THE INJURED EE AND THE WITNESS WERE REMOVING AN OBSTRUCTION INT HE DISCHARGE CHUTE FROM E126 ELEVATOR TO THE ALKALI TANK. THE END OF THE AIRLANCE THEY WERE USING WAS PLUGGED AND BROKE LOOSE, B LOWING ALKALI DUST OUT OF THE INSPECTION HOLE THEY WERE WORKING IN. THE DUST ENTERED THE INJURED EE LEFT EYE. BOTH EE WERE WEARING SAGETY GLASSES ONLY.