Technical Refresher Dive
Our facilities manager and resident technical dive-master Christos Kardana recently conducted a technical refresher for a big blue tech client, covering key skills essential whilst technical diving. Conducted in a similar fashion to that of refresher common in the recreational diving industry, a variety of skills where demonstrated and completed.
The confidence to complete essential safety skills is paramount whilst diving in general, but even more so in the world of technical diving where you take on challenging dive environments and profiles. The sheer bulk and number of equipment necessary, combined with the effects of narcosis at depth and the ceilings imposed by decompression diving, emphasises the importance of executing these skills with efficiency and confidence. This is further exacerbated by the usual task loading of ‘mission diving’ common in the technical world of diving, whether it is search and recovery or simply adding a video camera and the pressure of capturing certain footage whilst at depth.
A standard technical refresher here at Big Blue Tech is conducted in a confined water environment – ocean or swimming pool- entailing equipment assembly, pre-dive and in water checks, followed by S-drills and key skills. Equipment assembly involves complete set-up of a technical twin set rig, as well as deco tank set-up and gas analysis, demonstrating correct use of an oxygen analyser and tank management and labelling. A short briefing is conducted covering the skill breakdown and dive signals followed by kit up and correct front stride entry into the water -right hand palm securing mask and primary regulator, with left forearm bracing left and right deco tanks. Buoyancy and bubble checks are completed followed by key technical dive skills:
S-drill: acting as receiver and donor for out of air drill, in a controlled manner while maintaining position in the water column.
Gas shutdown: completing full gas shutdown of all posts managing multiple failures, showing awareness in switching from primary to alternate air source and vice versa accordingly. Reaction to catastrophic gas loss and securing failure should be ideally achieved in less than 30 seconds.
Regulator recovery: retrieving long hose primary air source, with and without the use of alternate air source (necklace).
Staging cylinders: while maintaining buoyancy, deco cylinders are staged and received achieving competence both on the ‘fly’ and statically in the water column.
BCD removal: removing and re-donning BCD, demonstrating awareness in hose management and deco cylinder staging.
Tired diver tow: acting as donor and receiver of air source (long hose) towing a tired or unconscious diver at depth ensuring victim regulator is secure with one hand and controlling victims movement via securing manifold with other hand.
Simulated gas switch: switching to deco cylinder gas, noting depth, mix and teammate awareness while changing blend, both face-to-face and individually on the fly.
The above drills are an essential combination of skills required whilst tech diving whether in a team or solo. Through repetitive circuits during the refresher we aim to achieve correct execution whilst maintaining a high level of awareness for teammate and the environment. Additional drills can be added, depending on the divers comfort and experience such as breathing from deco cylinders staged at multiple locations at shallow depth, improving muscle memory and confidence in relation to quick gas switching.
A technical refresher in a confined environment can be of vital importance to an individual re-entering the world of technical diving, whether it be for a few fun dives or one considering further education. Furthermore, for one who will be diving and using equipment through a dive centre, it provides the perfect opportunity to test and become accustomed to a new set of kit and procedures -regardless of past experience or amount of time spent out of the water- before re-immersing yourself in the world of decompression and extended range diving.
Big Blue Tech is currently working on short skill circuit videos, which will be posted in the near future.