Plastic pipes and plastic piping accessories may be better than metal pipes in most cases, particularly in plumbing, sewer systems, and gas and mining applications. There are several reasons for this. Plastic pipes are corrosion-resistant, chemically inert, lightweight, and very durable. These characteristics give plastic pipes a number of advantages over metal pipes.
For one, plastic pipes won't rust. They are chemically inert, so they can withstand most acids, bases, and salts. In contrast, chemical pipes are prone to corrosion from the outside and inside. Over time, corrosion inside metal pipes can lead to contamination, which can, in turn, lead to fixture damage and even safety issues. In severe cases, corrosion can cause pipes to burst.
Plastic pipes are also lightweight and easier to work with than metal pipes. Thus, one needs fewer personnel to install plastic pipes, which means lower installation costs. Additionally, plastic pipes cost less than metal pipes, with PVC being one of the most inexpensive piping materials around.