Test Measured parameter Maximum microbial concentration [CFU/mL] Zahn-Wellens Test (302 B) DOC (0.7 ÷ 3) • 107 SCAS (302 A) DOC (2 ÷ 10) • 107 MITI (II) (302 C) O2 (0.7 ÷ 3) • 106

Table 4: IBTs (adapted by Struijs et al. [38]).