propress G standars in North America

[rdkohn]

I have been searching the literature for standards/codes that will SPECIFICALLY authorize the use of propress G type systems in home gas installations in North America. Strangely enough it is very hard to point out a specific standard that states that it is approved and safe to use this system for gas use. Can anyone tell me which standards approve this and where I can look/purchase such standards? Also, it seems strange to me that I cannot simply find these standards in the propress web site!

Any help would be highly appreciated,

Ricardo Kohn.