The real danger when casting is from the oxides that get skimmed off when fluxing/cleaning the metal. The vapor pressure of Pb at normal casting temperatures is very low. A fan would certainly be helpful to minimize breathing the oxides , but good hand washing afterwards is also a good idea and doesn’t take any sort of extra equipment.
On a related note I bought some of the D-lead soap. I can’t swear it’s any better than regular soap in terms of removing lead, but I’ve never seen a better soap for removing that black grime you get when cleaning guns or working on motors. It even removes ink. To me it would be worth buying even if you never handle lead at all.