A dirt separator includes a separating chamber defined by an outer wall, the separating chamber having a longitudinal axis; an air inlet into the separating chamber; and a shroud comprising a screen through which air is able to flow out of the separation chamber. The shroud further includes a shroud skirt extending about one end of the shroud, the shroud skirt being fixed to the rest of the shroud at a first, fixed edge, and having a second, free edge. The skirt shroud is formed of a deformable material and includes a plurality of ribs formed on a surface of the skirt.