A toner dam maintenance process and system model the amount of toner mass at a toner cleaner blade, and apply a corrective procedure, such as insertion of a paperless copy into the print job mid-job or immediately prior to cycle out, to replenish the toner mass at the cleaner blade to maintain lubrication and reduce cleaning failure. The device is provided with: a device body, a storage container which accommodates blister packages in a stacked state, and a dispensing member which can dispense the accommodated blister package. The oxygen storage amount is computed using an storagerelease rate set according to the exhaust air-fuel ratio and catalyst temperature, etc.