An Analysis of Modern Fuel Moisture Measurement and the Development of a 100-hour Dead Fuel Moisture Sensor

In the ever-evolving modern fire environment, accurate and automated measurement of the moisture content of dead and down woody fuels, often referred to as dead fuel moisture content (DFM), is becoming increasingly important. This study aims to address several issues with current DFM measurement methods and practices. First, commercially available, automated DFM sensors have been limited to the 10-hour time lag and have not been properly evaluated for accuracy. Second, a standard fuel analog has not been identified for 100 + hour time lags. Finally, alternative wood species for standardized, large fuel analogs have not been identified or tested. In order to perform necessary tests to solve these issues, an environmental chamber—which produces constant temperature and humidity conditions—was used to set equilibrium moisture content (EMC) values for fuel analogs to absorb and desorb moisture toward. Electronically sensed values are compared against gravimetric values recorded by a highly accurate scale inside the chamber. Additionally, initial developments on a potential automated sensor for 100 + hour time lag fuels are presented.