TDI Hollis Prism II CCR Course
The Prism2 is a fully closed circuit Rebreather, ideal for exploring open ocean, cave, or wrecks. This unit can be electronically or manually controlled which means you choose how you want the loop PPo2 maintained.
The TDI Closed Circuit Rebreather (CCR) Air Diluent Diver Course is your first step into closed circuit rebreather diving and your first truly quiet dive experience!
Using the latest technology in CCRs can maximize your gas supply and provide an optimum breathing gas for any depth by maintaining a constant partial pressure of oxygen. It’s like having a nitrox blending machine on your back!
During this course, your TDI Instructor will teach you all of the necessary skills to conduct no decompression CCR dives to a maximum depth of 30 metres/100 feet using air diluent.
This course is for the certified diver looking to advance their diver level training and equipment configurations by learning to dive a rebreather. Whether you are an avid photographer, want to experience the silence of diving a rebreather, or looking to get closer to the marine life – rebreather diving is for you.
Note: Intro To Tech or remedial skills development may be required if the student is unable to demonstrate excellent bouyancy control and other basic skills.
- Minimum age 18
- Provide proof of 20 logged open water dives
- Provide proof as a TDI Nitrox Diver or equivalent from agencies recognized by TDI
What you can expect to learn:
The TDI CCR Air Diluent Diver course takes an in-depth look at all of the following and more:
- History and evolution of rebreathers
- Comparison of open circuit (OC), closed circuit, and semi-closed circuit, rebreather (SCR) systems noting the pros and cons of each
- Practical mechanics of the system
- Gas physiology
- Proper scrubber packing: in accordance with manufacturers recommendation
- Electronic or manual systems design and maintenance
- Dive tables
- Dive computers
- Dive planning
- Emergency procedures
- Dive checklists
- Predive checks
Some of the required skills you will have to demonstrate include all of the following and more:
- All open water dives must be between 9 metres/30 feet and 30 metres/100 feet
- Two dives must be deeper than 20 metres/50 feet and one dive must be deeper than 27 metres/90 feet
- Partial pressure of oxygen not to exceed manufacturers recommendation or a working limit of 1.3
- All dives to be completed within CNS percentage limits with a recommend maximum of 80 percent of the total CNS limit
- Where the user opts for an automatic diluent valve (ADV) fitted and approved by the manufacturer, additional skills such as regular diluent gauge monitoring and addition control must be emphasized
- Unit build up and break down
- Predive checks
- Verify diluent and oxygen contents using an analyzer
- Demonstrate correct predive planning procedures
- Cover emergency procedures
- Use of BCD/dry suit and effective management of loop breathing volume for buoyancy control
- Stop at 13-6 metres/ 10-20 feet on descent for leak/bubble check
- Electronic system monitoring for partial pressure of oxygen levels (set point) and switching set points
- Use of lift bag, or surface marker buoy and reel, where appropriate
- Proper execution of the dive within all pre-determined limits
- Demonstration of safety stops at pre-determined depths
- Constant loop volume management
- Post dive clean of unit
- Diver maintenance of unit
What’s in it for you?
Upon successful completion of this course, graduates may engage in diving activities utilizing the CCR they were trained to dive without direct supervision of the TDI Instructor so long as the following limits are adhered to:
- The diving activities approximate those of training
- The areas of activities approximate those of training
- Environmental conditions approximate those of training
- To a maximum depth of 30 metres/100 feet
- No decompression dives are permitted
TDI CCR Air Diluent Diver minimum requirements:
- Satisfactorily complete the TDI CCR Air Diluent examination with a passing score of 80%, followed by 100% remediation by the Instructor
- Complete all open water requirements efficiently
- Demonstrate mature and sound judgment concerning dive planning and execution
- Course must be completed within 6 weeks from the starting date
- Complete a refresher course following a period of inactivity greater than 6 months following the course
The following equipment is required for each student:
- Hollis Prism II CCR (can be rented for the course)
- Bailout bottle (40 Cubit Foot minimum) and regulator set
- Personal dive gear
- Line cutting device
- Reel or finger spool with at least 100' of line
- Exposure suit adequate for the open water environment
- Access to oxygen analyzer
How Much Does it Cost?
The TDI Hollis Prism II CCR Course costs $1500 per student. We schedule students together for group classes whenever possible unless a private class is specifically requested. Military and Public Service discounts are also available.
The course tuition covers your instruction, books, and certification card. Equipment rental (if needed), tank fills, quarry fees, and charter fees are additional.
Note: Participation in the TDI Hollis Prism II CCR Class does not guarantee certification. Each student must complete the required number of dives, all the skills, and demonstrate that they are comfortable with planning and executing safe dives using Nitrox before they receive thier certification. If a student is unable to meet the course requirements additional training may be required.
Maximum depth for the course: 130 feet.