How to Figure Drop Factor
- 1). Write down the flow rate equation. The volume in milliliters (V) divided by the time in minutes (T) multiplied by the drop factor of the tubing in drops per milliliter (Df) is equal to the flow rate in drops per minute(Y) or (V/T * Df = Y).
- 2). Substitute the known variables of volume, time and flow rate. For example, the volume is 1200 mL over 360 minutes with a flow rate of 50 drops per minute (1200/360 * Df = 50).
- 3). Divide the volume by the time. In this case, 1200 mL / 360 minutes is equal to approximately 3.3 (3.3 * Df = 50).
- 4). Divide the flow rate by the quotient determined in the previous step, to figure the drop factor of the tubing used in the treatment. For the example, 50 drops per minute divided by 3.3 (Df = 50/3.3) which equals 15 (Df = 15).
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