The only membrane I have come across called HDPE is a Filter membrane which by its material nature (I can't remember the material now) is Hydrophobic i.e. will not let water pass through it...
I used them with a 5 micron pore size to protect a pressure transducer from water, or more accurately beer!!
I have no idea what tests you can do after joints(?) as I'm not sure what you mean.
John.
__________________
A little knowledge is a dangerous thing - Googling is far worse!
HDPE Membrane
Re: HDPE Membrane
