Risk of flooding premises from domestic sewage is almost always and exactly because of this rooms, especially the basement or the semi-basement, should be protect from possible flooding. You can do it by using non-return valves and anti-flood valves.
Anti-flood valve of the Hutterer & Lechner Company are installed both on plumbing fixtures and sewerage pipeline. If you install anti-flood valve on sewerage pipeline, it will be separation internal sewage from the external sewerage system.
The Hutterer & Lechner Company produces two types of anti-flood valves:
Mechanical anti-flood valves are made of ABS plastic and they have smooth output and socket input. Anti-flood valve have special flap made of stainless steel, some models are equipped with several flaps. Anti-flood valves are equipped with special hatches for their maintenance.
Anti-flood valves with electric drive are exploited in automatic mode, ie without any human intervention. All anti-flood valves with electric drive is double chamber - the first flap has an electric drive and the second flap is mechanical.
The Hutterer & Lechner Company also produces non-return valves, and they are installed on pipes which waste water do not contain fecal matter. Non-return valves are used for protection one or more sanitary devices.