675 IAC 14-4.4-120 Section M1601.1.2; underground duct systems

Sec. 120. Change the text of SECTION M1601.1.2 to read as follows: Underground duct systems shall be constructed of approved concrete, clay, metal, or plastic. The maximum design temperature for systems utilizing plastic duct and fittings shall be 150°F (66°C). Metal ducts shall be protected from corrosion in an approved manner or shall be completely encased in concrete not less than 2 inches (51 mm) thick. Nonmetallic ducts shall be installed in accordance with the manufacturer's instructions. Plastic pipe and fitting materials shall conform to cell classification 12454-B of ASTM D1248 or ASTM D1784 and external loading properties of ASTM D2412. Ducts shall slope to a drainage point that has access. Ducts shall be sealed according to the manufacturer's installation instructions or Section M1601.4 prior to encasing the ducts in concrete or direct burial. Metallic ducts that have an approved protective coating and nonmetallic ducts shall be installed in accordance with the manufacturer's instructions.