🔍 Key Concepts

• Cargo classifications for flammable vs. combustible liquids in 46 CFR Subchapter D • Venting requirements for tank barges carrying Grade D and E oils such as No. 6 fuel oil • Differences between individual tank vents and common vent headers

💭 Think About

• First, determine what cargo grade No. 6 fuel oil falls under and how that affects venting requirements. • Next, think about whether regulations require each tank to have its own vent or if they can share a common venting system. • Consider which vent type is specifically called out in the regulations for high-flash-point oils like No. 6 fuel oil.

✅ Before You Answer

• Verify how No. 6 fuel oil is classified (e.g., Grade D or E cargo) under 46 CFR. • Check which venting arrangement is explicitly required for combustible oils with relatively high flash points. • Confirm whether regulations emphasize pressure control, flame arresting, or common venting for this type of cargo.