Does PEX tubing in closet require protective sleeve

[Tangent]

The HVAC inspection was approved by town, but I learned there is yet another inspection since the first one was "rough."

If required, what would be the simplest conduit or other protection I could install vertically?

 

[Sylvan]

When we pass piping through a wall or slab, we place it in an iron pipe sleeve 2 commercial sizes larger to protect it.