When cathode solution volume is 3 cm3 (greater than 2.75 cm3), DigiCORA uses ηA = 1 according to equation E-3-10 of GAW Report 268.
When cathode solution volume is 2.5 cm3 (less than 2.75 cm3), DigiCORA applies a pressure-based correction to the absorption efficiency according to equations E-3-11-A and E-3-11-B of GAW Report 268.