PERFORMANCE OF IN-LINE MOISTURE METERS

The performance of in-line moisture meters, which are integral tools for monitoring final MC and carrying out redry programs, was evaluated with respect to meter accuracy, precision, and ability to recognize wet streaks. Results, based on meter performance when using a single sensor head and kiln-dried white fir dimension lumber, indicate that potential accuracy for low and high frequency in-line meters, as measured by 95 percent prediction intervals, is plus or minus 2. 9 percent and plus or minus 3. 3 percent respectively, versus plus or minus 3. 8 percent and plus or minus 4. 0 percent for hand-held resistance and power-loss meters. Due to the presence of wet streaks and pockets in white fir lumber, these results represent one of the worst cases for moisture meter performance. Additional factors affecting the accuracy of in-line and hand-held meters are discussed.