Low cost sensor combats floods

Problem: . Plumbers have to be summoned, usually rubbing their hands at the prospect of being able to charge whatever they please in an emergency likely to result in ceilings coming down by the time they arrive. The problem is exacerbated in care homes and institutions, where forgetfulness adds to the risk, and even more in public facilities prone to the attention of vandals who take mindless pleasure in causing damage and disaster. Solution: James Barnham, a graduating student at London South Bank University has developed and tested a system which uses an exceptionally low cost sensor, and mechanics only to shut off water supplies in the event of a flood. His prototype sensor uses a soluble aspirin tablet which on dissolution, allows a spring loaded bowden cable system - the kind of device used to work bicycle brakes - to shut off the water supply. Encountered at the recently held "Style:Works" design show at the university, he said that in tests, the system triggered in 20 seconds. He also said that no false triggering due to damp absorbed from the atmosphere took place over a period of several months. The use of bowden cables rather than electrics ensures that the system is both safe and functional during flood events. Applications: Any system designed to react on detecting the presence of water. As well as domestic and care home bathrooms, the system is equally applicable to the process plant environment. Because of its lack of electrics, it is worth noting that it is also intrinsically safe. TS Email James Barnham South Bank University Design Show