Percent of Grade
One way of describing a ramp or sloped surface is to describe it in terms of percent of grade.
Percent of grade is the ratio of the vertical rise to the horizontal distance: Rise over Run.
In trigonometry the decimal equivalent of this ratio is known as the tangent. Tan = Opposite over Adjacent
Calculating Percent of Grade
Most forklift manufacturers publish gradeability specifications for their equipment in terms of percent of grade.
In order to calculate the percent of grade for a ramp, measure the Rise and the Run and calculate the decimal equivalent of the ratio of Rise over Run:
Percent of Grade = (Rise divided by Run) x 100
Percent of Grade = ( 4' divided by 22') x 100
Percent of Grade = 0.18 x 100
Percent of Grade = 18%