WELDER WAS ASSIGNED TO A JOB IN THE CENTRAL SHOP. DURING THE SET UP, HE DISCONNECTED TWO AIR HOSES & FELT A SLIGHT PUFF OF AIR & DIRT. APPARENTLY IT ENTERED HIS LEFT EYE. NEAR THE END OF THE S HIFT, HE SOUGHT MEDICAL ATTENTION & RECEIVED A PRESCRIPTION MEDICATION FOR THE EYE. HE WAS WEARING SAFETY GLASSES.