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In the process of designing a fire safety system for underground mines, computer fire models can be used to analyse and estimate the consequences of fire scenarios for the evacuation process and the safety of mineworkers. The models need to be fed with data, some of which is stochastic in nature. Recent literature addresses the need for a computationally effective methodology for introducing uncertainties in the input parameters of fire and evacuation models to improve safety in underground mines. This research paper presents the results obtained from a methodology that implements Monte Carlo simulation, which follows the normal distribution of the fire load and the pre-movement time uncertainty to generate multiple scenarios that are simulated in a 3D model to show the propagation of combustion products through the mine ventilation network. These results are then used to estimate the fractional effective dose (FED) of fire combustion products in workers, and the available safe egress time (ASET) and required safe egress time (RSET), which can highlight the safety issues in the evacuation process. To demonstrate the model, a case study of the SASA-R.N. Macedonia lead-zinc mine was used in which 50 variations of scenarios were simulated. The results from the simulations are analysed and potentially harmful fire scenarios highlighted. In addition to being able to identify potentially dangerous fire scenarios, the model can also help in the process of conducting fire risk assessment and in improving the evacuation system in the case of an underground mine fire.

Reversal ventilation is one of prevention methods against fire hazard in underground mines, but it is not recommended for the mines where methane is present. The authors introduce the new method of reversal and by conducting numerical simulations they prove that it allows to keep methane at the acceptable level during miners escape. However, it requires connection between the subnetworks of the main ventilation fans. It was also shown, that by using the method some escape routes will be shortened. It is possible to apply this method in the mines where the fans and stoppings are fully controlled across the full range of their operating parameters. The findings are important for underground mines, as well as for surface facilities where air control or smoke control is managed by two or more fans.

A significant quantity of available hard coal reserves in the area of Upper Silesian Basin in the Czech Republic occurs below the areas where surface mine subsidence is unacceptable or may be only minimal. An effort is made to mine these reserves by means of a new, mining method yet not approved for the joint-stock company OKD, a.s., namely a special modification of the continuous mining method Room & Pillar. The main objective is to eliminate the mentioned surface restraints by leaving stable pillars of coal to support the overlying strata. For this reason, CSM Sever, Mining Plant 2 of OKD, a.s. realised a test run to verify the problems arising during mining at high depths, when implemented in an area where it has never been used before. The article is based on published in Journal of Mining Science in the year 2015. In the article, the authors are concerned with the description of stress-strain monitoring of pillars left after test operation, including its continuous evaluation and evaluation of important operating conditions and activities. The objective of monitoring is to gather sufficient information to assess whether the Room and Pillar extraction method can be used in areas where there is a risk of rockburst.