| 1. | Drill bolt holes into roofs at specified distances from ribs or adjacent bolts. |
| 2. | Force bolts into holes, using hydraulic mechanisms of self-propelled bolting machines. |
| 3. | Remove drill bits from chucks after drilling holes, then insert bolts into chucks. |
| 4. | Test bolts for specified tension, using torque wrenches. |
| 5. | Position safety jacks to support underground mine roofs until bolts can be installed. |
| 6. | Position bolting machines, and insert drill bits into chucks. |
| 7. | Rotate chucks to turn bolts and open expansion heads against rock formations. |
| 8. | Install truss bolts traversing entire ceiling spans. |
| 9. | Tighten ends of anchored truss bolts, using turnbuckles. |