I am Jimook Moon, a manager of an industrial research team in the Korea Vinyl Environmental Council, KOVEC.

Recently, we arehave been facing a problem regarding the pipe installed in public buildings.
So, we would like to know if you, the US, have any restriction that basement pipes should be made of non-combustible materials or metal by any law or regulation.

The problem we are facing is described below.

A public corporation (LH) amended its specifications for public buildings.
(original) The basement pipes should be made of cast iron.
→ (amendment) The basement pipes should be made of PVC.
Cast iron pipe manufacturesmanufacturers filed a civil complaint about the amendment. Their argument is that basement pipes should be made of non-combustible materials or metal, for the safety of residents.
But the LH argues that theythere have been filed so many complaints of backup or backwards flowingbackwards-flowing from residents of public buildings. And most of the problem was caused by the clogged cast-iron pipeline.

If you know any restriction in any country for the basement pipe for draindrains being made of non-combustible materials, please let us know.