Thanks for the link Keith,yeah know it's not cheap stuff but would be perfect
for my job.
I would remove life lines leaving the support stanchion standing then bend and slot the plastic pipe over the stanchions.
I'm re corking the teak decks and other dry work on decks so after use pipe would be stored away for next winter crane out on the hard standing.
I think you can buy non tested pipe,either in gas,water or black waste it's just finding it.
cheers anyway...harry