1. Visual Inspection: Carefully examine the fiberboard to ensure uniform thickness and density. Also check for defects such as damage, delamination, bulges, or carbonization at the edges and corners.
2. Water Immersion Test: If possible, cut a small piece of fiberboard and immerse it in 20°C water for 24 hours. Observe the thickness change and the appearance of small bulges during immersion to determine its water resistance.
3. Odor Test: Judge the fiberboard's odor by smell. A stronger odor usually indicates a higher formaldehyde release, thus affecting the board's environmental performance.