A sounding stick is a stick which is inserted into a fuel tank to the bottom and the level of wetness indicates the height of fuel, the same as an oil dip stick.  You can calibrate the number of gallons you have put in the tank by marking lines on the sounding stick.  In the context of the guidance, it would be good to have at least a marking when the tank is 90% full.
 
When beginning a cruise, some boaters take readings of their available fuel using a sounding stick that they have calibrated to the particular tank they are sounding. Fuel gauges may provide a useful reference -- if they are working properly -- but often they are not accurate enough to determine true fuel-level rates. The irregular shape of many tanks can cause false readings. A tank with a triangular section and pointed end down might appear half full when it is really only a quarter full. After powering for a protracted period of time, a sounding stick makes the boater able to determine how many gallons per hour they are consuming to achieve a particular boat speed in those particular conditions.

 

Close Window