THE INJURED WAS INSTALLING APPROX. 1"" THICK INSULATED MAT BETWEEN WET PLANT ATTRITIONER DISCONNECTS. HE USED A UTILITY KNIFE TO DO THE FINAL TRIM WORK TO FIT MAT AROUND HANDRAIL POST. THE KNIF E SLIPPED AND CUT EE APPROX 2"" ABOVE HIS RIGHT KNEE CAUSING A LACERATION.