When considering the scale of the rock massif to solve a specific rock problem, it is necessary to consider the structure of the massif within this scale (volume). If the structure is homogeneous within the scale of the massif, the solution can use existing ideas about the properties of rocks in the massif and the scale effect. A homogeneous massif can be composed of micro-heterogeneous “mother” elements. In this case, consideration of rock strength characteristics is associated with statistical characteristics considered in laboratory tests of rock properties. This mathematical apparatus can be important during the selection of rock massif that could be appropriative enough for location of fallout shelters for protection of civilian population against the effects of Nuclear Weapons.