Ee & coworker were lifting a 200#, 20' long ash rake up west side of rotary. As it was being placed on rotary floor, ee felt his back go out. This caused him to release his grip on ash rake. He sat down: when he tried to stand up, he fainted, fell & hit his nose & forehead on coal mill exhauster fan base. He cut his nose & bruised his forehead. He was taken by ambulance