Ammonium Phosphate Sulphate (16-20-0) fortified with Magnesium
A fortified fertiliser specified under the Fertiliser Control Order, 1985 (Schedule I, Part A, 1(h), item 33). Key notified values: Total ammoniacal nitrogen 16.0 max; Available Phosphorus 20.0 min; Water soluble Phosphorus 17.0 min. Added by S.O. 4477(E) of 22 Sep 2022.
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Specification
As notified in the Order, line by line. Values are per cent by weight unless the line says otherwise.
How to read this table
- Minimum means the product must contain at least this much; maximum means not more than this (moisture, impurities and heavy metals have a maximum).
- Per cent by weight means grams in every 100 g of product: 0.5 per cent zinc is 5 g of zinc in every kg.
- P₂O₅ and K₂O: phosphorus and potassium are declared as their oxides. To get the element, multiply P₂O₅ by 0.436 and K₂O by 0.830.
- Tolerance: a lab result may fall slightly short of the notified value before the sample is called non-standard; the limits are in Schedule I, Part B.
- S.O. … (E) is the number of the Gazette notification that made a change; “in force” (w.e.f., with effect from) is the date it started to apply.
| Parameter | Notified value | |
|---|---|---|
| (i) | Moisture per cent. by weight, maximum | 1.0 |
| (ii) | Total ammoniacal nitrogen per cent. by weight, maximum | 16.0 |
| (iii) | Available Phosphorus (as P₂O₅) per cent. by weight, minimum | 20.0 |
| (iv) | Water soluble Phosphorus (as P₂O₅) per cent. by weight, minimum | 17.0 |
| (v) | Sulphate Sulphur (as S) per cent. by weight, maximum | 13.0 |
| (vi) | Magnesium (as Mg) per cent. by weight, minimum | 0.6 |
| (vii) | Particle Size - minimum 90% of the material shall be retained between 4 mm and 1 mm IS sieve. |
Applies to all fortified fertilisers (S.O. 2345(E), 29 May 2023): It includes all such fertiliser of standard prescribed in Schedule I and is fortified with maximum two micronutrients of the range specified in para (i) of sub-clause (q) of clause 2.
Tolerance: how far a sample may fall short of a declared value is set in Schedule I, Part B; see the tolerance limits.
Test method (Schedule II, Part B): method 28: Customised and fortified fertilisers.
Check a lab report
Compare the results of a lab test with this specification, line by line, including the tolerance allowed in Part B. Enter each result as on the report (per cent by weight unless the line says otherwise). A guide only: the report of a notified laboratory decides whether a sample is standard.
| Parameter | Notified | Lab result | Result |
|---|---|---|---|
| (i) Moisture | 1.0 maxtolerance 0.3 units | ||
| (iii) Available Phosphorus | 20.0 mintolerance 0.5 units | ||
| (iv) Water soluble Phosphorus | 17.0 mintolerance 0.5 units | ||
| (vi) Magnesium | 0.6 mintolerance 0.06 units | ||
| (vii) Particle size | 90% of the material mintolerance 7 units |
Not checked here: Total ammoniacal nitrogen, Sulphate Sulphur.
Notification history
- 22 Sep 2022S.O. 4477(E): entry inserted
Before you make, label or buy it
- Manufacturers and importers: each declared value on the label must meet the limit above; samples are tested by the notified method.
- Dealers and farmers: check that the product name and declared contents on the pack match this specification, and keep the bill with the batch number.
- Doses are not part of this specification: follow the label and local agricultural advice.
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Consolidated by NanoKheti from the Fertiliser (Inorganic, Organic or Mixed) (Control) Order, 1985, as amended up to the Ninth Amendment Order, 2026 (S.O. 4045(E), 22 Jul 2026), for reference. The Gazette text is authoritative; this page is not legal advice. Check the notification before labelling, licensing or buying. Checked for later changes on 20 October 2026.