Specification limit, lower

The performance index which accounts for process centering and defined as the minimum of the upper or lower specification limit minus the average value divided by 3o. 

Figure 4.22. Correlation of assay values for components A and B, for three dosage levels of A, with 10 samples per group. The comer symbols indicate the 10% specification limits for each component. For manual injection (left panel) only relative standard deviations of 1-2% are found, but no correlation. Automatic injection (right panel) has a lower intrinsic relative standard deviation, but the data are smeared out along the proportionality line because no internal standard was used to correct for variability of the injected volume. The proportionality line does not go through the comers of the specification box because component B is either somewhat overdosed (2.4%). analytical bias, or because an interference results in too high area readings for B. The...

Figure 4.26. Shelf-life calculation for active components A and B in a cream see data file CREAM.dat. The horizontals are at the j = 90 (specification limit at t = shelflife) resp. y = 95% (release limit) levels. The linear regression line is extrapolated until the lower 90%-confidence limit for Kfl = a + h x intersects the SLs the integer value of the real intersection point is used. The intercept is at 104.3%.

Ermer and coworkers [15, 38], recommended that the acceptance criteria for the standard deviation of the determinations should be lower than 1/6 of the specification range (upper specification limit, USL minus lower specification limit, LSL), or calculated using the following equation ... 

Compared with conventional impurities measurements, trace analyses caimot be expected to achieve the same linearity and precision values. This is due to the lower signal-to-noise ratios inevitable at low levels. Hence, while the same approaches can be used, greater latitude will be necessary in the acceptance criteria. What must be demonstrated is that the data is statistically valid to show that the levels of toxic analytes are below their specification limits. 

The points where L(x) intersects the acceptable lower specification limit 8 can be obtained by finding the roots of the following equation 8 - L(x) = 0. It should be pointed out that this equation can also be written in the form... 

Since the minimum of all the expiration dating periods is the shortest shelf life among all batches, this estimate will provide a 95% confidence that the strength of the drug product will remain above the acceptable lower specification limit. 

Add a volume of standard lead solution containing each of the following three levels of lead to samples of the drug substance the content equal to the expected specification limit and those higher and lower than the... 

Adjust the volume of lead standard solution to be the same as that for preparation of the control solution. Prepare at least seven or eight levels of lower-concentration test solutions from the specification limit value of 0.1 to 0.2 ppm (single replicate). 

Values for acceptance criteria, RSD, upper and lower specification limits, including significant figures... 

It is now clear that electrochemical measurements can often have significant advantages over the classical spectroscopic approaches. Amperometry can be more specific therefore, lower detection limits are often feasible. Because electrochemical detectors do not require optical carriers, they can be much less expensive than UV absorption or fluorescence detectors. This is especially true when one considers that electrochemical detectors are inherently tunable without the need for such things as monochrometers or filters. On the other hand, there can be significant problems with reliability, and, more often than not, there is a lack of acceptance by chemists weaned on Beer s law. Amperometric methods in biochemistry are just beginning to be commercialized, and it is now almost certain that they will come into widespread use. 

Establishing specification limits from the test data derived for a given parameter. Based on the data collected and using statistical techniques, determine the extremes of acceptable hardness (high and low) that would provide 95% assurance that the friability, disintegration, and dissolution specifications would be met (upper and lower control/ release limits). 

Process Capability Indices Also known as process capability ratios, these provide a measure of w hether an in-control process is meeting its product specifications. Suppose that a quality variable x must have a volume between an upper specification limit (USL) and a lower specification limit (LSL) in order for product to satisfy customer requirements. The capability index Cp is defined as... 

Distillates are lower cuts from the atmospheric crude distillation column (Fig. 18.10) thus, these refinery streams may have high sulfur concentrations due to the feedstock that is processed. Newer product specifications limit sulfur concentrations in consumer products, especially diesel. Consequently, distillate streams must be... 

Specification limit. Note that the reporting level can never be lower than the limit of quantitation (LOQ) of the method. However, during early-phase validation for drug products, if authentic degradation products are not available, then low amounts of API are added (LOQ to 120% specification limit of largest impurity) to the placebo and the recovery experiment is performed. 

Based on this, the Kiosk Configurators determined that the kiosk should display the refinancing terms within two minutes (120 seconds) for all users. In essence, the team set an upper specification limit (USL) at 120 seconds. There is no lower specification limit (LSL) because an instantaneous response is still acceptable (although very unlikely). 

Specification limits can be one-sided or two-sided. For two-sided specifications, you combine the capability of the lower specification limit (LSI) and the upper specification limit (USL) to derive an overall sigma level. Extensions to unstable processes, two-sided specifications, and distributions that are not normally distributed require additional analysis. 

These limits are obtained from customer input, regulatory requirements, or design functional requirements. Upper specification limit (USL) refers to the maximum allowable value for the parameter, whereas lower specification limit (LSL) indicates the minimum allowable value. 

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