Inductive safety analysis

In part 9 there is only one indication for the differentiation of the deductive and inductive safety analysis. The inductive safely analysis is described as bottom-up approach. It is considered that known causes of failure and their unknown failure effect are examined. ISO 26262 mentions Failure-Mode-and-Effect-Analysis... 

The inductive safety analysis is described as a bottom-up method. It investigates unknown failure effects starting with known failure causes. Today the FMEA is the basic analysis method at all. It has been developed for almost twenty years in different ways. The classical form sheet analysis (blank table form analysis) can be called a truly inductive safety analysis, whereas the cause in this context is often also determined deductively. This means that potentially unknown causes are examined. AU new FMEA methods start with the function, a task or characteristics of the basic parts and search for potential causes, which could lead to malfunction, wrong tasks or to deviations of required characteristics of the basic parts. The next step is the determination of error propagations so that the failure effect can be determined. 

In the deductive safety analysis all possible variances and consequently the entire specifiable space should be analyzed. In the inductive safety analysis the specified elements are considered at the respective horizontal abstraction level and the possible error influences or impacts are evaluated. As a result a systematic falsification of the specified space could lead to completeness regarding possible error behavior. Influences and combinations, which the developer cannot imagine or not systematically evaluate, are also not verifiable. The characteristics of the product should be ensured at the end of such horizontal development activities after their verification. 

See Deductive Reasoning, Inductive Reasoning, and Inductive Safety Analysis for additional related information. 

A job safety analysis had been carried out, and as a result a supervisor was apparently required to be on-site during the operation, but problems arose in implementing this. In addition the worker who recovered said he had had no induction training. Finally, the safety superintendent identified differences between the main contractor and a subcontractor over implementation of the safety management system. 

For this paper we treat hazard assessment as a combination of two interrelated concepts hazard identification, in which the possible hazardous events at the system boundary are discovered, and hazard analysis, in which the likelihood, consequences and severity of the events are determined. The hazard identification process is based on a model of the way in which parts of a system may deviate fi om their intended behaviour. Examples of such analysis include Hazard and Operability Studies (HAZOP, Kletz 1992), Fault Propagation and Transformation Calculus (Wallace 2005), Function Failure Analysis (SAE 1996) and Failure Modes and Effects Analysis (Villemeur 1992). Some analysis approaches start with possible deviations and determine likely undesired outcomes (so-called inductive approaches) while others start with a particular unwanted event and try to determine possible causes (so-called deductive approaches). The overall goal may be safety analysis, to assess the safety of a proposed system (a design, a model or an actual product) or accident analysis, to determine the likely causes of an incident that has occurred. 

Fault Tree Analysis A system safety analysis technique used as an inductive method (top down) to evaluate fault or failure events. 

Methods and techniques for measurement, sampling, and analysis Types, sources, and characteristics of hazards, threats, and vulnerabilities Hazard analysis, job safety analysis and task analysis methods Qualitative, quantitative, deductive, and inductive risk assessment methods Risk-based decision-making Risk-based decision-making tools... 

The automobile associations like VDA and AIAG have described the essential methods in this context. Standards had been improved in other industries based on their requirements. FMEA is according to ISO 26262 an inductive method for the safety analysis. However, all FMEA methods in the automobile industry are widely based on the sequence of failure cause, failure and failure effect. The kind of measures to improve the product or avoid, mitigate errors, or their propagation had been defined and applied differently in the standards. The evaluation factors of failures are called as follows ... 

A second topic of inductive and deductive safety analysis, we also differentiate between qualitative and quantitative safety analysis. The quantitative safety analysis should also consider the frequency of failures, but for both the fault modes and effecting errors need to be analyzed. Generally, the norm says of course that the quantitative safety analysis is used to fulfill the quantitative metrics from part 5, Chaps. 8 and 9. 

Chapter 7, part 4 addresses the system design, the technical safety concept and their verification, which should be derived from the functional and technical safety requirements. Therefore, in requirement 7.4.3.1 the inductive (for all ASILs) and deductive (for the higher ASILs) safety analysis is required. In this context of product development on system level it is primarily a matter of the analysis of systematic failure. In one indication (note 1) it says that a quantitative analysis can support the results. 

However, the model-based safety analysis should first be seen as addition for the classic analysis methods. It would be worth considering seeing the model-based safety analysis preferably as deductive analysis and the classic FMEA further on as inductive analysis. Therefore, the systematic approach of consistent system engineering can again be applied from the vehicle level all the way down to the silicon stmcmres and the software development. 

Even so, some hazards may not be readily identifiable, and there are techniques which can be applied to assist in this respect. These include inductive analysis, which predicts failures - failure modes and effects analysis (FMEA) is one of these job safety analysis (JSA) is another. Inductive analysis assumes failure has occurred and then examines ways in which this could have happened by using logic diagrams. This is time-consuming, and therefore expen-... 

See Deductive Reasoning, Deductive Safety Analysis, and Inductive Reasoning for additional information. 

Figure 21.2 illustrates how the starting point, the directions and the scope of each method fit into the accident-analysis framework of Chapter 6. Two of the methods. Fault tree analysis and Comparison analysis are deductive in that they start with the unwanted event. They proceed by analysing the underlying incidents and deviations (Fault tree analysis) or contributing factors (Comparison analysis). Several of the methods are mainly inductive in that they start with a deviation and proceed by studying the effects of this deviation. This applies to HAZOP, Failure mode and effect analysis. Event tree analysis and CRIOP, although they also have a component of causal analysis. Coarse analysis and Job-safety analysis start with the hazard and use a combination of inductive and deductive analyses. 

Circuit capacitance and inductance, including the values of these parameters for interconnecting wiring, are integral parts of the overall analysis. It is not always possible to assure that the system will be maintained as designed with only approved intrinsically safe components and with circuits of the capacitance and inductance as originally installed. For this reason, intrinsically safe systems are used primarily at locations where there are sufficiently trained personnel to assure that the intrinsic safety of the system is always maintained. 

A number of tests are available for the chemical characterization of medical device materials to establish material safety and biocompatibility. These tests include infrared analysis, aqueous and non-aqueous physicochemical tests, high-performance liquid and gas chromatography, atomic absorption spectroscopy and inductively coupled plasma spectroscopy, and a variety of mechanical/physical tests. 

Zanker B, Schneeberger H, Rothenpieler U, Hillebrand G, Miner WD, Theodorakis I, Stangl M, Land W. Mycophenolate mofetil-based, cyclosporine-free induction and maintenance immunosuppression first-3-months analysis of efficacy and safety in two cohorts of renal allograft recipients. Transplantation 1998 66 44-49. 

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