PUBLIC REVIEW DRAFT DRAFT UGANDA STANDARD  
      DUS DEAS 93-1 
Second  Edition 
     2019- mm- dd 
 
 Reference number  
DUS DEAS 93 -1: 2019 
© UNBS 2019 
   
Preservation of raw hides and skins — Code of practice — Part 
1: Stack Salting 
 
 PUBLIC REVIEW DRAFTDUS DEAS 93-1: 2019 
ii                © UNBS  2019 - All rights reserved 
 Compliance with this standard does not, of itself confer immunity from legal obligations 
A Uganda Standard does not purport to include all necessary provisions of a contract. Users are 
responsible for its correct application  
© UNBS 2019 
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilised in any 
form or by any means, electronic or mechanical, including photocopying and microfilm, without prior written 
permission from UNBS. 
Requests for permission to reproduce this document should be addressed to 
The Executive Director 
Uganda National Bureau of Standards 
P.O. Box 6329 
Kampala 
Uganda 
Tel: +256 417 333 250/1/2 
Fax: +256 414 286 123 
E-mail: info@unbs.go.ug  
Web: www.unbs.go.ug  
 PUBLIC REVIEW DRAFTDUS DEAS 93-1 : 2019 
© UNBS  2019 - All rights reserved                iii National foreword 
Uganda National Bureau of Standards (UNBS) is a parastatal under the Ministry of Trade, Industry and 
Cooperatives established under Cap 327, of the Laws of Uganda, as amended.  UNBS is mandated to co-
ordinate the elaboration of standards and is  
(a) a member of International Organisation for Standardisation (ISO) and  
(b) a contact point for the WHO/FAO Codex Alimentarius Commission on Food Standards, and  
(c) the National Enquiry Point on TBT Agreement of the World Trade Organisation (WTO). 
The work of preparing Uganda Standards is carried out through Technical Committees. A Technical 
Committee is established to deliberate on standards in a given field or area and consists of representatives of 
consumers, traders, academicians, manufacturers, government and other stakeholders. 
Draft Uganda Standards adopted by the Technical Committee are widely circulated to stakeholders and the 
general public for comments. The committee reviews the comments before recommending the draft standards 
for approval and declaration as Uganda Standards by the National Standards Council.  
This Draft Uganda Standard, DUS DEAS 93-1: 2019,  Preservation of raw hides and skins — Code of practice 
— Part 1 : Stack Salting , is identical with and has been reproduced from an International Standard, DEAS 93-
1: 2019, Preservation of raw hides and skins — Code of practice — Part 1 : Stack Salting , and is being 
proposed for adoption as a Uganda Standard. 
The committee responsible for this document is Technical Committee UNBS/TC 7, Textiles, leather, paper 
and related products , Subcommittee SC 2 , Leather and related products.  
This standard cancels and replaces the first edition (US EAS 93-1:2000) which has been technically revised. 
Wherever the words, “ East African Standard " appear, they should be replaced by "Uganda Standard."    DEAS 93-1 : 2019  
ICS 59.140  
  
© EAC 20169                                                                                                                             Second Edition 2019  
 DRAFT EAST AFRICAN STANDARD 
Preservation of raw hides and skins — Code of practice Part 1 : Stack 
Salting 
EAST AFRICAN COMMUNITY  DEA S 93-1: 2019 
ii © EAC  2019 – All rights reserved  
 Copyright notice 
This EAC document is copyright-protected by EAC. While the reproduction of this document by 
participants in the EAC standards development process is permitted without prior permission from 
EAC, neither this document nor any extract from it may be reproduced, stored or transmitted in any 
form for any other purpose without prior written permission from EAC. 
Requests for permission to reproduce this document for the purpose of selling it should be addressed 
as shown below or to EAC’s member body in the country of the requester:  
© East African Community 2016 — All rights reserved 
East African Community  
P.O.Box 1096 
Arusha 
Tanzania 
Tel: 255 27 2504253/8 
Fax: 255 27 2504481/2504255 
E-mail: eac@eachq.org 
       Web: www.eac-quality.net 
Reproduction for sales purposes may be subject to royalty payments or a licensing agreement. 
Violators may be p rosecuted.                                                                                                                                 DEAS 93-1: 2019 
© EAC 2019 – All rights reserved  iii 
 Foreword 
Development of the East African Standards has been necessitated by the need for harmonizing requirements 
governing quality of products and services in the East African Community. It is envisaged that through 
harmonized standardization, trade barriers that are encountered when goods and services are exchanged 
within the Community will be removed.  
In order to achieve this objective, the Community established an East African Standards Committee 
mandated to develop and issue East African Standards.  
The Committee is composed of representatives of the National Standards Bodies in Partner States, together with the 
representatives from the private sectors and consumer organizations. Draft East African Standards are circulated to 
stakeholders through the National Standards Bodies in the Partner States. The comments received are discussed and 
incorporated before finalization of standards, in accordance with the procedures of the Community. 
East African Standards are subject to review, to keep pace with technological advances. Users of the East African 
Standards are therefore expected to ensure that they always have the latest versions of the standards they are 
implementing .  
DEAS 93-1, was prepared by Technical Committee EASC/TC/063                                                
 DRAFT EAST AFRICAN STANDARD                       DEAS 93-1: 201 9 
 
© EAC 2016 – All rights reserved  1 
 1. SCOPE 
This Draft East African Standard shall apply to raw hides and skins to be preserved by salting and intended 
for tanning. 
 2.  NORMATIVE REFERENCES 
The following referenced documents are indispensable for the application of this document. For dated 
references, only the edition cited applies. For undated references, the latest edition of the referenced 
document (including any amendments) applies. 
ISO 4045, Leather  — Chemical tests — Determination of pH  
ISO 4044, Leather  — Chemical tests — Preparation of chemical test sample 
ISO 2821, Leather - Raw hides of cattle and horses - Preservation by stack salting 
ISO 2820, Leather - Raw hides of cattle and horses - Method of trim 
 
ISO 4684, Leather — Chemical tests — Determination of volatile matter 
 
3. TERMS AND DEFINITIONS 
For the purposes of this standard, the following terms and definitions and those given in ISO 2821 shall 
apply. 
3.1  
salting 
preservation method by application of salt mixture or soaking in the brine solution to dehydrate fresh hides 
and skins in order to prevent the development of putrefaction. 
3.2 
stacking 
piling with a sloping top 
3.3 
fleshing 
removal of excess meat and fat still adhering to the hides and skins 
3.4 
trimming 
removal of unwanted parts and give the hide and skin shape 
3.5 
hide 
 outer covering of a large animal including bovine, camel and equine 
3.6 
skin 
 outer covering of small animal including ovine, caprine, reptiles, fishes, bird and porcine  
2 © EAC  2019 – All rights reserved  
 3.7 
tanning 
a process of conversion of raw hides and skins from putrescible material to non-putrescible material that is 
resistance to deterioration by bacteria and chemical 
SALTING 
4.1 METHOD 
4.1.1 Fresh hides and skins shall be preserved by salting in one of the following methods: 
a) By spreading a salt mixture; or 
b) By soaking in brine solution. 
4.1.2 The salting method consists of dehydrating fresh hides and skins sufficiently in order to prevent the 
development of bacterial putrefaction, and stacking them in appropriate premises by piling them one on top 
of the other. 
4.1.3 The proper application of a salt mixture or soaking in brine solution prevents the possible 
development of defects mentioned in the note 1. below. 
4.2 PROCEDURE A — BY SPREADING SALT MIXTURE . 
4.2.1 General requirement  
Before spreading salt mixture, hides and skins shall be cleaned in the manner described below and then 
cooled. 
a) The fresh and dirty hides and skins shall be laid on a clean, solid and sloping surface. 
b) Both sides of the hide and skins shall be carefully washed, fleshed, trimmed and cleaned with cold 
water. 
c) Such cleaned hides or skins shall be adequately drained. 
4.2.2 Salting 
Cleaned hides or skins (4.2.1) shall be treated with a salt mixture for stacking in the following manner: 
a) For salting hides or calfskins, a mixture of granulated industrial salt shall be applied. A mixture may for 
example consist of 100 kg of salt plus 2 kg sodium-solico-fluoride, plus 2.5 kg of sodium carbonate. 
b) The granulated industrial salt shall contain at least 96% sodium chloride with no ad-mixture of ferrous 
salts. 
c) For calfskins, goatskins, sheep skins, granulated industrial salt shall at least contain 96 % sodium chloride 
with no admixture of ferrous salts, in addition to other additives (4.2.2 a) above. 
d) No recovered salt, originating from brushing of hides or calfskins, shall be used. 
e) For hides, salt crystals which will pass through a screen with a mesh of between 1.25 mm and 3.15 mm 
and for calf skins, goatskins hair-sheep skins a screen with a mesh of between 0.4 mm and 0.1 mm shall 
be used.  
© EAC 2019 – All rights reserved  3 
 f) A quantity of salt mixture of at least 40 per cent of the mass of fresh hides or skins shall be used. 
g) Not later than 5 hours after flaying, a hide or skins shall be laid with its flesh side up on a smooth clean 
and solid surface and the salt mixture shall be spread evenly over the entire surface of the hide or skin. 
4.2.3 Stacking  
Salted hides, calfskins, goatskins, hair-sheep skins shall be stacked in the following manner: 
a) They shall be stacked with their flesh side up by spreading one top of the other. 
b) For hides and calfskins, the height shall not exceed 1.5 m. 
c) For goatskins and sheep skins, the stack shall not exceed 1 m. 
d) For draining any liquid the stack shall have small slope to the sides in order to avoid the formation of 
cavities or hollows in the centre in which the liquids can accumulate; if some hides are very large in size, 
then their edges shall be spread with salt and folded inside. 
4.2.4 Stacking premises  
Such hides, calfskins, goatskins, sheep skins shall be stacked in rooms which are cool, well ventilated and not 
humid. Theses premises shall have slopping tops so as to avoid drained liquids accumulating within the 
stacked hides or skins 
4.2.5 Stacking period  
Stacked hides and skins shall be kept in stack for a period of at least 15 days. That is, they shall be kept in 
stack for 7 days, after which, they shall be turned over and more fresh salt added and stack ed again for 
another 8 days.  
4.2.6  Moisture content of hides and skins shall be reduced to 40-50% according to ISO 4684; method of 
moisture content determination.  
4.2.7 Dry salting  
Repeat the procedure in 4.2.2, 3.2.3, and 4.2.4 above, then expose the hides and skins in a shade for at least 
5 days (the moisture content drops to 17 –20 %)  
4.3 PROCEDURE B — BY SOAKING IN BRINE SOLUTION . 
4.3.1 General requirement  
 Before soaking in brine solution, hides and calfskin shall be cleaned according to 4.2.1 and cooled.  
4.3.2 Brining 
Not later than 5 hours after flaying, cleaned hides or calfskins shall be soaked in brine solution for stacking in 
the following manner: 
a) A brine solution in the proportion of one to three by mass of salt to water shall be prepared in vats or 
drums. 
b) The density of such a solution shall be 24 Be (Baume degree) which corresponds to a relative density of 
1.2.  
4 © EAC  2019 – All rights reserved  
 c)  A quantity of salt, which is at least 25 per cent of the mass of the fresh hides or calfskins shall be used in 
solution. 
d) The vat or drum shall be loaded with hides or calf skins provided that the solution shall be recharged 
with salt amounting to 12 per cent of the mass of hides or calf skins when loading following every new 
lot. 
e) Hides or calfskins in load shall be stirred for 15 minutes at an interval of 1 hour for the total duration of 
soaking which shall not exceed 24 hours. 
f) Such hides or calf skins shall be made to drain for not more than 1 hour. 
4.3.3 Stacking 
a) Salted hides or calfskins shall be stacked with their flesh side up by spreading one top of the other. 
b) During the stacking process, a quantity of salt mixture [(indicated in 4.2.2 a)] of at least 2/3 of the mass 
of each hide or calfskin shall be sprinkled on the flesh side of each hide or calfskin. 
4.3.4 Stacking premises  
Salted hides or calfskins shall be stacked in cold rooms as specified in 4.2.4. 
4.3.5 Stacking period 
Stacked hides or calfskins shall be kept in stack for period of at least 15 days or when the moisture content 
reduces to 40%-50% of moisture content when determined by ISO 4684. 
4.3.6 Disposal of dehydrated waste water and used salt 
The used salt and used water after washing hides and skins shall be disposed in accordance with the existing 
national laws and regulations.  
NOTE 1 Origin and nature of salting process defects 
Salting process defects shall be classified according to origin into the following two categories. 
a) Defects of microbial origin such as red spots, purple spots and heating. This is as a result of use of 
contaminated salts 
b) Defects of chemical origin such as pitting on the flesh, pitting on the grain and round spots. This is as a 
result of using fine salt to preserve the hides and skins 
NOTE 2 After spreading granulated industrial salts to hides and skins recommended fungicides/bactericides shall be added also 
4.4. Weighing and packaging 
After the stalking period is over or when the moisture content in the hides or calf skins has reduced to 40%-
50%; the hides and skins shall be weighed and packaged in the following manner: 
4.4.1 Remove the excess salt adhering to hides and skins using mechanical methods such as de-salting 
machine, mechanical shaking or any other appropriate method 
4.4.2. Weigh the hides and skins and/or grade appropriately 
4.4.3 Pack the wet salted or dry salted hides or skins appropriately 
  
© EAC 2019 – All rights reserved  5 
  
 DEAS 93-1: 2019   
 
© EAC 2019 – All rights reserved