Best Answer: the rate of diffusion is directly proportional to the concentration gradient. The greater the difference in concentration between two areas, the greater the rate of diffusion.
EPC-40: Electrical Plastic Conduit : Designed for normal duty application. EPC-80: Electrical Plastic Conduit : Designed for heavy duty application.
Schedule 80 Conduit & Elbows. 1  PVC Rigid Nonmetallic Conduit (Extra Heavy Wall EPC-80) 2  Listed for use in aboveground and belowground applications including areas subject to physical damage. 3  Rated for use with 90Â°C conductors. 4  Superior weathering characteristics. 5  Identified for use in areas subject to physical damage in accordance to 352.12(C)