I am using 1 1/4 schedule 80 conduit to go across my driveway from my shop to garage and at the supply house they said to use the schedule 40 90's. They said nobody uses the schedule 80 90's plus they don't stock any. Where the 90's are is not going to be driven over. Is it acceptable?
Anywhere underground sch40 is fine. Exposed above ground and subject to damage you should use sch80.
Sometimes I feel like if I answer any more questions it is like someone trying to climb over a fence to jump off a bridge and me giving them a boost.
Answers based on the 2008 & 2011 NEC.