What action should be taken immediately after noting the tank level during sounding?

The most appropriate action to take immediately after noting the tank level during sounding is to record the level. Recording this information is crucial because it creates a permanent log of the tank's status, which is essential for monitoring and analysis. Accurate recordings help in tracking changes in tank levels over time, compliance with safety regulations, inventory management, and making informed decisions regarding operations.

Cleaning off the sounding tape, while it may seem important for maintenance, does not address the immediate need to document the reading. Notifying the crew or inspecting nearby valves could be necessary actions under specific circumstances, but they are not the immediate priorities right after taking the measurement. The immediate focus should always be on accurately capturing the data before any other actions are taken.