Re: Getting with the program

dive-instructors.com, the first place to look for a dive instructor

[ Follow Ups ] [ Post Followup ] [ California Scuba Diving BBS ] [ FAQ ]

Posted by Ken Kurtis on August 24, 2005 at 09:10:44:

In Reply to: Getting with the program posted by Elaine on August 23, 2005 at 22:49:59:

Elaine wrote: "It seems like they need to update their policy and proceedure."

Without meaning to sound too nasty about this . . . no . . . you need to understand this from a store's persepctive.

If the tanks are simply being VIPed, I fully agree that nitrox stickers on them shouldn't matter. In fact, the statndard for VIPs is for ALL stickers (inclduing old VIP stickers) to be removed before a VIP is started so you can check for external corrosion under the stickers. And since, durting the VIP process, the open tank is exposed to 1-atm air, it obviously can't contain any nitrox when the valve is off. VIP can be done, tank filled with air, returned to customer.

However . . .

Filling tanks used for nitrox with air is a whole 'nother matter. There are varying and copntradictory viewpoints on this. There are concerns from operators about nitrox blowback into your system that may cause problems down the road. There are concerns about putting air that may not be 100% hydrocarbon free into a cylinder that is then used in an EAN-capacity. This isn't as simple as "Just fill me tank."

A lot of stores (ours included) will simply not fill a tank with air if it's got a nitrox sticker on it. Sure, they may be no problems. But if there are problems down the road, why do we want to potentially inject ourselves into that liability chain?

As for those who will say, "We'll I'll just bring my unlabelled nitrox tranks to you and you'll never know the difference." Yeah, we probably won't. But the accepted industry standard, despite what others might contend, IS to have nitrox tanks labelled as such so your deception will help remove us from the liability chain.

One of the professionals we deal with at Compressed Air Specialties told me one time that he was inspecting cylinders at a shop where they switched back and forth between air and nitrox in the same tank(s). (Not sure of the mix %.) In about half the tanks, he found small, black spots along the tank walls. He asked the shop owners if they knew what the spots were. They said they didn't. He explained that the spots were residual from small, spontaneous oxygen combustion explosions that were ocurring in the tanks as a result of their dual air/nirtrox use. He told them that if they continued doing what they did, at some point here was a good chance they were going to have a tank explode. Needless to say, they changed their procedures.

This whole issue isn't as simple as some would have you believe. My advice to everyone would be to get ALL the facts and understand ALL the issues before you start advising people, let alone stores who deal with this every day, on what to do.

Ken Kurtis
NAUI Instr. #5936
Co-owner, Reef Seekers Dive Co.
Beverly Hills, CA

Follow Ups:

Optional Link URL:
Optional Link Title:
Optional Image URL:
Post Background Color: White     Black
Post Area Page Width: Normal   Full
You must type in the
scrambled text key to
the right.
This is required to
help prevent spam bots
from flooding this BBS.
Text Key: