How can spontaneous combustion in coal mines be prevented?

Controlling ventilation and reducing combustible materials is vital in preventing spontaneous combustion in coal mines. Proper ventilation ensures that any heat generated by oxidation or other exothermic reactions is dissipated, thereby lowering the risk of reaching combustion temperatures. Effective airflow can dilute the concentration of combustible gases and help maintain lower temperatures, which is essential in the prevention of spontaneous ignition.

Moreover, minimizing the presence of combustible materials—such as coal dust or other flammable debris—further reduces the potential fuel available for combustion. Keeping the mining environment clean and ensuring proper practices to manage waste materials are essential for maintaining a safe working atmosphere.

The other options do not address the critical factors related to the behavior of coal and its propensity for spontaneous combustion. Increasing temperature creates a higher risk rather than reducing it, while installing additional lighting does not mitigate the risks associated with heat generation and flammable materials. Using low-grade materials does not inherently eliminate the risk of spontaneous combustion either, as even lower-grade coals can combust under the right conditions if combustible materials and heat are not managed properly.