A self contained breathing apparatus electronics system that provides a method for maximizing battery life, estimating remaining battery life and condition, insuring reliable communications between modules, maintaining reliable real-time clock (RTC), minimizing piezo interference, minimizing effects of RFI and EMI on pressure measurement, retaining consistency in the motion detection circuitry due to sensitivity to temperature changes, and provides an SCBA facemask-mounted Thermal Imaging Camera (TIC) Module and a Heads-Up Display (HUD) Module mounted inside an SCBA facemask, in one of several embodiments.