Code of Federal Regulations Title 46. Shipping § 46.108.469 Quantity of foam producing materials

(a) Except as provided in paragraph (b) of this section, each foam extinguishing system with outlets—

(b) If a foam system has outlets in more than one tank or space, the system need have only enough foam producing material to cover the largest space that the system covers or, if the liquid surface of a tank covered by the system is larger, the tank with the largest liquid surface.