Figure 27(a) Spout Height and Knee Clearance. The front edge of the fountain must extend 17 to 19 inches (430 - 485 mm) from the wall. The 27 inches (685 mm) high minimum clear knee space must be free of equipment or obstructions for a minimum of 8 inches (205 mm) extending from the front edge of the fountain back toward the wall. In addition, a minimum 9 inches (230 mm) high toe clearance space must be provided extending back toward the wall to a distance no more than 6 inches (150 mm) from the back wall. The toe clearance space must be free of equipment or obstructions.