Purpose

The IANTD Technical Diver / Normoxic Tri-Mix course is designed to increase diver proficiency to depths of 200' using Tri-Mix to reduce narcosis. The student will be introduced to Run-Times as well as producing custom, mixed gas dive tables. A higher level of understanding and proficiency in all aspects of diving to 200' will be attained. This is an essential and mandatory step before progressing to the Full Tri-Mix course.

Prerequisites

• Must meet the IANTD General Course Prerequisites for Technical Diver programs

• Must be qualified as an Advanced Nitrox diver with a minimum of 100 logged dives of which at least 30 were deeper than 90'

• Must be a minimum of 18 years of age

• Be a non-smoker

• Entry into course by Instructor approval

Training Materials

IANTD Technical Encyclopedia and Technical Workbook

Duration

The IANTD Technical Diver / Normoxic Tri-Mix course includes fifteen hours of academics generally taught in five , three hour sessions as well as eight dives completed over four days.

Course Content

The IANTD Technical Diver / Normoxic Tri-Mix course cumulatively includes a minimum of forty hours of instruction designed to provide a working knowledge of extended range diving. A strong emphasis is placed on extended exposures and on their associated considerations (gas consumption, DCS, oxygen toxicity and thermal concerns). Eight dives will be conducted including five skill dives and three experience dives.

Academic Topics

• IANTD organization

• Course Standards and Procedures

• Course completion requirements

• Dive logistics and planning

• Equipment

• Accident analysis

• The art of breathing

• Technical oxygen

• Inert gas narcosis

• Carbon dioxide

• Carbon monoxide

• Decompression theory

• Psychology for Technical Diving

Surface Drills and Skills

• Reel, spool and guideline use

• Gas switching procedures

• Communications

• Ascent procedures

In-water Skill Requirements

• Review procedures for air sharing, valve drills, gas failures, regulator switching and bottle removal and replacement

• Become proficient with the following propulsion techniques: modified flutter, modified frog, modified dolphin and standard shuffle kicks

• Deploy a lift bag in less than 1 1/2 minutes while hovering stationary

• Swim a distance of 75' without wearing a mask

• Remove and replace stage cylinder while at rest and while swimming

• Simulate BCD failure by utilizing dry suit or lift bag for emergency buoyancy control

• Various out of air scenarios

• Demonstrate effective deployment of backup light in under 30 seconds

Course Limits

• IANTD General Program Limits

• Maximum student to instructor ratio is not to exceed 4 to 1

• Maximum depth of 200'

• Only one decompression cylinder may be used in this course

• All dive must utilize at least 20% oxygen with an END (equivalent narcotic depth) of no greater than 100'

Equipment Requirements

• Twin, manifolded diving cylinders to carry sufficient gas supply for completion of dive following the rule of thirds

• A 7' hose with backup around neck attached with bungee necklace

• Pressure gauge (this should be a 2" gauge on approximately a 24" hose)

• Buoyancy control device ( should be a single "wing" style BCD)

• Mask and fins

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

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

• Appropriate exposure suit for 48 degree water temperature

• External dry suit inflation bottle and regulator

• Slate and pencil or Wet Notes

• Cutting tool. Small knife or medical shears

• Compass

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

• Primary light (preferably a canister style light)

• Backup light

• Lift bag (preferably a 50lb. bag)

• Small reel or spool (75'-100' of line)

• 1 40 cu.ft. deco cylinder and 1 80 cu.ft. deco cylinder

• 2 decompression gas regulators with pressure gauges

• Surface marker buoy