TDI Sidemount Diver Course

The SDI Sidemount specialty introduces sidemount configuration and gets you diving it. The TDI Sidemount Diver course takes the same setup and builds on it at a technical level. Gas management becomes more complex when your cylinders carry dissimilar volumes. Propulsion technique becomes more precise when you are navigating confined spaces. The psychological side of technical diving -- the discipline, the decision-making, the awareness of your own stress response -- gets addressed directly rather than left as something you figure out over time.

This course is built for divers who have already decided sidemount is their configuration and want to use it to a technical standard. It covers everything from equipment options and gas matching procedures through S-drills, lift bag deployment, and diving in tight or confined spaces. Sidemount cylinders and regulators are provided by Dive Arizona. Bring your own harness -- if you do not have one yet, call us before you enroll and we will get you fitted.

Who This Course Is For

• SDI or TDI certified divers who have completed SDI Sidemount or have existing sidemount experience and want to develop technical-level skills
• Divers pursuing the technical track who want sidemount as their primary configuration
• Certified divers interested in expanding into confined space or cave diving where sidemount technique is foundational

What the Course Covers

Gas Matching and Independent Cylinder Management

When both sidemount cylinders carry the same gas and similar volumes, management is straightforward. Technical sidemount diving often involves cylinders with dissimilar volumes, and matching gas consumption across them requires deliberate technique. The course covers gas matching procedures for cylinders of different sizes, how to plan and track consumption across independent gas supplies throughout a dive, and gas switching with and without a mask -- a skill that needs to be solid before it ever gets tested under real conditions.

Propulsion Techniques

Technical diving requires a broader propulsion vocabulary than recreational diving. Each technique serves a specific purpose, and using the wrong one in the wrong environment silts out visibility, damages the bottom, or wastes gas. The course covers and requires demonstration of:

• Frog kick: the foundational technical kick, efficient and silt-safe on flat terrain
• Modified frog kick: a shorter-amplitude version for tighter spaces
• Modified flutter kick: for controlled movement near the bottom or in current
• Backwards kick: for retreating without turning around in confined spaces
• Helicopter turn: stationary rotation for precise directional changes
• Hand pulling: used when fin use is not appropriate for the environment

Psychological Considerations of Technical Diving

Technical diving creates stress conditions that recreational diving rarely produces. Confined spaces, reduced visibility, complex gear, and the weight of managing multiple systems simultaneously all affect how a diver thinks and responds. The course covers the psychological side of that environment directly: how to recognize stress in yourself and your buddy before it affects performance, the decision-making framework technical divers use under pressure, and what the mental discipline of technical diving actually requires day to day. This is not a soft topic, it is one of the areas where technical divers fail when they skip it.

Equipment Configuration and Selection

The course covers sidemount cylinder options and how to evaluate them, regulator selection and configuration for sidemount, buoyancy compensator and harness options at the technical level, and proper weighting for trim in a sidemount setup. Light and hand signals specific to sidemount team diving are also covered, along with problem-solving procedures for sidemount-specific gear failures.

Confined Space Diving, Conservation, and Back-Referencing

Sidemount configuration is widely used in confined spaces including cave passages and tight wreck sections where a backmount setup would not fit. The course covers the specific techniques required for diving in tight or restricted environments, conservation practices that protect fragile underwater environments from contact and silt disturbance, and back-referencing, which is the habit of periodically checking behind you to maintain awareness of what is between you and the exit.

In-Water Skills

The course includes open water dives. Required skill demonstrations include:

• All six propulsion techniques demonstrated to standard in open water
• Neutral buoyancy hover at a fixed position without hand or foot movement
• Proper trim maintained throughout descent, bottom phase, and ascent
• Unclipping and attaching sidemount cylinders while maintaining trim and buoyancy
• Gas switches with and without a mask while maintaining position in the water column
• Independent cylinder gas management throughout the dive
• Conservation, awareness, and back-referencing technique demonstrated throughout
• Lift bag deployment from depth
• S-drill with buddy specific to sidemount configuration
• All land drills performed safely and efficiently prior to in-water work

Who Can Enroll

The TDI Sidemount Diver course is open to certified SDI Open Water Scuba Divers or equivalent. Minimum age 18. Prior SDI Sidemount experience is not required but is useful -- if you have not dived sidemount before, consider starting with the SDI Sidemount specialty first.

Gear and Equipment

Sidemount cylinders and regulators are provided by Dive Arizona for use during the course.

A sidemount harness is a different matter. A sidemount harness is fitted specifically to your body, with D-ring positions, bungee routing, and attachment points that take significant time to configure correctly for the individual diver. Using a harness that is not fitted to you slows down the course and produces worse outcomes in the water. We strongly recommend that students come to the TDI Sidemount course with their own harness. We sell and fit sidemount harnesses in the shop. Call us at (480) 881-4013 before you enroll and we will get you sorted before the first session.

Students are required to own their own mask, fins, boots, and snorkel. If you need any other equipment, we carry a full selection in the shop and all students enrolled in a course receive a discount on purchases during enrollment.

Frequently Asked Questions

What is the difference between SDI Sidemount and TDI Sidemount?

The SDI Sidemount specialty is a recreational course that introduces sidemount configuration, basic cylinder attachment skills, gas management, and S-drills. The TDI Sidemount Diver course covers the same configuration at a technical level: gas matching with dissimilar cylinder volumes, the full suite of technical propulsion techniques, confined space diving, conservation and back-referencing, and the psychological considerations of technical diving. TDI Sidemount is the appropriate course for divers pursuing the technical track or planning to use sidemount in more demanding environments.

What propulsion techniques are required for TDI Sidemount?

Six techniques are required: frog kick, modified frog kick, modified flutter kick, backwards kick, helicopter turn, and hand pulling. Each serves a specific purpose in technical environments. The frog kick is the foundational technical kick for open water. The backwards kick allows retreat without turning in confined spaces. Helicopter turns enable precise directional changes without forward momentum. Hand pulling is used when fins would cause damage or disturbance to the environment. All six are demonstrated to standard as part of the in-water skills requirement.

What is gas matching in sidemount diving?

Gas matching is the process of managing gas consumption across two independent sidemount cylinders so that both cylinders are used at a planned rate throughout the dive. When cylinders carry dissimilar volumes, matching becomes more complex -- you cannot simply switch cylinders at equal intervals. The course covers the planning and in-water technique required to match gas across cylinders of different sizes.

Do I need my own sidemount harness for the TDI Sidemount course?

Yes, it's strongly recommended you own your own harness. A sidemount harness is fitted specifically to your body and takes significant time to configure. Dive Arizona has a small number of harnesses available, but training on a harness that is not fitted to you produces worse results. We sell and fit sidemount harnesses in the shop, call us at (480) 881-4013 before you enroll to come in for a fitting.

What does the psychological considerations section cover?

The psychological considerations section covers how technical diving creates stress conditions that recreational diving rarely does, confined spaces, complex gear, multiple systems to manage, and how experienced technical divers recognize and manage that stress. Topics include stress recognition in yourself and your buddy, decision-making frameworks under pressure, and the mental discipline that technical diving requires. It is treated as a skill to develop, not a personality trait you either have or do not.

Is prior sidemount experience required to enroll?

Not formally. The minimum certification is SDI Open Water Scuba Diver or equivalent. That said, if you have never dived sidemount before, the SDI Sidemount specialty is a useful starting point before jumping into the TDI course. Call us at (480) 881-4013 and we can talk through which course makes sense based on where you are right now.

Ready to Dive Sidemount at a Technical Level?

Call us at (480) 881-4013 before you enroll to come in for a harness fitting. Getting that right first makes everything in the course go faster. We are open Monday through Saturday 11am to 6pm and Sunday 11am to 5pm, at 18618 S 186th Way, Queen Creek, inside The Shooting Range.

For more information and to see course standards, click here!