As a rule, shredders use wet scrubber for air filtration because of their low risk of explosion.

In the future, however, clean air limit values will descend further and alternative solutions may be required in order to achieve the desired levels of air quality.

Keller relies on dry operating systems for purifying exhaust air, which effectively reduce emissions. Cyclones are used for the pre-separation of coarser particles.

The exhaust air from shredders is mostly in dust category St-1. Explosion isolation of the connected ductwork from the protected collectors is generally sufficient. For higher dust explosion categories, additional constructional explosion protection measures can be employed such as fast-closing valves or extinguishing barriers.