Brass gas line

I know copper is normally not approved for gas piping depending on sulfide content, but what about brass? Thanks in advance.

I spent a lot of time replacing brass flex fittings for Sears because they were dangerous due to the corrosive effect of gas on them.
I had them literally break off as I moved the stoves.

Check this out. Maybe it will help. http://www.engineeringtoolbox.com/approved-gas-pipes-d_1112.html