Before entering the water, you can breathe fine from your primary regulator. You could mistakenly close the valve and open it only a quarter turn instead of the other way around. Now imagine that you get confused about whether you opened or closed your valve. You reach back and turn your cylinder valve all the way open before entering the water. Imagine this scenario: Your valve is closed, and when you put your primary regulator in your mouth before entering the water you discover that you cannot draw a breath. These are reported incidents associated with the quarter-turn back, but we can safely assume that a significant number of such incidents go unreported. While the quarter-turn-back practice is still present in other industries to prevent valve damage and ensure that valves do not stick open, the dive industry is moving away from this practice because people unfortunately keep getting injured.ĭivers Alert Network ® has recorded 13 incidents since 2013, including one that resulted in a fatality and another that required a hospital stay (see “An Emergency Ascent Just in Time” by Christina Hepburn in the Spring 2017 Alert Diver). Less force is needed to fully close or open the valve, and valves are now less prone to leaking or sticking open. Modern valve design, however, protects both the valve stem seal and valve seat. Overtightening the valve when opening squeezes this piece, causing damage over time. The damage will cause it to leak, leading the user to overtighten it more. This seal is easily damaged if the valve is overtightened when closed. To compensate for the leak, divers would close the valve even more tightly, which would cause an even greater leak over time. In both cases the valve would start to leak either through the handwheel or out of the valve outlet. The second cause of damage was from closing the valve too tightly, which could affect a different seal located at the end of the handwheel’s inner part, called the valve seal or insert, by pressing it onto the seat. Divers feared that the valve would stick open and delay any ability to shut it off in an emergency. When forced beyond fully open, a seal inside the valve near the handwheel, called the valve stem seal or packing, would become damaged over time from being squeezed against the valve bonnet nut. Overtightening older valves could cause damage in two ways. In the past, valve designs were not as sophisticated as they are today. Have you ever wondered why this procedure was recommended? Is this practice still necessary? Using proverbs adds color to your writing or speech.“Turn on your cylinder, and then close it one-quarter turn.” Many divers have heard this instruction during and after their scuba certification classes. It could refer to a figurative habit or a physical habit. “Old habits die hard” is a famous saying that means it’s difficult to stop a habit that’s been going on for a long time. only to give up sooner! ( India Today) Learn More Proverbs Every New Year, people pick resolutions: losing weight, quitting smoking, eating healthy, waking up early, going running, etc. Old habits die hard and we all tussle with forming virtuous habits. Man, old habits die hard! I make the same resolutions every year, try them for a few days, then give up and go back to my old ways of eating horrible food and never exercising.He still treats his employees like robots and refuses to make any changes at the company to make us happy. Old habits die hard, and my boss is proof of that.I’m sorry, I can’t stop eating hot sauce on everything.Even though I’ve told her a dozen times, she still goes to bed with her makeup on. My sister is living proof that old habits die hard. To this day, they still spend their mornings with a cup of coffee and an old-fashioned newspaper that they pay extra for.
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