Factor I Analysis: Kinetic Factors (RFI Score)
| Baseline Conditions = 20 °C for 1 day; assign a value of 10 | |
|---|---|
| Effect of Contact Temperaturea (Temperature aspect) | |
| If the temperature of contact is … | Multiply the baseline condition value by … |
| <5 °C | 0.01 |
| 5 °C | 0.1 |
| 20 °C | 1 (this is the baseline condition value) |
| 40 °C | 10 |
| 60 °C | 100 |
| Effect of Contact Durationb (Duration aspect) | |
|---|---|
| If the duration of contact is … . | Multiply the baseline condition value by … |
| Less than 1 day | (duration in hours/24 h)1/2 |
| 1 day | 1 (this is the baseline condition value) |
| Greater than 1 day | (duration in days/1 day)1/2 |
| RFI Score = (Baseline value of 10) × (Temperature aspect, Tf) × (Duration aspect, tf) | |
| Representative RFI Scores | ||
|---|---|---|
| Temperature (°C) | Duration (days) | RFI Score |
| 20 | 1 | 10 (baseline) |
| 20 | 30 | 10 × 1 × (30)1/2 = 55 |
| 20 | 180 | 10 × 1 × (180)1/2 = 134 |
| 40 | 1 | 10 × 10 × (1)1/2 = 100 |
| 40 | 30 | 10 × 10 × (30)1/2 = 548 |
| 60 | 1 | 10 × 100 × (1)1/2 = 1000 |
| 5 | 1 | 10 × 0.1 × (1)1/2 = 1 |
| 5 | 365 | 10 × 0.1 × (365)1/2 = 19 |
| -20 | 365 | 10 × 0.01 × (365)1/2 = 1.9 |
| -20 | 730 | 10 × 0.01 × (730)1/2 = 2.7 |
| Typical Range in RFI Scores: 1–1000 | ||