Just check the wall thickness, it is a different product entirely. If I am
correct, it is not just polyethylene but a different type or mix of plastic.
Finally, it is color coded to identify it as gas pipe. Connections are made
with special fittings and/or are plastic welded.

wrote in message
oups.com...
what is the difference between the yellow polythylene
pipe designed for gas, and garden variety black polythylene pipe? I am
not planning on using the black stuff, but just curious, as the gas
pipe seems more expensive.