| Parameters | Exhaust method | Modified exhaust method |
| pH | 4.5 - 5.0 | 4.5 - 5.0 |
| Concentration | 0.3% - 2% | 10% |
| Time | 20 to 30 minutes | 2 hours |
| Temperature | 40˚C | 40˚C |
| Drying | Dry at room temperature | Dry at room temperature |