TDI Closed Circuit Rebreather (CCR)

TDI Closed Circuit Rebreather (CCR) 2018-06-27T18:27:55+08:00

Project Description

TDI Closed Circuit Rebreather (CCR)

There are several possibilities for training on a Closed Circuit Rebreather with TDI, course options are;

  • Air Diluent CCR Diver
  • Air Diluent CCR Decompression Procedures Diver
  • Helitrox Diluent CCR Diver Decompression Procedures Course
  • Mixed Gas CCR Diver
  • Advanced Mixed Gas CCR Diver

which you choose will depend on your current certifications, experience, and your goals. All courses are unit (CCR) specific, so the first task is to choose your unit, this is no small task in itself, feel free to contact us for some impartial advice.

Get in touch, tell us what your goals are, any CCRs you have an interest in, and your current open and/or closed circuit certifications and experience, we can offer advice and the benefit of experience.

Course skill and knowledge requirements are set by both TDI and the CCR manufacturer, there will be some differences from one unit to another, and course content may vary depending on the level you are currently trained and experienced to.

Typical academic topics will include

1. History and Evolution of Rebreathers
2. Comparison of Open Circuit, Closed Circuit and Semi Closed Circuit Rebreather Systems and the Benefits/Problems with Each
3. Practical Mechanics of the System
a. Assembly and disassembly of the unit
b. Layout and design of the unit
c. Absorbent canister design and maintenance
d. Proper packing of canister, in accordance with manufactures recommendations
e. Breathing loop de-contamination procedures
f. Manufacturer supported additional items (automatic diluent valve, etc.)
4. Gas Physiology
a. Oxygen toxicity
b. Nitrogen absorption
c. CO2 toxicity
d. Gas consumption
5. Electronic and Manual Systems Design and Maintenance
a. O2 metabolizing calculations
b. Fuel cells
i. Maintenance
ii. Replacement
iii. Manufacturing date
c. System electronics functionality and calibration procedures
6. Dive Tables
a. Constant partial pressure of oxygen (PPO2) theory
b. Central nervous system (CNS) and awareness of oxygen tracking units (OTU)
7. Dive Computers
a. Mix ajustable
b. Constant PO2
c. O2 integrated
8. Dive Planning
a. Operational planning
b. Gas requirements including bailout scenarios
c. Oxygen limitations
d. Nitrogen limitations
9. Emergency Procedures
a. Use of B.A.D.D.A.S.S.
b. Three H’s problems
c. Flooded loop
d. Cell warnings
e. Battery warnings
f. Bailout gas requirements
10. Helium Considerations
a. Helium absorption and elimination
b. Advantages of hyperoxic mixes for decompression
c. Advantages of helium for bottom gas
d. Hypoxia
f. Effects on respiration
g. Effects as an insulator
h. Helium limitations

Skills practiced in the open water will include

1. Pre dive checks
a. Unit build-up
b. Scrubber packing
c. Positive and negative checks
2. Verify diluent and O2 cylinder contents using O2 analyzer where appropriate
3. Demonstrate correct pre dive planning procedures including
a. Limits based on system performance
b. Limits based on oxygen exposures at chosen PPO2 levels
c. Limits based on nitrogen absorption at planned depth and PO2 set-point
d. Thermal constraints
4. Emergency procedures
a. Mouthpiece familiarity drills
b. Gas shutdowns and loss of gas
c. Broken hoses
d. Flooded absorbent canister
e. CO2 breakthrough
f. Semi-closed mode
g. Low oxygen drills
h. High oxygen drills
i. Flooding Loop
j. Electronics and battery failure
k. Properly execute the ascent procedures for an incapacitated CCR diver
5. Use of BCD/suit and effective management of loop breathing volume for buoyancy control
6. Stop at 3-6 metres / 10 – 20 feet on descent for leak bubble check
7. Electronics systems monitoring for PO2 levels (SETPOINT) and switching set-points
8. Manual control of set-point if electronically controlled CCR is not used
9. Use of lift-bag / delayed surface marker buoy and reel
10. Proper execution of the dive within all pre-determined dive limits
a. Constant-loop volume management
11. Post dive clean of unit to avoid contamination and spread of disease
12. Dive maintenance of unit
a. Cell remove and replace
b. Mouth piece strip and rebuild
c. Replacing batteries

Decompression related in water skills

1. Demonstrate comfort swimming on surface and at depth carrying 1 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 or lift-bag 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 1 minute
7. Oxygen rebreather mode at less than 6 metres / 20 foot stop
8. Complete 1 bailout scenario at depth to include decompression obligation on open circuit

Student prerequisites vary depending on which course you choose, and the CCR you will train on.

The Air Diluent Closed Circuit Rebreather Diver course requirements are

1. Minimum age 18
2. Provide proof of 20 logged open water dives
3. Provide proof as a TDI Nitrox Diver or equivalent from agencies recognized by TDI*
4. If the rebreather is a TDI approved sidemount rebreather, the student must hold the TDI Sidemount Diver certification or equivalent, provide proof of 10 logged sidemount dives, and any additional requirements the sidemount rebreather manufacturer may have.

The Air Diluent Closed Circuit Rebreather Decompression Procedures Diver requirements are

1. Minimum age 18
2. Provide proof of 50 logged dives
3. Provide proof of TDI Advanced Nitrox Diver and Deco Procedures Diver or equivalent from agencies recognized by TDI
4. If the rebreather is a TDI approved sidemount rebreather, the student must hold the TDI Sidemount Diver certification or equivalent, provide proof of 10 logged sidemount dives, and any additional requirements the sidemount rebreather manufacturer may have.

The Helitrox Diluent Closed Circuit Rebreather Diver Decompression Procedures Course requirements are

1. Minimum age 18
2. Provide proof of 50 logged dives
3. Minimum certification level of TDI Advanced Nitrox Diver, Deco Procedures Diver or Helitrox diver or equivalent from agencies recognized by TDI
4. If the rebreather is a TDI approved sidemount rebreather, the student must hold the TDI Sidemount Diver certification or equivalent, provide proof of 10 logged sidemount dives, and any additional requirements the sidemount rebreather manufacturer may have.


5. Minimum age 18
6. TDI Air Diluent CCR Diver certified or equivalent
7. 30 hours on the CCR unit
8. Six months CCR diving experience

The Mixed Gas Closed Circuit Rebreather Diver Course requirements are

1. Minimum age 18
2. Provide a verified log of a minimum of 50 rebreather hours distributed over a minimum of 50 dives on the specific rebreather. Valid logged dives must be deeper than 9 metres / 20 feet, half of which must be deeper than 20 metres / 66 feet. 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 Decompression Procedures Rebreather/TDI CCR Helitrox Diluent Decompression Procedures Diver course or equivalent from agencies recognized by TDI

The Advanced Mixed Gas Closed Circuit Rebreather Diver requirements are

1. Minimum age of 18
2. Certified TDI CCR Mixed Gas Diluent diver, or equivalent from agencies recognized by TDI TDI Instructor Manual Diver Standards
3. Have a verified log of a minimum of 100 hours as a certified CCR diver over a minimum of 100 dives; a minimum of 50 hours and 50 dives must be on the unit specific CCR. Fifty percent of these dives must be deeper than 30 metres / 100 feet All dives to be deeper than 9 metres / 20 feet

Materials required will vary depending on the course and CCR chosen, they typically comprise of;

1. TDI Diving Rebreathers Student Manual or TDI Generic CCR On-line Course
2. Manufacturer’s manual and updates
3. Manufacturer’s Build Checklist
4. TDI CCR Preflight Checklist
5. TDI Decompression Procedures Student Manual
6. TDI Extended Range and Trimix Diver Student Manual
7. TDI Advanced Nitrox Student Manual or TDI Advanced Nitrox On-line Course
8. Rebreather Course Evaluation Form
9. Mel Clark- Rebreathers Simplified
10. Manufacturer’s minimum training standards

Recommended Additional Reading and Support Material

1. Richard Pyle – A Learners Guide to Closed Circuit Rebreather Operations
2. Kenneth Donald – Oxygen & The Diver
3. John Lamb – Oxygen Measurement for Divers
4. Barsky, Thurlow & Ward – The Simple Guide to Rebreather Diving
5. Bob Cole – Rebreather Diving
6. Jeffrey Bozanic – Mastering Rebreathers

Advance study is essential, the more time you can put into this, the more you can benefit from your time with the instructor.

Course costs will depend on the CCR, the location of the course, and the course chosen. Contact us for a personal quotation.

We have a limited number of twin bed fan dormitory rooms for 2500 PHP per person, per week. These come with a kitchenette and bathroom, simple backpacker style.

If you prefer something else we work with a number of local resorts and hotels, or you might like to check services like,  AirBNB we can help with local information if needed.

A typical hotel room starts from 1500 per night and up, the average would be around 2000 PHP. A typical self service monthly rental room or studio from 10,000 PHP and up, the average around 15000 PHP per month.

See here for more information on accommodation.

Contact the Course Director as early as possible, we can only accept a limited number of students on to each program, it is wise to book your preferred date in advance.

Please provide the following information when you book.

Are you certified as a CCR Diver?
If yes to the above, on which unit, and how many hours logged?
How many total dives have you done?
How long have you been diving?
Any significant gaps in your diving experience?
Do you hold any technical certifications, if so which ones?



Lee Butler
Lee ButlerCourse Director, EFR IT & Tec IT
Lee has been a PADI Course Director and Instructor Trainer since 2012, conducting PADI IDC’s and Instructor programs with Savedra since.
Lee is a keen open and closed circuit technical and cave diver, and brings a wealth of diving knowledge and experience to each program.
In addition to being a Course Director he is also the General Manager of Savedra Dive Center, this puts him in a great position to help you get started with your new diving career.

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Contact Info

Savedra Dive Center, Moalboal, Cebu 6032

Phone: +63 32 474 3132

Mobile: +63 917 323 0369

Web: Go Pro Philippines

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