Documentation, limiting values and tolerances

All data of relevance (instrument types, serial numbers, column data, chromatographic parameters, auxiliary instruments, etc.) need to be listed in the documentation. Likewise, all chromatograms and other reports (detector noise, wavelength registration) are part of the file. The calculations must be traceable. All deviating results must be documented as well. The documentation is dated and signed by hand by the testing person and the customer (e.g. the laboratory head). 

The set-up of the documentation involves a great deal of work. If an instrument test is ordered at the author s company you will get documents which are accepted by all authorities such as the Food and Drug Administration (FDA). 

A delicate point is the determination of allowed deviations of the individual instruments. One possibility, simple at first glance, is to use the specifications of the manufacturers. However, all instruments are becoming older and their test results may get worse. Also, in many cases the instruments could (fortunately) yield much better results than required by everyday analytical work. It is not good advice to set the limits higher than necessary. As an example, the ISO norms 900x do not request specific test methods. Therefore, each laboratory can define its quality requirements itself. It is, however, important that they have been stated and documented. 

For this reason no limiting values are published in this chapter. In the case of cooperation with the author s company, the quality requirements are discussed thoroughly and documented in the individual documentation (Standard Operating Procedure, SOP). 

---