Sounding Holding Tanks

Sounding tanks is a way to determine how much fluid is in the tank.  This can be done by using the following steps.  It may be somewhat different depending on the substance inside the tank.

• Ensure the vessel is stable enough for an accurate sounding.  Being docked in sheltered waters is preferred.  If the ship is listing, significantly trimmed (less common), or in an unstable sea state, this may produce an inaccurate sounding.
• Don protective equipment suitable for the sounding.  This can commonly include eye protection, gloves, and a mask, but will depend on the substance in the tank.
• Locate the appropriate access port and the dipstick suitable for this tank.  Ensure the dipstick is clean as this process can introduce contaminants into the tank.
• Lower the dipstick completely into the tank and pause for a moment to allow the fluid to settle.  Raise it back up slowly being careful not to spill.
• Record the measurement, restow the dipstick, and clean up the area if necessary.