I have a dry darkroom in a laundry room. I use the room from fall to spring and therefore the house heater is used which can lower humidity. Adding some humidity does wonders. I add humidity by placing pastic food containers of water on top of the vents and running a constant furnace fan. Poor man's humidifier. Before a DR session wipe down all surfaces to remove dust. I use a LPL 670 or Leitz 1C enlarger for most work. Both are exellent at avoiding dust once you dust the negative and install in the enlarger head. Enlargers like a B-22 have gaps around the carrier allowing dust to migrate from outside to inside the head. With new negatives I never have issues. With negatives which have been used pulling them from plastic sleeves can add a charge. I like the folder type negative sleeves.