http://www.legislation.gov.uk/id/eudr/2010/75/annex/VI

ANNEX VITechnical provisions relating to waste incineration plants and waste co-incineration plants

E_{S} = \frac{{21 – O}_{S}}{{21 – O}_{M}} {× E}_{M}

E_S: calculated emission concentration at the standard percentage oxygen concentration
E_M: measured emission concentration
O_S: standard oxygen concentration
O_M: measured oxygen concentration