(450 mm in length and 450 mm in width). Forty millimeter-thickRSTIB mats were prepared with a target density of 200, 250, 300and 350 kg/m3. After forming, the mats were loaded into a press.Two pieces of Teflon sheets were placed on the top and bottomsurfaces of the mat to prevent the boards from sticking onto thehot plates during pressing. To improve the production and qualityof the thick boards, a CGM-30 high frequency (HF) press was cho-sen. HF is a type of electromagnetic (EM) radiation with frequencies1–400 MHz