EE WAS OUTSIDE SHOP. SNOWING & RAINING. EE WAS AIR ARCING THE BLADE OF D9. THE BLADE WAS ABOUT 12"" OFF GROUND. HE WAS ON KNEES AND LIFTING HOOD TO TAKE A LOOK AT WORK WHEN A PUDDLE OF SLAG POP PED. HE WAS WORKING ALONE AND ON THE WAY HOME INTHE DARK HAD IMPAIRED VISION. WENT TO ER THAT NIGHT.