Qualitative Consequence Evaluation

Qualitative consequence evaluation involves defining broad categories, which are based on the general level of injury and damage that could... 

Qualitative frequency evaluation can be used to screen out events that are extremely unlikely to occur (i.e., have such a remote chance of occurring that further evaluation is unnecessary). This method is particularly appropriate for use in conjunction with qualitative consequence evaluation as a means of ranking risks. 

SUMMARY OF FINDINGS. The PSM Rule requires a qualitative evaluation of the consequences of engineering and/or administrative control failures, to show the range of possible safety and health effects on workers and offsite populations. This information can be obtained from the PrHA by selecting those scenarios that cover the range of possible health effects, and then discussing the existing protection (see Section 3.2). It may be necessary to conduct a rudimentary, quantitative consequence evaluation in order to provide the qualitative information required. 

ERA S RMP requires that the order in which PrHAs are conducted be prioritized based on offsite consequences. The qualitative evaluation of safety and health impacts focuses on impacts on public health and environment rather than impacts on employees. The identification of previous incidents as a part of the prevention program PrHA is limited to those with offsite consequences rather than those with catastrophic consequences in the workplace as required by the PSM Rule. Facilities are expected to have fewer incidents to consider under the ERA RMP rule, because some potential incidents will not have offsite impacts. Another ERA requirement, which is not included in the OSHA PSM rule, is that a facility define its management system. Facilities are required to identify the person (by name) or the position responsible for implementing the prevention program. 

What-If/Checklist analysis identifies hazards, possible accidents, qualitatively evaluates tlie consequences and determines the adequacy of safety levels. It is described in CCPS (1 )92 ). 

Consequently, inappropriate (P-6) and appropriate (P-6/S-200) separations yield significantly different results for the degree of polymerization distribution and average values of degree of polymerization (Fig. 16.27). In a first and qualitative evaluation, dp distribution achieved from P-6/S-200 differs significantly in symmetry from the dp distribution of P-6. In particular, differences in separation performance become obvious for high dp components. In a... 

Mechanistic Approaches. Adequate and appropriate river-quality assessment must provide predictive information on the possible consequences of water and land development. This requires an understanding of the relevant cause and effect relationships and suitable data to develop predictive models for basin management. This understanding may be achieved through qualitative, semi-quantitative or quantitative approaches. When quantitative or semi-quantitative methods are not available the qualitative approach must be applied. Qualitative assessments involve knowledge of how basin activities may affect river quality. This requires the use of various descriptive methods. An example of this kind of assessment is laboratory evaluation of the extent to which increases in plant nutrients, temperature or flow may lead to accelerated eutrophication with consequent reduction of water quality. 

Using a tool such as a qualitative risk ranking matrix can be very useful in identifying low-risk buildings. For those events that have potentially major or catastrophic consequences to buildings and their occupants, however, a qualitative risk matrix may not always be an appropriate final evaluation. For events that are potentially major or catastrophic, regardless... 

Site-specific consequence screening for explosion can be performed either qualitatively or quantitatively, depending upon the explosion potential of the materials being handled, as well as processing conditions and other site-specific factors. In performing a consequence screening, it is necessary to select "Evaluation-case" events for consideration. This is defined as follows ... 

Qualitative frequency evaluation involves defining broad categories of event frequency, which can be used to assess the likelihood of occurrence of a specific incident outcome (consequence). These categories cover a full spectmm of frequencies, from those representing events that are likely to those that are highly unlikely. Definitions of likelihood categories vary, but Table 5.4 presents a typical list and definitions. 

Quantitative evaluation of the severity of accident consequences is not required. However, the PrHA team must qualitatively evaluate the range of the possible employee safety and health effects. Such evaluation is generally made by discussing the severity of consequences of each scenario (see Section 4). 

This evaluation may be performed more explicitly by assigning a qualitative term to each scenario. Typical qualitative terms such as "negligible, low, moderate, severe, and catastrophic" represent the order-of-magnitude consequences found in MIL-STD-882C. 

The purpose of a what-if/checklist analysis is to identify hazards, consider the types of accidents that can occur in a process or activity, evaluate in a qualitative manner the consequences of these accidents, and determine whether the safety levels against these potential accident scenarios appear adequate. The what-if/checklist analysis is described in detail in Guidelines for Hazard Evaluation Procedures (CCPS, 1992). 

In general, risk reduction is accomplished by implementing one or more protective layers, which reduce the frequency and/or consequence of the hazard scenario. LOPA provides specific criteria and restrictions for the evaluation of protection layers, eliminating the subjectivity of qualitative methods at substantially less cost than fully quantitative techniques. LOPA is a rational, defensible methodology that allows a rapid, cost-effective means for identifying the protection layers that lower the frequency and/or the consequence of specific hazard scenarios. 

Risk analysis is a term that is applied to a number of analytical techniques used to evaluate the level of hazardous occurrences. Technically, risk analysis is a tool by which the probability and consequences of accidental events are evaluated for hazard implications. These techniques can be either qualitative or quantitative. 

The quantitative evaluation of expected risk from potential incident scenarios. It examines both consequences and frequencies, and how they combine into an overall measure of risk. The CPQRA process is always preceded by a qualitative systematic identification of process hazards. The CPQRA results may be used to make decisions, particularly when mitigation of risk is considered. 

Any chemical reaction, whether involving the main chain or side groups, results in a change of composition of one or more groups and consequently in the IR spectrum. This makes it possible to study oxidation, thermal degradation, cyclization, grafting, and other reactions of polymers [2,4]. Evaluation of both qualitative and quantitative changes, as well as determination of kinetic constants of the reaction, is possible [2]. 

Consequently, with the present knowledge of reductive dehalogenation reactions of Cr and C2-compounds, and considering the quality of the various molecular descriptors, only qualitative, or at most semiquantitative, predictions of the relative reactivities of a confined set of structurally related compounds in a given system are possible. Nevertheless, evaluation of such relative reactivities in different systems may provide important insights into such reactions, which will be demonstrated by the following two examples. These two examples will, however, also illustrate the... 

Whereas no quantitative consequence analysis is required by this legislation, the process hazards analysis must include a qualitative evaluation of the possible effects of failure of controls on employees. Details concerning development and implementation of programs for these subjects are available... 

Finally, a recurring result indicates that crossover is completed within a quite small temperature range, and in some cases is even nonmonotonous. Actually, accounting for the uncertainties necessarily involved in the primary experimental data and in data evaluation, the sharpness of crossover may be debated in some cases. However, at least at the qualitative level, sharper crossover than observed with nonionic fluids seems to be established. Such a sharp crossover has severe consequences for theoretical interpretations. 

A comparison of a data set PARCC parameters to the corresponding acceptance criteria enables us to evaluate all of the quantitative and qualitative aspects of total error. Because every component of total error affects at least one of the PARCC parameters, as shown in Table 1.1, we should make every effort to minimize their cumulative degrading influence on the PARCC parameters and consequently, on data quality. 

The intensities of the integrated signals may be evaluated on the basis of well-characterized standards. Consequently ISS provides qualitative and quantitative information on the composition of the surface. Noble gas ions that penetrate the first layers of the surface are backscattered as neutrals, and thus may not pass the energy analyzer. As a consequence, only ions backscattered at the first atomic layer are detected and the method is sampling the outmost atomic layer. A soft sputter process by noble gas ions yields an ISS depth profile with atomic depth resolution. Therefore ISS has been applied to the study of very thin oxide films, as e.g. of passivated Fe/Cr alloys. This method may be applied in addition to XPS due to its high depth resolution. 

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