Hi Mark. I appreciate your continuing efforts to educate divers & increase diving safety. Regarding the "quarter turn", I see that you weren't sure when that old procedure was dropped, even attributing it to DAN perhaps "a year ago". Institutions are notoriously slow to change their recommendations. It takes a long time for all of the litigation lawyers to finally agree! The necessity of "quarter turn" was applicable only to the very old pillar valves which have not been made since the late 1960's. It wasn't long after that when it became obvious that the practice was not only unnecessary but could be hazardous. Checking back on my own RU-vid channel, Alec Peirce Scuba, which I know you watch, Thank You, you will find a video about that subject. In fact, I think it was posted on both the Tech Tips playlist AND the Vintage Scuba playlist of the channel. That was a good many years ago. I have been teaching the "No Quarter Turn" for many years which is particularly interesting because I taught the "Quarter Turn" rule for several years before that. Things change and a clear understanding of the mechanics & physics of scuba gear can help divers adjust to those changes. "That's the way my instructor did it!" is NOT a good basis for a safe diving career. Thanks again for your efforts Mark and remember, I'll be watching!!! With admiration, I remain, Alec Peirce.
send up a dsmb whenever you can, how else are you going to get experience to deploy it i found the dm appreciate it so you can practice when you add enough air it seriously takes off and happens fast practice practice practise
#AskMark Hey Mark, thanks for answering my question! I actually had to tow a buoy for the first time this week, and I couldn't agree more - it sucked! If you wouldn't mind a follow up question - if you are regularly diving in a site that requires towing a buoy, is it beneficial to invest in one of those torpedo shaped ones? Do they actually make the task easier?
I trained sidemount with a Hollis SMS 75, from the dive center, wich in theory was disegned to be used as one cylinder back mount and as a sidemount system, but to be honest, I hate it , I didn´t feel confortable. After I finished the course, I bought a Razor 2.5 , and it was a completely different history, I´m a lot more confortable and it impoves my trim, as is more customizable than the SMS 75. My advise is the same as mark, if you want to do sidemount invest in a sidemount BCD. The BCD is also a tool for an specific task, is like you want to unscrew an star screw with a flat screwdriver.
"Back in the day"... here in the States, we Great Lakes divers used what was known as a "Farmer John wetsuit". It was a 1/4" (6mm-ish) sleeveless suit with a 1/4" long sleeve jacket with either a beavertail or short legs. This would increase the insulation around the torso with a full 1/2" of neoprene for extra warmth. I have noticed that these are not very popular anymore, but the Farmer John's were toasty in the 70's to the 90's. So two layers of neoprene do have the insulating properties of its total thickness.
I live in a landlocked city (Birmingham) and am looking to start my diver training. I am fortunate enough to have multiple BSAC clubs within fairly close proximity. You have previously talked about choosing instructor over training agency, but what would you recommend looking for in choosing a BSAC club to join and train with? Thanks! #askmark
#askmark Hi Mark I plan to buy a DSMB, so I wonder how tall it should be, I have seen they are were between 120cm upto 180cm, I have seen some shorter then 100cm, but those wouldn't make sense to me. Thanks. Ben
#askmark So my wife and I just did a dive in Maldives where we could have used some reef hooks. In researching to purchase some, we see doubles and singles but no dual singles. Any reason? Why couldn't we make a dual single (for portability and hooking angle variability plus the benefit of dual hook fixation)? Also we were thinking of making some w straps instead of cord (the ones used for portable hammocks) that way we can adjust the length. Also what if we used titanium instead of SS? Has anyone used cobalt chrome in seawater? Anyone have any input on these ideas?
I can attest to the fact that it doesn't take a whole lot of depth with a 1/4 turn. The one time I did not check my own tank because it was checked by someone I trusted, it turned out that the tank was only 1/4 turn on. I made it down about 40ft (12m) before the regulator cut off with 1/4 breath. One of the worst headaches I've ever had not to mention something that would cause complete panic in most divers leading to very dangerous outcomes
I'm guessing that layering suits over each other would be more restrictive (ala famer John) and not provide as much insulation as the oversuit would likely compress the one under it and compress the cavities that are insulating you. Would be interesting to know for sure and see a study of it!
Just use the school stuff till you get a few dives in then if you are able get a package deal from the shop many times you get a better price than buying separately not trying to out do everyone else
Rental equipment is usually included in the training. Just use that to see if you really enjoy diving enough to commit more money to it. I wouldn't bother with package deals early on. The first purchase afterward is usually your own wetsuit. For other stuff, the dive shops will just try to sell you whatever they have and not necessarily what you need. You will probably need to rent/borrow a fair bit of different equipment to learn what you prefer and want to do first.
Instead of spending three minutes on a safety stop, is it just as good to go up to 5 meters (or 16,4 feet, for those weird imperialists 😉) for the last three minutes on your way to the exit point? I don’t see why it shouldn’t. #askmark
No Quarter turn back? Really? My son is a Open Water diver, I am Rescue and am an ex techie (I don't have the time for the training dives and cannot justify the money for the gas and servicing of all the regs and cylinders any more) On one of his first dives I was told by my son, in no uncertain terms that we no longer turn it back a quarter of a turn so that the Dive Guide can check that the cylinder is open. Ok I said, and watched him turn his tank all the way on. I turned mine one quarter turn back. At the end of the dive he could not turn it off. This required taking the knob off and using a spanner to get it going again. Rented tank, in service, no other issues, I never leave my tank all the way open, THE BUDDY CHECK should stop going in with air off, and if not I always take a couple of breaths as I am checking below me on the descent, so when I check my air, it would be obvious. If you stick to the procedures that we are all taught, this should not be an issue.
Not to mention that you should train to reach your valves and manipulate them in the water, if you lock it out, it can make it hard to get started. You ideally need to shut them off and turn them on at any time.
