🔍 Key Concepts

• Tank vent systems on tank vessels and cargo tanks • How flammable vapors behave at the tank vent outlet • Purpose of flame screens / flame arresters versus strainers or filters

💭 Think About

• Think about what hazard at the vent opening would be the most dangerous for a tank containing flammable cargo or fuel vapors. • Ask yourself: is the mesh size and corrosion resistance more important for blocking animals and trash, or for stopping something related to ignition and combustion? • Consider which of the options is normally handled by other shipboard arrangements (e.g., rodent guards, gooseneck bends, weather shields) rather than a fine metal mesh.

✅ Before You Answer

• Identify which choice directly addresses fire and explosion risk at the tank vent. • Eliminate any options that describe problems normally handled by covers, bends, or separate strainers, not by a fine corrosion‑resistant wire mesh right at the vent outlet. • Confirm which option matches the typical function of a flame screen/flame arrester on a tank vent.