🔍 Key Concepts

• Thermal expansion of liquids in enclosed spaces like fuel tanks • Difference between flash point and storage/handling temperature of fuel oil • Why fuel tanks are never completely filled and always have ullage (expansion space)

💭 Think About

• If the fuel is loaded at a higher temperature than it will be when the ship is at sea, what happens to its volume later? • Which of the choices depends MOST directly on how much the fuel’s volume will change as its temperature changes? • Which items in the choices are mainly fixed fuel properties (don’t change with delivery temperature) versus operational decisions you make during bunkering?

✅ Before You Answer

• Identify which option is about volume change with temperature, not about combustion behavior • Remember that flash point is a laboratory property of the fuel and does not change just because the delivery is warmer or cooler • Think about why regulations require some empty space (ullage) in fuel tanks, especially when loading warm fuel that may cool and contract or later heat and expand