A floor standing and environmentally isolated external fusing module dockable with a first external module surround frame surrounding a xerographic toner image marking module is provided and includes (a) a fusing apparatus for receiving from the xerographic toner image marking module a copy sheet carrying an un-fused toner image thereon to heat and permanently fix the toner image onto the copy sheet; (b) a second external module surround frame for surrounding and isolating fusing volatiles from the fusing apparatus to prevent the fusing volatiles from contaminating an imageable surface and wire charging devices in the xerographic toner image marking module, the second external module surround frame having a second set of sheet-path interface and module-to-module docking devices for docking with the xerographic toner image marking module; and (c) floor standing casters mounted to a bottom of the second external module surround frame for movably supporting the floor standing and environmentally isolated external fusing module.