THE EE WAS SENT TO VERIFY FLOW OF MATERIAL THRU THE PREHEAT TOWER. WHEN HE LOOKED IN THE SAMPLE PORT, AN AIR CANNON WENT OFF CAUSING A POSITIVE CONDITIOHN. THE EE TOOK A SHORT CUT IN THAT HE D ID NOT FOLLOW PROPER PROCEDURE IN WEARING A FACE SHIELD AND DID NOT DISABLE THE AIR CANNONS.