Safety and reliability

Reliability is generally described as a component characteristic as opposed to safety, which is seen as a system characteristic. Principally the mle is that reliability is only considered as a component characteristic if the environmental conditions are clearly defined. The question is whether the same challenges regarding reliability for components in complex dynamic systems apply to safety. 

First of all the question arises if a component environment is entirely specifiable. For many, especially solely mechanical components, we can assume normative and always consistent environmental conditions. But if we observe reliability over time, we find influential factors that are hard to specify or often only known as a result of negative experiences. This applies for material compatibility for the materials cupper or zinc or stainless steel and salt environment, which can turn into a galvanic element at a certain concentration. As a consequence it could lead to corrosion and other chemical reactions. 

This measure can quickly lead to a high ASIL because rear axles are responsible for stabilized driving of the vehicle. 

The aim of system development is mainly to describe the design in a neutral way, so that the reliability first and foremost becomes relevant in the design of the components. Software design often discusses reliability but ISO 26262 does not formulate concrete requirements for systematic methods in order to determine the reliability of software. However, for mechanic components the same statements apply as those formulated for the vehicle system and its integration into the vehicle. 

For the electronic we often find very tight intersections, particularly because the evaluation of the hardware architectural metrics (ISO 26262, part 5, chapter 8) as well as the evaluation of safety goal violations due to random hardware failures (ISO 26262, part 5, chapter 9) are based on the failure probability of electric components or occurrence probability of random hardware errors. Section 4.4.2.S covers such quantitative safety analyses in detail. Often, chapter 7 part 5 of ISO 26262 is overlooked, which covers the correct dimensioning and verification of 

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Part 4 Reliability and safety of complex systems (German only) (July 1995) Warehousing of Chemicals Loss Prevention Bulletin 088, IChemE, Rugby, U.K., August 1989. 

The range of problems that probabilistie teehniques ean be applied to is vast, basieally anywhere where variability dominates that problem domain. If the eompo-nent is eritieal and if the parameters are not well known, then their uneertainty must be ineluded in the analysis. Under these sorts of requirements, it is essential to quantify the reliability and safety of engineering eomponents, and probabilistie analysis must be performed (Weber and Penny, 1991). In terms of SSI analysis, the main applieation modes are ... 

Gertman, D. L., and H, S. Blackman, 1994, Human Reliability and Safety Analysis Data HancMjook, Wiley, New York, NY. 

The first practical silver—zinc battery was developed more then 60 years ago. Since then, primary and secondary silver—zinc batteries have attracted a variety of applications due to their high specific energy, proven reliability and safety, and the highest power output per unit weight and volume of all commercially available batteries. However, they find very limited use in commercial applications, because of their high price and limited cycle life. Development of a battery separator which will improve the performance and life of zinc based alkaline cells has been... 

RRS. 2000. Process Safety Management Training Course. Risk, Reliability, and Safety Engineering. Houston, Texas. 

Risk, Reliability and Safety Engineering (RRS), of Feague City, Texas (www.rrseng.com) was contracted to write this guideline. The principal RRS authors of this guideline were ... 

VARICOMP. A method for evaluating the interface between fuze expl conponents in which it can be determined by statistical analysis and testing that the reliability and safety of a fuze expl train can be predicted at high-confidence levels with a small number of tests. This is done by varying the sensitivity of different expls that are then substituted into the expl train of interest to determine the safety and reliability limits under a penalty test situation... 

In heat recovery applications there can be a large number of feasible plant configurations. After the configuration is optimized based on steady state considerations (which may not be an easy problem), the evaluation of the effectiveness of various control schemes can be performed. The dynamic plant operation must be evaluated in terms of economics, regulation, reliability, and safety over a broad range of operating regimes. 

The LWR, CANDU, and graphite reactors are the major producers of electricity from nuclear energy. When compared on the basis of cost, reliability, and safety, they are competitive. The PWR is the most widely used LWR, but there are also many BWRs in use. In 1990, there were 16 CANDUs operating in Canada where they were developed, with several in other countries as well. 

ENCRESS European Network of Clubs for Reliability and Safety of Software... 

C — Lapin, A., Oxygen Compatibility of Materials, Reliability and Safety of Air Separation Plant, Bulletin de L lnstitut Internationale du Froid, Annexe 1973-1, pp. 79-94. 

Safety and reliability of chemical process plants are such important issues, they deserve the best techniques to prevent problems occurring. To minimize risks resulted from operating problems and hazardous events, process system safety and reliability analysis is often employed. This is a rigorous approach undertaken to improve system reliability and safety. The approach consists of three main tasks hazard identification, risk estimation, and risk control. 

Chamber lifetime is among the considerations that would have a significant impact on cost, reliability, and safety. Were the U.S. Army to further investigate any of the detonation-type technologies examined in this report, a structural integrity assessment for the number of detonation cycles that could be anticipated for the life of the detonation chamber with respect to the types of munitions to be processed would give important information. Likewise, a failure modes and effects analysis for each type of detonation system under consideration would be highly desirable. 

Recently, the management of large nuclear and fossil fuel thermal power plants have stimulated the development of diagnostic systems, in order to improve primary coolant quality. Such improvements constitute indirect tools for increasing the plant reliability and safety, both depending on the corrosion of the structural materials. 

A schematic flow diagram that underlies the processes of reliability and safety assessments is depicted in Fig. 1.6. The results should be used at different levels to aid in operational and strategic planning. 

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