NOVELTY - An air filtration assembly comprises a particulate filtration portion constructed and arranged to remove particulate contaminants from dirty air; and a chemical filtration portion arranged to remove chemical contaminants from the dirty air and comprising shaped adsorbent article(s) and a mass of fibrous non-woven material.    USE - For filtering an air stream (claimed), preferably for removing particulate and chemical contaminants from the intake air of fuel cells (102).    ADVANTAGE - The invention provides a contaminant-free supply of oxidant to the fuel cell or at least a supply of oxidant having a reduced contaminant level. The invention also provides sound attenuation, sound absorption or other sound suppression.    DETAILED DESCRIPTION - An air filtration assembly comprises an inlet (12) and an outlet (14), wherein the inlet is configured to receive dirty air (50) into the first filter assembly and the outlet is configured to deliver clean air (54) from the first filter assembly; a particulate filtration portion constructed and arranged to remove particulate contaminants from the dirty air; and a chemical filtration portion arranged to remove chemical contaminants from the dirty air and comprising shaped adsorbent article(s) (19) and a mass of fibrous non-woven material. An INDEPENDENT CLAIM is also included for a method of filtering an air stream comprising passing a dirty air stream to a filtration assembly via an inlet; passing the dirty air stream through the particulate filtration portion to remove particulate contaminants from the dirty air stream; and passing the dirty air stream through the chemical filtration portion to remove chemical contaminants from the dirty air; and obtaining a clean air stream from the filtration assembly via an outlet.    DESCRIPTION OF DRAWING(S) - The figure shows a power production system including a filter assembly of the invention.    Inlet (12)    Dirty air intake side (13)    Outlet (14)    Filter (15)    Clean air outlet side (17)    Adsorbent articles (19)    Dirty air (50)    Clean air (54)    Assembly of equipment (101)    Compressor (104)