From Reckon It:
185Graph is a 1.85 graph based fire sprinkler hydraulic calculation software program specifically designed to graph sprinkler demand vs. water supply. It calculates base of the riser demand with the Grid Calculator, Tree Calculator or Head by Head Worksheet and will plot these demands against any water supply. Water supplies can be adjusted for friction loss, elevation and/or hose streams.
185Graph has compact, single form modular design with all data input and output ergonomically displayed on the same form. Instantly determine a sprinkler system's weakness by inspecting the detailed pressure loss data, and develop the most appropriate recommendations for improvement. With routine use, you will develop an instinctive sense of "what is adequate" and "what improvements are required". Quickly change sprinkler heads, pipe diameter, density, area, skew, pump size, etc. Immediately see the effect of lowering storage or reinforcing the sprinkler piping and/or water supply.