This question came up in class?

"If the EMT has the supplementary protection what is the burial depth?

I suggested table 300.5 column 3 which is for nonmetallic raceways and other approved raceways.

what are your thoughts and comments on this questions?

I know from experience that EMT in direct contact with the eart doesn't last.

Thanks.

Agree all around. I am not sure EMT would actually get "approved" around here. It just turns to red dust in a year or two. Maybe they get away with it in a desert state.

I do not know if it would be approved here, but why would one use EMT for burial when PVC will last forever? As far as minium cover, whenever I have any doubt I always go with 24 inches of cover, sort of guaratees no one will dig it up while planting flowers.

column 3 would be correct as this is another approved raceway.The code allows it because their is no reason to prohibit it. This is a design choice and the code is not a design manual.

I would say Zero-inches if it's for an outdoor pool or hot tub installation. EMT doesn't appear to be allowed underground for pool feeders or branch circuits, although it looks like it can be used on or within buildings for pool related equipment and feeders with no problem.
Table 680.10 lists minimum cover depths for "other approved raceways" in these areas though, whatever those might be.

It was a hypothetical question that the student asked.

Thank you all for your replies.

Emt cannot be used underground or in ground slabs in Canada Eh!

I cant think of a reason why you would want to use it.