Catastrophe defined

A third path to catastrophe defines the warning state base speed.v = 2 arm pos.v = 1 where both interventions are again suggested. We choose inhib arm again and therefore add the warning state to flag inhib arm. 

Risk-Based Inspection. Inspection programs developed using risk analysis methods are becoming increasingly popular (15,16) (see Hazard ANALYSIS AND RISK ASSESSMENT). In this approach, the frequency and type of in-service inspection (IS I) is determined by the probabiUstic risk assessment (PRA) of the inspection results. Here, the results might be a false acceptance of a part that will fail as well as the false rejection of a part that will not fail. Whether a plant or a consumer product, false acceptance of a defective part could lead to catastrophic failure and considerable cost. Also, the false rejection of parts may lead to unjustified, and sometimes exorbitant, costs of operation (2). Risk is defined as follows ... 

When the design temperatures are significantly below ambient temperature, the primary threat to tank integrity is failure of the material by britde fracture. The tank design codes usually provide thorough treatment of this topic to prevent catastrophic failure. Additionally, there is the consideration of corrosion allowance, defined as extra thickness added beyond that required for strength. Corrosion allowance is not discussed herein. 

Elastic Behavior. Elastic deformation is defined as the reversible deformation that occurs when a load is appHed. Most ceramics deform in a linear elastic fashion, ie, the amount of reversible deformation is a linear function of the appHed stress up to a certain stress level. If the appHed stress is increased any further the ceramic fractures catastrophically. This is in contrast to most metals which initially deform elastically and then begin to deform plastically. Plastic deformation allows stresses to be dissipated rather than building to the point where bonds break irreversibly. 

With the advent of computerized real-time systems, the distinction between continuous and periodic condition monitoring must be modified. Though technically periodic, a scanning system operating fast enough to protect against catastrophic failure is considered continuous. Most people consider one second or faster scan rates as continuous. A scan rate of one second is defined as monitoring each point once each second. 

Threshold Quantity - As defined in 29 CFR 1910.119, the minimum amount of a toxic, reactive, or flammable chemical judged by OSHA as being capable of causing a catastrophic event. The threshold quantity triggers application of the rule s requirements, tonnes - A metric ton, i.e., 2,200 lb. 

The NPRDS is an industry-wide system for monitoring the performance of selected systems and components at U.S. commercial nuclear power plants. Information in NPRDS is derived from a standardized format input report prepared by U.S. nuclear plant licensees. The plants are as)ced to submit failure reports on catastrophic events and degraded failures within the defined reportable scope reporting of incipient events is optional. Command faults are not reportable unless they malce an entire system unavailable. In addition, the plants are as)ced to file component engineering reports on all components within the selected systems and reportable scope. These reports contain detailed design data, operating characteristics, and performance data on the selected systems and components (over 3000 components, from approximately 30 systems, per unit). The selected systems are primarily safety systems. 

The IEEE Std 500 document is based on a hierarchical structure of component types set down in the manual s table of contents. The preface for each subsection (defined by a component type) provides a tree diagram that clearly shows the way the component classes have been subdivided to determine "data cells". The failure modes for each component class are also hierarchically organized according to failure severity catastrophic, degraded, or incipient. Rates per hour and demand rates (per cycle) are both included, as well as upper and lower bounds. 

To meet this requirement, a company must define an incident in specific terms for their facility. This includes an operational definition that indicates the number of pounds of the substance used in a particular process that would qualify as a catastrophic event . Defining an incident in site-specific terms also includes defining the terms "could reasonably have resulted in . Appendix C of the regulation provides guidelines for clarifying this point. It includes definitions of "near misses in which a catastrophic failure occurred, but a chemical release did not occur. Clear guidelines should be established that provide the employee with a quantifiable means of defining those incidents that require a violation report. 

The second kind of insurance products that stimulate adaptation is based on the availability of capital to cope with catastrophes. These are financial arrangements intended to bring needed capital that will reduce the risk that could derive from future climate-related hazards for those who are most likely to be in peril. These products can be defined as adaptation oriented because they help to build the capacity of nations, communities, and businesses to cope with climate change impacts. 

Suppose that, as our wedding anniversary approaches, our goal is to avoid having to return home to live with mother. Assuming that we are spineless enough that we need to consult an expert system for advice on how this catastrophe can be avoided, the goal is defined as ... 

The New Jersey Department of Environmental Protection uses the TXDS method of consequence analysis to estimate potentially catastrophic quantities of toxic substances, as required by the New Jersey Toxic Catastrophe Prevention Act (TCPA). An acute toxic concentration (ATC) is defined as the concentration of a gas or vapor of a toxic substance that will result in acute health effects in the affected population and 1 fatality out of 20 or less (5% or more) during a 1-hr exposure. ATC values, as proposed by the New Jersey Department of Environmental Protection, are estimated for 103 extraordinarily hazardous substances and are based on the lowest value of one of the following (1) the lowest reported lethal concentration (LCLO) value for animal test data, (2) the median lethal concentration (LC50) value from animal test data multiplied by 0.1, or (3) the IDLH value. 

The EPA Risk Management Plan (RMP) defines a worst-case scenario as the catastrophic release of the entire process inventory in a 10-min period (assumed to be a continuous release). The dispersion calculations must be completed assuming F stability and 1.5 m/s wind speed. As part of the RMP rule, each facility must determine the downwind distance to a toxic endpoint. These results must be reported to the EPA and to the surrounding community. 

There is also a certain amount of statistical information available on the failures of process system components. Arulanantham and Lees (1981) have studied pressure vessel and fired heater failures in process plants such as olefins plants. They define failure as a condition in which a crack, leak or other defect has developed in the equipment to the extent that repair or replacement is required, a definition which includes some of the potentially dangerous as well as all catastrophic failures. The failure rates of equipment are related to some extent to the safety of process items. If a piece of equipment has a long history of failures, it may cause safety problems in the future. Therefore it would be better to consider another equipment instead. It should be remembered that all reliability or failure information does not express safety directly, since all failures are not dangerous and not all accidents are due to failures of equipment. 

In this chapter we will be concerned mainly with the formation of high polymers of isobutene, and with the fundamental studies aimed at the elucidation of this reaction. There is no doubt that many useful hints of fundamental interest are to be found in the patent literature, but in most cases the purity of the reagents and the reaction conditions are so ill defined, that no conclusions can be drawn from findings reported in patents. The ratio of scientifically valuable to dubious information in patents is so small that detailed survey of them, in the hope of discovering sound information, should be a most unrewarding occupation. This is more or less true of all chemical patents, but especially so in this particular field where minute traces of impurities can effect catastrophic changes in the reaction pattern. For this reason attention has been confined to work published in the scientific literature. 

Implement a program to define and record information on reactive incidents that OSHA investigates or requires to be investigated under OSHA regulations. Structure the collected information so that it can be used to measure progress in the prevention of reactive incidents that give rise to catastrophic releases. 

Regardless, the classification system should achieve a specific outcome and add value. To achieve this goal, companies should consider developing a classification scheme that helps establish the proper team composition based on the complexity, nature, and severity of the occurrence. Chapter 7 describes considerations for building a team based on classification of an incident. The chapter defines terms such as minor incidents, limited impact incidents, significant incidents, high-potential incidents (HIPO), and catastrophic incidents. 

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