Dust is of course huge problem and not only in PCB printing !
As mentioned by the above short answer, static electricity is the major cause of the presence of dusts in the air of your plant.

1- if possible, you must work in fully coçnf-ditioned air at 20-22°C with an hygrometric percentage of 75 to 85%.

2 -If possible, try to have a higher pressure of air inside of your plant in amanner the dust remain"glued" on the walls if I can say so !

3- on the press, you need 3 anti-static bars = one after the feeder (if some) or after hand feeding. One other at the level of the squeegee/flood bar and the last one at the way out of the press (before the entrance in the drying or curing unit).

You must also have a tool to measure the charge of static electricity, to send orders to the bars, through computer may be, in a manner to send the exact opposite current to "neutralise" the charge.

4- There are antistaic products that can be added in the inks, conductive oçr protective. Take care of the amount as they often countains silicons.

5 - Some manufacturers of squeegee blades - FIMOR for example - supply also blades that are partially conductive and can also eliminate some of this static electricity.

6 - Your press and dryer must be in contact with the earth and not isolated.... Evident = the remanent static electricity must be "driven out", not kept inside.

7 - Before printing the circuit, if possible, to wipe or to roll it between a system with rolls "in love with dust" and an anti-static bar can also help a lot..

If you do some or best, all of those actions, I don't think you will have any more problem with static-electriicity.... Then dusts !
MC