The first step in performing a FMEA is to organize as much information as possible about the system concept, design, and operational requirements. By organizing the system model, a rationale, repeatable, and systematic means to analyze the system can be achieved. The failure effect is the severity of the consequence of the failure mode. There are many possible sensing device alternatives such as alarms, gauges, and inspection. The determination of the failure probability can be performed qualitatively or quantitatively.
Quantitative analysis relies upon numeric estimation of failure probability using data sources.
Qualitative probability assessment is applied with the use of subjective estimation for probability values. 2.2.1.1 Qualitative Failure Probability Determination Qualitative probability of failure is determined using probability categories selected by the analyst. The risk associated with different failure modes or system components can be ranked to show the relative affects on safety. The criticality matrix is important for risk management because it provides an effective visual risk communications tool. The acceptance criteria shown in Table 1 is used as an example this may vary based on the decision of risk management.