Where:
Cadj = pollutant concentration adjusted to 7 percent oxygen;
Cmeas = pollutant concentration measured on a dry basis;
(20.9-7) = 20.9 percent oxygen-7 percent oxygen (defined oxygen correction basis);
20.9 = oxygen concentration in air, percent; and
%O2 = oxygen concentration measured on a dry basis, percent.
40 C.F.R. §60.2690