OWNER/OPERATOR OF SANDBLASTING CO. WAS SANDBLASTING AREAS OF THE NEWLY CONSTRUCTED PRODUCTION PLANT. INJURED WAS OPERATING A SELF-PROPELLED MANLIFT WEARING BOTH HIS PROTECTIVE HELMET AND RESPIRATOR. HIS HELMET MAY HAVE OBSTRUCTED HIS VISION, CAUSING A JUDGEMENT ERROR ON LOCATION OFMANLIFT'S BASKET. WHEN ADJUSTING THE BASKET, HE BECAME PINNED BETWEEN BASKET & I-BEAM, CRUSHING.