In the semi-conductor manufacturing lies, some components or parts of the facility that are contaminated by chemical reactions during the manufacturing processes need to be cleansed periodically. Such cleansing is often performed by outside cleansing companies who take out the contaminated parts every day to its own cleansing facility; and, after cleansing, bring back the cleansed parts to the customer company repeatedly. In this paper, we &fie such a cleansing business as a new type of business; identify its unique characteristics; and discuss the productivity improvement methods by a case study.