Dust is no good to any living organism.
Cat litter sand seems to be the source of dust.
This is why i set up a fully automatic filtered ventilation on the cat litter box.
The essence of the system is an active coal filter. The filter will minimize dust and odor from cat litter box.
1. A closed cat litter box. Preferably one that comes with an active coal filter.
2. time relay (to put a delay on fan running time (like 1 or 2 minutes ok?!))
3. power adapter.
4. Magnetic switch.
That is it!