nicktheplumber
You can use PVC gas wrapping tape to protect copper tubing buried under concrete. PASCO is one manufacturer. The tape comes in rolls that are about the same size as duct tape rolls.
Follow the instructions for wrapping to make sure you cover the pipe well. Make damned sure there are no leaks before the slab is placed and do yourself a favor by making a diagram showing exactly where the pipe runs, should you ever need to brak up the slab to fix it…
NtP
