1. ROC Green Mark system the Department of Environmental Protection Department under the Green Mark to promote the Guidelines" and the "Green Mark Committee Guidelines" came into force, is in full compliance with ISO / CNS 14024 standards, the product inthe production process must not add any significantharm the environment substances. 2. Assume that there are four members in each family, each one will defecate once and urinate three times every day. The traditional water closet is a single stage flushing type. Water flushing amount is 12L each time. For two-stage flushing type, it consumes 6 liters of water for stool and 3. If each family installs a two-stage type water closet, saving water increases up to 40 million tons, equivalent to the storage amount of water of 4-5 Nanhua Reservoir.