KENYA STANDARD                      KS 2220    2020             
 
 
 
 
 
 
 
 
 
 
  
Magnesium sulphate fertilizer — 
Specification  
 
 
 
 
 
 
 
 
        
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
     Draft   Standard March  2020                                    Third   edition  
        
 
 
 
 
  
ii     
 
 
  
TECHNICAL COMMITTEE  REPRESENTATION  
 
The foll owing organizations were represented on the Technical Committee:  
 
Kenya Agricultural and livestock Research Organization (KALRO)  
Government chemist  
Mea Ltd   
Amiran (K) Ltd  
Chemagro Ltd.  
Yara East Africa  
Kenya Tea Development Agency.  
Kenya Plant Health In spectorate Services (KEPHIS)  
Ministry of Agriculture, livestock and fisheries  
Osho Chemicals Ltd  
Elgon chemicals   Ltd  
Toyota Tshuso   Fertilizers Africa  
University of Nairobi -Department of plant science and crop protection  
OCP Africa  
ICL Fertilizers  
Lach lan(K) Ltd  
Wanda Agriculture  
National Potato Council of Kenya  
Kenya Industrial Research and Development   Institute  
Top serve East Africa  
Elgon(K) Ltd  
Kenya flower council  
Kenya Chemical society  
SGS(K) Ltd  
BASF Chemicals  
Twiga Chemicals  
Sanergy   Ltd  
SABIC    Ltd   
SOCAA  
Samsung C& T  
 
 
 
REVISION OF KENYA STANDARDS  
 
In order to keep abreast of progress in industry, Kenya Standards shall be regularly reviewed. Suggestions 
for improvements to published standards, addressed to the Managing Director, Kenya Bureau  of Standards, 
are welcome.  
 
 
 
© Kenya Bureau of standards, 2020  
 
Copyright:  Users are reminded that by virtue of Section 6 of the Copyright Act, Cap. 130 of the Laws of Kenya, copyright subsists in all 
Kenya Standards and except as provided under Section  7 of this Act, no Kenya Standard may be reproduced, stored in a retrieval 
system in any form or transmitted by any means without prior permission in writing from the Managing Director.   
KEBS  2020 — All rights reserved   iii  
KENYA    STANDARD     KS 2220 : 2020                     
           
 
 
 
 
 
 
 
 
 
 
 
 
Magnesium S ulphate fertilizer  — 
Specification  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
iv     
 
KENYA BUREAU OF STANDARDS (KEBS)  
 
Head Office:  P.O. Box 54974, Nairobi -00200, Tel.: (+254 020) 605490, 602350, Fax: (+254 020) 604031  
E-Mail: info@kebs.org,  Web:http:// www.kebs.org   
 
Coast Region     Lake Region          Rift Valley Region  
P.O. Box 99376, Mombasa -80100   P.O. Box 2949, Kisumu -40100        P.O. Box 2138, Nakuru -20100Tel.: 
(+254 041) 229563, 230939/40                Tel.: (+254 057) 23549, 22396        Tel.: (+2 54 051) 210553, 
210555Fax: (+254 041) 229448    Fax: (+254 057) 2 027814 Foreword  
 
 
 
Foreword  
 
This   Kenya standard has been  prepared by the Technical Committee on Fertilizers and 
soil conditioners  under the guidance of the standards project committee and it  is in 
accordance with the procedures of the  Kenya  bureau of standards.  
 
During   the revision of the standard the minimum nutrient content for Sulfate   has been 
reviewed. Due to the nature of the product , which is hygroscopic , the moisture requirement 
has been removed.  
 
 
During the review of the standard reference has been made to the following document  
 
 
Indian fertilizer   specifications - 2018  
 
 
 
 
 
 
 
 
 
 
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           KENYA STANDARD                          KS 2220   :  2020            
 
 
Magnesium S ulphat e fertilizer — Specification  
 
1.0 Scope  
 
This Kenya Standard specifies the requirements, methods of sampling and tests for 
magnesium  sulphate fertilizer.  
 
 
2.0. Definitions and terms  
The terms and abbreviations used in this standard are in accordance with the explanations 
contained in this document: ISO 8157:2015 ; fertilizers  and soil conditioners: vocabulary  
 
3.0 Requirements  
 
3.1 Description   
 
The material shall consist essentially of magnesium sulphate, and shall be in the fo rm of 
free flowing crystals,  powder or granules   It shall be free from visible foreign matter.  
 
3.2 Physical  
 
The particle size shall be such that not less than 90 % by mass shall be in the particle size 
range of 1 mm to 4 mm.  
 
3.3 Chemical  
The material shall comply with the requirement s set out in table 1 when tested in 
accordance with the methods specified in the last column of the table.  
 
SL.NO  Characteristic  requirement  Test method  
i) Water soluble 
magnesium 
content (as 
mgo)% by 
weight , min 16.0 AOAC  
ii) Sulphate  content  
as S O4 (% b y 
weight)  min 30. AOAC  
 
  
A. 
 
2.6 Heavy metal contaminants   
 
The heavy metal contaminants, if present, shall not exceed the limits stipulated in Table 2.  
 
 
  
 
 Table 2 — Heavy metal contaminants limits  
 
SL NO  Parameter  Limits in 
ppm Test method  
i) Arsenic, As, max.  20.0 AOAC  
ii) Cadmium, Cd, max.  7.0 AOAC  
iii) Mercury, Hg, max.  0.1 AOAC  
iv) Selenium, Se, max.  1.0 AOAC  
v) Lead, Pb, max.  30.0 AOAC  
 
 
3 Packaging and marking  /labelling  
 
 
3.1 Packaging   
 
3.1.1 The fertilizer shall be packaged in materials that ensures  the product integrity  and 
quality against   physical  damage , chemical and moisture contamination.  
 
3.1’2. the fill of the package shall comply with the weight and measures act CAP 513 of the 
laws of Kenya  
 
3.1.3 The disposal of used package and  condemned fertilizer shall comply with EMCA 1999 
no.8 of the disposal of solids and liquid wastes  
 
 
3.2 Marking / labelling  
The following information shall be clearl y and indelibly marked on each package or container.          
 
i. Name, address and physical locati on of manufacturer/packer/importer;  
ii. name of the fertilizer, i.e.  “Magnesium sulphate  fertilizer  ‘     
iii.  Guaranteed  percentage by mass of the  water soluble  magnesium and sulphur 
content  
iv. date of manufacture,  
v.  expiry date  
   vi.      batch/lot number  
   Vii         the net weight of the fertilizer in the package; in metric units  
  Viii         Storage  and Handling instructions  
  ix             Instructions  for use  
   x           d isposal instructions  
   xi. Country  of origin;  
 
4 Certificate of analysis  
  
 3 Each c onsignment shall be accompanied by a certificate of analysis.  
 
4 Sampling  
 
Sampling   shall be carried as   outlined in the ISO standards listed below  
 
ISO 8633 -Solid fertilizers -- Simple sampling method for small lots ISO 8634 - Solid fertilizers -
- Samplin g plan for the evaluation of a large delivery