GUE Rebreather

Course Outcomes

GUE’s Rebreather Diver course is designed to educate individuals in basic rebreather technologies and to cultivate diver proficiency in the use of GUE approved rebreather configurations.


Applicants for a Rebreather course must:

  1. Submit a completed registration form, a medical history, and a liability release to GUE Headquarters.
  2. Be physically and mentally fit.
  3. Hold insurance that will cover diving emergencies such as hyperbaric treatment, e.g. DAN Master-level insurance or equivalent.
  4. Be a nonsmoker.
  5. Obtain a physician’s prior written authorization for the use of prescription drugs, except for birth control, or for any prior medical condition that may pose a risk while diving.
  6. Be a minimum of 21 years of age.
  7. Be a GUE Tech 2 certified diver.
  8. Have a minimum of 25 Tech 2 level dives beyond Tech 2 certification.


Course Content


The Rebreather course is normally conducted over five days; it requires at least eight dives and a minimum 40 hours of instruction, encompassing classroom, land drills and in-water work.

Rebreather Specific Training Standards

  1. Student-to-instructor ratio is not to exceed 6:1 during land drill or surface exercises; ratios cannot exceed 3:1 during any in-water training.
  2. Maximum depth of 100 feet/30 meters.


Training Materials

GUE training materials and recommended reading as determined by the course study packet received via online download after GUE course registration.


Academic Topics

  1. Introduction: GUE organization and course overview (objectives, limits, expectations)
  2. Purpose
  3. Common components of the rebreathers and how they function
  4. Inherent risks of rebreathers
  5. Rebreather operation, alarms, and warnings
  6. Oxygen risks: hypoxia, hyperoxia
  7. Decompression consideration while using semi-closed rebreathers
  8. Oxygen loading, potential drop, adjusted deco
  9. Equipment configuration
  10. Problem recognition and management
  11. The importance of instinctive physiological monitoring
  12. Pre-dive planning
  13. Post-dive procedures
  14. Need for continuing education and skill reinforcement


Land Drills and Topics

  1. Flow checks
  2. Manifold failures
  3. Gas addition failures
  4. Gas sharing


Required Dive Skills and Drills

  1. Demonstrate a safe and responsible demeanor throughout all training.
  2. Demonstrate proficiency in underwater communication.
  3. Demonstrate basic proficiency managing a rebreather configuration.
  4. Demonstrate reasonable proficiency with use of the rebreather during ascents, descents, and diving.
  5. Demonstrate good buoyancy and trim, i.e. approximate reference is a maximum of 20 degrees off horizontal while remaining within 3 feet/1 meter of a target depth.
  6. Must be able to swim at least 500 yards/450 meters in less than 14 minutes without stopping. This test should be conducted in a swimsuit and, where necessary, appropriate thermal protection.
  7. Must be able to swim a distance of at least 60 feet/18 meters on a breath hold while submerged.
  8. Demonstrate ability to manage gas failures, including valve manipulation, gas sharing, and regulator switching as appropriate.
  9. Recognize, assess, and review diving limitations.
  10. Skillfully demonstrate gas failure procedures, including valve manipulation, gas sharing, and regulator switching, as appropriate.
  11. Demonstrate the ability to manage a flooded rebreather while discharging excess water.
  12. Demonstrate the ability to diagnose and correctly respond to simulated rebreather problems.
  13. Demonstrate effective valve management.
  14. Demonstrate proficiency in removing/attaching stage and/or decompression cylinders while hovering horizontally.
  15. Demonstrate the ability to comfortably switch gasses while maintaining good trim and neutral buoyancy.
  16. Demonstrate proficiency in safe diving procedures, including assembly, vacuum and pressure tests, pre-dive preparations, pre-dive vacuum test, flow check, in-water activity, and post-dive assessment and breakdown.
  17. Efficiently and comfortably demonstrate how to donate gas to an out-of-gas diver while using the rebreather.
  18. Be able to comfortably demonstrate use, manipulation, and failures of the gas addition system.
  19. Demonstrate awareness of a team members’ rebreather function and a concern for safety, responding quickly to visual indications and dive partner needs during diving and failures.


Equipment Requirements


GUE base configuration as outlined in Appendix A, plus:

  1. Modified tank configuration as appropriate for GUE approved Rebreather
  2. Modified regulator configuration as appropriate for GUE approved Rebreather
  3. Bottom stage
  4. Two decompression bottles

Explore GUE Standards

Prior to the commencement of class, students should consult with a GUE representative to verify equipment requirements and appropriateness of any selected equipment.