Gas pipe safe?

[Dee77]

I had a gas pipe which needed burying to accommodate changing kitchen layout plus patio door installation, as pipe was running across close to threshold. Gas plumber sunk pipe by channelling concrete floor which was then filled in with concrete/screed for later tiling.

Now having to dig out the fill at threshold due to damp issue I'm wondering if he has even sunk the pipe correctly? A builder came to look at other stuff and was a bit shocked at the insulation sleeving around the pipe. Other threads also suggest a minimum 200mm depth?

 

[mattylad]

Imagine someone coming in (after you have moved out), removing the tiles and fitting something to the floor with nails/screws ?
Psssst - bang.

Then decide if its deep enough or protected enough?