| ITEM | STANDARD |
| Appearance | White deliquescent crystalline powder |
| Assay (Dry Basis) | 99.0-100.5% |
| pH (5% Solution) | 7.5- 9.0 |
| Loss on Drying (150℃, 2h) | =< 1.0% |
| Chlorides (Cl) | =< 0.05% |
| Sulphate (SO4) | =< 0.01% |
| Magnesium (Mg) | =< 0.01% |
| Iron (Fe) | =< 0.001% |
| Lead (Pb) | =< 5 mg/kg |
| Arsenic (As) | =< 3 mg/kg |
| Heavy Metal (as Pb) | =< 10 mg/kg |