Only one "above span" calibration is needed per 24-hour period.
Where:
Cks = Kiln stack concentration (ppmvd, mg/dscm, ng/dscm, depending on pollutant. Each corrected to 7% O2.)
Qab = Alkali bypass flow rate (volume/hr)
Cab = Alkali bypass concentration (ppmvd, mg/dscm, ng/dscm, depending on pollutant. Each corrected to 7% O2.)
Qcm = In-line coal mill flow rate (volume/hr)
Ccm = In-line coal mill concentration (ppmvd, mg/dscm, ng/dscm, depending on pollutant. Each corrected to 7% O2.)
Qks = Kiln stack flow rate (volume/hr)
40 C.F.R. §60.2145