OmniFire Friction Loss Calcuator
Scroll to the bottom for screensnots, a demo video, and links to Omnimedix in the iTunes App Store.
My dad was a fireman so I gew up around the fire
station, and I was a fireman long before I was into EMS. Even though my
focus has shifted more towards EMS now, the fire service will always be
special to me. From the time I was old enough to climb into the truck alone,
I wanted to "drive the big red truck", and when I finally got the chance to,
I realized there was more to being a driver than just getting the truck to
Being able to pump the truck once you get on scene is just as important as driving, and fireground hydraulic calculations are just as important - and challenging - as EMS driprate calculations. For that reason, various methods of quick-reference friction loss calculation were developed, including sllide rules, quick-reference charts, the "hand method", and the good ole' "rule of thumb" (watch the guy on the end of the nozzle and he will give you a "thumbs up" or "thumbs down" to turn the pressure up or down) to quickly determine the pump discharge pressure. Ultimately, they are all based on our good friend "FL=CQ2L", which has pretty much become the universal formula wherever you go.
While the math isn't easy, the biggest problem becomes remembering the coefficient values of C, followed by trying to run the formula, remembering that Q is gallons divided by 100 then trying to square it and... well, when fire is blowing out of the house at 3am, you really don't have time to do that calculation... until now.
OmniFire takes the values you enter for the required nozzle pressure, the GPM setting on your nozzle and the length of the hoseline and combines them with preloaded values of "C" to run the calculation for you. Since it only has one menu, you can enter the information and run the calculation in less time than it takes the guy from the back seat to pull the hose to the front door. Guaranteed. If you're using a smooth-bore nozzle, it even incorporates GPM=29.7D2√NP give you the flow rate.
It allows for multiple calculations to be entered for multi-line operations and will save your calculations until the program is reset to allow you to run friction loss calculations for the various hoselines on the truck, and reference them later. OmniFire isn't flashy and fancy... it doesn't display the output of formulas in gauges or have a diamond-plate background, because those things are distracting and don't make it work any better. If you want something flashy, go polish the chrome on the truck... if you want something that is simple and works quickly, you're gotta get OmniFire.
Since our apps are for sale worldwide, the user has the option of selecting US units (GPM, feet, inches, & psi) or SI/Metric units (LPM, meters, mm, & kPa) to accommodate for users outside of the US. Since I'm in the S, the default setting is US units, but it can be quickly changed, and OmniFire remembers that setting for every calculation until the app is closed.
DIRECTIONS: From the home screen, tap "Add Line" to begin a calculation. "Hand line" is the default setting (although you can select "Supply Line", which disables the nozzle pressure entry). Enter the required/desired nozzle pressure, tap on the hose diameter you're using, and enter the hose length and flow rate for your nozzle. If you have a gated wye, manifold, water thief, etc, in the line, enter the appliance loss your department uses, then hit "calculate" and Omnifire will show the nozzle pressure, friction loss, appliance loss, and total pump discharge pressure for the line.
If you're using a smooth-bore nozzle and aren't sure of the flow rate, tap the "?" logo, and tap on the orifice size and enter a nozzle pressure; "calculate" will figure the flow rate and "add to line" will add it to your line. If you enter a flow rate greater than 350GPM, OmniFire detects it, and automatically adds 25psi to the value shown to account for it being a master stream, so you don't have to add it again.
Tap "Add Line", and the information from that line is added to the home screen. If you change something in the line, you can edit the settings, or you can tap "Add Line" from here to run the calculation again for an additional line.
If you think OmniFire is pretty cool, give us some good feedback on the app store and share it with your crews. But hey, if you think it sucks, feel free to let me know, and I'll work on improving it. If that's the case, whatever you do, please let me know that before posting a bad review on iTunes, cause that bad review stays forever (even after I fix whatever you tell me is broken) I'm a fireman just like you guys, and I work on the apps on my days off to give my brothers another tool in the toolbox.
Omnifire demo video: Click here if video doesn't load