Contributing causes

Fault Tree Construction. Eault tree constmction begins at the TOP event and proceeds, level by level, until all fault events have been developed to their basic contributing causes (BASIC events). The analyst begins with the TOP event and, for the next level, determines the immediate. 

However, in the case of a root cause analysis system, a much more comprehensive evaluation of the structure of the accident is required. This is necessary to unravel the often complex chain of events and contributing causes that led to the accident occurring. A number of techniques are available to describe complex accidents. Some of these, such as STEP (Sequential Timed Event Plotting) involve the use of charting methods to track the ways in which process and human events combine to give rise to accidents. CCPS (1992d) describes many of these techniques. A case study involving a hydrocarbon leak is used to illustrate the STEP technique in Chapter 7 of this book. The STEP method and related techniques will be described in Section 6.8.3. 

Event An occurrence involving equipment performance or human action, or an occurrence external to the system that causes system upset. In this book, an event is associated with an incident either as the cause or a contributing cause of the incident or as a response to the initiating event. 

J. Rotary drilling inside casing. Setting the casing with improper tension after cementing is one of the greatest contributing causes of such failures. 

A further example is the effect of tube failure resulting from longterm overheating. Here it is likely that the principle contributing causes are a combination of deposit formation and stresses resulting from mechanical operation of the boiler in excess of design limits. To minimize or eliminate the risks of deposits and the subsequent effects they produce within the boiler, control again requires a twofold approach ... 

Renal Effects. Hemorrhage of the medullary layer of the kidneys was observed in an early report of three fatal cases of acute oral poisoning with endosulfan (Terziev et al. 1974). More recent studies have reported acute renal failure after ingestion of endosulfan as a major contributing cause of death in two individuals in both cases, postmortem examination showed extensive tubular necrosis (Blanco-Coronado et al. 1992 Lo et al. 1995). Neither case discussed the possible mechanism of endosulfan-induced acute renal failure, but in one case, the authors of the report indicate that the renal lesions may relate to sepsis and shock (Blanco-Coronado et al. 1992). Ingested doses were not determined in any of these cases, and it is not totally clear that the effects observed at autopsy were a direct result of endosulfan exposure, although based on results from acute animal studies, it seems likely. 

Determine whether ethanol is a contributing causative factor. If so, reinforce counseling on the need for abstinence and provide appropriate resources to maintain abstinence (e.g., professional counseling, alcoholics anonymous). 

Review medical and laboratory data to rule out contributing causes of anxiety. 

Electronic interactions with the formation of bonding molecular orbitals (orbital energy) and the electrostatic attraction between the nuclei of atoms and electrons. These two contributions cause the bonding forces of covalent bonds. 

An occurrence involving process, equipment, or human performance either internal or external to a system that causes system upset. In terms of accidents, an event is either a cause or a contributing cause of a "near miss" or accident, or a response to the accident initiating event. 

For instance, a flat tire on an automobile is caused by two possible events. In one case the flat is due to driving over debris on the road, such as a nail. The other possible cause is tire failure. The flat tire is identified as the top event. The two contributing causes are either basic or intermediate events. The basic events are events that cannot be defined further, and intermediate events are events that can. For this example, driving over the road debris is a basic event because no further definition is possible. The tire failure is an intermediate event because it results from either a defective tire or a worn tire. 

The CSB Morton investigation showed that inadequate evaluation and communication of reactive hazards was one important factor in the root and contributing causes of the incident (USCSB, 2000). During the course of the investigation, stakeholders raised concerns and requested further investigation into reactive hazards-particularly in light of similar incidents since 1995. 

Environmental concerns have been raised in recent years dealing with greenhouse gases produced from the transportation industry. A contributing cause of these emissions is the combustion of fossil fuels such as diesel, gasoline and oil. A strong enviromnental initiative has pushed for the development of alternative fuels such as ethanol and biodiesel in pure and blended forms (Demirbas, 2008). 

A causal factor, also known as a critical factor or contributing cause, is a major unplanned, unintended contributor to the incident (a negative occurrence or undesirable condition), that if eliminated would have either prevented the occurrence, or reduced its severity or frequency. 

Each company s management style and safety systems have strengths and weaknesses. These strengths and weakness tend to influence the types and severity of incidents that might occur. An analysis of incident investigation findings in terms of causal factors, immediate causes, contributing causes,... 

Did the investigation go beyond the immediate or obvious causes and discover contributing causes ... 

Contributing Cause—Factors that facilitate the occurrence of an incident such as physical conditions and management practices. (Also known... 

Kanter et al. reported an increase concentration of the corticosteroid binding globulin (CBG) (Kanter et al. 2001). Most cortisol is bound to CBG, and is biologically inactive. A greater concentration of CBG is consistent with low levels of measurable free cortisol, and provides a putative explanation for how cortisol levels could be measurably low even though other aspects of HPA axis functioning do not seem hypoactive. However, the extent to which CBG levels are a contributing cause of low cortisol requires further examination. 

Using X-ray spectrometry, De la Fuente et al. (1999) measured the thermal dependence of the a and c lattice parameters in a Er32/Lu 10)40 superlattice. Again, strong single-ion CEF contributions, originating from the Er/Lu interfaces, were observed in the volume and tetragonal distortions. Their analysis reveals also important contributions caused by epitaxial misfit. 

The work of Pliny includes many subjects related to the chemical knowledge and industries of his time. But Pliny evidently had very little knowledge himself on such subjects and his accounts taken from other writers are frequently lacking in accuracy. Whether this inaccuracy was due to imperfect interpretation of his authorities, or to the fact that the earlier writers were themselves but imperfectly informed upon the subjects treated, it is not possible to say, though the latter is in all probability at least a contributing cause. It follows that many of the descriptions of technical operations as described leave much room for conjecture as to important details. 

So far, speculations which attribute the observed upfield shifts of the NMR signals of 1 to a ring current of the cr-electrons199 (in line with the idea of cr-aromaticity8) have not been refuted. However, a less spectacular rationalization of the NMR chemical shifts in terms of local anisotropy contributions caused by the unique electron distribution of 1 (see Section IV) may also be possible200. 

For CVD processes at atmospheric or reduced pressure, the reactants are usually used in low concentration in H2 or some inert carrier gas. Therefore, volume changes due to the change in the number of moles between reactants and products are negligible. In addition, in CVD processes, unlike in combustion systems, energy contributions caused by heats of reaction are... 

In general, the present results indicate an nonspecific inflammatory reaction in allergy. The expression of the proteins analyzed, at least in their soluble form, may change more as an epiphenomenon of allergy than contribute causatively to the sensitization or effector process. Although their implication in plasma remains unclear, their concentrations may serve as markers for the evaluation of the accompanying inflammation of an allergic disorder. 

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