Abstract: A method for improving air filtration efficiency of a fibrous nonwoven media and a fibrous non-woven air filtration media having improved filtration efficiency. The method includes applying to fibrous material at least about 0.05 wt. % based on a total weight of the fibrous material of chemical treatment comprising an alkoxylated silicone copolymer. The chemical treatment is effective to provide an improvement in an E3 filtration efficiency value of the filtration media as tested according to ASHRAE 52.2 of about 20% or more compared to an E3 filtration efficiency value of fibrous material devoid of any chemical treatment.