## 3 Proposed Methodology
### Fuzzy FMEA Implementation  
Once the main elements of a system have been identified, an FMEA analysis is performed. For this purpose, a simplified variant of FMEA is proposed. The objective of this phase is to characterize the criticality of each previously identified failure mode by obtaining MTBF and MTTR values. Through the Fuzzy FMEA process, critical failure modes will be identified by determining the RPN (Risk Priority Number) derived from the fuzzy inference process, which is explained in the following paragraphs. To conduct Monte Carlo experiments during RAM experiments, it is essential to select parameters that reflect the ambiguity of MTBF and MTTR values, which are usually defined in the FMEA stage. In the absence of detailed probabilistic functions that explain the behavior of these parameters, this is achieved through estimation based on expert judgment, which derives the distribution parameters that capture, according to their assessment, the inherent variability. Furthermore, the FMEA likelihood ratings can be used to define MTBF ranges, such as when a failure is rated as \"likely within a year\", which indicates a lower MTBF compared to a \"rare\" failure. This approach allows for a more accurate representation of the uncertainty in simulation parameters. The structure of the format for the FMEA analysis is shown in Figure 2.  
The table contains the following headers and their respective descriptions:  
Equipment: The name of the equipment or component being evaluated. Tag No. : The tag number or identification of the specific equipment. Arrangement: The type of arrangement or configuration of the equipment. Failure Mode Description: The description of the failure mode that may occur in the equipment. FMEA Workshop--2011: Information obtained from the FMEA workshop in 2011, including the values of MTTF (Mean Time To Failure) and MTTR (Mean Time To Repair) in years and hours respectively, along with their minimum and maximum values. FMEA GNLQ Review 2011: Data from the FMEA GNLQ review in 2011, including the values of MTTF and MTTR with their minimum and maximum values. FMEA Workshop--2014: Information obtained from the FMEA workshop in 2014, including the values of MTTF and MTTR in years and hours respectively, along with their minimum, median, and maximum values. Data Source and Comments (2014): Data sources and relevant comments from 2014 that provide additional context or clarifications about the presented data. In this structure, the relevant information about the FMEA (Failure Modes and Effects Analysis) for different components and their failure modes is captured, facilitating the evaluation of the reliability and maintainability of the equipment. The MTTF and MTTR values are recorded using the triangular fuzzy numbers approach. This method facilitates the collection of the data required for the FMEA, allowing for variability throughout the asset lifecycle, as well as accommodating uncertainty or lack of complete knowledge about them. Once these fuzzy numbers are collected, inference rules are applied to generate crisp values for both parameters and an RPN value. This RPN value enables the prioritization of failure modes, which will be selected for further analysis in the RAM stage. These values can then be used as parameters for executing the subsequent RAM analysis. The RPN (Risk Priority Number) is the fundamental criterion for determining the priorities of failure modes. It is essential to calculate the RPN with precision and clarity. This indicator is determined as the product of three factors: the occurrence, which estimates how often failures may occur; the severity, which assesses the impact of these failures on the system; and the detection, which measures the likelihood of identifying the failure before it occurs. However, this definition is often laden with subjectivity and uncertainty. For the calculation of the RPN, an adapted process of that suggested by [36] was used. A fuzzy inference model based on rules for determining a fuzzy representation of the RPN was implemented.