Oxygen barrier pex

[warm in VT]

I have heard about the oxygen barrier pex and that it is critical. Is that only for pressurized systems? My system is open to the air at the boiler vent cap at the OWB. Is the use of 02 barrier critical for open systems as well as the closed? I just read a response to make sure the 02 barrier does not get scraped off the pex and mine has rubbed against the cement wall indoors, scuffing it a little before I found that it had rubbed due to the heating of the pex and expanding.
Thanks.

 

[deerefanatic]

In an open system like yours it doesn't matter. In a closed system, well, yes, it matters. Mine has scrapes and scratches in it from installation. We'll see down the road how bad my system rusts out.