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MNM Underground Mines Check-in / Check-out System

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Metal and Nonmetal Underground Mines
MSHA is issuing this alert to draw awareness to the importance of having an effective Check-in/Check-out system. The implications of not knowing how many people are underground, or who they are, is vast. Each tag represents a human life. In day-to-day operations, your Check-in/Check-out system ensures blasting underground can take place without exposing miners to high risk hazards that include oxygen deficiency, gases and blast concussions. In the event of an emergency situation, it provides a method to ensure all workers are accounted for, and may trigger the deployment of mine rescue teams for missing workers.

Best Practices
• Every person entering the underground operations must ensure they have placed their personal tag on the tag board before descending underground.
• Someone should be designated to check the tag board to confirm everyone from the previous shift has checked out.
• Every miner that reaches surface must ensure they remove their personal tag from the tag board.
• The supervisor in charge of blasting should ensure the check-in /check-out board is cleared before allowing the blast.
Your mine’s check-in /check-out system cannot be taken lightly. Lives depend on the system being used accurately and consistently.
30 C.F.R.§ 57.11058 Check-in, check-out system.
Each operator of an underground mine shall establish a check-in and check-out system which shall provide an accurate record of persons in the mine. These records shall be kept on the surface in a place chosen to minimize the danger of destruction by fire or other hazards. Every person underground shall carry a positive means of being identified.