A blast machine does not run on new media. It runs on an equilibrium mixture of new additions and partly worn particles, and the shape of that distribution — not the specification on the bag — determines the finish and the intensity being delivered.

That is why durability matters more than unit price. Media that fragments early skews the mix towards fines, which the separator must remove, which means both faster consumption and higher load on the extraction system.

Dust is the hidden cost in the same equation. Fines load filters, reduce visibility in the cabinet and, in an enclosed machine, degrade the working environment. A medium that generates less dust reduces three costs at once and none of them appear on the media invoice.

The practical check is simple: screen a sample from the working mix rather than from the bag. If the distribution has drifted far from the specification, the media is either wrong for the machine or being consumed faster than the addition rate assumes.