Dangerous lies?

[acxc]

Seriously? Yikes. I guess it goes to show that Natural Selection really does operate too slowly sometimes.

I don't think it's as much an issue of Natural Selection working too slowly as it is the inability to learn the function of a BC in a weekend, but that's a whole new argument.

But yeah, this was overheard at the start of a night dive where I randomly tagged along with an advanced class since I did not have a buddy. I now use this story as an example for my "How to Know Its a Good Idea to Call Your Dive Before it Starts" lecture for my own classes...

 

[Dan]

This is true.



This is only true if you are reaching your NDL before you empty the tank. Not the case for most rec divers. Nitrox extends your NDL time. It does nothing re. your gas consumption. This is a common misconception. You will breathe a tank down at the same rate with Nitrox as with air.

Yes, I heard this often about you can dive longer with Nitrox & being misunderstood of the word "longer" as less air consumption instead of more NDL bottom time. If you are an air hogger, using Nitrox will be a waste of gas. You will always be running out of gas before you are running out of NDL bottom time.

 

[cipherbreak]

If you get scared just press the red button on your BC and you'll go right to the surface.

Depending on the inflator, that might be true. Pressing the red button will, in fact, take you right to the surface. Not a good idea though.

Yes, I heard this often about you can dive longer with Nitrox & being misunderstood of the word "longer" as less air consumption instead of more NDL bottom time. If you are an air hogger, using Nitrox will be a waste of gas. You will always be running out of gas before you are running out of NDL bottom time.

Not entirely a waste. There's a safety advantage if you are not diving to the NDL.

 

[kelemvor]

Here's one.

I've often heard that you can't have both added safety and increased dive time with nitrox.

 

[nolatom]

I don't recall hearing or being taught any lies about scuba itself--maybe I've heard "misstatements" about current, vis, water temp, what have you, but not about the basic safety, gas usage, navigation, situational awareness stuff.

Lies get us killed.

Sorry if this is a boring answer. Good instruction has made me boring in this regard.

 

[dlofting]

Not a safety issue, but the people who still turn the tank valve back a quarter turn. I have to do this to my bathroom shower faucet, but then it is brass.

 

[Wookie]

Not a safety issue, but the people who still turn the tank valve back a quarter turn. I have to do this to my bathroom shower faucet, but then it is brass.

You really open a shower valve all the way and back 1/4 turn? I do that to my scuba valves, but never in the shower. I'd scald or freeze.

 

[Adam Grose]

How about "If you use (insert whatever equipment it is here), you WILL die".

 

[KeithG]

first dive is your deepest (sounds like a cat stevens song?)...

this was from a DM that upon discovering that we only went to 50 feet on our first dive recommended we immediately do a quick bounce dive to 70 feet so that we would be safe to do the afternoon dive to 60 feet.

 

[stuartv]

This is only true if you are reaching your NDL before you empty the tank.

Uhhh, I think that's why he said "Depending on your gas consumption"....