Electrostatic air filter

A filter for an electrostatic precipitator comprising: a plurality of spaced-apart, electrode films having electrical conductivity, arranged to be alternately powered at high and low electrical potentials, each of said electrode films having a leading edge, a trailing edge and two opposing side edges therebetween that extend in the direction of airflow; and first and second pluralities of spaced-apart, rigid isolation members bonded to each of the leading and trailing edges of the plurality of electrode films respectively, wherein each isolation member is bonded, via a substantially continuous, preferably flat, surface thereof, to at least some of said leading or trailing edges, thereby fixing the electrode films in the required spaced-apart arrangement thereof.