ABSTRACT
In accordance with BS EN 61207-1:1994, the error is the difference between the device reading and the real value of the measuring parameter [1]. Indeed, if the real value is equal to
x
and the measured value is equal to
x
, then the absolute error of the measuring device is
Δ
x
=
x
–
x
. In this case the error manifests itself in the units of the physical or chemical measuring parameter. However, it is not always convenient to manifest error in the absolute values because, in reality, the absolute value of the error indicates neither the quality of the measuring instrument nor the quality of the measuring process. In fact, the accuracy of zirconia gas sensors is determined by a combination of internal errors (due to random and systematic effects); fluctuation of external sensitivities such as temperature, presence of moisture, and combustible gases in the measuring environment; and uncertainty of the gas mixtures used to calibrate it. The term
uncertainty
should be used to characterize the inaccuracy of an obtained result, while the term
error
is used to characterize the components of the uncertainty.
