<p>Liquid nitrogen, as a kind of ultra-low-temperature medium, has an important application in the process of fire prevention and extinguishing in the goafs. The change of ventilation conditions will affect the efficiency of liquid nitrogen fire prevention and extinguishing. Therefore, this paper builds a large-size experimental platform to study the influence of ventilation conditions on the mass and heat transfer of liquid nitrogen vaporization within a loose medium and explores the influence mechanism of the mass and heat transfer coupling effect. The results show that the mass transfer effect is the main reason for the cooling of the loose medium body, and at the same time, the cooling radius of liquid nitrogen is much smaller than the inerting radius. In addition, the wind speed showed a significant negative logarithmic relationship on the cooling amplitude and inerting time of the loose medium. Finally, the development process of heat and mass transfer coupling effect in the pore space of loose medium was explored through theoretical analysis. The study provides a basis for improving the efficiency of fire prevention and extinguishing in the mining area and helps to solve the safety and environmental problems caused by spontaneous combustion of coal left in the goafs.</p>