The range of flame detectors sometimes degrades on its outer edge as it reaches the maximum range. To account for this, an Edge Efficiency may be added, which is the range of the detector along its edge, as a percentage of its maximum range.
The image below shows a detector's FOV with a maximum range of 200 feet and an Edge Efficiency of 70% equating to 140 feet along the outer edge before the FOV starts curving towards the center line.
Enter a value of "70%" in the Edge Efficiency text box for your model and continue to the next property.
Tutorial 10 - Figure 03 - Edge Efficiency for a FOV, top view pictured