friends house about 26 x 30 ft sq... hot water radiator heat... we think the radiators srir up a ton of dust... very hard to keep the house clean... will a few room size humitafiers putting a mist of water in the air help keep the dust down ? Tks richard

Not likely. Forced air heat would most certainly stir up a lot of dust, but hot water radiators don't physically blow air. Your friend can try removing the covers from ALL the radiators and vacuum them out as much as possible.