HE WAS INSTRUCTED BY HIS SUPERVISOR TO WELD A GURARD FOR THE DRY SCREEN, THE WAS NOT PROVIDED WITH ANY TYPE OF PROTECTIVE EQUIPMENT FOR THIS JOBTASK. HE PROCEEDED TO WELD FOR APPROX.30 MINUTES AFTER COMPLETING THE JOB HE WENT BACK TO HIS REGJOB OF OPERATING THE LOADER. AT APPROX. 7PM HE BEGAN TO FEEL BURNING IN BOTH HIS EYES.