs and after that no more gas is used. I have completed about 15 dives to 85 meters on a single 10litre tank of about 25-35 minute bottom times and the tank is STILL at about 150 bar!!!!! So if you are wanting to get into trimix then you will pay for your breather in no time if you are worried about dollars!!!

Flexibility - A standard inspiration can go out and do 100m dive by simply adding side slung tanks. If you don't do a trimix dive you simply don't take the sideslung tank!! Now if you just filled your set of twins with trimix ($250 bucks later) if the dive was called off you would be stuck with that gas in your tank. So you could not do anything else with it.

BACK TO TOP

So Why get trained with Dive T.E.C.?

Pete Mesley is New Zealands most accomplished Technical diver and the most experienced. With over 1000 hours underwater at depths deeper than 50m Pete is no stranger to the vigor's of technical diving. He has lead many deep expeditions diving challenging sites all round the world, so teaches from experience.

Whether you want to learn basic decompression procedures, advanced wreck penetration techniques, Advanced Trimix  or Closed circuit rebreather training you will receive the very best training money can buy. Remember:

If you are after experience — then COUNT on  Experience!

© Dive T.E.C.
Email: info@petemesley.com

Lermontov expedition

Doing Deco after Niagara Dive

Lermontov schematic