Working on the heavy media prewet screen. 6x6 beams were cracked in half. Screen sees a lot of water, so it was rusty. Took the screen off deck of prewet to be grinded. Was wearing safey glasses and hard had with light attached and also had another light there. Had dust rag, steel could have been on rag when he wiped face. Did not get medical treatment until 8/17/09.