Laserfiche WebLink
E <br />Safety Factor <br />1 2, <br />i <br />1 7 J <br />01 <br />fl <br />er <br />o) <br />Figure 3. Pillar factor -of -safety for the mains area, (top) Niosh recommended coal strength of <br />900 psi and development loading, (bottom) worst case scenario using minimum coal strength of <br />600 -psi and considering load transfer from the longwall area. <br />• <br />Maleki Technologies, Inc. Page 10 <br />Factor of Safety Distribution on the B Seam, Development <br />In Situ Coal Strength = 900 psi <br />Factor of Safety Distribution on the B Seam, Retreat <br />In Situ Coal Strength � 600 psi <br />