strength of bonding between the particles or fibres at the surface of a panel and the material below (uncoated panels) or between the coating material and the underlying panel (coated panels), paneeli pinnal olevate osakeste või kiudude ja allpool oleva materjali (katteta paneelid) või kattematerjali ja selle all oleva paneeli (kaetud paneelid) vahelise sideme tugevus
