Low Noise Drainage System, Redefined: Silencio Product Catalogue Astral Silencio is a top-quality, sound-insulating, low-noise drainage and sewerage piping system suitable for commercial and residential wastewater drainage. It can endure hot and cold wastewater and fulfills all the requirements of non-pressurized wastewater piping as laid down in DIN EN 12056 and DIN 1986-100.