Yes or No?

[NeilB]

However people confuse not dripping with oil with surgically clean standards. The classic idiocy is the "You've touched it so it has to be re-cleaned" line. What goes for a scalpel contaminated with bugs that can reproduce exponentially does not apply to simple chemicals.

That will explain what I saw on the video then.

An Ambient Pressure Diving man shows how to put a scrubber back together. He sticks his finger in the oxygen compatible grease and smears it on the O ring. Then installs the O ring in the scrubber.

I did wonder if his finger would contaminate the grease.....obviously not enough to worry about.

[vasco]

I'm thinking specifically with regard to Red Sea live aboards, I don't have a regular dive buddy and after many trips I think I have had my fair share of 'less than confidence inspiring' buddies.

Therefore thinking of taking my own bit of redundancy with me in the shape of a pony., which I don't belive are available on boats to hire.

You can hire a pony in Egypt, seen them on Tony Backhurst boats. I don't know this is true on all liveaboards though.

[jamesp]

JamesP “How many atmospheres do you reckon the pressure will drop by?”
3.246 – roughly.
As I said, assuming the hold isn’t pressurised. Also assuming you ascend to around 35,000 feet and with a standardised sea level temperature of 59F. When you put your bit of sticky tape on the tank valve at sea level you would be doing so at a pressure of roughly 29.92 in/Hg (say 14.69 psi). As you ascend to 35,000 feet the ambient pressure drops to around 7.04 in/Hg (say 3.46 psi). Therefore, (14.69 psi/3.46psi) – 1 ata = 3.246 ata
Even with a pressurised hold it could drop around 1.39 ata. In this case assuming you are flying at around the same height and using the standardised minimum recommended cabin pressure of 10.9 psi . Dropping now only 3.79 psi. In either case I still would not rate your sticky tape’s chances of providing a seal.
Normalising all references to atmosphere at an assumed sea level is, in my experience, a convention that is common only in diving and some of the more basic realms of engineering. Presumably to make the concept a little easier to grasp. You’ll forgive me if my terms of reference differ a little from yours. You are of course quite correct though, it seems that having done the calculations my original guess of “a couple of atmospheres” was far too conservative.
You need not worry about the possibility of diving on one of my dodgy blends. I reserve these purely for personal consumption. On the other hand you may be more concerned to hear that my former students could well be designing the cars that you drive, the bridges that you drive over, possibly the aircraft in which you fly and maybe even the chambers that you frequent. I wouldn’t let this play on your mind though, it will no doubt just worry you.

Roving Shark
“The same muck that was in there in the first place or the stuff that’s magically appeared”
Now this really isn’t my area of expertise. I’ll simply have to take your word for the fact that the air on commercial aircraft is so wonderfully pure. Is the food delicious too?
“Agency bashing” Excuse me? I believe I was supporting the stance that I hear is taken by that particular agency. How would that be bashing? And “Facts”, please.

It has been a blast but I think, on reflection, I’ll leave the Yorkshire Divers Community with its own peculiar take on the physical world. It really has been an education. Happy diving.

Was this guy really serious?

Back to the OP, I have friends who have hired pony cylinders out there(booked in advance) and taken cylinders out in hold luggage.
With the changes in weight limits on luggage and the immense variability in the application of the baggage rules at the airport, you would be better hiring through the tour operator.
For my money the airport transfer will carry more risk than any of the diving!

[MarkP]

Now I'm curious - Mr Wing Nut seemed to want to be helpful, though somewhat lacking a working knowledge of physics.

What did he do to justify the red stuff that appeared? I've read through his posts and can't see anything immediately obvious.

(Mind you, he did state that he does partial pressure fills...)

[Scuttler]

3.246 – roughly.
As I said, assuming the hold isn’t pressurised. Also assuming you ascend to around 35,000 feet and with a standardised sea level temperature of 59F. When you put your bit of sticky tape on the tank valve at sea level you would be doing so at a pressure of roughly 29.92 in/Hg (say 14.69 psi). As you ascend to 35,000 feet the ambient pressure drops to around 7.04 in/Hg (say 3.46 psi). Therefore, (14.69 psi/3.46psi) – 1 ata = 3.246 ata
Even with a pressurised hold it could drop around 1.39 ata. In this case assuming you are flying at around the same height and using the standardised minimum recommended cabin pressure of 10.9 psi . Dropping now only 3.79 psi. .

Funny as fuck!!! Somone has spent too much time reading and not enough time understanding!

[Scuttler]

Now I'm curious - Mr Wing Nut seemed to want to be helpful, though somewhat lacking a working knowledge of physics.

What did he do to justify the red stuff that appeared? I've read through his posts and can't see anything immediately obvious.

(Mind you, he did state that he does partial pressure fills...)

As he's new and not built up a rep he'd only need to get one red from someone with a high rep stat and it would max out his blobometer.

[nickb]

This stuff's priceless. I reckon we should all be greening wingnut for challenging the laws of physics and inventing the hardest vacuum in the known universe: minus 2.246 Bar indeed.

I'll green him, we need his sort around on Friday afternoons

[jamesp]

Now I'm curious - Mr Wing Nut seemed to want to be helpful, though somewhat lacking a working knowledge of physics.

What did he do to justify the red stuff that appeared? I've read through his posts and can't see anything immediately obvious.

(Mind you, he did state that he does partial pressure fills...)

I never blobed him!
It`s probably due to him leaving in a huff, though in that vacuum it should have boiled off fairly quickly.

[Rovingshark]

I never blobed him!
It`s probably due to him leaving in a huff.

I thought he left after about an hour & a huff.

RS

[Tilesey]

Calll me Dr Dumb, but in the very unlikely event that the hold weren't pressurised I'm struggling to work out just how the pressure would drop by any more than one atmosphere, even if said aircraft flew to the moon and beyond.

Besides, as any fule kno, to maintain O2 clean status you need to put green tape over the open valve.

Call me Dr Dummer, I have no idea either.