Abstract: On August 27, 2011, Employee #1 and #2, maintenance workers, were sent to the attic to determine the source of a water leak. It was determined that the water was leaking from the 1-inch PVC pipe on the side of the air handler unit. They initially used a 20-ft plumber's snake, but were unsuccessful. They then poured liquid drain opener into the pipe. The drain opener reacted violently with something in the pipe, and caustic liquid sprayed in Employee #1 and #2's faces. Their vision was blurred and it was difficult to evacuate from the remote section of the attic where they were working. Once out of the attic, they separated and went to different water sources to flush their eyes. Both had serious burns to their eyes and faces, with Employee #1 having the worst of the two. Both employees were hospitalized and remained out of work for more than one week.