In the Metro Exodus, you will be able to track many different locations - some of them will be polluted by toxic air and you will need to use a gas mask to survive. However, the effective use of a gas mask requires regular filter changes - but where do you get them from? We answer on the following page of this guide.
Pick up filters scattered in the game world
Very often in locations that require the use of a gas mask (mainly in buildings), you can find filters hidden in cabinets, etc. It is, therefore, a good idea to search the room in order to replenish damaged stockpiles.
Craft Gas Mask Filters
The optimal idea is to create filters for the gas mask using the backpack or a workbench. For a small price in resources, you can create new filters, which often help in getting through toxic locations in the game. But always try to have an extra supply of filters, because you never know what awaits you in the world of Metro!