Sidemount scuba is simply a well polished approach to gear configuration for cave diving in unusually tight conditions. It employs innovation and discipline to produce an arrangement of scuba unlike any the typical diver is accustomed to.
Sidemount Cave Diving is quickly gaining popularity as an alternate method of gas management. Instead of carrying a redundant primary air source on the back, Sidemount utilizes the versatility of the advanced cave diver to split the typical twin cylinders and relocate them under each arm. In doing so, the cave diver minimizes direct physical contact with the cave, and is able to proceed through unusually tight passages.
The low vertical profile of the cave diver’s air supply allows the scuba cylinders to be easily manipulated, and carried in a less cumbersome manner. The absence of large scuba cylinders on the back helps to avoid damage to critical life support equipment from careless strikes to the cave ceiling.
Even in conditions that don’t necessarily call for the specialization of Sidemount, a diver may choose to incorporate such techniques simply as an added means of cave conservation, advanced gas management or simple comfort.
The boundary between distinct limestone layers are what cave divers call bedding planes. Bedding planes provide an excellent place for underwater passageways to form. Unfortunately, such passageways, while wide, are often not tall enough to permit divers with back-mounted cylinders to pass. Cave divers responded to this challenge by developing the technique of sidemounting.
Additionally, some divers who suffer from back problems or disabilities that affect use of their legs find that sidemounting provides a welcome alternative to the use of heavy, back-mounted doubles.
For many years, it was impossible to purchase off-the-shelf equipment for sidemounting. For a long time, the terms best used to describe sidemount equipment included words such as home made and jury rigged. Fortunately, these days are over.
Then designing the Transpac II, Lamar Hires also developed a system for modifying the Transpac harness and Trek Wings air cell so that the same harness can be used for sidemounting, as well as for backmounted singles and doubles. Switching back and forth between these configurations takes only a matter of minutes.
(Articles by Lamar Hires and Bill Rennaker)