DEPTH Blog

We recently caught up with Asser Salama, author of the new release, Deep Into Deco: The Diver's Decompression Textbook. Asser is a technical diver and instructor, is founder of Tech Diving Mag and developer of Ultimate Planner decompression planning software. He has a bachelor’s degree in engineering and a master’s degree in business administration. A software developer with an interest in decompression modeling, Salama plans to implement computational algorithms based on credible research papers to prevent some pioneering work from fading into academic obscurity. 

Last week we released the first video in a new series on preventing diver fatalities. The second video in the series is now available!
In the second video, we discuss two types of common surface related injuries to divers - those that occur during the entrance to a dive site, and boat related injuries.

Drysuits provide the greatest form of passive thermal protection for the diver. They are designed as one piece suits with a waterproof zipper for entering and exiting and have attached boots and seals at the diver’s wrists and neck to provide a dry internal environment. The suits are normally designed so a wide variety of insulating undergarments may be worn beneath them. These undergarments trap a layer of air providing the primary protection against cold. Too much air trapped in the drysuit can create buoyancy problems because the air forms a “bubble” that will move inside the suit, but some air is needed in order prevent the suit material from compressing and catching skin in the folds and causing a suit squeeze. A suit “squeeze” can be uncomfortable but is avoidable by adding a small amount of air to remove any suit wrinkles.

Basic underwater navigation by means of simple observation or use of a compass and depth gauge remains a fundamental and essential skill for all divers. For most short excursions, these are the only instruments needed. Even when using advanced navigation instruments, basic navigation skills provide an important backup.

The term “sinus” can mean any channel, hollow space, or cavity in a bone, or a dilated area in a blood vessel or soft tissue; most often sinus refers to the four, paired, mucus-lined air cavities in the facial bones of the head. The same kind of membrane lines the sinuses and nose, so nasal infections spread easily to the sinuses. In sinusitis, mucous membranes inflame and swell, closing sinus openings and preventing infected material from draining. If nasal inflammation, congestion, deformities, or masses block sinus openings, the sinus lining swells and inflames, absorbing pre-existing gas that forms negative pressure. When blockage occurs during descent, the relative vacuum in the sinus increases the risk of damage. Hemorrhage into the sinus and then into the divers mask may occur.

An experienced open-circuit diver was trying the “latest, greatest” rebreather during an introductory dive experience. After a few minutes of cursory instruction, she entered the water and began her grand adventure. Descending gradually to 15 fsw (5 msw), she kept close watch on her gauges.