Overhead Environment training. I have tried to detail below in each course what needs to be covered as for as agency standards go but be rest assured the aim is to go far beyond the minimum training requirements. If you have any questions please do not hesitate to contact me.

TDI - Technical Diving International was formed in 1995 by Bret Gillian a former Director of IANTD and is now the world’s largest technical diving agency offering all level technical courses from Nitrox to Mixed Gas Rebreather. TDI is the future of technical training.

TDI Advanced Wreck Diver

The objective of this course for divers wishing is to train the divers in the benefits, hazards and proper procedures for wreck penetration.

Student Prerequisites:
• Minimum age of 18
• Be certified as an Advanced open water diver • Show proof of at least fifty (50) logged dives. • Be certified as Basic Wreck or Cavern or equivalent

The student must complete the following skills during wreck dives. All dives should be conducted with a maximum depth no deeper than the certified student’s capabilities.

Land Drills
1. Proper deployment of guideline
2. Proper technique for following guideline
3. Use safety spool / reel in lost line procedures
4. Use safety spool / reel in lost buddy procedures
5. Proper technique for touch contact communication
6. Properly analyze all gas mixtures to be used.
7. Demonstrate adequate pre-dive planning
A. Limits based on personal and team gas consumption.
B. Limits based on oxygen exposures at planned depths for actual mixes.
C. Limits based on nitrogen absorption at planned depths for actual mixes.

In-water Drills
1. Demonstrate specialized propulsion techniques for an overhead environment
2. Deploy guideline with attention to immediate environment and conditions
3. Demonstrate lost line and lost buddy drills
4. Follow guideline (eyes open and eyes closed – or blacked out mask)
5. Air share with team member(s) while exiting confined space (eyes open and eyes closed – or blacked out mask)
6. Remove and replace mask while in contact with guideline
7. Demonstrate light and hand communications with team members
8. Demonstrate touch contact with team members
9. Simulate primary light failure and deployment of backup lights
10. Demonstrate correct techniques for staging deco/contingency gas outside wreck
11. Demonstrate proper procedure for isolating and switching a malfunctioning regulator (This drill should be conducted no deeper than 40 meters / 132 fsw)
12. Demonstrate ability to deploy a lift bag from depth as emergency ascent line
13. Demonstrate ability to deploy a lift bag from depth as alternative buoyancy device
14. Execute simulated emergency blue water ascent with marker deployment from staged stop below 6 meters (simulated or real live boating)
15. Demonstrate understanding of basic wreck layout and special considerations for navigating wreck
16. Deal with diver presenting signs of serious DCS at surface (simulated emergency evac.)
17. Properly execute the planned dive within all pre-determined limits.
18. Demonstrate the proper navigational techniques for the specific dive.
19. Demonstrate out of air sharing with long hose through a restriction.
20. Demonstrate the proper procedures for switching and isolating a malfunctioning regulator (This exercise shall not be conducted deeper than forty (40) msw) / one hundred thirty (130) fsw.
21. Deployment of lift bag or up line for decompression.
22. Silt-out procedures.
23. Follow line while sharing air.
24. Follow line with eyes closed while air sharing.

The following equipment is required for each student participating in the Advanced Wreck Course

1. Primary Cylinder(s)
A. Cylinder volume appropriate for the planned dive and student gas consumption rate.
B. Dual valve, double manifold or independent doubles.
C. Labeled in accordance with TDI Standards.
2. Travel or Decompression Cylinders as required by site conditions.
3. Regulators
A. Primary and primary redundant required on all primary breathing cylinders.
B. Submersible pressure gauges are required on all primary cylinder(s).
C. A contingency use long hose second stage should be designated and appropriately rigged to facilitate air sharing at depth if necessary.
4. Buoyancy Compensator(s) adequate for the open water environment.
5. Back-up Depth and Timing Devices.
6. Air decompression computers allowed for use as depth and timing devices.
7. Light Systems
A. Primary.
B. Back-up.
8. Ascent reel with lift bag/surface marker buoy or up-line
A. Adequate for the planned maximum depth.
B. Minimum of eleven (11) kg / twenty five (25) lb. Lift.
9. Exposure suit adequate for the open water environment.
10. Two (2) Line Cutting Devices.
11. Underwater Slate.
12. Reels
A. Primary penetration reel.
B. Safety reel.
13. Options that the instructor may require
A. Submersible dive tables.
B. Bail-out cylinder with regulator.
C. Jon-line.
D. Slate, compass, surface signaling device (flare, strobe, etc.)

 Download the full TDI Course Outline as pdf Document

TDI Cavern Diver

This is the intermediate level certification course for divers wishing to utilize This course is designed to develop the minimum skills and knowledge for cavern and overhead environment diving within the limits of light penetration; in addition outlines specific hazards associated with cave diving. The Cavern Diver Course in not intended to provide instruction for cave diving environments. The objective of this course is to train divers in the proper planning, procedures, techniques and hazards of cavern diving.

Course Structure and Duration

Water Execution:

Four (4) Cavern dives with a total bottom time of eighty (80) minutes conducted at two (2) different sites.
1. The minimum number of classroom and briefing hours is six (6).
2. Course must be conducted over a minimum of 2 days.

During The Course You will learn the following:

1. How to properly deploy a guideline.
2. How to properly follow a guideline.
3. How to touch contact communicate
4. How to correctly deploy directional markers

The student must perform the following S-drill and skills during all dives:

1. Demonstrate adequate pre-dive planning.
2. Equipment check and gear matching.
3. Bubble check.
4. Demonstrate specialized propulsion techniques.
5. Demonstrate proper buoyancy control.
6. Demonstrate proper body posture.
7. Demonstrate proper stress analysis (detection and management).

The student must perform the following in-water skills during cavern dives:

1. Properly deploy a guideline.
2. Properly follow a guideline with eyes open and closed (simulating loss of visibility).
3. Air share with a buddy with eyes open, following the guideline.
4. Air share with a buddy with eyes closed and use touch contact, following the guideline.
5. Remove and replace mask while in contact with guideline.
6. Demonstrate light / hand -signals and touch contact.
7. Explore cavern.
8. Referencing as back-up navigation.
9. Anti-silting techniques.
10. Simulate a primary light failure, and deploy back up light and follow guideline
11. If diver uses a duel valve system, air/gas valve management

Required equipment – Info

Primary cylinder - volume appropriate for planned dive and student gas consumption. Students are permitted to use double cylinders, but would be limited to the 1/6 air rule.
2. Regulator with pressure gauge and alternate air source. Although not required, it is suggested one regulator be mounted on a hose approximately two (2) meters / seven (7) feet of length.
3. Buoyancy Compensator with power inflator.
4. Exposure suit adequate for cavern environment.
5. Mask and fins - NO snorkel.
6. Line cutting device.
7. Safety reel with a minimum of thirty (37) meters / one hundred twenty five (125) feet of guideline.
8. One (1) primary cavern-diving reel with length appropriate for intended dive.
9. Two (2) battery powered lights, each with burn time suitable for the planned dive time.
10. Computer or watch (bottom timer) and depth gauge.
11. Slate or wet notes and pencil.
12. Submersible dive tables or backup dive computer (recommended)
13. three (3) directional line arrows
14. Weight system

Student Prerequisites:
• Minimum age of 18 or 15 with parental consent
• Show proof of a minimum certification as a certified diver with a minimum of twenty five (25) dives
• This course is run over three days if taught stand alone (could be combined with the Intro Cave Diver course)

 Download the full TDI Course Outline as pdf Document

TDI Intro to Cave Diver

This course is an introduction to the basic principles of cave diving utilizing a single primary guide line.
Introductory cave diving is the second level in the development of safe techniques for cave diving, directly building upon the cavern diver course. This introduction to cave diving is not intended to train divers for all facets of cave diving. The objective of this course is the perfection of skills taught in the cavern diving program with additional techniques and procedures required for elementary cave dives.

Course Structure and Duration

Water Execution:

Minimum of four (4) single guideline cave dives with a total bottom time of one hundred (100) minutes conducted at two (2) different sites.

TDI allows instructors to structure courses according to the number of students participating and their skill level.

1. The minimum number of classroom and briefing hours is four (4).
2. Course must be taught over 2 days.
3. If this course is combined with a cavern diver course it is a minimum of 3 days and a total of 8 dives and 180 bottom time minutes.

During The Course You will learn the following:

1. How to properly deploy a guideline.
2. How to properly follow a guideline.
3. Use of safety reel in lost diver procedures.
4. Use of safety reel in lost line drill.

The student must perform the following S-drill and skills during all dives:

1. Demonstrate adequate pre-dive planning.
2. Equipment check and gear matching.
3. Bubble check.
4. Demonstrate specialized propulsion techniques in varying types of flow.
5. Demonstrate proper buoyancy control.
6. Demonstrate proper body posture.
7. Demonstrate proper stress analysis (detection and management).

The student must perform the following in-water skills during cave dives:

1. Properly deploy a guideline.
2. Properly use line markers.
3. Properly follow a guideline with eyes open and closed (simulating loss of visibility).
4. Air share with a buddy with eyes open, following the guideline.
5. Air share with a buddy with lights off, eyes closed and use touch contact, following the guideline.
6. Remove and replace mask while in contact with guideline.
7. Demonstrate light / hand -signals and touch contact.
8. Conservation and awareness techniques.
9. Referencing as back-up navigation.
10. Demonstrate adequate anti-silting techniques.
11. Simulate a primary light failure, and use back light to exit the cave.
12. Demonstrate lost line and lost diver drills.

Required equipment – Info

1. Primary cylinder (s) - volume appropriate for planned dive and student gas consumption.
2. Dual-orifice (Y) or (H) closed valve or dual valve manifold.
3. Two independent first and second stage regulators. One regulator equipped with a long hose at a recommended minimum length of two (2) meters / seven (7) feet.
4. Submersible pressure gauge.
5. Buoyancy Compensator with power inflator.
6. Exposure suit adequate for diving environment.
7. Mask and fins - NO snorkel.
8. Line cutting device.
9. Three (3) battery powered lights – one (1) primary and two (2) back-ups, each with a with burn time suitable for the planned dive time.
10. Safety reel with a minimum of thirty (37) meters / one hundred twenty five (125) feet of guideline.
11. One (1) primary cave-diving reel with length appropriate for intended dive.
12. Computer or watch (bottom timer) and depth gauge.
13. Slate or wet notes with a pencil
14. Submersible dive tables or backup dive computer.
15. Three (3) directional line arrows.

Student Prerequisites:
• Minimum age of 18 or 15 with parental consent
• Show proof of a minimum certification of Cavern Diver or equivalent, with a minimum of twenty five (25) dives
• This course is run over three days if taught stand alone

 Download the full TDI Course Outline as pdf Document

TDI Cave Diver

This course is designed to teach This course is the third (3rd) stage of training in the series of TDI’s cave diver development programs.
Advanced cave dive planning, the practical execution of different types of cave systems and scenarios divers encounter are presented. This cave diving course is not intended to prepare divers for evaluating all facets of cave diving. The objective of this course is to expand and critique previous skills accomplished in the Cavern and
Introductory Cave diving programs. Emphasis is placed upon dive planning and skill perfection through actual cave penetration.

Course Structure and Duration

Open Water Execution:

1. Eight (8) cave dives are required with a minimum accumulated bottom time of two hundred forty (240) at three different sites.
2. At least one (1) of these sites should be a location not utilized in training during the Cavern or Introductory Cave Courses
3. For divers entering the cave program without Cavern / Introductory Cave Diving certification, sixteen (16) cave dives with four hundred twenty (420) minutes of total bottom, (not including decompression time are required).

Course Structure:

1. The number of classroom and briefing hours is six (6).
2. Course must be taught in no less than four (4) days.
3. If combined with Cavern and Intro to Cave diving, course must be 7 days long.

During The Course You will learn the following:

1. How to properly deploy a guideline.
2. How to properly follow a guideline.
3. Use of safety reel in lost diver procedures.
4. Use of safety reel in lost line drill.

The student must perform the following S-drill and skills during all dives:

1. Demonstrate adequate pre-dive planning.
2. Equipment check and gear matching.
3. Bubble check.
4. Demonstrate specialized propulsion techniques in varying types of flow.
5. Demonstrate proper buoyancy control.
6. Demonstrate proper body posture.
7. Demonstrate proper stress analysis (detection and management).

The student must perform the following in-water skills during cave dives:

1. Properly deploy a guideline.
2. Properly use directional and non directional line markers.
3. Properly follow a guideline with eyes open and closed (simulating loss of visibility).
4. Air share with a buddy with eyes open , following the guideline.
5. Air share with a buddy with lights off and eyes closed and use touch contact, following the guideline.
6. Remove and replace mask while in contact with guideline.
7. Demonstrate light / hand -signals and touch contact.
8. Conservation and awareness techniques.
9. Referencing as back-up navigation.
10. Demonstrate adequate anti-silting techniques.
11. Simulate a primary light failure, and use back light to exit the cave.
12. Demonstrate lost line and lost diver drills.
13. Demonstrate to use of reels to perform jumps and gaps required in circuits and traverses to maintain a continuous guideline to open water.

Required equipment:

The following equipment is required for each student:
1. Dual cylinders, volume appropriate for planned dive, student gas consumption.
2. Two independent first and second stage regulators. One regulator equipped with a long hose at a recommended minimum length of two (2) meters / seven (7) feet.
3. Submersible pressure gauge.
4. Buoyancy Compensator with power inflator.
5. Exposure suit adequate for diving environment.
6. Mask and fins - NO snorkel.
7. Two (2) line cutting devices.
7. Three (3) battery powered lights – one (1) primary and two (2) back-ups, each with a with burn time suitable for the planned dive time.
8. Safety reel with a minimum of thirty seven (37) meters / one hundred twenty five (125) feet of guideline.
9. One (1) primary cave-diving reel with length appropriate for intended dive.
10. Computer or watch (bottom timer) and depth gauge.
11. Slate or wet notes with a pencil
12. Submersible dive tables or back up dive computer.
13. Three (3) directional line arrows.
14. One (1) non- directional line marker.
15. Gap reel with fifteen (15) meter / fifty (50) feet of guideline.

Student Prerequisites:
• Minimum age of 18
• Have a minimum certification of Introductory Cave Diver or equivalent with a minimum of fifty (50) dives

 Download the full TDI Course Outline as pdf Document