Welcome to one of the most significant technological breakthroughs in Wildland Fire Service history. A world's first ever 'TOTAL' Engine Pressure (EP) calculator, both in the Apple (iOS) and Android phone app versions and mechanical slide-rule formats, to simplify the required mathematical processes in which you, as a driver/operator, are accountable under NFPA 1002: Not only are you expected to retain and effectively demonstrate the required requisite knowledge to perform the necessary procedures to engage any pump on any fire apparatus, but also mandated to estimate the TOTAL Engine Pressure to ensure your actions: 'Produce an effective fire stream at the rated flow of the nozzle.' ...under ALL conditions. ...or STOP ALL PROGRESSION as the fire apparatus maximum pump pressure has been exceeded to ensure SAFETY of your crew!