CJ corporation provides a water supply pipe cleaning service and has a technology that can effectively remove rusts and impurities accumulated inside a water supply pipe, which has installed in order to provide the tap water from a water treatment plant to the entrance of household's building, using the high-pressure nitrogen gas. The removal rate is more than 94% . This technology was developed for the first time in the world and succeeded in commercialization, and  that can clean whole water supply pipe in the city at once.