SDI Sidemount Diver Course

Standard scuba configuration mounts your cylinder on your back. Sidemount configuration clips one or two cylinders to your sides instead, hanging along your body from shoulder to hip. It changes how you move through the water, how you manage your gas, and how you access your valves, and for a growing number of recreational divers it is simply a more comfortable way to dive.

The configuration originated in cave diving, where a streamlined profile matters for fitting through tight passages. In recreational diving, the same setup offers better horizontal trim, valve access you can see and reach without twisting, and two independent gas sources that function as built-in redundancy. For divers who want a path toward technical diving, sidemount is also foundational to how advanced configurations work.

The SDI Sidemount Diver course teaches you to set up, configure, and dive a sidemount system safely from the ground up.

What the Course Covers

Equipment: Configuration, Options, and Setup

Sidemount gear is more configurable than backmount, and the right setup depends on your body, your diving, and your goals. The course covers cylinder options for sidemount use, regulator configurations specific to sidemount, BCD and harness options and how they differ from backmount systems, proper weighting for sidemount trim, and how to configure the full system for your body before you get in the water.

Gas Management with Independent Cylinders

Sidemount divers manage two independent gas sources rather than one. That changes how you plan a dive, how you monitor your gas throughout, and how you switch between cylinders during the dive. The course covers gas management protocols specific to sidemount, how to perform gas switches at depth, and how to track consumption across two cylinders simultaneously.

S-Drills and Gas Sharing

An S-Drill is a standardized gas-sharing practice drill specific to sidemount diving. It simulates a catastrophic gas loss and trains you to share gas with your buddy using the sidemount configuration. The course covers S-Drill technique alongside broader gas-sharing protocols and emergency procedures for loss of gas from one or both cylinders.

Attaching Cylinders in All Conditions

One of the most sidemount-specific skills is attaching your cylinders in different environments before and during a dive. The course covers cylinder attachment out of the water before entry, on the surface standing on a shallow bottom, on the surface in water too deep to stand, and at depth after a dive has started. Each scenario requires a different technique and all are practiced in the course.

Communication and Water Entries

Sidemount affects how you move on the surface and how you enter the water. The course covers hand signals used in sidemount diving, shore entry procedures with sidemount cylinders, and boat entry techniques that account for the different profile sidemount creates at the surface.

In-Water Skills

The course includes open water dives. Required skills include:

• Full dive plan for a sidemount dive
• Equipment test and check before entry
• Site familiarization and descent to planned depth
• Gas management across independent cylinders throughout the dive
• Monitoring depth, time, and air consumption on a slate
• Buoyancy control in sidemount configuration
• Cylinder attachment in all four conditions: out of water, surface shallow, surface deep, and at depth
• Gas switches between cylinders
• S-Drill with buddy
• Safety stops and controlled ascent

Gear and Equipment

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

Sidemount harnesses are a different matter. A sidemount harness is fitted specifically to your body, with adjustments to the D-ring positions, bungee length, and attachment points that take significant time to get right and are personal to the individual diver. Using a harness that is not fitted to you makes the course harder and the diving less effective. For that reason, we strongly recommend that students come to the course with their own harness. We carry and fit sidemount harnesses in the shop. Stop by or call us at (480) 881-4013 before you enroll and we will get you fitted so the harness is ready to go for your first session.

Students are required to own their own mask, fins, boots, and snorkel. All other standard scuba rental gear including BCD, tanks, weights, wetsuit, and computer is included in the course. If you'd like to purchase any equipment, we carry a full selection in the shop and all students enrolled in a course receive a discount on purchases during enrollment.

Who Can Enroll

The SDI Sidemount Diver course is open to certified SDI Open Water Scuba Divers or equivalent. Minimum age is 15 with parental consent, 18 without.

Counts Toward the SDI Advanced Diver Rating

The SDI Sidemount Diver certification counts as one specialty credit toward the SDI Advanced Diver Development Program.

Frequently Asked Questions

What is sidemount diving?

Sidemount diving is a configuration where one or two cylinders are clipped to the diver's sides rather than mounted on the back in the standard backmount setup. The cylinders hang along the body from shoulder to hip, which changes the diver's trim, improves valve access, and provides two independent gas sources as built-in redundancy. It originated in cave diving and has become popular in recreational and technical diving.

What are the benefits of sidemount diving?

Three main benefits. First, improved horizontal trim -- cylinders at the sides rather than on the back allow a more natural horizontal body position in the water. Second, easier valve access -- both cylinder valves are in front of the diver and reachable without twisting. Third, redundancy -- two independent gas sources mean a failure in one cylinder does not end the dive.

Is sidemount diving hard to learn?

The biggest adjustment is managing two independent gas sources simultaneously and learning to attach cylinders in different conditions including at depth. The configuration itself, once set up correctly, feels natural to most divers within the first few dives. Getting the harness fitted and configured correctly before the course makes a significant difference to how quickly the skills develop.

What equipment do I need for sidemount diving?

At minimum, your own sidemount harness. Sidemount harnesses are fitted specifically to your body and take time to dial in, so using a loaner harness that is not sized to you slows down the course significantly. Dive Arizona provides sidemount cylinders and regulators. We sell and fit sidemount harnesses in the shop - call us at (480) 881-4013 before you enroll to come in for a fitting.

Does the Sidemount Diver certification count toward SDI Advanced Diver?

Yes. The SDI Sidemount Diver certification counts as one of the four specialty credits required for the SDI Advanced Diver Development Program.

Is sidemount a step toward technical diving?

Yes. Sidemount configuration is foundational to many technical diving setups, including cave diving, where a streamlined profile is necessary for tight passages. Divers who want to move toward TDI technical diving programs will find sidemount skills directly applicable to that path.

Ready to Try Sidemount?

Call us at (480) 881-4013 before you enroll to come in for a harness fitting. Getting that right first makes everything else 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!