• GPM: Gallons Per Minute
• GPA: Gallons Per Acre
• mph: Miles Per Hour
• W: Nozzle spacing (in inches) for broadcast spraying
• Spray width (in inches) for single nozzle, band spraying or boomless spraying.
• Row spacing (in inches) divided by the number of nozzles per row for directed spraying.

PWM Calculation: To size nozzles, take the desired GPA Rate and divide it by .70 in order to target a 70% duty cycle.

For Example: If the target rate is 10 GPA, the equation would be 10 / .7 = 14.3. This is the GPA to look for in a tip chart.