This Part of EN 335 gives guidance on the application of the hazard class system, as defined in Part 1 of EN 335, to wood-based panels: plywood, particleboards, oriented strand boards, fibreboards, cement-bonded particleboards in relation only to the biological agencies that can attack wood-based panels over a duration sufficient to result in deterioration. This Part is to be used in conjunction with Part 1 of EN 335. Annex A (informative) provides additional guidance on the use and suitability of wood-based panels, preservative treatment and/or finishing within a given hazard class.