Abstract: A dust containment cap for use in a printing device to be supplied with finely pulverized toner which is susceptible of becoming airborne and contaminating surrounding areas employs two brushes arranged in the toner supply opening such that they completely fill the opening but permit the insertion of the neck of a toner bottle to be inserted through them for depositing new toner. Toner that becomes airborne below the brushes is impeded by the brushes from escaping from the opening. The brushes may be installed at downward angles so that together they form a "V"; toner inadvertently spilled on the tops of the brushes gravitates to the bottom of the "V" whence it may be dropped through by agitating the bristles.