Section 658-109-12 - Inside Oil Supply Tanks1. No oil supply tanks may be installed on wood or other combustible surfaces.2. The installation of an unenclosed supply tank(s) located inside a building(s) without a finished cement floor, shall be supported by (4) four 4x8x16 inch reinforced concrete blocks or a reinforced concrete pad. The pad shall be at least three (3) inches thick, the width and length extending the full dimensions of the tank. The tank legs shall not exceed twelve (12) inches in height with floor flanges at the base of the steel legs. There must be a minimum of 4 inches of clearance under the tank from any surface. A. An inside oil supply tank shall be mounted on steel pipe legs not exceeding twelve (12) inches in height. The steel pipe legs or flanges must be in direct contact with a reinforced concrete pad or a reinforced concrete block under each leg. Click here to view Image
B. The top of all of the fuel oil tanks on a multiple tank installation shall be on the same horizontal plane.C. Oil shut-off valves shall be provided immediately adjacent to the burner supply connections at the bottom of the supply tanks.D. The manifold at the cross connections of the burner supply line, shall be of steel, wrought-iron pipe or copper tubing. (Standards for Steel and Wrought-Iron Pipe, ANSI B36.10). The manifold piping shall be as close to the shutoff valves as possible so that the distance between the tank and the last fitting shall not extend beyond (6) six inches from the face of the tanks and the final fitting (elbow or tee). See Figure 13(b).E. On multiple tank installations, it is the installer's responsibility to ensure that return line product will not cause spillage.F. When installing multiple fuel oil tanks with separate fill pipes and a common venting system, the requirement for increasing the vent pipe one pipe size larger than the largest individual vent pipe shall not be required.3. When installing two tanks that are cross connected according to Figure 7.7.1 of NFPA #31, 2006 edition, the gauge must be installed only in the vented tank and all burner supply piping from the tank outlet to the filter installed at the tank must be black iron pipe. The piping connected from the second tank may be either black iron pipe or copper tubing. If the filter is not located at the tank manifold, then copper tubing may be used to connect the black iron pipe manifold to the inlet of the filter.4. When removing, replacing, or taking a tank out of service for any period of time, the oil tank fill and vent piping shall be removed from the side of the building.02- 658 C.M.R. ch. 109, § 12