Cindy,

If you went into a store here and asked for any size EMT, you'd be more likely to get a reply like "EMT guv? What's that then?" [Linked Image]

Just another of those American things which hardly anybody here knows about, along with Edsels and Gilligan's Island!

We don't have an EMT equivalent. There was some thinwall conduit used way back pre-war, but it hasn't been made for decades.

Heavy-gauge steel conduit is available in galvanized and black enamel finishes. The smallest sizes are 20 and 25mm, which replaced the old 3/4 and 1" types.

I've never heard of a 16mm gauge, though it might exist in some other country.

We do have 15 mm copper water pipe though. It replaced the 1/2-inch type in the 1970s, but is almost exactly the same size, because the 1/2-inch was measured as the bore and the 15mm is outside diameter.