Turning the tank valve back half-a-turn often confuses divers and can inadvertently make breathing difficult at depth. This diver kept a cool head and ascended on her buddy\u2019s alternate air source.<\/p>\n\n\n\n
While diving with my dive buddy in Florida, I noticed that upon each inhalation the needle of my submersible pressure gauge (SPG) fluctuated. The needle dipped down with each breath before returning to the correct psi reading for my tank. I continued diving while keeping a close eye on the gauge and, upon reaching a depth of approximately 55 feet, (16 meters) it suddenly became very difficult for me to breathe. I looked at my SPG mid-breath and saw the needle drop down to zero psi, and it did not readily move back up. I felt like there was no more air available to me even though I knew there was at least 1200 psi (80 bar) in my tank. I signaled \u201cout of air\u201d to my buddy, and used her alternate regulator. We made a controlled ascent to the surface, and I was not injured. Upon inspecting my gear, I realized that instead of turning my tank all the way on and half a turn back, I had turned it all the way off and half a turn on. Upon reaching a depth below 33 feet (10 meters), I had experienced inadequate air pressure delivery from my tank to my regulator because the tank was barely on and could not continue to deliver the same volume of air at the increased pressure.<\/p>\n\n\n\n
It must have been disconcerting to suddenly be unable to breath at 55 feet (16 meters) depth. This diver kept a cool head, signaled \u201cout-of-air\u201d to her buddy, secured the alternate air source and made a controlled ascent. This is exactly what is taught in entry-level diver courses worldwide.<\/p>\n\n\n\n
Los d\u00edas en los que necesit\u00e1bamos girar la v\u00e1lvula media vuelta hacia atr\u00e1s han quedado atr\u00e1s, pero todav\u00eda algunos instructores ense\u00f1an a los buceadores a hacerlo. \u00bfPor qu\u00e9? La forma m\u00e1s segura de asegurarse de que dispone de gas suficiente para cualquier inmersi\u00f3n es abrir la v\u00e1lvula de la botella hasta el fondo y, a continuaci\u00f3n, mirar la SPG mientras respira un par de veces.<\/p>\n\n\n\n
If your needle does not move then your valve must be open and if your needle goes down towards \u2018Zero\u2019 then your valve must be closed. If you are in the habit of turning it back half-a-turn then, like this diver discovered, you might have enough gas to breath normally at the surface but you could find yourself short of breath at depth. Remember, the safest way is to turn your tank valve all the way open or all the way closed.<\/p>\n\n\n\n
Peter Buzzacott, MPH, Ph.D.<\/p>","protected":false},"excerpt":{"rendered":"
Girar la v\u00e1lvula de la botella media vuelta hacia atr\u00e1s suele confundir a los buceadores y puede dificultar inadvertidamente la respiraci\u00f3n en profundidad. <\/p>","protected":false},"featured_media":0,"template":"","dan_diving_incident_keyword":[],"class_list":["post-1728","dan_diving_incidents","type-dan_diving_incidents","status-publish","hentry"],"acf":[],"yoast_head":"\n