Qual oil pipe

[DaveyHep]

The above are all good reasons to only use top-outlet tanks.
I run a single run of qualpipe underground then above ground inside 20mm metal conduit to a glanded box. Connection to copper is inside the box. Qualpipe is protected from UV and no underground joints. Of course the qualpipe above ground is not fireproof but on a top-outlet tank it's not an issue.

 

[ShaunCorbs]

The above are all good reasons to only use top-outlet tanks.
I run a single run of qualpipe underground then above ground inside 20mm metal conduit to a glanded box. Connection to copper is inside the box. Qualpipe is protected from UV and no underground joints. Of course the qualpipe above ground is not fireproof but on a top-outlet tank it's not an issue.

they said that wasn’t an option as I was going to run it in 6m of 20mm galv conduit

 

[DaveyHep]

Shaun - I would agree for a bottom-outlet tank. Conduit would provide no protection from the heat of a fire. It'll have to be copper down into the ground. Then swap to copper inside an inspection chamber.
What we need is a fire rated sleeve to go over the plastic pipe to allow it to be brought above ground. We use such things in industry but they would be prohibitively expensive for domestic use.