The charcoal filter by A.I.T. France clean the exhaust of solvent vapors. Each filter cartridge is supplied with a label on which you can write the date of commissioning and the date of the exchange of the cartridge. The timing of replacement of the current filter will depend on the amount of activated carbon in the cartridge. The filter cartridge with 25g of activated charcoal should be replaced approximately 3 months after commisioning.