Table 1: Codes for the dual-chemical combinations and their respective dosing factors.

c-PAMa (100 ppm)
−101

Sc
 −1A1Sc1: 1/20A2Sc1: 2/20A3Sc1: 3/20
 0A1Sc2: 1/30A2Sc2: 2/30A3Sc2: 3/30
 1A1Sc3: 1/40A2Sc3: 2/40A3Sc3: 3/40
NS
 −1A1NS1: 1/30A2NS1: 2/30A3NS1: 3/30
 0A1NS2: 1/45A2NS2: 2/45A3NS2: 3/45
 1A1NS3: 1/60A2NS3: 2/60A3NS3: 3/60

c-PAMb (100 ppm)
−101

gp
 −1B1gp1: 1/1B2gp1: 2/1B3gp1: 3/1
 0B1gp2: 1/2B2gp2: 2/2B3gp2: 3/2
 1B1gp3: 1/3B2gp3: 2/3B3gp3: 3/3
NS
 −1B1NS1: 1/4B2NS1: 2/4B3NS1: 3/4
 0B1NS2: 1/8B2NS2: 2/8B3NS2: 3/8
 1B1NS3: 1/12B2NS3: 2/12B3NS3: 3/12

A = c-PAMa, B = c-PAMb; 1 = lower, 2 = middle, and 3 = higher level of 22 factorial design. Ex: A1Sc1: 1/20 means both c-PAMa and Sc under lower level and the concentrations are 100 ppm and 2,000 ppm, respectively.