Establish Performance Criteria

Laboratories using these methods for regulatory purposes are required to operate a formal quality control program. The minimum requirements of the program consist of an initial demonstration of laboratory capability and an ongoing analysis of spiked samples to evaluate and document data quality. The laboratory must maintain records to document the quality of data that is generated. Ongoing data quality checks are compared with established performance criteria to determine whether or not the results of analyses meet the demonstrated performance characteristics of the method. When results of spike sample analyses indicate atypical method performance, a quality control check standard must be analyzed to confirm that the measurements were performed in an in-control mode of operation. 

ST46 Steed, L. and Plant, D. (1988). Use of immunochemistry survey data to establish performance criteria. Clin. Chem. 34, 1247, Abstr. 460. 

In the early applications of chemicals, the methods used for disposal were, in general, performed without consideration of the environmental impact. However, as the volumes of chemicals increased and the consequences of such practices became apparent it was necessary to develop non-polluting methods for the disposal of all chemicals, including solvents. New approaches were required which not only would benefit the environment but also the user, the chemical industry and society as a whole. Sensible legislation is the key driver to achieve a balance between use and impact minimisation. Sustainable development is achieved by establishing performance criteria, cooperation, commitment and by auditing compliance. 

As part of its QA programme, a measurement facility may establish performance criteria to be applied to the analysis of spiked samples, i.e. samples for whieh the radionuclide content is known beforehand. Performance criteria should be well defined limits on the acceptability of the measurement results, as functions of the radionuclide content in the sample versus the MDA of the method. For example, an acceptable result for the analysis of Pu in faeces may be a measured value that lies within the range of 0.75 to 1.5 times the true value, when the true value is at least five times the MDA of the method. Similarly, an acceptable result for the direct measurement of Am in the lungs of a phantom could be a measured value within a range of 0.75 to 1.5 times the tme value, when the true value is ten times the MDA of the method [44]. 

On November 24, 1981, 15 months before the Salem 1 ATWS event, the NRC invited comments on three proposed ATWS rules. Each of the three alternatives had the objective of reducing risk from ATWS and each featured a different approach to achieve that objective. One alternative, the Staff Rule would have resolved ATWS by establishing performance criteria. For example, there would be analyses to verify that Service Level C of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code would not be exceeded, fuel integrity would be maintained, there would be no excessive radioactivity release, the containment would not fail, and long-term shutdown and cooling would be assured. The second alternative, the Hendrie Rule, while using much of the same information... 

The selection of cluster number, which is generally not known beforehand, represents the primary performance criterion. Optimization of performance therefore requires trial-and-error adjustment of the number of clusters. Once the cluster number is established, the neural network structure is used as a way to determine the linear discriminant for interpretation. In effect, the RBFN makes use of known transformed features space defined in terms of prototypes of similar patterns as a result of applying /c-means clustering. 

The performance criterion needed to demonstrate that the above functional requirement is met is that pressure in the SCBs must be maintained negative with respect to the Zone 2A canyon. Design-basis accidents, operational events, and external events that could affect the SCBs are identified and analyzed in Section 3.4. The passive confinement function of the SCBs is continuously demonstrated by monitoring the presence of a pressure differential across the SCB boundary (see the discussion on the use of differential pressure instrumentation for verifying confinement bam er integrity in Section 4.4.1.4). A minimum detectable negative pressure differential of 0.76 mm (0.03 in) WG between Zone 1 (the SCBs) and the Zone 2A canyon establishes the physical Integrity of the SCB confinement boundary. 

The liner coating was performed and hydraulic tests showed no more leakage. The Russian Regulatory Authority established a criterion of maximum fluence of 10 n/cm (E >0,5 MeV) for the coating material. 

Optimization techniques are procedures to make something better. Some criteria must be established to determine whether something is better. The single criterion that determines the best among a number of alternatives is referred to as the performance index or the objective function. Economically, this is the expected profit for a plant design. It may be expressed as the net present value of the project. 

For purposes of our discussion here, we will primarily focus on the single-stage system, which is the simplest. The approaches presented here are appropriate for use in any of these screening systems, although establishment of activity criteria becomes more complicated in successive screens. Clearly, the use of multistage screens presents an opportunity to obtain increased benefits from the use of earlier (lower-order) screening data to modify subsequent screen performance and the activity criterion. 

The evaluation of dose-response relationships is a critical component of hazard characterization (OECD, 1989 ECETOC, 1992 US , 1997a IPCS, 1999). Evidence for a dose-response relationship is an important criterion in establishing a toxic reproductive effect. It includes the evaluation of data from both human and laboratory animal studies. Because quantitative data on human dose-response relationships are infrequently available, the dose-response evaluation is usually based on the assessment of data from tests performed using laboratory animals. However, if data are available in humans with a sufficient range of doses, dose-response relationships in humans can also be evaluated. 

Further, the validation of a model needs the definition of the criterion for establishing that a model has been validated. How well should a model predict effects precisely, and what are the bounds between which one calls a model (sufficiently) valid It also needs the definition of the context against which a model is to be considered valid. For example, validation of the SSD model has generally been based on whether the so-called hazardous concentration for 5% of the species (HC5) is a concentration that is conservative (sufficiently protective) compared to the no-effect concentration in multispecies mesocosm or field tests. In that sense, the model has performed well for both aquatic and terrestrial systems (e.g., Emans et al. 1993 Okkerman et al. 1993 Posthuma et al. 1998 Versteeg et al. 1999 van den Brink... 

In the final analysis, processing time is the main criterion of batch-still design. To achieve optimal cost-effective performance requires a large number of trial calculations, such that the best combination of equilibrium stages, reflux ratio, batch size, and batch-processing time can be established. It is extremely difficult to successfully carry out such a procedure by hand calculation. 

One of the most important quality characteristics of advanced oxidation processes is their ability to reduce the toxicity of an industrial wastewater and to enhance its biodegradability (see Chapter 7.1.5). This criterion can be established by several standardized procedures using different test organisms ranging from microbes to intact animals (cf Tab. 5-1). An easy to perform variant is the bioluminescence assay that uses the inhibition of the bioluminescence intensity of the test organism Vibrio fischeri in the presence of toxic substrates. This is a bioassay used worldwide for the evaluation of toxicity data of individual chemicals or of industrial wastewaters (Froehner et al, 2000, DIN, 1991). Commercial systems are... 

Selection of the correct conveyor for a specific bulk material in a specific situation is complicated by the large number of interrelated factors that must be considered. First, the alternatives among basic types must be weighed, and then the correct model and size must be chosen. Workability is the first criterion, but the degree of performance perfection that can be afforded must be established. 

After the definition of the three hardware elements previously described, one has to establish the software elements intervention criterion, performance measures, type of disturbances and simulation conditions. 

Determine the standards (thresholds) for each criterion. These can reflect universal standards established for the institution s clinical program or expectations of an individual clinical pharmacist. The standards establish departmental expectations regarding the extent to which the individual performs each criterion. The expectations should be objective and expressed clearly. Some sites may decide not to use standards however, they should be cautioned that objective evaluation may be difficult without standards. 

A feedstock specification or product specification provides the data that give adequate control of feedstock behavior in a refinery or product quality. Thus a specification offers the luxury of predictability of feedstock behavior in a refinery or predictability of product quahty (therefore, product behavior) relative to market demand. Ultimately, feedstock behavior and/or product quality is judged by an assessment of performance. And it is performance that is the ultimate criterion of quality. It is therefore necessary to determine those properties, the values of which can be established precisely and relatively simply by inspection tests in a control laboratory, that correlate closely with the important performance properties. 

---