“…For effective risk management and obtaining reliable and accurate test results, the risk analysis tool (Ishikawa diagram), failure cause and effect analysis (FCEA), fault tree analysis (FTA), event tree, project risk analysis and risk matrix can be used [7,9,10], etc. To analyze risks, taking into account external and internal factors, special economic and mathematical methods are used [11,12]. Their use, as a rule, assumes that the failure events are statistically independent and have an accurate probability.…”