GUE Rec 3

Recreational Diver Level 3 - Trimix Diver


Course Outcomes


The GUE Recreational Diver Level 3 course is a limited decompression course structured to prepare divers for deeper recreational diving while using sound equipment, efficient diving skills, and advanced breathing mixtures. Course outcomes include, but are not limited to: skill cultivation and refinement, knowledge of relevant physics and physiology, familiarity with the theory and practice of decompression, correct ascent procedures, the use of double back-gas tanks/cylinders, the use of Nitrox for decompression, the use of normoxic Helium (30/30 and 21/35) to minimize narcosis, CO2, gas density, and post-dive “nitrogen stress,” and the use of a single decompression cylinder for stage decompression techniques.



Applicants for a Rec 3 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 18 years of age.
  7. Have passed GUE Recreational Level 2 or GUE Fundamentals with at least a “recreational” pass.
  8. Have completed the GUE Doubles Primer course or be proficient in doubles with at least 25 experience dives.
  9. Have a minimum of 75 non-training dives.


Course Content


The Recreational Diver Level 3 course is normally conducted over five days, and includes eight dives and at least forty hours of instruction, encompassing classroom, land drills and in-water work.


Rec 3 Specific Training Standards


  1. Student-to-instructor ratio is not to exceed 6:1 during land drill or surface exercises; it cannot exceed 3:1 during any in-water training.
  2. Maximum depth of 130 feet/39 meters.
  3. No overhead diving.
  4. Dives should not be planned to incur more than 15 minutes of total ascent time as established by GUE’s DecoPlanner.
  5. Critical skills may only be performed up to a maximum depth of 30 feet/9 meters.


Required 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. Applied diving physics
  3. Applied diving pysiology
  4. Introduction to normoxic trimix
  5. Nitrogen narcosis
  6. Gas density
  7. Carbon dioxide
  8. Oxygen limitations
  9. Dive planning and gas management
  10. Decompression dynamics
  11. Understanding inert gas on-gassing and elimination
  12. Decompression theories
  13. Decompression practices while using nitrox
  14. Decompression planning using tables and DecoPlanner
  15. Decompression illness
  16. GUE Equipment configuration
  17. Dive planning and logistics


Land Drills & Topics


  1. Situational awarenenss
  2. Dive team order and protocols
  3. GUE-EDGE and Pre-dive drill
  4. Out of gas scenarios and touch contact
  5. Valve management including failure procedures
  6. Use of safety spools and lift bag
  7. Ascent and decompression protocols
  8. Gas switching protocol
  9. Unconscious/Toxing Diver
  10. Descent/Ascent Drill


Required Dive Skills & Drills


  1. Must be able to swim at least 300 yards/275 meters in less than14 minutes without stopping. This test should be conducted in a swimsuit and, where necessary, appropriate thermal protection.
  2. Must be able to swim a distance of at least 50 feet/15 meters on a breath hold while submerged.
  3. Demonstrate proficiency in safe diving practices; this would include pre-dive preparation, in-water activity, and post-dive assessment.
  4. Demonstrate awareness of team member location and a concern for safety, responding quickly to visual indications and dive partner requirements.
  5. Demonstrate proficiency in lift bag/surface market buoy deployment.
  6. Demonstrate good buoyancy and trim, i.e. approximate reference maximum of 30 degrees off horizontal while remaining within 5 feet/1.5 meters of a target depth.
  7. Efficiently and comfortably demonstrate how to donate gas to an out-of-gas diver in multiple gas-sharing episodes.
  8. Demonstrate three propulsion techniques. Students should demonstrate comprehension of the components necessary for a successful backward kick.
  9. Demonstrate proficiency during gas-sharing scenarios, including a gas-sharing horizontal swim and a direct ascent while managing decompression obligations.
  10. Demonstrate proficiency in the use of touch contact communication during out-of-gas situations.
  11. Demonstrate proficiency in the use of the primary light including passive and active communication.
  12. . Demonstrate proficiency with a single decompression cylinder.
  13. Demonstrate proficiency with valve-management by conducting a GUE valve drill.
  14. Demonstrate proficiency with proper ascent/descents, deep stops and safe gas switches.
  15. Demonstrate proficiency in surfacing an unconscious diver from depth.
  16. Demonstrate basic equipment proficiency and an understanding of the GUE equipment configuration.


Equipment Requirements

GUE base configuration as outlined in Appendix A, plus:
    1. GUE double tank configuration
    2. Primary and back-up lights
    3. Decompression cylinder
    4. Small argon regulator and bottle (if appropriate for local conditions)
    5. Back-up mask

Note: Prior to the commencement of class, students should consult with a GUE representative to verify equipment requirements. Whether or not a piece of equipment fulfills GUE's equipment requirement remains at the discretion of GUE and its instructor representatives. Participants are responsible for providing all equipment or for making provisions to secure all necessary equipment before the start of the course. In general, it is better for the student to learn while using his or her own equipment. However, students should exercise caution before purchasing new equipment to avoid acquiring substandard equipment. Please contact a GUE representative prior to making any purchases. Information about recommended equipment can be obtained from the equipment considerations section of GUE's web site.