India Opens Consultation on Revised Manganese Sulphate Standard
The Bureau of Indian Standards (BIS), through its Inorganic Chemicals Technical Committee (CHD 1), has issued a Wide Circulation Draft of the Indian Standard titled “Manganese Sulphate, Monohydrate — Specification (First Revision)”. Prepared under document number CHD 1 (33261) WC and dated 29 January 2026, the draft proposes revisions to the existing standard. Stakeholders and interested parties are invited to submit their comments and suggestions until 30 March 2026.
Scope and Key Changes
Originally published in 1983, the revised standard updates the specification for manganese sulphate, a chemical widely used in animal feed, paints, varnishes, electroplating, textiles, ceramics, paper, and dry battery manufacturing. The revision introduces instrumental test methods as alternative procedures for determining the levels of iron, lead, arsenic, calcium, and chloride. It also incorporates a reference clause and updates packing and marking requirements. In addition, test results must be rounded off in accordance with IS 2:2022, with the number of significant figures matching the specified values.
Grades and Specification Requirements
The draft distinguishes between two grades of the material.
- Grade 1 (pure grade): the direct final product.
- Grade 2 (technical grade): a by-product of production operations.
The draft specification also clarifies packing and marking requirements. The material shall be supplied in polyethylene-laminated jute bags or in any other agreed packaging. Each package must be clearly and permanently marked with the name and grade of the material, the name of the manufacturer and, if applicable, the recognized trademark, the gross and net weight, the date of packing, and the lot or batch number.
The requirements for manganese sulphate, monohydrate, are specified in the table below.
| Characteristic | Requirements | |
| Grade 1 | Grade 2 | |
| Manganese sulphate (as MnSO4.H2O), % by mass | 97.0 to 98.0 | 83.0 to 85.0 |
| Manganese (as Mn), % by mass | 31.60 to 31.95 | 27.01 to 27.70 |
| Insoluble matter, % by mass | 0.2 | 0.5 |
| Chloride (as Cl), % by mass | 0.03 | 0.03 |
| Magnesium and alkali metals (as SO4), % by mass | 0.6 | – |
| Calcium (as Ca), % by mass | 0.2 | – |
| Zinc (as Zn), % by mass | 0.05 | 0.05 |
| Iron (as Fe), % by mass | 0.005 | 0.08 |
| Heavy metals (as Pb), % by mass | 0.002 | 0.05 |
| Arsenic (as as), % by mass | 0.0005 | – |
| Oxygen absorbed from permanganate (as O), % by mass | 0.0008 | – |
| Ammonium sulphate [as (NH4)2SO4], % by mass | – | 15 |
