| Assay: | 98.0-103.0% (NH4)2HC6H5O7 |
| MAXIMUM ALLOWABLE | |
| Insoluble matter: | 0.005% |
| Residue after ignition: | 0.01% |
| Chloride (Cl): | 0.001% |
| Heavy metals (as Pb): | 5 ppm |
| Iron (Fe): | 0.001% |
| Oxalate (C2O4): | Passes test |
| Phosphate (PO4): | 5 ppm |
| Sulfur compounds ( as SO4): | 0.005% |