Abstract: ON JUNE 7, 1985, EMPLOYEE #1 DIED INSIDE A 6.3 MILLION GALLON CAPACITY GASOLINE STORAGE TANK. THE TANK WAS HALF-FILLED WITH REGULAR LEADED GASOLINE. THIS EMPLOYEE WAS PERFORMING AN "INTERNAL PAN TANK INSPECTION" WHICH PRIMARILY INVOLVES WALKING ON A FLOATING ALUMINUM COVER INSIDE THE TANK AND CHECKING THE CONDITION OF THE RUBBER SEALS WHICH ARE PRESENT WHEREVER THE FLOATING COVER MUST MOVE PAST A STATIONARY SURFACE. THE EMPLOYEE WAS APPROXIMATELY HALFWAY AROUND THE PERIMETER OF THE 150 FOOT DIAMETER TANK WHEN HE PASSED OUT. HE WAS WEARING A SCBA ON HIS BACK, BUT WAS NOT WEARING THE RESPIRATOR FACEPIECE. ANOTHER EMPLOYEE, ON THE TOP OF THE TANK, HEARD EMPLOYEE #1 FALL OVER, BUT COULD NOT ATTEMPT A RESCUE BECAUSE HE HAD NO RESPIRATOR FOR HIS OWN USE, AND EMPLOYEE #1 WAS NOT HOOKED TO A LIFELINE OR EQUIVALENT DEVICE.