[PSUBS-MAILIST] Re: filling SCUBA tanks with shop compressors (was Pressure air drive)

[David Buchner <buchner@wcta.net>]

How awful.

Wow. This is definitely one of those things that's valuable to have out 
in the open, due to the largish number of people who read this list who 
are of a hacker mentality and always want to find a cheap, crude, 
homemade way to do things. (me! ;-)) Am I understanding right -- that 
the high heat as the air is going through the compressor causes the 
combustion resulting in CO *then*, and that the suffocation (or 
poisoning, or whatever the correct term is) was caused *later*, when 
somebody breathed the stored CO out of that tank?

That's scary, and another one of those things I never, ever would have 
thought of on my own, just sitting around scheming and dreaming.

Herve wrote:
>> It is prohibited to refill breathing air tanks from industrial 
>> compressor,
>> or air shop compressors. Scuba HP compressors are designed to fill up
>> cylinders with high pressure with no moisture or contaminated gas.
>> When you compress air, temp goes up and oil or grease residuts, if 
>> any, but
>> present in industrial comp can burn and produce CO, which is odorless.
>> Moisture in tanks creates oxydations inside, even in a aluminium tank 
>> and
>> weakens the walls.
>> In 1981 during my first scuba dive in the NAVY, 2 experienced divers 
>> on
>> another task died because of that. It was a n old compressor, and 
>> somebody
>> reversed a set of filters, which produced CO due to the high 
>> temperature.
>> They both lost conscience and drawned and never forgot that. So a good
>> advise....  use dedicated compressors to refill tanks and other life 
>> support
>> air sytems, and leave shop air compressors for air tools.


David
buchner@wcta.net
Osage, MN, USA
http://customer.wcta.net/buchner