Acceptance sampling

As discussed before, groundwater samples can be collected when a sufficient volume of water has been removed from the well (e.g., three to five well volumes) and groundwater parameters have stabilized. If parameters have not stabilized after five well volumes have been removed, then the well may be sampled (acceptance of sampling following the fifth purge volume is dependent on the study objectives). Table 1 summarizes the criteria used for establishing the stability of groundwater parameters. The time intervals between the parameter measurements depend on the well characteristics and the hydraulic properties of the aquifer and must be sufficiently spaced to provide results representative of aquifer properties. ... 

However, other approaches may be equally valid. For instance, some inter-laboratory assessments utilise samples that have been spiked with a known concentration of an impurity(ies). Thus if the receiving laboratory meets the pre-determined acceptance criterion this constitutes an acceptable transfer. The transfer protocol is pre-approved by both transferring and receiving laboratory(ies) and stipulates all of the details of methodology, samples, acceptance criterion and appropriate method variability. 

The purpose of sample acceptance criteria is to confirm that the run for a test article is suitable for quantification. The corrected peak area of the sample should be within linear range of the assay the baseline should be suitable for integration the corrected peak percentage should be in a reasonable range. Again, for a purity assay, migration time is usually not a critical parameter. 

An interference check standard is a standard solution used to verify an accurate analyte response in the presence of possible interferences from other analytes present in the samples. For methods that have known interference problems arising from the matrix or that are inherent in the method, such as ICP-AES (spectral interference lines) and ICP-MS (isotope combinations with similar masses to analyte), these solutions are used in the batch. The interference check standard must be matrix matched to acid content of the samples. Acceptance criteria are set—for example, the magnitude of uncorrected background and spectral interference must not be greater than a stated value. 

Are surrogate standard recoveries in each sample acceptable ... 

Sample Acceptability a. Matrix Red meat and poultry muscle and Stability... 

Sample Acceptability Refer to Determinative Method, section J.5. and Stability... 

Multivariate Chemical Classification of Rainwater Samples, accepted for publication in Chemometrics and Intelligent Laboratory Systems, 1986. 

Optimally, X-ray crystallography requires single crystals of a few tenths of a millimetre in size, which are not intergrown and which have grown slowly (they are usually of better quality). Neutron experiments generally require larger crystals a decade ago ca. 5mm was considered a standard size, but recent improvement of the technique make considerably smaller samples acceptable (<1 mm ). 

Assuming that the laboratory can deal with the samples, accepting that their charges are 2 per determination plus 1 per sample for sample preparation then this will cost 13104. 

The guidelines established by the Journal of Chromatography B required precision to be within 10% RSD for the high QC samples and within 20% RSD for the low QC sample. Acceptance criteria for accuracy (bias) were not specified therein [12]. 

Each analytical run should include calibration and quality control samples. Acceptance criteria should be defined in SOPs. 

Type of sample Accept Sample size Reject Decision number Total sample... 

These individual values are not always useful, but if we pose the normal QC question of what probability of acceptance is attached to the above example, when the sample acceptance number is say 1 or 2, we can use the addition law, i.e. ... 

Pennsylvania Avenue, N.W., Attn TSCA 13 Coordinator, Chemical Control Division, Washington, DC. The addressee can elect to separate the samples, accept one, sign and submit the post importation certificate for that sample, and reject the other. The addressee remains responsible for the cost of returning or disposing of the rejected sample. ... 

Polar samples acceptable atmospheric pressure ionization (API) methods enable interfacing with reversed phase columns... 

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