Fault prevention analyses

Adherence to GMP guidelines already offers a sound basis for avoiding microbial contamination or other products mishap. However, in some cases it is also wise to carry out special manufacturing process fault prevention analyses. Similar approaches have already proven their worth in other industrial sectors, such as automobile and foodstuffs. The conceptual basis for such studies are FMEA, Failure Mode and Effects Analysis-Fehlermoglich-keits- und -Einflussanalyse (DIN 25 448), and the HACCP concept (Hazard Analysis Critical Control Points, (Pierson, 1993). 

Fault prevention analyses can yield valuable information about processes of which the cosmetic industry has little experience. They can also be used to effect optimization of processes that repeatedly yield unexplained contamination. Fault prevention analyses, as applied to the cosmetics industry, are not only concerned with health aspects of cosmetics manufacture, but include exploration of faults that could incur economic losses and damage to company image. 

Each of the many potential sources of risk considered during fault prevention analysis requires individual... 

The estimated impact is then compared to hazard acceptance criteria to determine whether the consequences are tolerable without additional loss prevention and mitigation measures. If the identified consequences are not tolerable, the next step is to estimate the ffequency/probability of occurrence of the identified failure modes leading to loss of containment. For simple cases, frequency estimates are combined with consequences to yield a qualitative estimate of risk. For complex cases, fault tree analysis is used to estimate the frequency of the event leading to the hazard. These estimates are then combined with the consequences to yield a measure of risk. The calculated risk level is compared to a risk acceptance criterion to determine if mitigation is required for further risk reduction. 

HAZOP and What-If reviews are two of the most common petrochemical industry qualitative methods used to conduct process hazard analyses. Up to 80% of a company s process hazard analyses may consist of HAZOP and What-If reviews with the remainder 20% from Checklist, Fault Tree Analysis, Event Tree, Failure Mode and Effects Analysis, etc. An experienced review team can use the analysis to generate possible deviations from design, construction, modification, and operating intent that define potential consequences. These consequences can then be prevented or mitigated by the application of the appropriate safeguards. 

This fault tree analysis (FTA) of the wet pipe sprinkler system for the building at, , outlines the primary, secondary, and command failures of the system that would prevent it from extinguishing a fire in the facility. 

Part V will cover several techniques for working on prevention that apply multiple factor models. Multiple factor models may use quantitative or qualitative analysis. Statistical techniques, such as factor analysis, multiple regression analysis and other multivariate methods may be useful. Fault tree analysis, failure mode and effects analysis and other approaches help identify characteristics that together can lead to undesired events. 

In ANSI/ASSE Z590.3—2011, the Prevention through Design standard, Addendum G comments on only eight hazard analysis and risk assessment techniques, intentionally. They are Preliminary Hazard Analysis, What-If Analysis, Checklist Analysis, What-If Checklist Analysis, Hazard and Operability Analysis, Failure Mode and Effects Analysis, Fault Tree Analysis, and Management Oversight and Risk Tree (MORT). It was also said in Z590.3 that ... 

The production of effective recommendations for the prevention of recurrence is unlikely to be straightforward in these complex accidents and incidents so that techniques such as Fault Tree Analysis (FTA) may be required to analyse the causal sequences. In addition, creative thinking techniques such as brainstorming and systems thinking may be required to generate a suitable range of recommendations. 

The event tree analysis is similar to the fault tree analysis and enables management to prevent loss producing events as a result of risks within the system. The event tree analysis is a predictive method of analyzing risks. 

Curcuru, G., Galante, G.M. La Fata, C.M. 2012. Epistemic uncertainty in fault tree analysis approached by the evidence theory. Journal of Loss Prevention in the Process Industries 25 667-676. 

A number of other analytical tools such, as what if, checklist, hazard and operability study (HAZOP), failure mode and effect analysis (FMEA), or fault-tree analysis can be used to determine possible process breakdowns. You then can design prevention/controls for the hkely causes of these unwanted events. 

Several of FM s Loss Prevention Data Publications (1, 17B, 17C) discuss the concept of triply-redundant, fault-tolerant, high-reliability hardware/software systems for manufacturing operations. Risk analysis and systems reliability research is currently underway to develop better guidelines for the design and application of reliable process control systems. 

Preventive maintenance refers to inspection, test and varied maintenance activities performed in the specified state of the devices so as to discover fault signs and to avoid fault occurrence. Reliability-Centered Maintenance (RCM) follows a basic thread performing a function and fault analysis of the devices, understanding the fault consequence... 

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