Article deals with issues connected with protection of facilities containing selected dangerous substances from deliberate actions of persons intending to steal, damage, or destroy its protected assets. First part of article contains analysis of requirements resulting from generally binding legislation that deals with physical and object security of these companies. It lists advantages and disadvantages of existing approaches that utilize quantitative or qualitative methods intended for evaluation of protection level of existing or designed security systems, which consist of mechanical means of protection, alarm systems and response force. Software tool SatANO, output of research activities of Faculty of Special Engineering at University of Zilina in Zilina, is described in conclusion of this article. Its purpose is to allow quantitative evaluation of technical effectiveness of government strategic object security systems.