Quality assurance (QA) or factory production control (FPC) is necessary to ensure a proper production process. The requirements of QA/FPC can result from EN and national standards, quality assurance systems, or producer-specific rules. TMT producers must ensure that the process was correct, and to ensure traceability of products. In addition to the electronic records, the material should be checked after leaving the kiln. Methods for this task must be simple, inexpensive, fast, and must provide accurate results, in order to produce a product that lives up to its design standards. Actual moisture content (MC) is an essential parameter of any quality assessment protocol of wood products. The equilibrium moisture content (EMC) in a determined climate, among other parameters, seems to be a suitable indicator for treatment intensity. As with other indicators, any correlation only applies to a specific process, kiln type, and wood species. The method includes the adjustment of a specific climate, where samples are stored, and the determination of moisture content (MC) with a sufficient accuracy. Specific climates can be adjusted in climate chambers or above saturated water-based solutions. For MC determination, both oven-dry and electrical methods are applicable, as well for factory production control (FPC). The limited accuracy of electrical measurement below 6 % moisture is to be taken into consideration. Some investigations which compare the suitability of electrical and oven-drying methods to determine MC are described. Moisture content was determined in both thermally-modified and untreated Norwegian Spruce and European beech, climatised at two moisture levels. Results showed that both electrical methods provide acceptable data for EMC in humid climate. However, the statistical analysis showed significant differences for most electric methods, compared to oven-dry method. The capacitance method provided more accurate results than resistance method, when compared to oven-dry results.

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