Section 503.25 - Operational standards-pathogens and vector attraction reduction(a)Pathogens-sewage sludge (other than domestic septage). The Class A pathogens requirements in § 503.32(a) or one of the Class B pathogen requirements in § 503.32 (b)(2) through (b)(4) shall be met when sewage sludge is placed on an active sewage sludge unit, unless the vector attraction reduction requirement in § 503.33(b)(11) is met.(b)Vector attraction reduction-sewage sludge (other than domestic septage). One of the vector attraction reduction requirements in § 503.33 (b)(1) through (b)(11) shall be met when sewage sludge is placed on an active sewage sludge unit.(c)Vector attraction reduction-domestic septage. One of the vector attraction reduction requirement in § 503.33 (b)(9) through (b)(12) shall be met when domestic septage is placed on an active sewage sludge unit.