| Meets A.C.S. Specifications |
| Meets Reagent Specifications for testing USP/NF monographs |
| Assay (Na2SO3) (by iodometry) | min. 98.0 % |
| Insoluble Matter | max. 0.005 % |
| Free Acid | Passes Test |
| Titrable Free Base (meq/g) | max. 0.03 |
| Chloride (Cl) | max. 0.02 % |
| Heavy Metals (as Pb) | max. 0.001 % |
| Iron (Fe) | max. 0.001 % |
| For Laboratory, Research or Manufacturing Use |