Which of the following is a key benefit of rock dusting in coal mines?

Rock dusting in coal mines serves several essential safety functions, with one of the primary benefits being the reduction of fire hazards. When coal dust accumulates in the mine, it can create an explosive environment, especially when combined with an ignition source. By applying rock dust to the surfaces in a mine, the flammable coal dust is effectively diluted, thereby lowering the risk of dust explosions. This practice enhances overall mine safety by creating a non-combustible layer that can smother potential fires and prevent them from escalating.

The other choices, while they might seem related to operational improvements, do not directly address the primary safety purpose of rock dusting. For instance, increasing ventilation is more associated with improving air quality rather than fire prevention, and equipment efficiency and operational costs deal with the broader operational aspects of mining rather than the immediate safety protocols. Therefore, the most relevant answer regarding the key benefit of rock dusting is its role in reducing fire hazards.