Bar Check Test

If a portable, battery-operated echo sounder is to be affixed to the side or bottom of the workboat to detect the water depth or seabed profile, the echo sounding result must be calibrated after the set-up by a bar check test to determine its accuracy. The test is simply conducted by a diver to measure the vertical distance of the seabed from the echo sounder by the use of a steel measuring tape with a plumb or heavy weight at the end, to determine the actual depth and fine-tune the echo sounder readings to eliminate its discrepancy.