46 CFR §128.440

1. (a)Except as provided by this section, each bilge system must comply with §§ 56.50-50 and 56.50-55 of this chapter.
2. (b)If the steering room, engine room, centerline passageway, forward machinery space, and compartment containing the dry-mud tanks are the only below-deck spaces that must be fitted with bilge suctions, the vessel may be equipped to the standards of §§ 56.50-50 and 56.50-57 of this chapter applicable to a dry-cargo vessel of less than 55 meters (180 feet) in length.