What's the most unpopular benign/non-polarizing opinion you hold re: diving?

[ReefHound]

Actually, the best and smartest thing is that all divers should be testing all tanks for % as well as CO. It should be taught to everyone at all levels. I have seen people on boats thinking they're diving air, but actually have 32 or 36. That would potentially suck if you break MOD significantly.

This. I work weekends on a liveaboard where we bank 32% and fill in place with long whips, 6 for nitrox and 4 for air. Nitrox divers must analyze and fill out a log before every dive. Air divers do not. The whips are marked quite differently and it's rare for a filler to hook one up wrong and I'm not aware of an instance where they did not realize it on their own and have to drain the tank and refill. But the possibility exists. But the potential is there for an air diver to get 32% as much as for a nitrox diver to get air.

I've never understood why the industry is so adamant about nitrox divers analyzing every tank for exact mix and air divers expected to trust their tanks to be air.

 

[drrich2]

On the other hand, EAN 32 seems to be far & away the most common nitrox mix, you mentioned that on that live-aboard you banked 32%, and with a MOD around 111 feet, it should in theory only become a concern if the divers get below that MOD. How often do rec. divers drop below 111 feet for any substantial period on most boat trips? What are the odds of a bad outcome in those cases where it happens?

Basically, I'm coming at the issue like this. If all across the U.S. we arbitrarily knocked 5 mph off the speed limit most everywhere, we might save some lives. But at some point, we look at the costs involved (not just money, but time, frustration, user preference), and decide hey, we are just plain not going to do that.

Point: In theory, it's a potential risk. In real world practice, does it rise to the level of being worth the cost/bother to mess with for most people most of the time?

If an op. were partial pressure blending nitrox and getting variable fill %'s, that could be a different situation. I'm assuming banked 32 from that example.

Richard.

 

[rddvet]

Point: In theory, it's a potential risk. In real world practice, does it rise to the level of being worth the cost/bother to mess with for most people most of the time?
.

You've just given the two most common and stupidest reasons people don't analyze their gas: laziness and cheapness.

One day you may eventually come across a bad tank. You'll either find out when you find it with an analyzer or when you have a really bad experience.

Too many people have been seriously injured due to laziness and cheapness. Bad gas is more common than people realize. I hear a lot of ow divers say they get headaches after dives. It'd be interesting to see how many of those cases were due to a little CO.

It's not a huge risk but it's a risk.

 

[drrich2]

We face risks everyday, and in the interest of practicality and quality of life, choose to accept/overlook some of them as we go about living. Whether it's about deciding how much life or disability insurance to buy (or not to), what level of health insurance to buy, how far from 'civilization' (nearby 1st world health care facilities and maybe a chamber) we're willing to roam for diving, whether to get vaccinated against yellow fever or take prophylactics against malaria or whether to eat the local food...

At some point, a risk rises to the level, and mitigation strategies become practical and cheap enough, that yes, it's 'lazy or cheap' not to mitigate it.

The question is whether mainstream recreational divers doing mainstream dives (usually not over 111 feet), need to routinely analyze air tanks the chance somebody screwed up at the fill station in a way that'll seriously hurt them.

Is the risk known to rise to that level, or are people just guessing and choosing whichever response they like?

Richard.

 

[ReefHound]

The question is whether mainstream recreational divers doing mainstream dives (usually not over 111 feet), need to routinely analyze air tanks the chance somebody screwed up at the fill station in a way that'll seriously hurt them.

The same could be said for nitrox divers analyzing nitrox tanks. In the case I gave, we bank 32% and whether it comes out a lean 31% or a rich 33% it isn't going to vary much and the odds of it making "much" of a difference in risk is minimal. The deco obligation for exceeding ndl by a few minutes is going to be wiped out with your typical safety stop.

And we can use terms like "usually" to describe the dives but many of the dives in FG have the potential to greatly exceed 111'. We usually run a reel at the first site in FG and Stetson to the wall where it drops quickly to 150' and looks deceptively close. The platform dive has a bottom of 400'.

I'm not saying you're wrong in that I agree the risk is low, I'm just saying the risk is low either way and noting the stark contrast between how we view not analyzing your nitrox tank as playing russian roulette while not even considering the risk of not analyzing your air tank.

 

[Steve_C]

Two conversations going on. One about analyzing air. The other for analyzing for CO.

 

[TMHeimer]

On the other hand, EAN 32 seems to be far & away the most common nitrox mix, you mentioned that on that live-aboard you banked 32%, and with a MOD around 111 feet, it should in theory only become a concern if the divers get below that MOD. How often do rec. divers drop below 111 feet for any substantial period on most boat trips? What are the odds of a bad outcome in those cases where it happens?

Basically, I'm coming at the issue like this. If all across the U.S. we arbitrarily knocked 5 mph off the speed limit most everywhere, we might save some lives. But at some point, we look at the costs involved (not just money, but time, frustration, user preference), and decide hey, we are just plain not going to do that.

Point: In theory, it's a potential risk. In real world practice, does it rise to the level of being worth the cost/bother to mess with for most people most of the time?

If an op. were partial pressure blending nitrox and getting variable fill %'s, that could be a different situation. I'm assuming banked 32 from that example.

Richard.

Sorry to get off track, but have to point out the US Govt. said "55 saves lives" for a mandatory 12 years ('74-'86 and to '96 in many Eastern states). Remember the "double nickel" and Smokey Bear good buddy? Guess 65-70 is fine the last 20-30 years--who cares about saving lives? Hey, 50% of drivers exceed the speed limit by 5-10 mph anyway and the cops do nothing--other than speed along with them and not use directionals occasionally themselves.

 

[drrich2]

I heard somewhere that the nationwide 55 mph limit was set to control fuel usage for a period of time, and some noticed afterwards that mortality rates dropped. Wikipedia's National Maximum Speed Law page says: "It was drafted in response to oil price spikes and supply disruptions during the 1973 oil crisis.

While Federal officials hoped gasoline consumption would fall by 2.2%, actual savings were estimated at between 0.5% and 1%."

Turns out there are other factors that can play into reduced fatalities.

Where do you stop? If 55 mph is safer than 65 mph, might 45 mph not be safer than 55? That's my point; there's some often poorly-reasoned line people draw where one side's too dangerous, the other isn't. I'm curious how people draw that line where testing CO levels in scuba tanks is concerned.

It's a tangent outside the intended scope of this thread, & I doubt there are hard & fast answers to be had anyway, so probably better to accept various viewpoints have been expressed and let it go (or make a separate thread).

Richard.

 

[BRT]

I heard somewhere that the nationwide 55 mph limit was set to control fuel usage for a period of time, and some noticed afterwards that mortality rates dropped. Wikipedia's National Maximum Speed Law page says: "It was drafted in response to oil price spikes and supply disruptions during the 1973 oil crisis.

While Federal officials hoped gasoline consumption would fall by 2.2%, actual savings were estimated at between 0.5% and 1%."

Turns out there are other factors that can play into reduced fatalities.

Where do you stop? If 55 mph is safer than 65 mph, might 45 mph not be safer than 55? That's my point; there's some often poorly-reasoned line people draw where one side's too dangerous, other other isn't. I'm curious how people draw that line where testing CO levels in scuba tanks is concerned.

It's a tangent outside the intended scope of this thread, & I doubt there are hard & fast answers to be had anyway, so probably better to accept various viewpoints have been expressed and let it go (or make a separate thread).

Richard.

If we were serious about vehicle safety a 25 mph speed limit, 4 point harnesses and helmets would cure the problem. With scuba tanks everybody checking every tank for everything would reduce the death rate a tiny amount. That being said I still analyze for O2 content.

 

[The Chairman]

It was drafted in response to oil price spikes and supply disruptions during the 1973 oil crisis.

I remember that well. Whew! Heady times. I worked at a gas station at the corner of Lake Barton Drive (now Semoran) and Lake Underhill Rd. We mostly repaired vehicles, but when gas prices spiked, it was nigh to impossible to get into our shop. The owner thought it was really stoopid and stopped selling gas altogether. The gas was for only staff and we had to be careful how we pumped it or the lot would fill up. That was at the beginning of the electronic revolution in cars and we started seeing a lot more electronic ignition and even installed a lot of after market units. ANYTHING to improve gas mileage. Additives were all the rage too and we started moving away from rebuilding parts like brake shoes and fuel pumps to buying them ready to bolt on. Cars started downsizing, McPhereson Strut suspensions and disc brakes started to really become popular. Safety was being built in by necessity to increase MPGs. In addition, the earliest smog appliances, the lowly PCV valve was having an impact on the amount of oil on the road. The drip tubes of yesteryear were slowly being replaced by the PCV valve and the danger of black ice was reduced dramatically. Inadvertently, safety was improved. Yeah, it was a fun time to be a mechanic. Not as radical as 81 when the first computer modules hit cars, but fun nonetheless.