Factor II Analysis, Thermodynamic “Leaching Power” (RFII Score)
| Baseline Conditions = Aqueous with a pH between 5 and 8; assign a value of 1 | |
|---|---|
| Effect of pHa (pH Aspect) | |
| If the pH of contacting solution is … | The value of the pH aspect is … |
| 1 or lower | 243 |
| 2 | 81 |
| 3 | 27 |
| 4 | 9 |
| 5 | 3 |
| 6 | 1 (this is the baseline condition value) |
| 7 | 1 (this is the baseline condition value) |
| 8 | 3 |
| 9 | 9 |
| 10 | 27 |
| 11 | 81 |
| 12 or higher | 243 |
| Effect of Polarityb (Polarity Aspect) | |
|---|---|
| If the % ethanol in the contact solution is … . | The value of the polarity aspect is … |
| 0 | 1 (this is the baseline condition) |
| 10 | 2 |
| 20 | 4 |
| 30 | 8 |
| 40 | 70 |
| 50 | 450 |
| 60 | 1300 |
| 70 or greater | 7600 |
| RFII Score for pHc = (Baseline value of 1) x (pH aspect); Typical range = 1 to 243 | |
| RFII Score for polarityc = (Baseline value of 1) x (Polarity aspect); typical range = 1 to 7600 | |
↵Notes: a Based on an analysis of the effect of pH on the “leaching power” of simulating solvents; see reference 20.
↵b Based on an analysis of the effect of ethanol content on the “leaching power” of simulating solvents; see reference 21.
↵c The pH and polarity effects are calculated separately and there is no “composite” effect, taking into account both pH and polarity. If both pH and polarity are relevant, then use the RFII score that is the highest (pH versus polarity).