An apparatus and method that determines toner age in a printing apparatus. The method can include placing an imaging surface cleaner in contact with an imaging surface. The method can include placing a toner patch on the imaging surface. The method can include rotating the imaging surface in a process direction. The method can include measuring a frictional interaction between the imaging surface cleaner and the imaging surface as the toner patch passes the imaging surface cleaner. The method can include determining whether toner should be purged based on the measured frictional interaction. The method can include purging the toner if the toner should be purged.