🔍 Key Concepts

• 46 CFR Subchapter M requirements for towing vessel fuel tank vents • Purpose of a flame screen on a fuel tank vent • Why shut-off valves in fuel vent lines can be hazardous

💭 Think About

• Think about what a fuel tank vent is supposed to do during normal operation and during a fire. Would any of these options interfere with that purpose? • Which of these provisions, if installed on a vent line, could trap pressure or vacuum inside the fuel tank? • Which features are commonly required on fuel vents for tank protection and ignition prevention, and which one sounds like it might violate that safety intent?

✅ Before You Answer

• Verify in 46 CFR what is specified about flame screens on fuel tank vents (size and material) • Check whether fuel tank vent lines are allowed to have shut-off valves installed in them • Confirm that fuel tank vents generally must lead from the highest point of the tank to a safe discharge point on a weather deck