Why does the Dyson V15's whole-machine filtration matter for pet dander?

The [Dyson V](https://www.amazon.com/s?k=Dyson+V&tag=wehavethat-20)15 traps 99.97% of particles down to 0.3 microns, which matters because standard filters let microscopic allergens like cat dander pass back into the air. Its sealed system keeps what goes into the bin from escaping, making it worth the extra cost for pet owners or allergy households.