A barrier pipe is a type of water pipe with a barrier to prevent undesired contaminants from entering the pipe.
Water supply[edit]
When running water supply pipes through contaminated ground standard MDPE piping is unsuitable because it doesn't block entry of contaminants such as hydrocarbons. Barrier piping typically has an aluminium layer between two plastic layers but solid cast iron and other options exist. It's normally required for brownfield land construction.
Heating systems[edit]
In hydronic, water-carrying, heating systems a plastic pipe is manufactured with a barrier that prevents oxygen from penetrating the material and entering the water system, reducing the risk of corrosion. The 'barrier' is usually a resin material bonded between the outer and inner layer of the pipe itself. The pipe being either a cross linked polyethylene or polybutylene. This can be cheaper than the traditional copper piping.
Well, that’s interesting to know that Psilotum nudum are known as whisk ferns. Psilotum nudum is the commoner species of the two. While the P. flaccidum is a rare species and is found in the tropical islands. Both the species are usually epiphytic in habit and grow upon tree ferns. These species may also be terrestrial and grow in humus or in the crevices of the rocks.
View the detailed Guide of Psilotum nudum: Detailed Study Of Psilotum Nudum (Whisk Fern), Classification, Anatomy, Reproduction