Knowledge zone

Reverse PFMEA – Basic Principles

Of course, carrying out PFMEA does not end work on the development of the process. An obligation is, for example, to conduct risk analysis reviews. The article discusses the most important elements of the little-known RPFMEA method.

RPFMEA – goals

Reverse PFMEA is still a little known analysis in Poland, the name of which is usually translated as reversed PFMEA. The course itself has not yet received standardized international descriptions (e.g. authorized by ISO or IATF), but its conduct can be based on the QSB + standard issued by GM and PSA.

The primary goal of RPFMEA is to reassess the topicality of the previously conducted process analysis. During the RPFMEA, errors, causes, effects, preventive and control actions as well as SOD scores are confirmed as defined in the PFMEA. It is, like the regular PFMEA analysis, the work of an interdisciplinary team, which is based on the observation of the production line and the so-called related documents such as: process flow diagram, job instructions, process monitoring records, etc.

Basic principles of working with RPFMEA

The essence of the RPFMEA analysis can be checked up to four points:

1. It is an operation carried out to a large extent on a stand next to the machine. The RPFMEA analysis is not done in its entirety “at the desk”, as its purpose is to verify the correctness (validity) of the risk assessment – therefore, free access to the process is needed.
2. RPFMEA includes, among others review that all possible errors and causes have been defined. An important element of the analysis is a properly selected team, whose technical knowledge (in the field of materials science, technologies used, etc.) and practical experience will allow for the assessment of the completeness of the analysis.
3. In RPFMEA, the assessment of the effectiveness of control and preventive activities should be based on “hard”. To implement this element of analysis, statistical data are used, among others MSA results, internal deficiency reports, complaint records, etc.
4. RPFMEA analysis should include verification and – if possible – reduction of RPN (new approach: AP) based on current data. Due to the wear of machines, gaining experience by employees, the company’s development in the field of TPM, etc., the conditions in which the process takes place are constantly changing – therefore the values ​​of the Sev, Occ and Det indicators may change

An important principle of conducting the RPFMEA analysis is the participation of at least one “external” person, ie a person who was not involved in the PFMEA of the examined process and may not even know it. The role of such a person is to identify new risks to “fresh”, which is to lead to an even better “sealing” of individual phases of the process. The role of the maintenance department representative cannot be overestimated (employees of the Maintenance Office, also outside RPFMEA, are more and more often involved in risk analyzes [1]) – he is to ensure that the team does not damage the process equipment during the experiments.

Organizational assumptions

And the last feature of working with Reverse PFMEA – because it is a form of audit, it should also look like organizational. The QSB + standard referred to at the beginning requires a detailed schedule of RPFMEA analyzes to be developed, ensuring that all processes will be audited within a specified period. In order to standardize the approach, a checklist should also be developed, thanks to which all the questions that are important from the point of view of risk analysis assessment will be asked each time – this document, after being completed, later acts as a report, so important for each audit.

Related Sources:

Mikołajczyk J., The use of FMEA analysis in the modern concept of maintenance – RCM, “Zeszyty Naukowe Politechniki Poznańskiej” 2013, No. 61.

Tomasz Greber [PROQUAL]