1305.9.12 Pipe size; direct feed without fuel storage above the lowest floor.
MC § 1305.9.12
In systems with appliances above the lowest floor, where such appliances are designed to operate utilizing fuel pumped as needed from the lowest floor on demand sequenced with the equipment operation, piping diameters shall not exceed 4 inches (101.6 mm). Piping shall not be used for fuel storage purposes. Exceptions: 1. Piping diameters may exceed 4 inches (101.6 mm) where an applicant demonstrates, by calculations in the construction documents, that a greater diameter is necessary to ensure the proper flow for the functioning of the system.
2.Piping diameters within rooms containing fuel-burning equipment may exceed the calculated design flow pipe size to provide limited storage to prime equipment, provided such storage is counted toward the maximum permitted oil storage per story, as provided for in Section 1305.11.1.3.
