Dust Off versus Surface Prep
For getting dust off, why is everyone telling the OP to use volatile and flammable solvents? General deck cleaning and dust removal should be done with a weak soapy solution and rinse.
The is a difference between dust/dirt and grease/wax and residual adhesives. If the OP has dust/dirt, use a weak soapy solution with some scrubbing action and then rinse well with water, allow to dry thoroughly, then follow with the paint prep solvent for what ever paint system that you are using. If there are areas of residual adhesive, grease, or wax, hit them with a cloth soaked in acetone or mineral spirits first. No need to do whole desk in acetone or MS .
The paint prep materials do have high flash solvents in them and surface etching materials, but they also contain a small amount of "paint/tie coat" that will bond to the cleaned deck and help the topcoat bond better. You need to do this step, as NOLAsailing points out, to ensure adhesion of the topcoat.