Image forming apparatus having removable duct and filter

An image forming apparatus comprising:

• an image forming portion configured to form a toner image on a sheet at a first position by using toner containing a parting agent;
• a fixing portion configured to thermally fix, at a second position, the toner image formed on the sheet by said image forming portion;
• a duct, including a suction port provided opposed to a sheet feeding path between the first position and the second position, configured to discharge air to an outside of said image forming apparatus;
• a filter, provided at the suction port of said duct, configured to collect particles of a predetermined particle size resulting from the parting agent;
• a projecting portion projecting from an outer peripheral surface of said duct;
• and
• a holder configured to hold said filter, said holder provided with an engaging portion to engage with said projecting portion and being detachable from said duct,
• wherein said duct includes an edge surface connecting between an inner peripheral surface and the outer peripheral surface, and
• wherein said filter is compressed by said edge surface and said holder.