Purpose

The IANTD Recreational Tri-Mix course is designed to train divers in the use of gas mixtures containing helium to reduce the effects of narcosis at depths not to exceed 100' or students previous certification level. The recreational Tri-Mix program may be conducted as a single course or combined with a variety of other courses.

Prerequisites

• Must meet the IANTD General Course Prerequisites

• Must be qualified as an Advanced Open Water diver or equivalent as well as a Nitrox diver or take in conjunction with Recreational Tri-Mix

• Must be a minimum of 15 years of age with parent approval

• Be a non-smoker

Training Materials

IANTD Recreational Tri-Mix Student Manual

Duration

The IANTD Recreational Tri-Mix course

Course Content

The IANTD Recreational Tri-Mix course cumatively includes a minimum of ten hours of instruction designed to provide a thorough understanding of the benefits and concerns regarding the use of helium in breathing gas mixtures. The program covers the use of gas mixtures containing 28% - 40% oxygen and helium concentrations that yield no more than a 80' END (Equivalent Narcotic Depth). Two experience dives will be conducted.

Academic Topics

• IANTD organization

• Course Standards and Procedures

• Course completion requirements

• Recreational Tri-Mix advantages and concerns

• Equipment Configuration

• Figuring personal gas consumption

• Physiology of Recreational Tri-Mix diving

• Inert gas narcosis

• Carbon Dioxide

• Decompression sickness

• Recreational Tri-Mix gas calculations

• Accident management

• Dive planning

• Helium

Surface Drills and Skills

• Gas analysis and dive planning, including the use of tables and discussions on the use of dive computers will be covered

• Configure dive equipment in a streamlined and efficient manner

• Gas sharing techniques

In-water Skill requirements

• Demonstrate proper buoyancy control

• Demonstrate proper body posture and anti-silting techniques

• Perform gas sharing drill while having the out of gas diver swim 40' to the donor without breathing

• Perform one gas sharing drill on ascent

• Demonstrate the deployment of a backup light in less than 30 seconds

Course Limits

• IANTD General Program Limits

• Maximum student to instructor ratio is not to exceed 5 to 1

• Maximum depth 130' and no greater than 80' END (Equivalent Narcotic Depth)

• No dives requiring mandatory decompression stops exceeding three minutes

Equipment Requirements

• Diving cylinder(s) to carry sufficient gas supply for completion of dive; 1/2 plus 200 psi for no-stop dives

• Alternate second stage or redundant gas supply

• Pressure gauge

• Buoyancy control device (BCD)

• Mask, fins and snorkel

• Means of monitoring depth and time. Depth gauge and bottom timer or a dive computer

• Dive table must be used backup computer or for control of the dive

• Appropriate exposure suit for 48 degree water temperature

• Slate and pencil or Wet Notes

• Cutting tool. Small knife or medical shears

• Compass

• Surface alert device (whistle, Dive Alert etc...)