What is the formula for friction loss in a fire hose?
FL = C * (Q / 100) ^2 * L / 100 Where FL = Friction Loss in PSI, C = friction loss Coefficient (or friction loss factor), Q = Flow rate in GPM, and L = hose Length.
How do you use the hand method?
59 second clip suggested8:22Hand Method for Calculating Friction Loss for Firefighters – YouTubeYouTubeStart of suggested clipEnd of suggested clipSo let’s get started with the hand method. What you’re going to do is imagine your hand left hand orMoreSo let’s get started with the hand method. What you’re going to do is imagine your hand left hand or right hand it doesn’t matter and you’re going to put the number 12 in the center of your palm.
What is the PSI of a fire hose?
Attack fire hose should be service tested to a minimum of 300 psi or a service test pressure marked on the hose. Supply fire hose should be service tested to a minimum of 200 psi or a service test pressure marked on the hose.
How do you calculate nozzle pressure?
12 second clip suggested7:53Pump Operator Training Series – Part 2 “Calculating Nozzle Flow”YouTube
How do you use friction method for hand loss?
Using the hand method, for each 100-foot length of 1¾-inch hose flowing 200 gpm, the friction loss is 48 psi: 2 x 4 x 6 = 48 psi. For a 3-inch supply line flowing 300 gpm, the friction loss per 100-foot section would be 9 psi: 3 squared equals 9 psi. Memorizing this much simpler than it sounds.
How is fire pump pressure calculated?
For example, if you have a 40,000-square-foot building that is all ordinary group 1, the calculation would be 1,500 x 0.15 (density) = 225 + 250 (hose demand) = 475 gpm total for the fire pump. If the structure has multiple hazards, the hazard with the highest gpm calculation dictates the pump size.
How much PSI is in a fire hydrant?
Fire hydrants are flow-tested at a residual pressure of 20 psi; therefore, firefighters should understand the typical flow rates of fire hydrants at that pressure.
What is the PSI in nozzle?
These settings correspond to a particular discharge orifice, or tip size. In order for a conventional nozzle with a fixed opening to operate at the correct nozzle pressure of 100 psi, the proper gpm flow must be supplied.