Code of Federal Regulations Title 46. Shipping § 46.179.240 Foam flotation material

(1) All foam must comply with NPFC MIL–P–21929C (incorporated by reference, see 46 CFR 175.600). The fire resistance test is not required.

(2) Foam may be installed only in void spaces that are free of ignition sources, unless the foam complies with the requirements of 33 CFR 183.114;

(3) Foam may be installed adjacent to fuel tanks only if the boundary between the tank and the space has double continuous fillet welds;

(4) The structure enclosing the foam must be strong enough to accommodate the buoyancy of the foam;

(5) Piping and cables must not pass through foamed spaces unless they are within piping and cable ways accessible from both ends;

(6) Blocked foam must:

(7) A water submergence test must be conducted on the foam for a period of at least 7 days to demonstrate to the satisfaction of the cognizant OCMI that the foam has adequate strength to withstand a hydrostatic head equivalent to that which would be imposed if the vessel were submerged to its bulkhead deck;

(8) The effective buoyancy of the foam must be determined at the end of the submergence test required by paragraph (b)(7) of this section. The effective buoyancy or 881 kilograms per cubic meter (55 pounds per cubic foot), whichever is less, must be used in determining the location of watertight bulkheads for subdivision required by § 179.212;  and

(9) The owner or operator must obtain sample foam specimens during installation of the foam and determine the density of the installed foam.