Certified divers learned to do predive safety checks during training, but do they perform one every time they dive? It is one of the easiest ways to prevent oversights, gear malfunctions and forgotten pieces of equipment. But predive safety checks often aren’t as thorough as they should be.
A predive safety check commonly follows the initials BWRAF, which stands for BCD, Weights, Releases, Air and Final check. Instructors use a variety of mnemonics to help students remember this list, including “Burger With Relish And Fries,” “Breathing Water Really Ain’t Fun” and “Begin With Review And Friend.” This content is similar to other predive check acronyms such as SEA BAG (Site survey, Emergency planning, Activity planning, Buoyancy, Air, and Gear and go) or ABC (Air, Buoyancy, and Clips and releases). Whichever way you remember to do a predive check, follow your training, and be systematic and consistent.
Chaleco de flotabilidad The first step is to confirm that your buoyancy compensator device will hold air. Check that the low-pressure inflator hose is snugly connected to the BCD and that the inflate and deflate buttons don’t stick to prevent buoyancy issues or uncontrolled ascents. Fill your BCD with air by testing the power-inflate and oral-inflate mechanisms. Pull each dump valve to ensure it is functioning correctly and not sticking open. Look at your buddy’s configuration and make sure that the toggle for the shoulder dump valve isn’t stuck under the shoulder strap, which could cause the diver to inadvertently pull open the dump valve, leading to buoyancy problems. Make sure the tank band securely holds the cylinder in place. If you are not familiar with your buddy’s BCD, learn about its inflation and deflation mechanisms in case of an emergency.
Pesos: This step is essential for ensuring the proper management of an emergency. You and your buddy should be familiar with each other’s weight configurations for ease of removal in the water if needed. Show your buddy where you keep weights — a belt, integrated pockets, trim pockets or ankle weights. If you use pockets, gently pull on them to ensure they are securely fastened. Make sure you have your weights before you enter the water.
Liberación This is arguably one of the most critical steps in the predive safety check. In case of emergency, you must know how to remove your buddy’s equipment. If you’ve never seen their setup, removing their BCD for the first time in the middle of an emergency could be difficult. Even if you are familiar with your buddy’s equipment, it is still a good idea to review it.
Show your buddy how to release your weights, especially if you use an integrated system. Your buddy should be prepared to manage the type of release you use, such as clips, rip cords, gravity release pouches or fabric fasteners. Discuss ways to release your equipment, including shoulder straps, chest strap and cummerbund. Make sure the tank band is tight enough to keep the cylinder in place. Review where you keep your octopus, gauges or other hoses — such as for a drysuit — and how to release them.
Aire: Asegúrate de que el aire esté completamente abierto antes de entrar al agua. Muchos buceadores miran rápidamente su manómetro sumergible (SPG) para ver si marca que está lleno, pero esto no garantiza que la válvula de la botella esté abierta. A veces, las personas abren el aire mientras se preparan, comprueban que la botella está llena y luego lo cierran sin liberar la presión de las mangueras purgando uno de los reguladores. Una manguera presurizada hará que el SPG indique que la botella está llena, pero cuando respires todo el aire de la manguera en una o dos respiraciones, podrías quedarte sin aire de repente.
Most training agencies no longer recommend turning the handwheel a quarter-turn closed due to fatalities surrounding this practice. Novice divers and even some dive professionals can become confused about which direction to turn the handwheel, causing them to turn someone’s air only a quarter-turn on as opposed to a quarter-turn off. Modern cylinder valves do not succumb to wear and tear as older models did, so it is best to fully open your cylinder valve.
Otro error común es no respirar tanto por el regulador principal como por el octopus antes de entrar en el agua. Hay varias razones para hacerlo. La primera es asegurarse de que respiran con facilidad, especialmente si se utiliza equipo alquilado. La segunda razón tiene que ver con el funcionamiento interno de un regulador de segunda etapa. Dentro del regulador hay un diafragma flexible sobre una palanca móvil. Cuando se inspira, el efecto de succión flexiona el diafragma hacia la palanca para liberar aire. Al espirar, el diafragma se flexiona en la otra dirección, liberando la palanca y deteniendo el suministro de aire. El botón de purga se encuentra en la parte superior de esta palanca, por lo que al pulsarlo se está presionando manualmente la palanca. Es importante asegurarse de que el regulador responde a la respiración, no al tacto.
The third reason is to taste the air from your cylinder to ensure that it isn’t bad. Contaminants such as gas fumes or oil may have an oily taste, oily smell or bad odor. If you think you have bad air, alert the dive staff and do not use the cylinder.
Cuando respires por primera vez con cada regulador, exhala primero y luego inhala. Podría haber residuos o incluso pequeños animales escondidos dentro del regulador, y exhalar primero te ayudará a asegurarte de que no entren en tu boca.
Antes de entrar en el agua, comprueba de nuevo que el aire está completamente abierto y considera la posibilidad de respirar profundamente varias veces con el regulador mientras observas el manómetro. Si el aire está completamente abierto, la aguja se mantendrá estable. Si el aire está cerrado pero sigue habiendo presión en las mangueras, la aguja bajará drásticamente con cada respiración. Si el aire está solo parcialmente abierto, la aguja bajará y volverá a subir con cada respiración.
Chequeo Final: Make sure you have all your miscellaneous equipment such as a mask, snorkel, fins, signaling devices and camera equipment ready. Streamline your equipment by securing any loose or dangling hoses or pieces of gear. Ensure that your computer is set to the correct gas mixture and paired to your cylinder if it is air-integrated. Defog your mask, and perform a head-to-toe check to make sure you do not forget anything else. Have your buddy check as well to make sure you didn’t miss anything.
La complacencia y saltarse la comprobación de seguridad previa a la inmersión o la comprobación del compañero son factores totalmente evitables en los accidentes de buceo. Realice todas las comprobaciones antes de cada inmersión.
© Alert Diver — Q3/Q4 2020