| Inspection item % | First Grade | Result |
| KOH | ≥ 90 | 90 |
| K 2 CO 3 | ≤ 0.5 | 0.4 |
| Chloride (Cl) | ≤ 0.005 | 0.004 |
| Fe | ≤ 0.0005 | 0.0004 |
| Sulfate (SO4) | ≤ 0.005 | 0.004 |
| Nitrate (N) | ≤ 0.0005 | 0.0004 |
| Na | ≤ 0.8 | 0.7 |
| Phosphate (PO4) | ≤ 0.005 | 0.004 |
| Silicate (SiO3) | ≤ 0.01 | 0.01 |
| Al | ≤ 0.002 | 0.001 |
| Ca | ≤ 0.005 | 0.004 |
| Ni | ≤ 0.0005 | 0.0004 |
| Heavy metal (as Pb) | ≤ 0.002 | 0.001 |
