Search results for " FMECA"

Fuzzy FMECA analysis of radioactive gas recovery system in the SPES experimental facility

2021

Abstract Selective Production of Exotic Species is an innovative plant for advanced nuclear physic studies. A radioactive beam, generated by using an UCx target-ion source system, is ionized, selected and accelerated for experimental objects. Very high vacuum conditions and appropriate safety systems to storage exhaust gases are required to avoid radiological risk for operators and people. In this paper, Failure Mode, Effects, and Criticality Analysis of a preliminary design of high activity gas recovery system is performed by using a modified Fuzzy Risk Priority Number to rank the most critical components in terms of failures and human errors. Comparisons between fuzzy approach and classic…

ANALISI DI RISCHIO DELL’IMPIANTO SPERIMENTALE “SELECTIVE PRODUCTION OF EXOTIC SPECIES” (SPES) DELL’INFN DI LEGNARO

Il progetto di ricerca denominato EURISOL (European Isotope Separation On-Line Radioactive Ion Beam Facility), che vede coinvolti i principali laboratori di ricerca nucleari europei, è rivolto allo studio di progettazione e fattibilità di un impianto per la produzione di fasci di nuclei radioattivi posizionati nella cosiddetta “terra incognita” della carta dei nuclidi. Lo scopo principale è l’esplorazione della materia esotica (nuclei caratterizzati da un eccesso difetto di neutroni), con le sue possibili implicazioni nell’ambito della ricerca di base della fisica nucleare, nelle applicazioni in campo medico e dell’astrofisica, e ancora nello studio dei materiali utilizzati nei reattori nuc…

Improved FMECA for effective risk management decision making by failure modes classification under uncertainty

2022

Failure Mode, Effects, and Criticality Analysis (FMECA) is a proactive reliability and risk management technique extensively used in practice to ensure high system performance by prioritising failure modes. Owing to the limitations of traditional FMECA, multi-criteria decision-making methods have been employed over the past two decades to enhance its effectiveness. To consider the vagueness and uncertainty of the FMECA evaluation process, an interval-based extension of the Elimination et Choice Translating Reality (ELECTRE) TRI method is proposed in the present paper for the classification of failure modes into risk categories. Therefore, ratings of failure modes against risk parameters are…

RPN safety analysis to reduce the risk of malpractices in high dose rate brachytherapy

2013

A new fuzzy rule-based assessment model is proposed to evaluate the risk priority number in the Failure Mode, Effects, and Criticality Analysis (FMECA) method to rank component failures and human errors from the medical staff, leading to potential radiological over-exposure of patients during high-dose-rate brachytherapy treatment. The obtained results are relevant for a range of causes that have a reasonable probability of producing significant adverse outcomes. Thus, recommendations are provided for procedures and safety devices to reduce the occurrence of radiological over-exposure accidents. This method can solve the problems in conventional FMECA applications and improve the safety and…

The FTOPSIS method to support FMECA analyses

2016

This paper proposes an approach based on multi-criteria decisional methods to manage the results derived from reliability analyses. In detail, this paper proposes ranking the failure modes of a system when analyzed with failure modes, effects and criticality analysis (FMECA) using the technique for order preference by similarity to ideal solutions (TOPSIS). To better manage the uncertainty of evaluations made under the differing criteria, the TOPSIS method is applied in its fuzzy version (FTOPSIS). When the method is applied to a case study, the results highlight the main possible critical faults and supply fundamental information to take into account during the scheduling of maintenance ac…

FMECA Analyses of radiological over-exposure accident to patients in brachytherapy

2012

This paper presents safety analyses of accidental events which can involve patient during High Dose Rate brachytherapy treatment in over-exposures. The study has been performed by using the well-known techniques FMECA modified by Fuzzy logic theory. Moreover, fuzzy HEART methodology was employed in order to evaluate human error probabilities for each treatment stage. The obtained results, aimed to obtain a list of the deviations with a reasonable probability to produce significant adverse outcomes, provided some recommendations for procedures and safety equipments to reduce the occurrence of radiological over-exposure accidents.

FMECA Application in Tomotherapy: Comparison between Classic and Fuzzy Methodologies

2022

Accident analysis in radiotherapy highlighted the need to increase quality assurance (QA) programs by the identification of failures/errors with very low probability (rare event) but very severe consequences. In this field, a Failure Mode, Effects and Criticality Analysis (FMECA) technique, used in various industrial processes to rank critical events, has been met with much interest. The literature describes different FMECA methods; however, it is necessary to understand if these tools are incisive and effective in the healthcare sector. In this work, comparisons of FMECA methodologies in the risk assessment of patients undergoing treatments performed with helical tomotherapy are reported. …