Safe Practices for the Use of the Sheathed Explosive Charge in Underground Coal Mines.
Verakis HC; Mainiero RJ; Mulhern JJ
Proc 13th Conf on Explosives & Blasting Techniques Miami Florida 1987 Feb; :115-130
This paper describes applications in coal mines where it would be advantageous from a safety standpoint to fire unconfined shots. However, the firing of mudcaps or other unconfined explosive charges in underground coal mines is not permitted because of the explosion hazards associated with methane gas and coal dust. Present safety regulations in title 30, code of federal regulations prohibit such practices. Recently, MSHA proposed revised coal mine regulations for the approval and use of sheathed explosives for public comment. Preceding the proposed regulations, the Bureau of Mines developed a prototype sheathed explosive charge and demonstrated in numerous tests that it would not ignite atmospheres of methane and coal dust. Subsequent to the development work, some studies were conducted by MSHA and the Bureau of Mines in an operating coal mine to demonstrate the performance and safe use of the sheathed charge. The development work and experimental studies are presented with respect to safe, practical coal mine applications.
Proc. 13th Conf. on Explosives & Blasting Techniques, Miami, Florida, Feb. 1-6, 1987, PP. 115-130