be selected based on a risk matrix like shown below, based on Mil. Std. 882. The higher the risk level, the more justification and mitigation is needed to provide evidence and lower the risk to an acceptable level. High risk should be indicated to higher level management, who are responsible for final decision-making. After this step the FMEA has become like a FMECA. Timing The FMEA should be updated whenever: A new cycle begins (new product/process) Changes are made to the operating conditions A change is made in the design New regulations are instituted Customer feedback indicates a problem Uses Development of system requirements that minimize the likelihood of failures. Development of designs and test systems to ensure that the failures have been eliminated or the risk is reduced to acceptable level. Development and evaluation of diagnostic systems. To help with design choices (trade-off analysis). Advantages Catalyst for teamwork and idea exchange between functions Collect information to reduce future failures, capture engineering knowledge Early identification and elimination of potential failure modes Emphasize problem prevention Fulfill legal requirements (product liability) Improve company image and competitiveness Improve production yield Improve the quality, reliability, and safety of a product/process Increase user satisfaction Maximize profit Minimize late changes and associated cost Reduce impact on company profit margin Reduce system development time and cost Reduce the possibility of same kind of failure in future Reduce the potential for warranty concerns Limitations While FMEA identifies important hazards in a system, its results may not be comprehensive and the approach has limitations. In the healthcare context, FMEA and other risk assessment methods, including SWIFT (Structured What If Technique) and retrospective approaches, have been found to have limited validity when used in isolation. Challenges around scoping and organisational boundaries appear to be a major factor in this lack of validity. If used as a top-down tool, FMEA may only identify major failure modes in a system. Fault tree analysis (FTA) is better suited for "top-down" analysis. When used as a "bottom-up" tool FMEA can augment or complement FTA and identify many more causes and failure modes resulting in top-level symptoms. It is not able to discover complex failure modes involving multiple failures within a subsystem, or to report expected failure intervals of particular failure modes up to the upper level subsystem or system. Additionally, the multiplication of the severity, occurrence and detection rankings may result in rank reversals,