(1) When a carbon dioxide (CO2) smothering system is fitted in the cargo hold, cargo 'tween-decks, or other closed cargo compartments, or cargo-oil deep tanks, the quantity of carbon dioxide shall be sufficient to give a gas saturation of 30 percent of the gross volume of the largest cargo hold. The quantity in pounds of carbon dioxide required may be determined approximately by the following formula: View Image
where:
W = the weight of CO2 required, in pounds.
L = the length of the hold, in feet.
B = the mean breadth of the hold, in feet,
D = the depth from tank top or flat forming lower boundary to top of uppermost space in which freight may be carried, in feet.