Measure the distance between any two nozzles on the spray boom and record in INCHES in the box to the right:

If your sprayer has only 1 nozzle - measure the width of the spray pattern when sprayed on the ground at the correct height and record this value in INCHES in the box to the right.

Determine a calibration distance and record that distance in FEET in the box to the right:

Using a stopwatch, Determine the amount of time required to travel the calibration distance while in the desired gear and RPM setting or at a constant walking speed.

Record this value in SECONDS in the box to the right:

With water in the spray tank and the sprayer running at the desired RPM and pressure setting (out of gear, of course), collect the output from each nozzle for one minute - do one nozzle for one minute, record the value, and move on to the next nozzle (this is GPM or Gallons Per Minute for each nozzle). After recording each individual output - calculate an average nozzle output per minute for the sprayer by adding all nozzle output amounts together and dividing by the total number of nozzles.

Record the average output in GALLONS in the box to the right: You probably will need to convert from ounces or milliiters into gallons.

To Convert:
1 Gallon = 3785 millileters = 128 ounces
1 ounce = 0.0078 gallons
1 milliliter = 0.000264 gallons