LISTSERV mailing list manager LISTSERV 16.5

Help for SCUBA-L Archives


SCUBA-L Archives

SCUBA-L Archives


SCUBA-L@LISTSERV.BROWN.EDU


View:

Message:

[

First

|

Previous

|

Next

|

Last

]

By Topic:

[

First

|

Previous

|

Next

|

Last

]

By Author:

[

First

|

Previous

|

Next

|

Last

]

Font:

Monospaced Font

LISTSERV Archives

LISTSERV Archives

SCUBA-L Home

SCUBA-L Home

SCUBA-L  September 1999, Week 4

SCUBA-L September 1999, Week 4

Subject:

Re: TEST YOUR KNOWLEDGE

From:

Christian Gerzner <[log in to unmask]>

Reply-To:

Scuba diving discussion list <[log in to unmask]>

Date:

Tue, 21 Sep 1999 16:14:54 +1000

Content-Type:

text/plain

Parts/Attachments:

Parts/Attachments

text/plain (74 lines)

Bjorn Vang Jensen wrote:
(snip)
 
> No. What I HAVE heard is that the main concern is that oxygen degrades
> o-rings much faster than air. Comments ?
 
And Strike then wrote:
 
> In both instances the first-stage had nitrile 'o' rings fitted rather than
> viton 'o'rings, (nitrile 'o' rings often have very slight traces of oil
> present.), and when the cylinders were cracked open, (apparently quickly!
> Not - as you've already said - slowly), the 'o' rings ignited and burned
> out!
>
> Another problem with nitrile 'o'rings is that high partial pressures of O2
> can cause brittling!
 
As I understand it O2 cleaned regulators mostly have the soft components
made from viton or nitrile (I stand to be corrected).
 
I offer what follows without comment other than to say that I thought it
good enough to keep it and that I consider it a thought-provoking post:
 
> >Could be urban myth time but someone from one of the manufacturers told me
> >that viton decays in O2 faster than rubber decays in air.
>
> I don't know about the decay rate but it is a fact that when viton
> burns it produces an extremely poisonous gas. There is a lot of
> controversy as to whether viton or nitrile is suitable for O2 service -
> see the archives. I ordered some viton O-rings from a cylinder valve
> manufacturer (Sub-Aqua Products) and they said that they did not use
> viton for O2 compatible valves since nitrile were perfectly good - this
> ties in with the "official" specifications for nitrile too.
>
> For cylinders I used to think that O2 clean was good enough and that O2
> compatible seats/ debris tubes were unnecessary but have changed my
> mind. After this change of mind, this was reinforced when we recently
> had an incident where one of our members was just about to fill an
> O2-based cylinder with air to get his final mix when (it appears) the
> debris tube spontaneously combusted, wrecking the cylinder valve seat
> and filling whip too. It was fortunate that nobody was hurt.
>
> >Personally, I
> >just ignore all the O2 service hoo-haa and use my regs the way they came
> >(all of them carried warnings against use in 40%+ O2 environments).
>
> Industry standards say that anything for use in above 25% O2 should be
> in O2 service - makes you think eh?
>
> >
> >They aren't going to burst into flames, if an o-ring or seat fails then
> >you deal with it underwater as you would any other problem. It's not
> >the end of theworld.
>
> Have a look in the book "Oxygen First Aid for Divers" for some pictures
> of burnt regulators that did burst into flames on exposure to oxygen.
> I'm sure a troll around on the net would also turn up some interesting
> info. The arguments are basically to do with cost - do I accept a
> small but finite risk that my regs will burn or do I spend a few pounds
> to get them into O2 service and have a smaller but still finite risk
> that they will burn? I suppose with regulators you are the person
> making the decision and you are the one using them so pays your money
> and takes your choice (an informed one hopefully). Cylinders are a
> different matter - don't skimp the GBP 3-4 required to get the
> components O2 compatible - it just aint worth it and it isn't your risk
> to take.
 
For those who may care to take this further, the Archives referred to
can be found at <http://www.drogon.net/scuba/archive/>
 
Cheers,
 
Christian

Top of Message | Previous Page | Permalink

Advanced Options


Options

Log In

Log In

Get Password

Get Password


Search Archives

Search Archives


Subscribe or Unsubscribe

Subscribe or Unsubscribe


Archives

September 2016, Week 2
June 2016, Week 1
April 2016, Week 1
March 2015, Week 3
March 2015, Week 2
February 2015, Week 1
August 2014, Week 1
July 2014, Week 5
July 2014, Week 4
July 2014, Week 2
February 2014, Week 4
January 2014, Week 3
June 2013, Week 4
June 2013, Week 1
May 2013, Week 3
May 2013, Week 1
April 2013, Week 3
April 2013, Week 2
March 2013, Week 1
February 2013, Week 2
April 2012, Week 4
April 2012, Week 2
April 2012, Week 1
March 2012, Week 4
February 2012, Week 4
February 2012, Week 1
January 2012, Week 3
December 2011, Week 3
December 2011, Week 2
November 2011, Week 5
November 2011, Week 4
November 2011, Week 3
November 2011, Week 1
October 2011, Week 4
October 2011, Week 3
September 2011, Week 3
September 2011, Week 1
August 2011, Week 3
August 2011, Week 2
August 2011, Week 1
July 2011, Week 2
July 2011, Week 1
June 2011, Week 4
June 2011, Week 3
June 2011, Week 2
May 2011, Week 5
May 2011, Week 4
April 2011, Week 4
April 2011, Week 3
April 2011, Week 2
April 2011, Week 1
March 2011, Week 5
March 2011, Week 3
February 2011, Week 4
February 2011, Week 3
February 2011, Week 2
January 2011, Week 4
January 2011, Week 3
January 2011, Week 1
December 2010, Week 2
November 2010, Week 5
November 2010, Week 4
November 2010, Week 3
November 2010, Week 2
October 2010, Week 3
October 2010, Week 2
October 2010, Week 1
September 2010, Week 4
September 2010, Week 3
September 2010, Week 2
September 2010, Week 1
August 2010, Week 5
August 2010, Week 4
August 2010, Week 3
July 2010, Week 4
July 2010, Week 2
June 2010, Week 4
June 2010, Week 3
June 2010, Week 2
May 2010, Week 3
April 2010, Week 4
April 2010, Week 3
March 2010, Week 5
March 2010, Week 4
March 2010, Week 3
March 2010, Week 2
March 2010, Week 1
February 2010, Week 3
December 2009, Week 4
December 2009, Week 1
November 2009, Week 2
November 2009, Week 1
October 2009, Week 4
October 2009, Week 3
September 2009, Week 3
September 2009, Week 2
August 2009, Week 4
August 2009, Week 3
August 2009, Week 2
July 2009, Week 4
July 2009, Week 3
July 2009, Week 1
June 2009, Week 4
June 2009, Week 3
May 2009, Week 3
March 2009, Week 4
March 2009, Week 1
February 2009, Week 2
January 2009, Week 4
December 2008, Week 4
December 2008, Week 3
December 2008, Week 2
December 2008, Week 1
November 2008, Week 4
October 2008, Week 3
October 2008, Week 1
September 2008, Week 5
August 2008, Week 4
August 2008, Week 3
August 2008, Week 2
July 2008, Week 4
July 2008, Week 3
July 2008, Week 1
June 2008, Week 4
June 2008, Week 2
June 2008, Week 1
May 2008, Week 4
May 2008, Week 2
April 2008, Week 4
April 2008, Week 3
April 2008, Week 1
March 2008, Week 3
March 2008, Week 1
February 2008, Week 4
February 2008, Week 2
January 2008, Week 3
December 2007, Week 2
November 2007, Week 3
November 2007, Week 2
November 2007, Week 1
October 2007, Week 1
September 2007, Week 4
September 2007, Week 3
July 2007, Week 4
July 2007, Week 3
July 2007, Week 2
June 2007, Week 4
June 2007, Week 3
June 2007, Week 2
June 2007, Week 1
May 2007, Week 5
November 2006, Week 2
June 2006, Week 2
June 2006, Week 1
May 2006, Week 4
May 2006, Week 3
May 2006, Week 2
May 2006, Week 1
April 2006, Week 4
April 2006, Week 3
April 2006, Week 1
March 2006, Week 3
March 2006, Week 2
January 2006, Week 1
December 2005, Week 3
October 2005, Week 3
October 2005, Week 1
September 2005, Week 2
September 2005, Week 1
August 2005, Week 3
August 2005, Week 2
August 2005, Week 1
July 2005, Week 3
July 2005, Week 2
July 2005, Week 1
June 2005, Week 5
June 2005, Week 4
May 2005, Week 4
May 2005, Week 3
May 2005, Week 2
April 2005, Week 2
April 2005, Week 1
March 2005, Week 4
February 2005, Week 3
February 2005, Week 2
February 2005, Week 1
January 2005, Week 3
January 2005, Week 2
December 2004, Week 4
December 2004, Week 3
December 2004, Week 2
November 2004, Week 5
October 2004, Week 4
October 2004, Week 3
October 2004, Week 2
October 2004, Week 1
September 2004, Week 4
September 2004, Week 3
September 2004, Week 2
September 2004, Week 1
August 2004, Week 4
August 2004, Week 2
August 2004, Week 1
July 2004, Week 4
July 2004, Week 3
July 2004, Week 2
July 2004, Week 1
June 2004, Week 4
June 2004, Week 1
May 2004, Week 4
May 2004, Week 3
May 2004, Week 2
May 2004, Week 1
April 2004, Week 3
April 2004, Week 1
March 2004, Week 4
March 2004, Week 3
March 2004, Week 1
February 2004, Week 4
February 2004, Week 3
February 2004, Week 2
February 2004, Week 1
January 2004, Week 5
January 2004, Week 4
January 2004, Week 3
January 2004, Week 2
January 2004, Week 1
December 2003, Week 4
December 2003, Week 3
December 2003, Week 1
November 2003, Week 3
November 2003, Week 1
October 2003, Week 5
October 2003, Week 4
October 2003, Week 3
October 2003, Week 2
October 2003, Week 1
September 2003, Week 3
September 2003, Week 1
August 2003, Week 4
August 2003, Week 3
August 2003, Week 2
August 2003, Week 1
July 2003, Week 5
July 2003, Week 4
July 2003, Week 3
July 2003, Week 2
July 2003, Week 1
June 2003, Week 4
June 2003, Week 3
June 2003, Week 2
June 2003, Week 1
May 2003, Week 3
May 2003, Week 1
April 2003, Week 4
April 2003, Week 3
April 2003, Week 2
April 2003, Week 1
March 2003, Week 3
March 2003, Week 2
March 2003, Week 1
February 2003, Week 4
February 2003, Week 3
February 2003, Week 1
January 2003, Week 5
January 2003, Week 4
January 2003, Week 3
January 2003, Week 2
January 2003, Week 1
December 2002, Week 3
December 2002, Week 2
December 2002, Week 1
November 2002, Week 4
November 2002, Week 3
November 2002, Week 1
October 2002, Week 5
October 2002, Week 4
October 2002, Week 3
October 2002, Week 2
October 2002, Week 1
September 2002, Week 4
September 2002, Week 3
September 2002, Week 2
September 2002, Week 1
August 2002, Week 4
August 2002, Week 3
August 2002, Week 2
August 2002, Week 1
July 2002, Week 5
July 2002, Week 4
July 2002, Week 3
July 2002, Week 2
July 2002, Week 1
June 2002, Week 4
June 2002, Week 3
June 2002, Week 2
June 2002, Week 1
May 2002, Week 5
May 2002, Week 4
May 2002, Week 3
May 2002, Week 2
May 2002, Week 1
April 2002, Week 3
April 2002, Week 2
April 2002, Week 1
March 2002, Week 3
March 2002, Week 1
February 2002, Week 4
February 2002, Week 3
February 2002, Week 2
February 2002, Week 1
January 2002, Week 4
January 2002, Week 3
January 2002, Week 2
January 2002, Week 1
December 2001, Week 5
December 2001, Week 4
December 2001, Week 3
December 2001, Week 2
December 2001, Week 1
November 2001, Week 4
November 2001, Week 3
November 2001, Week 2
November 2001, Week 1
October 2001, Week 5
October 2001, Week 4
October 2001, Week 3
October 2001, Week 2
October 2001, Week 1
September 2001, Week 4
September 2001, Week 3
September 2001, Week 2
September 2001, Week 1
August 2001, Week 5
August 2001, Week 4
August 2001, Week 3
August 2001, Week 2
August 2001, Week 1
July 2001, Week 5
July 2001, Week 4
July 2001, Week 3
July 2001, Week 2
July 2001, Week 1
June 2001, Week 5
June 2001, Week 4
June 2001, Week 3
June 2001, Week 2
June 2001, Week 1
May 2001, Week 5
May 2001, Week 4
May 2001, Week 3
May 2001, Week 2
May 2001, Week 1
April 2001, Week 5
April 2001, Week 4
April 2001, Week 3
April 2001, Week 2
April 2001, Week 1
March 2001, Week 5
March 2001, Week 4
March 2001, Week 3
March 2001, Week 2
March 2001, Week 1
February 2001, Week 4
February 2001, Week 3
February 2001, Week 2
February 2001, Week 1
January 2001, Week 5
January 2001, Week 4
January 2001, Week 3
January 2001, Week 2
January 2001, Week 1
December 2000, Week 4
December 2000, Week 3
December 2000, Week 2
December 2000, Week 1
November 2000, Week 5
November 2000, Week 4
November 2000, Week 3
November 2000, Week 2
November 2000, Week 1
October 2000, Week 5
October 2000, Week 4
October 2000, Week 3
October 2000, Week 2
October 2000, Week 1
September 2000, Week 5
September 2000, Week 4
September 2000, Week 3
September 2000, Week 2
September 2000, Week 1
August 2000, Week 5
August 2000, Week 4
August 2000, Week 3
August 2000, Week 2
August 2000, Week 1
July 2000, Week 5
July 2000, Week 4
July 2000, Week 3
July 2000, Week 2
July 2000, Week 1
June 2000, Week 5
June 2000, Week 4
June 2000, Week 3
June 2000, Week 2
June 2000, Week 1
May 2000, Week 5
May 2000, Week 4
May 2000, Week 3
May 2000, Week 2
May 2000, Week 1
April 2000, Week 5
April 2000, Week 4
April 2000, Week 3
April 2000, Week 2
April 2000, Week 1
March 2000, Week 5
March 2000, Week 4
March 2000, Week 3
March 2000, Week 2
March 2000, Week 1
February 2000, Week 5
February 2000, Week 4
February 2000, Week 3
February 2000, Week 2
February 2000, Week 1
January 2000, Week 5
January 2000, Week 4
January 2000, Week 3
January 2000, Week 2
January 2000, Week 1
December 1999, Week 5
December 1999, Week 4
December 1999, Week 3
December 1999, Week 2
December 1999, Week 1
November 1999, Week 5
November 1999, Week 4
November 1999, Week 3
November 1999, Week 2
November 1999, Week 1
October 1999, Week 5
October 1999, Week 4
October 1999, Week 3
October 1999, Week 2
October 1999, Week 1
September 1999, Week 5
September 1999, Week 4
September 1999, Week 3
September 1999, Week 2
September 1999, Week 1
August 1999, Week 5
August 1999, Week 4
August 1999, Week 3
August 1999, Week 2
August 1999, Week 1
July 1999, Week 5
July 1999, Week 4
July 1999, Week 3
July 1999, Week 2
July 1999, Week 1
June 1999, Week 5
June 1999, Week 4
June 1999, Week 3
June 1999, Week 2
June 1999, Week 1
May 1999, Week 5
May 1999, Week 4
May 1999, Week 3
May 1999, Week 2
May 1999, Week 1
April 1999, Week 5
April 1999, Week 4
April 1999, Week 3
April 1999, Week 2
April 1999, Week 1

ATOM RSS1 RSS2



LISTSERV.BROWN.EDU

CataList Email List Search Powered by the LISTSERV Email List Manager