System safety adoption

The traditional scheme is complicated by the fact that some antidepressants exhibit characteristics of more than one class. For example, clomipramine, a tricyclic antidepressant (TCA) with side effects and toxicity similar to other TCAs, works more like the selective serotonin reuptake inhibitors (SSRls). Similarly, venlafaxine and duloxetine, which are usually grouped with the atypical antidepressants, have a side effect and safety profile comparable to the SSRls. Although a classihcation system based on mechanism of action offers some advantage (see Table 3.7), even this scheme is limited by the fact that antidepressants that work in the same way may have widely divergent side effect and safety profiles. In the following discussion, the traditional classification system is adopted. Although fraught with problems and inconsistencies. 

Several texts include hazard analysis and risk assessment decision matrices. Every matrix I found has been adopted from those included in what was originally known as Military Standard—System Safety Program Requirements, MlL-STD-882. Its most recent version is now named Standard Practice for System Safety, MIL-STD-882D, 2000. Influence of that standard will be obvious in the remainder of this chapter. 

INFLUENCES ENCOURAGING ADOPTION OF SYSTEM SAFETY CONCEPTS 325... 

WHY SYSTEM SAFETY CONCEPTS HAVE NOT BEEN WIDELY ADOPTED... 

At least one other author expected a more widespread adoption of system safety concepts, beyond the use by the military and aerospace personnel, and nuclear facility designers. He also had to recognize that... 

In this chapter, it was my purpose to (a) recognize the many successes that have been achieved through the application of system safety concepts, (b) establish that fundamental system safety concepts can be applied by generalists in safety practice, (c) outline The System Safety Idea, and (d) encourage generahsts who have not adopted system safety concepts in their practices to commence the inquiry and education to do so. 

I sincerely beheve that we generalists in safety practice can learn from system safety successes and be more effective in our work through adopting system safety concepts. Their application in the occupational and product safety settings would result in significant reductions in injuries and illnesses. 

The RMS Titanic was a splendid British ocean liner which sank on her maiden voyage on the night of the 14-15 April 1912 after a collision with an iceberg in the northern Atlantic. Out of the 2200 passengers on board, 1500 died many of these because there were too few lifeboats. Subsequently, more stringent safety rules and iceberg warning systems were adopted. 

Calculation tools of this kind are very useful to the designer or to the overall system analyst (even if they leave the true specialists of the branch rather puzzled), as they allow the study of many cases and for transient times as long as are desired. It has been observed, with reference to the Three MUe Island accident, that if the time length of the calculated transients had been prolonged beyond the intervention time of the safety systems, the adopted thermal-hydraulic codes (RELAP and so on) could have shown the danger of getting to a situation where the pressurizer is substantially full of liquid while the reactor vessel is nearly empty. As it is known, this situation may cause the operators to erroneously think that all of the primary system is full and therefore make them shut off the safety injection systems. In fact, the calculations performed were stopped precisely at the moment of their intervention. 

NSSS Safety System -Safety Injection System with DVI -POSRV -Fluidic Device in Safety Injection Tank - SIS with Direct Vessel Injection - POSRV design - Fluidic Device(FD) Adoption - No change from basic design... 

The system safety planning group either adopts the tasks and products outlined in Chapters 7 and 8 or develops alternatives. This effort should include guidelines for establishing project phases, review points, and levels of review and approval. 

Making Health Care Safer H An Updated Critical Analysis of the Evidence for Patient Safety Practices is the result of a panel of patient safety experts who assessed the evidence behind 41 patient safety strategies and identified 10 strategies that health systems should adopt now. The strategies can help prevent harmfnl events snch as med errors, bedsores, and healthcare-associated infections. Making Health Care Safer II npdates Evidence-based Practice Center report ( 43), which was published in 2001 and provided the first systematic assessment of patient safety practices. 

Most plants now favor software-based safety systems over the older hardware-dominated approach. These systems were adopted piecemeal, with the result that practices vary widely between companies and even between plants within a company. Now, the International Electrotechnical Commission (lEC) has adopted and published a generic standard, lEC 61508, that brings together much of the published material and provides a framework for its coordination [63]. 

The private sector has begun to develop system-safety programs because of the successes of the military and NASA. Leading the way are the nuclear power, refining, and chemical industries. The adoption of system safety in those industries manufacturing consumer products has generated returns in terms of more effective products, fewer accidents, and longer product life. 

The role of the safety professional is to anticipate, identify, and evaluate hazards give advice on the avoidance, elimination, or control of hazards and attain a state for which the risks are judged to be acceptable. To achieve this, they adopt a system-safety concept that includes ... 

The concept of the I C and electrical systems in HSBWR are basically the same as those in ABWR However, the electrical load is much smaller because the recirculation system is eliminated Furthermore, the I C and electrical systems are very simplified, e g the reduction of emergency diesel generator capacity, because passive safety systems are adopted... 

In the absence of a holistic approach to system safety assessment, it is tempting to concentrate safety assessment effort on what we understand or think we understand (such as hardware and software) and to adopt a head in the sand approach to the human factors which are often perceived as too difficult. Humans are often the major causal factor for hazards in safety-related systems (Sandom 2002) and yet human failures often don t receive proportionate attention in safety analyses. On the other hand, human operators also often provide substantial mitigation between... 

The approach adopted here provides an assessment framework based around analysis of low-level functions within the OS and the (high-level) services provided to the SRS, by the OS. We believe that this goes some way towards meeting the above requirements and providing a systematic approach to reaching decisions as to whether an OS could validly be deployed in support of a specific SRS. This approach ensures that the role of assessor for the OS can be independent of, and different in scope from, that of the systems safety assessor. The crux is to ensure that the OS assessment identifies and provides evidence about properties of the services and functions in such a way that this information can be used in the assessment of the application, without the application assessor needing to understand details of the OS (and vice versa). 

Although there were countless seminars and a proliferation of papers on system safety, the generalist in the practice of safety seldom adopted... 

To take Into account the various approaches that have historically been adopted to assess system safety Integrity. The guidelines framework should therefore be particularly useful -... 

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