Sidemount, the Fastest Growing Segment in Diving

by Dori Phillips:
sidemount diver

So what is sidemount and why is it so popular? Simple answer really, it’s a new way to approach gear configuration to expand diving accessibility. That is not to say sidemount diving is actually all that new, but rather the techniques and the commercialization of the equipment are new. Early cave exploration, scientific diving expeditions, and wreck divers were using the techniques in small teams with highly modified (often with duct tape) versions of traditional scuba gear.

Today, most people come to me for sidemount classes and advice based upon one of the following motivators:

  • desire to go farther, longer, deeper and do not want to use doubles
  • site logistics prevent the use of doubles
  • physical constraints
  • desire to dive with rebreathers and/or stages
  • it’s something new to try

The TDI course embraces all of these desires. Before the actual TDI Sidemount course, the use of sidemount techniques was only taught during technical dive classes or by special request. The use of double cylinders on the back was, and in some places is still, considered the norm for technical divers or those simply wanting more gas and redundancy. Today, the craze of sidemount is both practical and inspiring as the thinking diver emerges. Standards exist for a reason, but the nuances of the application to the environment, the diver and team is what keeps people engaged and interested, even debating.

Sidemount is simply tanks “on the side” instead of (or in addition to) on your back. A few of my friends call this technique “sidebars” when they have a tank on their back. Anyone can strap on a tank, however as many of us have witnessed over the years, trial and error until you figure it out is not the safest or most practical approach to learning a skill, especially not in diving applications. The positioning of tanks along the side of the diver’s body completely changes their trim profile. Valves are more accessible, body position shifts, the regulator hoses are adjusted and the BCD provides lift from above instead of underneath the weight of the tanks. All the core gear is fundamentally the same as a back mounted tank diver, but the configuration and techniques change. These subtle adjustments are where the gear heads love to geek out and instructor guidance is paramount!

Ok, so how hard can it be? It’s not really – but it takes training and practice, plus my favorite trademark phrase, “Think it through seriously” (yes, acronyms are awesome). Sidemount steps outside of the mindset, “You must do it exactly this way!” and introduces the always entertaining instructor response “it depends”. This is a huge part of why sidemount is so popular, we have options!

So let’s look at my sidemount configurations, yes – plural. We’ll start warm water simple and grow in complexity. In warm water around the world, AL80 tanks are easy to obtain and easily strap on to each side of my lightweight harness with wing. Each tank has a first stage, one second stage, pressure gauge on a short hose and a low pressure inflator. If it is a shallow reef dive and the boat or resort has AL40s, maybe I will use those. They are the equivalent of an AL80 but with redundancy and extremely minimal impact in the water. If I were actually a better photographer, that would be a perfect rig for such activities. In the continental US or Europe, I’ll likely use AA85 or HP100 tanks for weight and trim in salt water drysuit and a little extra gas. Now let’s consider why diving my rebreather requires the sidemount configuration. I need at least one bailout and strapping tanks to my front is just plain awkward. The sidemount approach puts even large bailout tanks out of the way and streamlined, therefore most rebreather students start with a sidemount course or configuration sessions.

The new way of looking at this approach to diving provides a logical way to mitigate concerns found with diving doubles, avoids huge double tanks on the back and opens diving access in more locations. Loading and filling cylinders is more manageable and physical barriers break down for those not built with a 6’4” tall 180 lb frame. Manufacturers are pouring out varieties of sidemount equipment and more instructors are embracing the options. This is a fun and inspiring way to look at diving, just remember to “think it through seriously” and start with a little guidance via demos and the TDI Sidemount course.

Dori Phillips is an active TDI Instructor Trainer and founder of Get Out and Dive, a dive training and events organization. Her diving has taken her to amazing places around the world from Canada to Antarctica, Thailand to the Galapagos and many points along the way. In addition to dive training, she is an organizational consultant and has supported various manufacturers, retailers, academic institutions and small businesses. Dori loves to dive and share with those looking to learn, from beginner to cave diver and open or closed circuit, her patience with any student who is willing to make the commitment has been recognized by students over the years. Embrace her “think it through seriously” mindset – and you’ll have a blast!