How much air should be delivered to the last open crosscut when places are driven up to 200ft without a connection for air flow?

Delivering the appropriate amount of air to the last open crosscut is critical for ensuring adequate ventilation in mining operations. In this context, the standard recommendation for air flow is that when work areas are extended up to 200 feet without an additional connection for airflow, it is necessary to supply at least 12,000 cubic feet of air per minute.

This volume of air is established based on the need to maintain a safe and breathable atmosphere by diluting harmful gases, such as methane or carbon monoxide, and providing sufficient oxygen for miners. This standard is formulated from conditions that consider the size of the area, the number of workers, and the operations being conducted in that section of the mine.

While other figures may be used for different lengths of travel or circumstances, 12,000 cubic feet per minute is aligned with safety protocols endorsed by regulatory bodies and industry best practices for this specific situation.