V313 melamine-faced chipboards are moisture proof because they contain urea melamine formaldehyde glue. The boards are coloured green and are submitted to heavy testing. Pieces of chipboard are submerged in water for 3 days, then put in a freezer for 10 days at a temperature of 12 degrees Celsius and finally dried for 3 days at 70 degrees Celsius. This cycle is repeated three times. After stabilization at room temperature, the swelling may only amount to a maximum of 8%.