Thanks
@Wookie
But the Eaton Synflex is not a rubber hose. That is a thermoplastic hose that has many industrial applications. At least according to the EATON web site.
Does anyone actually uses that hose as an LP Scuba hose?
I couldn’t find the AMRON hose in their web site, but that does look like a typical rubber hose.
I am not at all surprised to see that combination. The two types of rubber (Nitrile and Neoprene) can be mechanically similar even if other properties are somewhat different.
BTW, Nitrile and Buna-N are two names for the same type of rubber.
Hoses often (especially buna hoses used in oxygen rich environments) rot from the inside out. That's why the outer sheath have small holes, to let you know they are letting go.
Could you expand on what type of application this has been observed? Are we talking Scuba application, aviation oxygen, medical O2, or some other application were the hoses are exposed to O2 for long periods of time?
Let me explain why I ask.
If I was a dive master in the Caribbean diving 5 times a week (using Nitro 32 or 36), 2 dives a day for let's say 50 weeks a year. That is roughly 500 hours a year of exposing my hoses (assuming an average of 1 hour long dives). In a year that works out to a time exposure of about 5.7% of the year (8760 hours).
When the regulator is pressurized (and diving) the IP may go up to 13 Bar (189 psi) absolute with an O2 partial pressure of about 4.7 Bars. The other 94% of the time the O2 level will quickly return to 0.21 atm.
In my case, I average about 100 logged dives a year. I just don’t worry about the oxygen exposure on any of my hoses or the O-rings in my regulators. Not for some O2 exposure for about 1% of the year or less. But, that is just me. YMMV
I am OK with others replacing their hoses every 5 years. It may be good for the economy. It is just bad for the land fills.
I would be concern with the O-rings on tank valves with high O2, but I don’t have any of those (other than my emergency medical O2 kits).
Personally, I see the inside environment of my LP hoses to be much more benign to the outside. The outside is exposed to sun, oils, dust , dirt, salt water, abrasion, etc.
I have a collection of both double hose and single hose regulators from the 70's and earlier. I have no issue using the LP hoses on most of the single hose regulators. Many look new and they surely never saw high O2 exposure.
BTW, IMO from observation, the worst exposure most Scuba hoses will experience is actually very benign as compared to some hoses use in industry for many years without being replaced.
Thanks
