Assessment of the Content of the Main Components of Breathing Mix. Part I

In quantitative instrumental analysis, measurement results are most often obtained in the form of relative analytical signals, which require in the calibration process1 reference to measurement standards² in order to determine the value of the measured quantity³ with the accuracy and precision needed. The measurement results are influenced by a number of interfering factors that are difficult to define unambiguously and simultaneously⁴ and which shape the magnitude of systematic errors. These are mitigated by carrying out measurements on test samples and reference samples under conditions that are as close to identical as possible, which allows for the determination of appropriate corrections to the measurement results obtained from the conversion of relative analytical signals. The measurement process, which takes such corrections into account, is considered to be under statistical control, i.e. on the assumption that random components are the dominant component of measurement uncertainty.

The articles present a method for estimating measurement uncertainty based on measurement standards, used in instrumental analysis, which is under statistical control of the process. It is illustrated by the determination of the content of the main components of breathing mixtures in diving with the separation of components by gas chromatography using a thermal conductivity detector⁵.