46 C.F.R. § 108.439
(c) If fuel can drain from a space to an adjacent space or if two spaces are not entirely separate, the requirements for both spaces must be used to determine the amount of CO2 to be provided and the CO2 system must be arranged to discharge into both spaces simultaneously.
| Over | Not over | Factor |
|---|---|---|
| 0 | 500 | 15 |
| 500 | 1,600 | 16 |
| 1,600 | 4,500 | 18 |
| 4,500 | 50,000 | 20 |
| 50,000 | 22 |