Division 2 Where several measurement instruments of different quality are contributing to measurement results, either of the following methods shall be used for splitting installation-level data on quantities of materials, fuels, measurable heat or electricity to sub-installations:

Determination of the split based on a determination method, such as sub-metering, estimate, correlation, used equally for each sub-installation. Where the sum of the sub-installation data is different from the data determined separately for the installation, a uniform ‘reconciliation factor’ shall be applied for uniform correction to meet the total figure of the installation as follows:

where RecF is the reconciliation factor, DInst is the data value determined for the installation as a whole, and DSI are the data values for the different sub-installations. The data for each sub-installation are then corrected as follows:

If only one sub-installation's data are unknown or of lower quality than the data of other sub-installations, known sub-installation data may be subtracted from the total installation data. This method is preferred only for sub-installations which contribute smaller quantities to the installation's allocation.