Rebreather Question

[Demo Dan]

Just wondering what kind of experiance one would aquire when thinking of getting into rebreathers. I am a novice diver with about 150 dives under my belt and do not think I am near ready enough to get into diving rebreathers. But I would maybe like to get into them in the future once I have a lot more knowledge and experiance in good diving procedures and practices. What sort of courses or training are good to start with inorder to better understand more advanced diving?

 

[J1M1]

Just wondering what kind of experiance one would aquire when thinking of getting into rebreathers. I am a novice diver with about 150 dives under my belt and do not think I am near ready enough to get into diving rebreathers. But I would maybe like to get into them in the future once I have a lot more knowledge and experiance in good diving procedures and practices. What sort of courses or training are good to start with inorder to better understand more advanced diving?

At least for fully closed rebreather, you will have to take advanced nitrox. It's a good course to take regardless in case you don't go the rebreather route. look through www.iantd.com and dig through the standards and procedures if your looking into getting into a breather. They have all of the prerequisites listed...JD

 

[rigdiver]

AOW, EANx, Deep Diver, then Advanced EANx. Couple hundred dives under varied conditions and environments, then you can think about a fully closed CCR. Take them seriously. You must be anal about pre-dive/post dive/maintenance. Two real big sayings: Know your ppO2 and Complacency Kills. Gain RB experience slowly.
YBOD Pilot;
Bill IANTD 1982

 

[Jason Ooi]

IANTD
Closed Circuit Rebreather Diver (CCR)

A. Purpose
1. This Program is designed to train competent divers in the safer use and technology of CCR diving.
B. Prerequisites
1. Must be an IANTD Advanced EANx Diver or Advanced Recreational Trimix Diver or equivalent.
2. Must be a minimum of 18 years of age.
C. Texts
1. IANTD text Understanding Rebreathers.
2. IANTD-approved text for the particular CCR the training is taking place on. (Operations Manual/Workbook etc)
3. IANTD Student Workbook (or Student Manual and Workbook) for the specific CCR being trained on
4. (Recommended) IANTD CCR waterproof skills sheets.
D. Program Content
1. This Program must include a confined water session, followed by 8 OW dives with a minimum of 500 minutes, on the specific
Rebreather for which the diver is being trained.
NOTE: In water training is defined as a combination of confined water and open water dives.
2. Students must complete the text with the units that they wish to be qualified on.
3. Students must pass the specific CCR test with a minimum score of 80%.
4. On a minimum of 3 dives the student must carry a stage cylinder, or other bailout gas adequate to a safe ascent on.
5. A diver using Recreational Trimix in the Diluent must have use mixtures within the limits of Advanced Rec reational Trimix.
6. Two dives must be to or deeper than 50 fsw and one dive must be to or deeper than 90 fsw (27 msw)
7. To qualify from one Closed Circuit Rebreather to another Closed Circuit Rebreather, a diver must have 12 CCR dives in order
to do a crossover of which one must have been within 45 days of the program on the new CCR and must complete a minimum
of 210 minutes of in-water training with at least 2 OW dives. CCR divers qualified as Normoxic Trimix or higher must complete
a minimum of 4 dives, of which 2 are at their previous qualification level and complete 400 minutes of in water training.
8. To qualify from a Semi-closed Circuit Rebreather to a Closed Circuit Rebreather, a diver with 20 or more SCR dives must
complete a minimum of 420 minutes of in-water training in a combination of confined water and OW environments, with at least
6 OW dives. Divers with less than 20 SCR hours must complete the entire course.
E. Equipment Requirements
1. Approved specific Rebreather suitable for the training exposure. If the student does not take possession of, or have access to a
CCR within 3 months of completion of training a refresher course will be required on the CCR that must include review of
operations of that CCR, and two dives on the CCR.
2. Instructors must have and students are recommended to have the IANTD waterproof skills sheets on all confined and OW
dives.
F. Program Limits
1. There may be no more than 4 students per Instructor, except for when a CCR qualified Dive Master is used at which time the
ratio may be increased to 6 students.
2. No dives may be conducted to depths greater than 140 fsw (42 msw) or 150 fsw (45msw) if qualified as Advanced Recreational
Trimix Diver or higher.
3. The set point of the CCR must not exceed 1.3 ATA, except for failed open solenoid drills. During the drill the set point may be
set to 1.4 ATA to simulate the failed solenoid for the duration of the drill.
4. At safety or required deco stops the set point may be increased to 1.40 ATA,
5. It is recommended that the diluent partial pressure does not exceed 1.0 ATA, and the oxygen partial pressure of the bailout gas
not exceed 1.60 ATA at the MOD of the dive. If the bailout gas is a recreational trimix mixture the oxygen must be between 28
% and 40% and the Helium content must yield an END no greater than 80 fsw (24 msw)
6. All dives must be completed within the IANTD oxygen CNS% limits.
7. The instructor may use a Rebreather or OC during training sessions. It is recommended that the instructor use the Rebreather
at all times to demonstrate skills and be able to monitor the student. .
Copyright O2003 by IAND, Inc. / IANTD All Rights Reserved 38 "The Leader in Diving Education"


1985-2003 "18 Years of Excellence"

8. All appropriate safety or required decompression stops (not to exceed 15 minutes) must be performed.
G. Water Skills Development
1. A confined water session to must be completed before conducting any OW dives.
Open Water Training must include the following skills:

1. Pre-dive checks.
2. Pre-dive breathe.
3. Switch to low set point for descent and monitor the PO2 to ensure it remains within the planned PO2 range
4. Switch to planned set point once the diver is at the planned dive depth or set point change depth
5. In water leak and buddy leak check. If conditions prohibit this after entry this then immediately upon arrival at a stable depth.
Where practical this may be accomplished between just below the surface to 20 fsw (6 msw) deep.
6. Descend and insure gas addition is made.
7. Open Circuit bailout (static and dynamic drills, including at least two OC ascents to approximately 20 fsw (6 msw).
8. Buoyancy and trim on the bottom during ascent and at safety or required stops.
9. Handset/computer/pendant/gauges, etc. operation.
10. PO2 gauge monitoring to be done no more frequently that once a minute and no less often than once every four minutes
11. Hypoxia (static and dynamic drills).
12. Hyperoxia (static and dynamic).
13. Hypercapnia (static and dynamic).
14. Flood recovery (static and dynamic).
15. Remove and replace CCR on the surface and also during a dive
16. Hypoxia due to Solenoid stuck in closed position. (Reset to a low set point and maintain a higher PO 2 set point by manual
addition)
17. Hyperoxia due to Solenoid stuck in open position. (Reset to a high PO 2 set point maintain at a value less than this by valve
manipulation)
18. Dive the unit manually.
19. Minimum Loop Volume
20. Carry additional bailout gas on a minimum of three dives.
21. SCR mode of diving.
22. SMB Deployment.
23. Out-of-air, air gas sharing from OC bailout (donor remains on CCR or SCR). Stage may be handed off
24. Complex (multi-part) scenarios such as Hypoxia or Hyperoxia drill for donor while gas sharing with an out of gas diver Ascend.
25. Safety or required Stop.
26. Post dive briefing.
27. Present the following situations. The student is to perform appropriate actions and write down the suspected problem.
Inhalation counterlung inflating rapidly Suspect solenoid failure open
Feeling unusual Switch to OC
Buoyancy has changed to very negative Flooded loop
Difficult breathing counterlung at correct volume Suspect flood or Hypercapnia
Weakness in legs Suspect Hypercapnia
Shortness of breath Suspect Hypercapnia
Feeling of well being Suspect Hyperoxia / Hypoxia
Feel like you are about to blackout Suspect Hypoxia
Muscle twitching Suspect Hyperoxia
Nausea Suspect Hyperoxia
Ears ringing Suspect Hyperoxia
Hearing or visual abnormalities Suspect Hyperoxia
Feeling dizzy Suspect Hyperoxia
Extreme quietness (absence of solenoid noise) Suspect electronics off, or solenoid defective
Solenoid fires but no oxygen injected Suspect oxygen supply empty or cylinder off (valve closed) or inline
valve closed
Diluent not being added Suspect diluent cylinder empty or cylinder off (valve closed) or inline
valve closed
2 cells read high but low cell checks with diluent PO2 Suspect two high cells are in error
2 cells read high and check with diluent PO2 Suspect cell off is wrong

 

[texdiveguy]

IANTD
Closed Circuit Rebreather Diver (CCR)

A. Purpose
1. This Program is designed to train competent divers in the safer use and technology of CCR diving.
B. Prerequisites
1. Must be an IANTD Advanced EANx Diver or Advanced Recreational Trimix Diver or equivalent.
2. Must be a minimum of 18 years of age.
C. Texts
1. IANTD text Understanding Rebreathers.
2. IANTD-approved text for the particular CCR the training is taking place on. (Operations Manual/Workbook etc)
3. IANTD Student Workbook (or Student Manual and Workbook) for the specific CCR being trained on
4. (Recommended) IANTD CCR waterproof skills sheets.
D. Program Content
1. This Program must include a confined water session, followed by 8 OW dives with a minimum of 500 minutes, on the specific
Rebreather for which the diver is being trained.
NOTE: In water training is defined as a combination of confined water and open water dives.
2. Students must complete the text with the units that they wish to be qualified on.
3. Students must pass the specific CCR test with a minimum score of 80%.
4. On a minimum of 3 dives the student must carry a stage cylinder, or other bailout gas adequate to a safe ascent on.
5. A diver using Recreational Trimix in the Diluent must have use mixtures within the limits of Advanced Rec reational Trimix.
6. Two dives must be to or deeper than 50 fsw and one dive must be to or deeper than 90 fsw (27 msw)
7. To qualify from one Closed Circuit Rebreather to another Closed Circuit Rebreather, a diver must have 12 CCR dives in order
to do a crossover of which one must have been within 45 days of the program on the new CCR and must complete a minimum
of 210 minutes of in-water training with at least 2 OW dives. CCR divers qualified as Normoxic Trimix or higher must complete
a minimum of 4 dives, of which 2 are at their previous qualification level and complete 400 minutes of in water training.
8. To qualify from a Semi-closed Circuit Rebreather to a Closed Circuit Rebreather, a diver with 20 or more SCR dives must
complete a minimum of 420 minutes of in-water training in a combination of confined water and OW environments, with at least
6 OW dives. Divers with less than 20 SCR hours must complete the entire course.
E. Equipment Requirements
1. Approved specific Rebreather suitable for the training exposure. If the student does not take possession of, or have access to a
CCR within 3 months of completion of training a refresher course will be required on the CCR that must include review of
operations of that CCR, and two dives on the CCR.
2. Instructors must have and students are recommended to have the IANTD waterproof skills sheets on all confined and OW
dives.
F. Program Limits
1. There may be no more than 4 students per Instructor, except for when a CCR qualified Dive Master is used at which time the
ratio may be increased to 6 students.
2. No dives may be conducted to depths greater than 140 fsw (42 msw) or 150 fsw (45msw) if qualified as Advanced Recreational
Trimix Diver or higher.
3. The set point of the CCR must not exceed 1.3 ATA, except for failed open solenoid drills. During the drill the set point may be
set to 1.4 ATA to simulate the failed solenoid for the duration of the drill.
4. At safety or required deco stops the set point may be increased to 1.40 ATA,
5. It is recommended that the diluent partial pressure does not exceed 1.0 ATA, and the oxygen partial pressure of the bailout gas
not exceed 1.60 ATA at the MOD of the dive. If the bailout gas is a recreational trimix mixture the oxygen must be between 28
% and 40% and the Helium content must yield an END no greater than 80 fsw (24 msw)
6. All dives must be completed within the IANTD oxygen CNS% limits.
7. The instructor may use a Rebreather or OC during training sessions. It is recommended that the instructor use the Rebreather
at all times to demonstrate skills and be able to monitor the student. .
Copyright O2003 by IAND, Inc. / IANTD All Rights Reserved 38 "The Leader in Diving Education"


1985-2003 "18 Years of Excellence"

8. All appropriate safety or required decompression stops (not to exceed 15 minutes) must be performed.
G. Water Skills Development
1. A confined water session to must be completed before conducting any OW dives.
Open Water Training must include the following skills:

1. Pre-dive checks.
2. Pre-dive breathe.
3. Switch to low set point for descent and monitor the PO2 to ensure it remains within the planned PO2 range
4. Switch to planned set point once the diver is at the planned dive depth or set point change depth
5. In water leak and buddy leak check. If conditions prohibit this after entry this then immediately upon arrival at a stable depth.
Where practical this may be accomplished between just below the surface to 20 fsw (6 msw) deep.
6. Descend and insure gas addition is made.
7. Open Circuit bailout (static and dynamic drills, including at least two OC ascents to approximately 20 fsw (6 msw).
8. Buoyancy and trim on the bottom during ascent and at safety or required stops.
9. Handset/computer/pendant/gauges, etc. operation.
10. PO2 gauge monitoring to be done no more frequently that once a minute and no less often than once every four minutes
11. Hypoxia (static and dynamic drills).
12. Hyperoxia (static and dynamic).
13. Hypercapnia (static and dynamic).
14. Flood recovery (static and dynamic).
15. Remove and replace CCR on the surface and also during a dive
16. Hypoxia due to Solenoid stuck in closed position. (Reset to a low set point and maintain a higher PO 2 set point by manual
addition)
17. Hyperoxia due to Solenoid stuck in open position. (Reset to a high PO 2 set point maintain at a value less than this by valve
manipulation)
18. Dive the unit manually.
19. Minimum Loop Volume
20. Carry additional bailout gas on a minimum of three dives.
21. SCR mode of diving.
22. SMB Deployment.
23. Out-of-air, air gas sharing from OC bailout (donor remains on CCR or SCR). Stage may be handed off
24. Complex (multi-part) scenarios such as Hypoxia or Hyperoxia drill for donor while gas sharing with an out of gas diver Ascend.
25. Safety or required Stop.
26. Post dive briefing.
27. Present the following situations. The student is to perform appropriate actions and write down the suspected problem.
Inhalation counterlung inflating rapidly Suspect solenoid failure open
Feeling unusual Switch to OC
Buoyancy has changed to very negative Flooded loop
Difficult breathing counterlung at correct volume Suspect flood or Hypercapnia
Weakness in legs Suspect Hypercapnia
Shortness of breath Suspect Hypercapnia
Feeling of well being Suspect Hyperoxia / Hypoxia
Feel like you are about to blackout Suspect Hypoxia
Muscle twitching Suspect Hyperoxia
Nausea Suspect Hyperoxia
Ears ringing Suspect Hyperoxia
Hearing or visual abnormalities Suspect Hyperoxia
Feeling dizzy Suspect Hyperoxia
Extreme quietness (absence of solenoid noise) Suspect electronics off, or solenoid defective
Solenoid fires but no oxygen injected Suspect oxygen supply empty or cylinder off (valve closed) or inline
valve closed
Diluent not being added Suspect diluent cylinder empty or cylinder off (valve closed) or inline
valve closed
2 cells read high but low cell checks with diluent PO2 Suspect two high cells are in error
2 cells read high and check with diluent PO2 Suspect cell off is wrong

Looks like a 'busy' weekend course.

 

[Jason Ooi]

CC Rebrether takes them seriously.
You must monitor your Lo.07 Hi 1.3 ppO2 setting and bailout plan.
I'm just a Normoxic rebreather diver need time and log dives if go to next level..

 

[texdiveguy]

I have never even strapped one on---would at some point enjoy a 'Discovery' type class though.

 

[tamorgen]

The number of dives you have isn't that bad, but it depends on what kind of diving you've been doing, and your personal comfort level. If you've been doing caribeean reef dives in recreational gear, then you may not be ready. If you have been doing dives in low visibility, deep dives, wreck dives in more technical gear, 150 dives may be plenty. It also depends a lot on your comfort level with the mechanics of your gear. I suspect you've been diving in the St Lawerence river, since you are in Ontario, which does present it's own challenges.

If I were you, I'd enroll in a tech course. TDI's advanced nitrox, decompression procedures, and extended range courses are probably the best, but IANTD and DSAT also offer equivalent courses. You'll have to find what your local shops offer.

After that, you'll want to get into semi closed circuit rebreathers, such as the Dräger Dolphin. Each rebreather is specific and you have to take a course to be certified in each one of them. I'd recommend at least 100 dives on a semi CCR before you go onto a truly CCR.

Good luck.

Just wondering what kind of experiance one would aquire when thinking of getting into rebreathers. I am a novice diver with about 150 dives under my belt and do not think I am near ready enough to get into diving rebreathers. But I would maybe like to get into them in the future once I have a lot more knowledge and experiance in good diving procedures and practices. What sort of courses or training are good to start with inorder to better understand more advanced diving?

 

[padiscubapro]

The number of dives you have isn't that bad, but it depends on what kind of diving you've been doing, and your personal comfort level. If you've been doing caribeean reef dives in recreational gear, then you may not be ready. If you have been doing dives in low visibility, deep dives, wreck dives in more technical gear, 150 dives may be plenty. It also depends a lot on your comfort level with the mechanics of your gear. I suspect you've been diving in the St Lawerence river, since you are in Ontario, which does present it's own challenges.

If I were you, I'd enroll in a tech course. TDI's advanced nitrox, decompression procedures, and extended range courses are probably the best, but IANTD and DSAT also offer equivalent courses. You'll have to find what your local shops offer.

After that, you'll want to get into semi closed circuit rebreathers, such as the Dräger Dolphin. Each rebreather is specific and you have to take a course to be certified in each one of them. I'd recommend at least 100 dives on a semi CCR before you go onto a truly CCR.

Good luck.

As an instructor and instructor trainer on multiple units (I have also authored text books for the KISS and the MEG), If you plan on going CCR dont waste your time with an SCR.. there is little to be gained taking this small step (and in some casesmake it harder train)..

I'll take a guy with 50 dives who is confortable in the water over an old salt with 1000 dives anyday..

The old salt generally has too many bad habits to break and it makes the training much more difficult than it could be..

If you feel confrotable in the water and can pay attention to you instruments.. You are ready to take a class with a good instructor.. If the instructor doesnt have the experience, thats a different story..

If you can take a class like ANDI's CSU or the other agencies advancd nitrox before you sign up for your CCR class things will be easier, but most instructors and agencies allow you to take both at the same time...

 

[ScubaJim09]

OC experience is not nearly as beneficial as some may think when going to rebreathers. Buoyancy is entirely different, pre-dive and post-dive are different. Your mentality throughout the dive is changed. For example, the most gas is wasted on ascent because of venting the loop from expansion. On a rebreather dive, you want to get to a depth and either stay there or continue to go deeper. If you "see-saw" you will burn a lot more gas. This isn't as big of a deal with OC diving. If you are comfortable in the water and understand how oxygen and nitrogen work at increasing depth, you can figure out rebreathers.