1.4 General Training Limits

The following limits apply to ALL levels of training (course specific limits can be found in the relevant sections).

1.4.1 PO₂ Limits

All dives are to maintain a working PO2 of no greater than 1.4ATA and a resting PO₂ of 1.6ATA +/- .05. Oxygen partial pressures are adjusted downward, according to the demands made by diving conditions with an average working PO2 of approximately 1.2ATA. “Resting dives” are defined as dives during which it is not reasonably expected that a diver will have to expend any unusual amount of energy, for example during decompression.

1.4.2 END Limits

No dives are to be planned to exceed an Equivalent Narcotic Depth (END) of 100 feet/30 meters; END is established by the following equations

END(m) = (((1− fHe) × (depth in ATA)) −1) × 10 m
END(ft) = (((1− fHe) × (depth in ATA)) −1) × 33 ft
Where END is the equivalent narcotic depth in meters or feet and DATA is the depth, expressed in ATAs.

1.4.3 Breathing Gas Requirements

All dives must begin with “minimum gas.” Minimum gas is defined as the volume needed for two divers sharing gas to reach the surface or another breathable gas supply.

1.4.4 Parameters for Critical Skills

Drills or skills that involve loss of visibility; loss of lights; simulated out-of-gas scenarios; simulated manifold failures; and rescue techniques involving assisting panicked divers, convulsing divers and unconscious divers, are to be considered critical skills.

1. Critical skills must first be conducted in a confined-water setting, after which instructors can progressively increase the depth and/or penetration in which these are executed.
2. Mask removal is restricted to confined water; under such training conditions, only the trainees themselves are allowed to remove their masks, at the prompting of their instructor. Mask removal is not permitted in any overhead environment (save decompression).
3. For the DPV program the following skills are considered critical: out of gas, towing a diver and dealing with a runaway DPV.
4. “Air gunning,” a form of simulating manifold failure, is restricted to Technical, Cave, and Rebreather and DPV level 2 courses.
5. Under no circumstance should critical skills be conducted in delicate cave environments where damage to the environment may occur.
6. GUE instructors are prohibited from turning off student cylinder valves (right, left, or isolator) EXCEPT in the event of a real regulator or manifold failure where turning off the relevant valve would be required. However, during rebreather training, instructors may interrupt gas addition to the rebreather.

1.4.5 Dual Qualification

Another agency’s qualifications may be awarded to a student—as a dual qualification—only if the student has met GUE standards and has been awarded full GUE qualification. The student can then receive both a GUE qualification card and the equivalent qualification of another agency.

1.4.6 Issuing Qualification under Other Agencies

Qualification from another agency may not be issued instead of a GUE qualification. This means that if a trainee does not warrant full qualification under GUE’s standards and procedures, no qualification from another agency can be awarded in its stead.

1.4.7 Teaching and Rebreathers

GUE instructors may not teach GUE courses while on a rebreather. The only exceptions are when training rebreather instructors during an instructor training course (ITC), or when critical-skill testing is complete during rebreather classes.

1.4.8 Buoyancy Considerations

Some diving environments (e.g., shallow caves) permit divers with no buoyant lift (e.g., failed buoyancy compensator) to exit along a floor of reasonable depth; other environments, because of their depth, do not. Divers should account for such conditions and seek to ensure that their systems enable them to return safely to the surface in the event of a loss of buoyancy or a low-on-gas situation.

1.4.9 Conservation

As part of GUE's commitment to global environmental conservation, Appendix A details recommended areas for simulated zero-visibility drills, required by all GUE Cave programs.

1.4.10 Decompression Parameters

GUE recognizes that events may conspire to result in decompression sickness, despite the care exercised by those involved. Nonetheless, GUE requires that, when training, GUE instructors follow conservative decompression schedules and evaluate decompression schedules using GUE’s DecoPlanner as a standard. Decompression times during training should approximate the time indicated by DecoPlanner when using either gradient factors of 30/85 when using the Buhlmann algorithm, or on a conservatism setting of 2 when using the Variable Permeability Model. These profiles will be known as Unadjusted Decompression profiles. These may be adjusted in a pragmatic manner to enable simpler in-water implementation. Dives where DecoPlanner does not indicate any decompression requirement longer than one minute at any single stop depth are known as Minimum Decompression dives. These should be implemented by slowing the ascent rate in the final half of the ascent.

1.4.11 Course Size

GUE courses must not be run with only one student. The only exception to this stipulation involves instructor training courses, which may be conducted with one candidate.

1.5 General Diving Skills

All GUE courses must ensure proficiency in the following diving skills; proficiency is measured by a final grade of 3 (satisfactory) or better when demonstrating the skill. Course-specific requirements including any deviation from a particular skill will be listed under the appropriate course section. The standards below do not bind GUE Recreational Diver courses or GUE Fundamentals courses, which are governed by a more restricted skill sets (see relevant sections).

1. Demonstrate proficiency in safe diving practices; this would include pre-dive preparation, in-water activity, and post-dive assessment.
2. Demonstrate awareness of team-member location and a concern for safety, responding quickly to visual cues and dive partner requirements.
3. Efficiently and comfortably demonstrate how to donate gas to an out-of-gas diver in multiple gassharing episodes.
4. Be able to comfortably demonstrate at least three propulsion techniques that would be appropriate in delicate and/or silty environments; one of these kicks must include a backward kick.
5. Demonstrate a safe and responsible demeanor throughout all training.

All GUE instructors are encouraged to exceed minimum training standards when by doing so they are promoting the best interests of the student. Instructors are actively encouraged to deny qualification to students when students have not met the standards of the certification level they are pursuing to the satisfaction of the instructor.

1.6 General Prerequisites for All GUE Courses

All GUE courses have the following prerequisites (any additional prerequisite, as well as any deviations from the following, will be listed under the specific course section):

1. Must submit a completed registration form, complete with medical history, and liability release to GUE Headquarters.
2. Must be physically and mentally fit.
3. Must hold insurance that will cover diving emergencies such as hyperbaric treatment e.g. DAN Master-level insurance or equivalent.
4. Must be a nonsmoker.
5. Must obtain a physician’s prior written authorization for the use of prescription drugs, except for birth control, or for a prior medical condition that may pose a risk while diving. A partial list of such conditions may be found on GUE’s medical history form. Conditions that pose a risk to students while diving require a physician’s written approval to dive; this information must be disclosed to their GUE instructor before the onset of training. Physician clearance for a specific condition is valid for one year from the date it is given, assuming there are no further changes to the student’s medical conditions. Physician clearance to dive under a specific medical condition does not obligate GUE or a GUE representative to clear a trainee for diving; this remains at the sole discretion of the instructor.