On Feb 20, 8:07*pm, Gordon Henderson wrote:

All plastic cold water storage cisterns to the relevant British
Standard have been potable quality for 25 years or more. They should
have insulation, a snap-tight lid, a screened air vent, screened
overflow, etc. This is the byelaw 30 kit you may see mentioned.

You can't taste the plastic. The water will degrade if it geys warm
or if the lid isn't refitted after maintenance. The tank will have
installation instructions. It should be installed on a marine ply
base.