ProVent Systems offers its PVC-plastic, single-stack DWV system, which significantly reduces pipe and fittings and labor costs, while maximizing flow velocity. It increases the stack wastewater capacity and controls interior air pressures that could cause siphonage or blowouts of fixture traps. This system is non-corrosive, making it suitable for coastal areas, and it uses ProVent Whisper Quiet Shell Pipe, which test quieter than cast iron.