Accuracy
The data are not always of the same accuracy as this depends on the method of measurement, the method
of calculation and whether estimates were used. The method and frequency of taking samples and the appli
cation of conversion factors for certain parameters can also result in data with a low degree of accuracy. In
particular, the quantity of the refrigerant is difficult to determine because we use dynamic systems in which
the refrigerants are in both liquid and gaseous phases. The refrigerant losses are determined by the amount
that is used to top up the systems. This is a less accurate method than measuring the losses directly.
Comparability
The comparability of the data is affected by the degree in which estimates are used to determine the
relevant indicators for the achieved results. Comments in the text of chapter 5 indicate where estimates
were used.
At Heineken, work is being carried out continuously to draw up uniform definitions and instructions to be
used for reporting, to improve the accuracy and comparability of the data.