Safety Systems, Impact

HOW DOES A SAFETY SYSTEM IMPACT SAFETY CULTURE (FIGURE 13.1)... 

FIGURE 13.1 How a safety system impacts safety culture. 

Evaluate Effectiveness on the Basis of Outputs and Acceptance Once the system has been implemented on its chosen site, its effectiveness needs to be evaluated at frequent intervals so that corrective action can be taken in the event of problems. The first criterion for success is that the system must generate unique insights into the causes of errors and accidents, which would not otherwise have been apparent. Second, the system must demonstrate a capability to specify remedial strategies that, in the long term, lead to enhanced safety, environmental impact and plant losses. Finally, the system must be owned by the workforce to the extent that its value is accepted and it demonstrates its capability to be self-sustaining. 

There are some aspects of process design in which decisions are based primarily on past experience rather than on quantitative performance models. Problems of this type include the selection of constraction materials, the selection of appropriate models for evaluating the physical properties of homogeneous and heterogeneous mixtures of components, and the selection of safety systems. Advances in expert systems technology and information management will have a profound impact on expressing the solutions to these problems. 

When an accident occurs in a plant, various safety systems come into play to prevent the accident from propagating. These safety systems either fail or succeed. The event tree approach includes the effects of an event initiation followed by the impact of the safety systems. 

Scale-up can also have a significant effect on the basic process control system and safety systems in a reactive process. In particular, a larger process will likely require more temperature sensors at different locations in the process to be able to rapidly detect the onset of out-of-control situations. Consideration should be given to the impact of higher-temperature gradients in plant-scale equipment compared to a laboratory or pilot plant reactor (Hendershot 2002). 

Condensate leakage caused explosion which impacted safety systems and spread incident 167 Fatalities, total facility loss estimated at 1,000,000,000. 

Fortunately, for a couple of reasons, the likelihood of a terrorist attack on a nuclear reactor is quite low. Nuclear reactors operate under tight security and incorporate safety systems. In addition, the extensive shielding around reactors would require large amounts of explosives to create a breach. Even if terrorists could transport large amounts of explosives, they would have to breach a security cordon to reach the reactor. Alternatively, they could commandeer a jumbo jet plane to crash into a reactor or a nuclear pond of used cores, but they would have to breach security measures to do so. Computer modeling indicates that the constraction of most reactors would sustain a 300 mph impact from a commercial aircraft, but not aU scientists agree with these findings (1). 

Effective occupant restraints, safety systems, and protective equipment not only spread impact energy over the strongest body structures but also reduce contact velocity between the body and the impacted surface or striking object. The design of protective systems is aided by an understanding of injury mechanisms, quantification of human tolerance levels and development of numerical relationships between measurable engineering parameter, such as force, acceleration or deformation, and human injury. These relationships are called injury criteria. 

The containment above reactor serves as the additional safety system barrier. Its main purpose is the protection against external effects. Low storage of potential ener in the primary circuit restricts the RI destruction scale to only external impacts. 

Finally, although not directly performance-related, safety monitors are also worth a mention as they provide reassurance to the athlete and coach or supporting team and can enable survival, particularly for disabled athletes and those involved in impact sports, extreme sports and sports in remote locations. The Riddell Insite helmet for American football is an example of a safety system where impact sensors alert the sideline team when a certain threshold has been reached (Riddell, 2014). 

Experience has been gained also in operation of various steam generator designs. Based on this experience, effective automatic SG safety systems have been designed to assure shutdown of failed SA on the stage of small leak (before it grows to large ). Thus, any impact on the reactor plant from failed SG is eliminated. 

The enterprise analyzes and prioritizes potential functional failure modes to define failure effects and identify the need for fault detection and recovery fimctions. Functional reliability models are established to support the analysis of system effectiveness for each operational scenario. Failures, which represent significant safety, performance, or environmental hazards, are modeled to completely understand system impacts. 

The base scenarios are classified by initiating events or safety system availability which may impact on an accident progression. Left hand side of Fig. 2 represents sample database structure of analysis results for a loss of offsite power initiating event which can be applied to the OPR-1000 plant. There are 12 base scenarios depending on the operation status ofplant safety features. The operation status of safety systems are ... 

External hazards play an important role in the safety assessment for nuclear facilities Since they have an impact on the facUity as a whole, they have the potential to cause initiating events (loss-of-coolant accidents or transients) and simultaneously to impair the safety systems necessary to limit the consequences of the initiated events. 

To find acmal causes of an air event and determine capabilities to apply suitable preventive mea-sures/actions, one should define all factors at each stage of the chain of safety , which could have impeded the aircrew actions, and hence, proved conducive to the occurrence of a given air event. Therefore, detailed expert opinions and investigations are required to facilitate gaming information on haz-ards/threats to the system as a whole. The chain of safety allows investigators to find how the following components of the system impacted human errors (Fignre 5) ... 

PIEs may have an impact on safety systems by means of local effects, such as direct mechanical contact or jet impingement, as well as global effects, such as flooding, increases in humidity, increases in temperature, asphyxiant effects and higher radiation levels. These possible effects should be analysed. 

Safety Program Management — The Federal Motor Carrier Safety Regulations (FMCSRs) were not written to take the place of, or become, your safety effort. Compliance, in and of itself, does not ensure safety. The second major tab is really the core of this manual. Here you will learn how to use the FMCSRs as a framework for developing a comprehensive and integrated safety program — a safety system that overlaps all departments, and impacts all employees. 

Applications and uses telephone line splice cases, switches, connectors, housings, improved impact brake and fuel line clips, wheel covers, headlamp bezels and covers, panels, power distribution boxes, cold temperature air bag doors, automotive safety systems, wheel covers, impact fascias, improved impact appliance lids, power tools, panels, and housings. 

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