| Test item | Unit | Specification | Test datum |
| K2S2O5 | g/100g | ≥97.2 | 97.3 |
| SO2 | g/100g | ≥56.0 | 56.14 |
| K2S2O3 | g/100g | ≦ 0.1 | 0.002 |
| Na | g/100g | ≦ 2 | 0.090 |
| Cl | g/kg | ≦ 0.5 | 0.01 |
| pH-value(10%solution) | – | 3.8-4.8 | 4.4 |
| heavy metal（measured by Pb） | mg/kg | ≦10 | 8 |
| As | mg/kg | ≦ 1 | 0.05 |
| Cu | mg/kg | ≦1 | 0.3 |
| Fe | mg/kg | ≦5 | 3.6 |
| Hg | mg/kg | ≦0.1 | 0.02 |
| Pb | mg/kg | ≦1 | 0.5 |
| Se | mg/kg | ≦1 | 0.1 |
| Zn | mg/kg | ≦ 1 | 0.3 |
