Soundfast

Soundfast is a term used to describe a system aboard ships used to remotely sound tanks without the use of manual labor. Soundfast systems generally employ the use of a submersible level sensor or similar in a tank overflow or vent line. When the tank reaches the level of the sensor, the sensor signals the control electronics that the tank is full.

This is an improvement over manually sounding the tanks with the weighted line (rope) and a sounding tube. Per Code of Federal Regulations, sounding tubes are also required when a soundfast system is installed in case the soundfast system fails.