From the GMA Techline
Subject: Standard needed — I need the standard GM11. We produce geomembranes and we will do testing but I do not have the ageing standard. (Yohana, Colombia)
Reply: The GRI–GM11 Test Method has now been superseded by ASTM D7238 and ours has been discontinued. Please go directly to ASTM in this regard. The only difference is that GM11 called for 70°C incubation and D7238 calls for 75°C incubation. All of our research has been done at 70°C.