Plumbing Africa August 2017 | Page 49

FEATURES 47 State of odour capture By Tristan Wiggill Waste water traps, though unsung and rarely spoken of, are critical to health and safety, and form an integral part of modern sanitation systems. Waste water traps are designed to retain a small body of waste water from the system to which they are attached. By forming this liquid barrier, unpleasant odours and bacteria are stopped from travelling back down/up the trap and into one’s home or building. Rubber and PVC waste water traps are mostly used in inland applications, while polypropylene is preferred in the coastal areas in South Africa. Brass, meanwhile, is typically used for applications where chemicals are used, such as in laboratories. “Stainless steel traps are strong, corrosion resistant, and generally lower in maintenance than any other Continued on page 48 >> Similarly, foul-smelling gases and harmful pathogens from larger municipal sewers are prevented from entering household drainage systems with intercepting traps. Well-designed and well-constructed interceptors can quickly remove foul matter of residential or municipal sewers. Waste water traps are manufactured in rubber, PVC (white and black), polypropylene, brass, and stainless steel. They are classified as either P-Traps, Q-Traps, or S-Traps, depending on the shapes they take. Modern plastic waste plumbing (apart from WC’s), normally use either 32mm (for hand basins) or 40mm (for sinks, baths, showers, dishwashers, washing machines) pipe and fittings (including traps). www.plumbingafrica.co.za August 2017 Volume 23 I Number 6