Coz Tanks & O-Rings

[Cert1967]

I also test every tank I dive for CO. CO can happen anywhere, even with a well maintained compressor system. To steal a line from @DandyDon "You can test the tanks you dive, or dive on hope. Testing is safer.”

And yes, 95% of the tanks are filled by the same station - it's a high volume operation that runs 18 hours a day.

CO detection? See up-thread ....

@Christi - how does your company check the cylinder’s supplied to your customers for CO?

 

[noj3333]

@Christi - how does your company check the cylinder’s supplied to your customers for CO?[/QUOTE]

Likely the same way all operators check... they don't (and im not faulting them).

Have you ever seen an operator check tanks for CO (outside of sending samples out to a lab for general quality control)? In my limited experience I have not.

 

[MMM]

When the OP asked about O-rings, how is it that some are now talking about CO? Two different issues. Perhaps start a new thread if you want to yak about the latter.

 

[gopbroek]

Back to O-rings, the OP brought up the color of the O-ring indicating the material it was made from. Most off the shelf O-rings have standard colors but you can order them in multiple different colors. As an example if you wished to stock Buna N -013's in white and -014's in red so that they are easy to distinguish, Global Oring out of Houston will be happy to make them and sell them to you. Bottom line the color is no guarantee of material composition.

 

[Griffo]

Maybe learning to dive in the pacific in third world countries has made me somewhat blasé, but I've discovered that some of you Americans get real worried about a yoke o-ring bubbling underwater. It's a very common occurrence over this side of the globe.

It was a real surprise to me in Belize on one dive where the wifes o-ring had a small leak and every single diver in the group came over to "tell us" about it. Usually by grabbing my fin and making urgent animated pointing motions to alert me of the fact that there was this little stream of bubbles.

One woman even decided to 'rescue' my wife and I had to tear her hands off of my wife underwater. All meant well, but they all seemed freaked.

 

[Hickdive]

I've seen a lot of those translucent white ''O'' rings at hot beach destinations...they're likely intended for the pressurized fluid transfer industry/beverage dispensers...food grade material...the local operators are probably buying anything they can get their hands on that will work...problem is...they don't work very well...or for very long...

Best...

W...

Translucent white o rings are standard replacement parts included in all Scubapro first stage maintenance kits. They're included for DIN regulators, however, if a dive operator is using yoke connection regulators, it wouldn't surprise me if they keep the translucent ones for tanks.

You cannot really make any assumptions as to material or shore rating or original manufactured purpose for any o ring just by the colour.

 

[W W Meixner]

Translucent white o rings are standard replacement parts included in all Scubapro first stage maintenance kits. They're included for DIN regulators, however, if a dive operator is using yoke connection regulators, it wouldn't surprise me if they keep the translucent ones for tanks.

You cannot really make any assumptions as to material or shore rating or original manufactured purpose for any o ring just by the colour.

HD...

True enough...for me...at hot beach destinations...I check everything the shop supplies like it was my own...especially valve ''O'' rings...if they appear to be worn/cracked/overly compressed...I remove them...clean the face of the valve with a Q-Tip...and replace them with one of my Viton ''O'' rings...

Christi's operation is not the norm...she's the exception...and operators like her are few and far between...

I've dove three quarters of the way around the world and back...and for every fully prepared/professional operator...there are ten that are so bare bones...if your not fully prepared for things like ''bad'' valve ''O'' rings...your going to be in trouble before you ever get started...

And...as far as letting a dive boat crew member ''tinker'' with any of ''my gear''...never happen...not to take anything away from good help...just my OCD...

You need to do your own prior planning...be familiar with everything you have...do all your pre-checks/servicing prior to gearing up on the boat...and have with you what you may need as far as spares/save your dive bits and pieces...there's no substitute for being properly prepared...

A thirty year old/fully functional Conshelf first stage...will do you more good than will a brand new $2000. titanium DIN first stage with a missing ''O'' ring that can't be immediately replaced...

You can store a lot of ''self help'' components in a spare mask box...tools included...

Where are all you former Boy Scouts...Be Prepared...

Best...

Warren

 

[GameChanger]

Why is that? You don't turn your tank on before hitting the water? If it's a bad o-ring, it will be hissing and you will hear it. If you don't hear it on the boat and it starts under water ow do you expect the dive crew to know? If you are concerned about your o-ring, who is ultimately responsible for your dive and checking equipment before hitting the water? If you are concerned with bad or rings, then do a visual check before having your gear set-up. Even doing a visual you may not catch a leak. They happen when they happen, this is why we carry extra o-rings.

Not sure where you are going with this Christi...Of course I turn my tank on before hitting the water. I do not necessarily agree that you will hear a a bad o-ring hissing, especially on a noisy boat. As a matter of fact, after I noticed the leaking o-ring on my dive, and also subsequent dives where other divers had leaking o-rings, I made a concerted effort to do a visual inspection of the o-rings and I also listened to my yoke connection as well as the connection on my son's tank. I watched the SPG and listened, literally placing my ear on the yoke. I heard nothing unusual and I did not note any drop in tank pressure. When my son hit the water I noticed that his o-ring was indeed leaking.

I also noted that even after notifying the Op's about the leaking o-rings after the dives, I did not see anyone take any action such as replacing the o-ring (like you stated) or tag the tank to replace it at a later time. I'm not saying it wasn't replaced, I just did not see anyone do anything. Perhaps this is why I noticed the frequency of o-rings leaking?

My original post asked the question if the dive Ops have QC controls in place. It seems like your Op does and I commend you for that.

 

[ReefHound]

Not sure where you are going with this Christi...Of course I turn my tank on before hitting the water. I do not necessarily agree that you will hear a a bad o-ring hissing, especially on a noisy boat.

I agree it can be hard to hear a very small leak with ambient noise but those are the very small soda-pop-fizz bubbles I'm not worried about.

I made a concerted effort to do a visual inspection of the o-rings and I also listened to my yoke connection as well as the connection on my son's tank. I watched the SPG and listened, literally placing my ear on the yoke. I heard nothing unusual and I did not note any drop in tank pressure. When my son hit the water I noticed that his o-ring was indeed leaking.

Eek! If the o-ring does extrude and pop, say goodbye to your eardrums.

I don't jump off the boat if I hear hissing but if it's so small you can't detect it on the surface then I'm not worried about it for recreational diving.

 

[blake7]

IMHO, by far the easiest way to check if there is any leak problem prior to splashing is to:

1. assemble all the gear
2. open the valve to pressurize the system fully
3. close the valve, note the SPG reading
4. keep an eye or stand near your gear to make sure no one purges or otherwise disturbs it
5. wait 2-5 min
6. check your SPG again

If you are within 100 psi of the reading in step 3, you are not having a leak that will create a problem. This also has the side benefit of checking if any of your equipment has developed a problem as well.