Vasylets' O. Giving basis to the method of outburst hazard prognosis of the opening steep coal seams according to the change in time of the gas emission speed.

Area of mine seam, being uncovered by field working in conditions of Central Donbass Region. Motivation of the method of emission danger prognosis in the place of opening of steep seams by crosscut according to change in time and velocity of gas emission out of blastholes or boreholes drilled into coal seam. The complex method of the researches was used: analysis of mines' practice work, analysis of registration cards of gas-dynamic phenomenon and of researches on emission danger prognosis; experimental researches in developing and uncovering openings of mines; statistic processing of measurement data; using law of probability and method of minimum risk; mining-experimental and industrial examinations. In the area of emission danger of the part of steep coal seam, which is being uncovered by crosscut, the more sharply decrease in time of velocity of gas emission out of blasthole is set out experimentally, and it is reliably registered during three minutes after measuring the initial velocity of gas emi ssion. The number of blastholes (not less than five) and the schemes of their disposition for provision of reliable prognosis of emission danger of steep coal seam while its opening by the crosscut were grounded. It is experimentally found out the numerical value of temporary criterion of emission danger of the seam KB based on the measure of velocity change of gas emission during three minutes after change of initial velocity of gas emission , when device ПГ-2МА reading are taken every 30 sec., and length of measuring board is equal to all subgrade drilled capacity of seam. At Кв<5,0 on the part of seam in the place of opening there is no emission danger. At Кві5,0 the situation is assessed as emission dangerous even if it is received in the single blasthole. The new method of gas emission prognosis in the place of opening by crosscuts providing minimum probability of I type mistake is developed; this can raise safety of work. The worked out "Vremennoje rukovodstvo…" is approved by the Central Committee for the control of gas-dynamic phenomenon and is recommended by Makeevsky Scientific Research Institute for implementation into the branches of industry. According to decision of the "Central Committee…" before implementation of the way of prognosis into "Instruction…" it is allowed to open emission dangerous coal seams according to "Vremennoje rukovodstvo…" . This method is introduced in conditions of mines of Industrial Corporation Artyomugol.