🔍 Key Concepts

• Inerting and gassing-up operations on tankers and cargo tanks • The purpose of a dew point meter versus an oxygen meter • What condition inside the tank tells you that flammable vapors have been safely replaced

💭 Think About

• Ask yourself: during gassing up, what are you changing inside the tank—moisture content, oxygen content, or the type/concentration of gas? • Which instrument directly confirms that the atmosphere has reached the desired composition for safe loading of cargo vapors? • Think about which device is routinely used to monitor the progress of purging/inerting until the target atmosphere is reached.

✅ Before You Answer

• Verify which instrument measures oxygen concentration versus moisture (dew point). • Confirm which device is specified in tanker practice for deciding when gassing up is considered complete. • Eliminate options that primarily measure gases not central to inerting/gassing-up criteria (e.g., methane or CO2 in this context).