What is the average rate of fall for percolation calculated by?

The average rate of fall for percolation is calculated by dividing the total minutes by an appropriate factor that represents the number of measurements taken during the percolation test. In this context, when calculating percolation rates, the standard practice is to divide the total time recorded for water to drop in the test holes by six. This method accounts for the necessary adjustments to yield a rate that reflects the soil's ability to absorb water over a standardized time frame. By using six, the calculation aligns with the typical assessment protocols for soil permeability, ensuring that the percolation test results are both consistent and reliable for determining septic system suitability.