The SMI Miner’s Helper Extensometer is a single-point extensometer designed for underground mining to measure rock strata separations or roof sag. It uses a reflectorized rod that activates when a user-defined amount of movement occurs, providing a visual indication of ground movement.

The extensometer is installed in a borehole in the mine roof or wall. When rock movement exceeds a user-specified threshold, the reflectorized rod activates, visually indicating the extent of movement. This helps miners monitor ground stability and prevent collapses.

• Single-Point Monitoring: Measures rock strata separations or roof sag at a specific point.
• Visual Indication: Uses a reflectorized rod for clear, user-defined movement alerts.
• Robust Design: Built to withstand harsh underground mining conditions.
• Simple Mechanics: Easy to install and monitor without complex equipment.

It is ideal for mining companies, safety managers, and ground control teams who need a reliable, simple tool to monitor roof sag or rock movement in underground mines to enhance safety and prevent collapses.