The Cast Iron Soil Pipe Institute (CISPI) was organized in 1949 by the leading American manufacturers of cast iron soil pipe and fittings. The Institute is dedicated to aiding and improving the plumbing industry. Through the preparation and distribution of technical reports, we seek to advance interest in the manufacture, use and distribution of cast iron soil pipe and fittings, and through a program of research and the cooperative effort of soil pipe manufacturers, we strive to improve the industry's products, achieve standardization of cast iron soil pipe and fittings, and provide a continuous program of product testing, evaluation and development. Since the founding of the Institute, member firms have standardized soil pipe and fittings, and have introduced a number of new products. Assurance that pipe and fittings meet the approved standards and tolerances of the Institute is provided either by C; or the CI NO-HUB trademarks which are the collective marks all member companies may place on their products.