Yeah we had a couple of comments going back and forth with conflicting scenarios. The one I was responding too was stating exposed above ground conduit, where EMT is often better than PVC due to sun exposure. Ridged is of course even better from a durability perspective, but a real hassle to deal with.
Burying EMT in soil or concrete is generally a bad idea and quickly leads to some serious tears - sometimes in a year or two with the right soil or if the concrete is exposed to harsh conditions).
Most codes technically allow it though, sometimes with ‘supplementary corrosion protection’. NEC 358.10(b).
Some electricians use duct tape for the ‘protection’ which is terrible.
Proper pipe wrap is expensive and doing it on your own is a real hassle.
[https://www.electricallicenserenewal.com/Electrical-Continui...] random link with some pictures.
That is one of the areas where plastic really shines - I’ve had great luck with schedule 40 or 80 rated plastic conduit - always go up a step or two in size above
what you think you’ll need unless you hate future you. Schedule 80 for anything exposed to impact or exiting/entering the ground or a building.
And if you’re burying something like conduit, it’s almost always better to bury 2 or 3 instead of 1.
