“This week we push past recreational dive limits by learning how to side mount scuba dive. Paired along side deco procedures and advanced nitrox, the side mount course unlocks new areas of the deep.“
Garrett Clement
Scuba sets are mounted alongside the diver, below the shoulders and below the hips, as opposed to on the back, in a technique known as sidemount diving equipment. Since it makes it easier to access cylinder valves, provides simple and dependable gas redundancy, and makes tank removal simple when needed, it was originally designed as a configuration for advanced cave diving. Technical wreck diving penetration divers were also aware of these advantages for working in tight spaces.
With multiple diver certification agencies offering recreational and technical level sidemount training programs, sidemount diving is becoming a more and more popular specialty training for recreational diving as well as gaining popularity within the technical diving community for general decompression diving.
Benefits and Flexibility
There are certain advantages to sidemount diving in terms of equipment versatility. Unlike manifolded twin sets for back-mounted use, which enable the traveller to do challenging or overhead environment dives without having to seek twin cylinder sets, cylinders appropriate for sidemount diving are typically readily accessible for rental. Transporting a single diving cylinder, especially by hand, may be less physically demanding when diving in distant locales. Air travel can be made easier and more affordable using side mount harnesses since they can be lighter and less cumbersome than back-mounted options.
Accessibility
The sidemount diver can view and immediately access the regulators and tank valves of their cylinders, unlike back-mounted cylinders. This makes it possible to identify and solve problems more quickly and accurately without the need for “behind the head” shut-down drills, which call for a higher degree of joint and suit flexibility as well as the capacity to recognize and properly handle equipment that is out of sight.
Low Profile
When using a sidemount diving arrangement, the diver can fit through narrower spaces than they might with back-mounted cylinders since the cylinders are positioned under their armpits and in line with their body. When penetration diving, the diver’s only physical restrictions are the weight of their diving suits and bodies, which they can remove from their tanks and put in front of them to fit through extremely narrow openings and passageways. It’s not always possible to streamline your swimming stroke to reduce drag.
Safety
Improved efficiency and speed of critical cylinder shut-down procedures are achieved by increased accessibility to regulator first-stages and cylinder valves. This also enables immediate identification of gas loss and gives the diver rapid access to alternative contingency procedures, such as switching regulators between cylinders, manually operating a cylinder valve to control gas flow through a free-flowing regulator, or allowing breathing directly from the tank valve.
By mounting the cylinders at the diver’s sides, the first stages of the regulator and valves are less vulnerable to collision and abrasion damage, as well as unintentional shutdown due to roll-off against a ceiling. Moreover, it considerably lessens the chance of entanglement behind the diver, which is the hardest to fix.
Comfort
Certain divers can attest that sidemount diving provides more stability and simpler trim and control while submerged. In addition, sidemount equipment is said to be less physically taxing to carry and enter than back-mounted doubles, particularly when working from a small boat or a choppy shore entry.
The diver can eliminate lugging twinned cylinders by having the capacity to attach, remove, and replace cylinders while submerged in water. For divers with limited mobility or discomfort in their shoulders or backs, the decreased physical strain involved in regulator shut-down processes is a huge advantage.
Redundancy of Gas
Typically, technical divers have employed a redundant gas supply system consisting of independent back-mounted cylinders or isolation-manifolded cylinders. Gas provided by friends or very modest bailout ‘pony cylinders’ or ‘ascent bottles’ for out-of-air emergencies have historically been the only options available to recreational divers. These cylinders, which can be carried at the chest or fixed to the main cylinder, frequently cause issues with streamlining and stability while only offering insufficient oxygen for emergency ascent. Similar to back-mounted twins, sidemount diving with two equal-sized cylinders assists with stability and streamlining problems and can guarantee the maintenance of an acceptable redundant reserve of air.
In the event of a regulator failure and shut-down, just access the entire gas supply with back-mounted manifolded cylinders. A significant leak at the manifold, however, would rob the diver of at least half of the remaining gas supply because the manifold itself generates additional potential o-ring failure spots. When sidemounted, independent cylinders offer more dependable gas redundancy and, if the diver is proficient in the additional skills needed, increase access to all residual gas by allowing regulators to be switched between cylinders or feather breathing.
Convenience
Complicated hardware is not needed for sidemount. It just requires basic rigging and may be completed using the most widely accessible rental cylinders (Al 80s). A basic wrench and one or two low pressure port plugs can generally be used to reconfigure the regulators if the diver is also renting them. For travel, the buoyancy compensator and harness can be small and lightweight.
Problems
Depending on which alternative configuration is compared, sidemount diving may result in greater drag when swimming and increase the job stress on the diver. Due to the absence of the back gas set, the diver’s head may be more susceptible to impact with the overhead. The usage of a helmet could lessen this.
Because sidemounting shifts the weight from the spine to the hips and shoulders and keeps the back less rigid, it is frequently beneficial for divers who have back issues. Moreover, sidemount divers gain from a greater gas supply, which might enable longer dives. By reducing water resistance, tucking the cylinders under the arms may improve kick efficiency.
Don or Doff
Because they can choose to wear or take off their single or double cylinders whether in the water or on the surface, sidemount divers typically have more alternatives than backmount divers when it comes to donning and doffing because of personal preference and environmental factors. Single cylinders can be lowered and raised with a rope, or given to and from a friend on land who is not carrying gear. Cylinders can be readied for hand-off below the surface in rougher conditions and swiftly passed to the boat crew, or they can be linked to a line for retrieval at a later time.
Many PADI technical-level instructors copied the sidemount diving speciality course that PADI teacher Jeff Loflin created since it was so well-liked. As a result, PADI began to offer standardized sidemount diving programs for both technical and recreational divers, making sidemount diving a popular and practical choice for both groups of divers. Sidemount training is also offered at different levels by other organizations as ANDI, IANTD, SSI, TDI, UTD, and ISE (Innerspace Explorers).