DEAS 135:2020  
ICS 77.140.65 
 
 
 
 
 
 
 
 
 
DRAFT EAST AFRICAN STANDARD  
 
 
Steel wire and Steel wire products for fencing — Specification 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
EAST AFRICAN COMMUNITY  
 
 
 
 
 
 
 
 
 
 
 
© EAC 2020 Second Edition 2020 
 
 
 
  
 
 DEAS 135:2020 
 
 
 
 
 
Contents  Page 
 
 
Foreword  ............................................................................................................................................................ iv  
1 Scope ...................................................................................................................................................... 1  
2 General requirements  ........................................................................................................................... 1  
2.1 Wire diameter and length  ..................................................................................................................... 1 
2.2 Wire physical properties  ...................................................................................................................... 2 
2.2.1 Tensile strength  .................................................................................................................................... 2 
2.2.2 Nominal diameters and tolerances  ..................................................................................................... 3 
2.2.3 Wrapping test for mild and annealed steel wire  ................................................................................ 3 
2.3 Galvanizing  ............................................................................................................................................ 3 
2.3.1 Diameter of wire  .................................................................................................................................... 3 
2.3.2 Purity of coating  .................................................................................................................................... 3 
2.3.3 Weight of coating  .................................................................................................................................. 3 
2.3.4 Uniformity of coating  ............................................................................................................................ 4 
2.3.5 Adhesion of coating  .............................................................................................................................. 5  
3 Specific requirements for galvanized barbed wire  ............................................................................ 5  
3.1 Line and point wire  ............................................................................................................................... 5 
3.2 Line and point wire preferred diameters  ............................................................................................ 5 
3.3 Finish ...................................................................................................................................................... 5 
3.4 Barbed wire formation  .......................................................................................................................... 6 
3.4.1 Continuous Twist  .................................................................................................................................. 6 
3.4.2 Reverse Twist  ........................................................................................................................................ 6 
3.4.3 Other twists  ........................................................................................................................................... 6 
3.4.4 Joints  ...................................................................................................................................................... 6 
3.4.5 Packed rolls weight  ............................................................................................................................... 6  
4 Requirements for galvanized wire netting  .......................................................................................... 6  
4.1 Preferred wire diameters, mess sizes and width of netting  ............................................................. 6 
4.2 Tolerances  ............................................................................................................................................. 8 
4.3 Nominal lengths  .................................................................................................................................... 8  
5 Specification for chain link fencing  .................................................................................................... 8  
5.1 Type of wire  ........................................................................................................................................... 8 
5.2 Preferred wire diameters, mesh sizes and width  ............................................................................... 9 
5.2.1 Diameter  ................................................................................................................................................. 9 
5.2.2 Plastics thickness  ................................................................................................................................. 9 
5.2.3 Mesh sizes and diameter  ...................................................................................................................... 9 
5.3 Requirements of plastics coated wire  .............................................................................................. 10 
5.4 Tolerances  ........................................................................................................................................... 11 
5.5 Nominal length  .................................................................................................................................... 11  
Annex A (normative) Test methods for weight and uniformity of zinc coating  ........................................ 12  
A.1 Determination of weight of coating  ................................................................................................... 12 
A.2 Gravimetric method  ............................................................................................................................ 12 
A.2.1 Reagents  .............................................................................................................................................. 12 
A.2.2 Test piece  ............................................................................................................................................. 12 
A.2.3 Stripping the zinc  ................................................................................................................................ 12 
A.2.4 Calculation  ........................................................................................................................................... 13 
A.3 Gas volumetric method  ...................................................................................................................... 13 
A.3.1 Explanation  .......................................................................................................................................... 13 
A.3.2 Reagents  .............................................................................................................................................. 13 
A.3.3 Apparatus ............................................................................................................................................. 13 
A.3.4 Test pieces  ........................................................................................................................................... 14 
A.3.5 Procedure ............................................................................................................................................. 15 
 
© EAC 1999 – All rights reserved ii 
  
 
 DEAS 135:2020 
 
A.3.6 Calculation  ........................................................................................................................................... 16  
A.3.7 Correction for temperature and barometric pressure ...................................................................... 17 
A.4 Test for uniformity of coating —'Preece' Dip method  ...................................................................... 17 
A.4.1 Reagents  .............................................................................................................................................. 17 
A.4.2 Apparatus  ............................................................................................................................................ 17 
A.4.3 Test pieces  .......................................................................................................................................... 18 
A.4.4 Temperature  ........................................................................................................................................ 20 
A.4.5 Procedure  ............................................................................................................................................ 20 
A.4.6 Examination ......................................................................................................................................... 20 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
© EAC 2020 – All rights reserved iii 
  
 
 DEAS 135:2020 
 
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. 
 
 
 
 
 
 
 
 
 
© East African Community 2020 – All rights reserved*  
East African Community  
P.O. Box 1096  
Arusha  
Tanzania  
Tel: 255 27 2504253/8  
Fax: 255 27 2504255  
E-mail: eac@eachq.org  
Web: www.eachq.org  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
* © 2020 EAC — All rights of exploitation of any form and by any means reserved worldwide for EAC Partner 
States’ NSBs 
 
 
 
 
 
 
© EAC 2020 – All rights reserved iv 
  
 
  
EAST AFRICAN STANDARD                                              DEAS 135:2020  
 
 
 
 
 
Steel wire and steel wire products for fencing — Specification 
 
 
1 Scope 
 
This draft East African Standard specifies requirements, sampling and test methods for steel wires 
and wire products used for fencing purposes. 
 
2 Normative references 
ISO 16120, Non-alloy steel wire rod for conversion to wire -- Part 4: Specific requirements for wire rod for 
special applications 
ISO 7900, Steel wire and wire products for fences — Zinc- and zinc-alloy-coated steel barbed wire  
ISO 6892-1, Metallic materials — Tensile testing — Part 1: Method of test at room temperature  
ISO 6892-2, Metallic materials — Tensile testing — Part 2: Method of test at elevated temperature  
ISO 8458-1, Steel wire for mechanical springs — Part 1: General requirements  
 
3 Terms and definitions 
3.1  
barbed wire 
steel fencing wire constructed with sharp edges or points arranged at intervals along the strands. 
3.2 
galvanized wire 
wire to which a coating of zinc has been applied to the surface as a protection against corrosion 
3.3 
coating 
application of zinc to the surface of wire to prevent environmental deterioration 
3.4 
fencing 
exercising barrier, railing, or other upright structure of wire enclosing an area of ground to prevent or 
control access or escape 
3.5 
line wire 
wire of specified diameter of which the barbed wire is made 
3.6  
point wire 
wire of specified diameter of which the barbs are made 
  
 
 3.7 
wire netting 
application of woven wire so as to produce hexagonal openings of uniform size 
3.8 
chain link fencing 
fence of heavy steel wire woven to form a diamond 
3.9 
mesh 
net made from wire, thread, or plastic 
4.0 
twist 
Combined wire bent in opposite directions so that they are turned away from each other used for 
fencing 
 
4 General requirements  
 
4.1 Wire diameter, length and mass per meter run  
Wires shall be designated in terms of nominal diameter sizes. The diameter shall refer to finished 
wire. Nominal diameters, nominal lengths per 1 kg and mass per metre run shall be as given in Table 
1. 
 
Table 1 — Nominal diameter, nominal length per 1 kg and mass per metre run 
 
Nominal 
diameter 
(mm) ± 2.5 %  Length for 1 kg (m)  Mass per metre run (g/m)  
Minimum 
-5% Nominal Maximum 
+5% Minimum 
-5% Nominal Maximum 
+5% 
0.60 427.85 450.4 472.89 2.11 2.2 2.33 
0.75 273.83 288.2 302.65 3.30 3.5 3.64 
0.80 240.67 253.3 266.00 3.75 3.9 4.14 
0.90 190.16 200.2 210.17 4.75 5.0 5.25 
1.00 154.03 162.1 170.24 5.86 6.2 6.48 
1.25 98.58 103.8 108.95 9.16 9.6 10.12 
1.40 78.59 82.7 86.86 11.48 12.1 12.69 
1.60 60.17 63.3 66.50 15.00 15.8 16.58 
1.80 47.54 50.0 52.54 18.98 20.0 20.98 
2.00 38.51 40.5 42.56 23.44 24.7 25.90 
2.25 30.43 32.0 33.63 29.66 31.2 32.79 
2.50 24.64 25.9 27.24 36.62 38.5 40.48 
2.65 21.93 23.1 24.24 41.15 43.3 45.48 
3.00 17.11 18.0 18.92 52.73 55.5 58.29 
3.15 15.52 16.3 17.16 58.14 61.2 64.26 
3.55 12.22 12.9 13.51 73.84 77.7 81.62 
3.75 10.95 11.5 12.11 82.40 86.7 91.07 
4.00 9.63 10.1 10.64 93.75 98.7 103.62 
4.50 7.61 8.0 8.41 118.65 124.9 131.14 
5.00 6.16 6.5 6.81 146.48 154.2 161.90 
 
 
 
 
© EAC 2020 – All rights reserved 1  
 
.  
 
 DEAS 135:2020 
 
4.2 Wire physical properties 
 
4.2.1  Tensile strength   
Wire shall be drawn from steel according to the tensile strength required.  
4.2.1.1   Drawn mild steel wire   
a) For wires up to and including 2.0 mm, the tensile strength shall be not less than 550 MPa. 
 
b) For wires above 2.0 mm up to and including 3.55 mm, the minimum tensile strength shall 
be 450 MPa. 
 
c) For wires above 3.55 mm, tensile strength shall be not less than 400 MPa. 
 
4.2.1.2 Low tensile wire  
 
All Low tensile wire  shall have a minimum tensile strength of 350 MPa. 
 
4.2.1.3 High tensile wire 
 
a) All wires of all sizes shall have a tensile strength of 900 MPa - 1 300 MPa. 
 
b) Wires of other tensile strengths may be made by agreement between the purchaser and 
the manufacturer. 
 
4.2.2 Nominal diameters and tolerances 
 
Nominal diameters shall be as given in Table 1. All wires shall be subjected to a tolerance of 2.5 % 
nominal wire diameter. 
 
4.2.3 Wrapping test for mild and annealed steel wire 
 
The wire shall not fracture or show any sign of failure after being closely wrapp ed round a wire rod 
of the same diameter for a minimum of six turns. 
 
      Flaking off of the zinc coating in this test shall not be considered as a defect. 
 
4.3 Galvanizing 
 
Galvanized wire shall meet the following requirements: 
 
      4.3.1 The method of coating shall be hot-dip galvanizing. 
 
4.3.2 Diameter of wire 
 
For the purpose of this standard, only wire of circular section of diameters  0.6 mm to 5 mm is 
included. Coating shall be continuous and free from lumps, black spots, and inclusions. 
 
4.3.3 Purity of coating 
 
Metallic zinc used in the preparation of the coating bath shall have purity of not less than 'Zn grade 
98'. 
  
© EAC 2020 – All rights reserved 2
 
.  
 
 DEAS 135:2020 
 
4.3.4 Weight of coating 
 
When determined in accordance with Annex A, the weight of coating shall be not less than that given 
in Table 2 for the appropriate wire; if the test piece has been taken from a fabricated product then the 
minimum weight of coating shall be reduced by 5 %. 
 
4.3.5 Uniformity of coating 
 
When tested in standard copper sulfate solution by the procedure given in Clause A.3 the wire shall 
not show any bright adherent copper deposit after the specified number of dips shown in Table 2. 
 
If the test piece, has been taken from a fabricated product then the specified dips shall be reduced by 
one half-minute dip. 
 
      Table 2 — Minimum weight of coating and number of dips  
 
 
4.3.6 Adhesion of coating 
 
4.3.6.1 For wires of 5 mm or less the adhesion of the zinc shall be tested by wrapping the wire,  at 
least six close turns, round a cylindrical mandrel. Large wires shall be bent through an angle of at 
least 90° round the mandrel. The ratio of mandrel diameter to wire diameter (d) shall be as follows: 
 
a) For wires up to and including 4 mm, the mandrel diameter shall be four times the nominal 
diameter of wire. 
 
b) For wires of over 4 mm diameter, the mandrel shall be five times the nominal diameter of the 
wire. 
 
4.3.6.2 The zinc shall remain firmly adherent to the steel and shall not crack or flake to such an  extent 
that any flake of zinc can be removed by bare hand. 
 
Scratching the surface with fingernails or other objects is not included. 
 
 
© EAC 2020 – All rights reserved 3
 Nominal 
diameter 
of 
coated 
wire Heavy Medium  Commercial  
Weight 
of 
Coating Number of dips  Weight 
of 
Coating Number of dips  Weight 
of 
Coating Number 
of dips 
mm g/m2 1 min 1/2 min g/m2 1 min 1/2 min g/m2 1 min 
0.6 105 1 - 90 - - 14 no test 
0.75 120 1 - 100 1 - 16 no test 
0.8 136 1 1 120 1 1 18 no test 
0.9 150 1 1 140 1 1 25 no test 
1.0 170 2 - 150 1 1 27 no test 
1.25 200 2 - 170 2 - 34 1 
1.4 215 2 - 180 2 - 40 1 
1.6 230 2 - 200 2 - 50 1 
1.8 235 2 1 210 2 - 56 1 
2.0 240 3 - 215 2 - 69 1 
2.5 260 3 - 230 2 1 72 1 
2.65 270 3 1 235 2 1 78 1 
3.0 275 3 1 240 3 - 80 1 
3.15 280 3 1 250 3 - 85 1 
3.55 290 3 1 260 3 - 90 1 
4.0 300 3 1 270 3 - 100 1 
5.0 300 3 1 270 3 - 100 1 
0.6 105 1 - 90 - - 14 no test 
0.75 120 1 - 100 1 - 16 no test 
0.8 136 1 1 120 1 1 18 no test  
 
 DEAS 135:2020 
 
5 Specific requirements for Hot-dip galvanized barbed wire 
 
5.1 Line and point wire 
 
The line and point wire, which the barbed wire is made from, shall comply with the requirements of 
Clause 2 of this standard. 
 
5.2 Line and point wire preferred diameters 
 
The preferred line wire and point wire diameters shall be as given in Table 3. 
 
Table 3 — Preferred nominal wire diameter  
 
Wire type  Steel type  Nominal wire diameter  
 
(mm)    
    
 
Line High tensile  1.4 – 2.0 
 
Low Tensile  1.6, 2.0, 2.5    
    
 
Point High tensile 1.4 – 1.8 
 
Low Tensile  1.6, 2.0, 2.5   
    
 
 
5.3 Finish 
      The wire shall be galvanized in accordance with the requirements of 4.3. 
  
5.4 Barbed wire formation 
 
5.4.1 Continuous twist 
 
The barbs shall be wrapped around two line wires once and around a single strand once, making, in 
all, two turns round the line wires. 
 
The barbs shall be wrapped around a line wire by a method, which prevents slipping to expose the 
four barbs approximately 90° apart in a plane at right angles to the line wire. The points of the barb 
shall have a length of  12 ± 2 mm and shall be sharp and cut at an angle not greater than 35° to the 
axis of the barb. 
 
5.4.2 Reverse twist 
 
The two line wires shall be twisted partially clockwise and partially anticlockwise. The barbs shall be 
placed at the points where the direction of twist changes from clockwise to anticlockwise. At these 
points the barbs shall be wrapped around the two line wires, two rounds each of barbed wire. The 
barbs shall have four points, approximately 90° apart in the plane at right angles to the line wire. 
 
5.4.3 Other twists 
 
The barbed wires in 3.4.1 and 3.4.2 shall normally be formed twisted together with an appropriate lay 
of 50 mm maximum with barb spacing of 75 mm ± 5 mm, 100 mm ± 10 mm or 150 mm ± 10 mm 
between centres for both low and high tensile. 
 
© EAC 2020 – All rights reserved 4
  
 
 DEAS 135:2020 
5.4.4 Joints 
 
Packed rolls shall not have more than one twist joint in case the wire breaks during formation. 
 
5.4.5 Packed rolls weight 
 
Barbed wires shall be packed in rolls of nominal weights of 20 kg or 25 kg. Tolerance for weight shall 
be -1% to +2%. 
 
 
6 Requirements for galvanized wire netting 
 
6.1 Preferred wire diameters, mesh sizes and width of netting 
 
Wires used for wire netting shall meet the requirements of Clause 2 of this standard. 
 
6.1.1 Preferred nominal wire diameters shall be as given in Table 1,   
 
6.1.2 The netting shall be manufactured in mesh and the width shall be as indicated in Table 4. For  
mesh sizes see Figure 1. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
© EAC 2020 – All rights reserved 5
  
 
 DEAS 135:2020 
 
Table 4 — Mesh sizes and widths of wire hexagonal netting  
 
    Width of roll,    
Mesh size and mesh 
details     (mm)    
          
 300  600 900   1200   1500 1 800  2100 
          
10 mm   X  X     
          
12 mm X X X  X  X X X 
          
20 mm X X X  X  X X X 
          
25 mm X X X  X  X X X 
          
32 mm X X X  X  X X X 
          
40 mm X X X  X  X X X 
          
50 mm X X X  X  X X X 
          
75 mm 
X X X  
X  
X X X 
2 ply selvedge   
         
          
100 mm 
X X X  
X  
X X X 
2 ply selvedge   
         
          
100 mm   
X  
X     
3 ply selvedge        
         
          
100 mm          
1 centre strand   X  X  X   
3 ply selvedge          
          
 
 
X denotes a mesh size and roll width combination which is normally available. 
 
Note: Other sizes may be accepted for special orders only as agreed between the purchaser and 
manufacturer. 
 
 
 
 
 
 
 
© EAC 2020 – All rights reserved 6 
 
 
DEAS 135:2020  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Figure 1 — Mesh size 
 
 
 
 
6.2 Tolerances 
 
Mesh size and width shall be subjected to the following tolerances: 
 
(i) mesh size ± 20 %; 
 
(ii) width ± 5 %. 
 
6.3 Nominal lengths 
 
Wire netting shall be supplied in roll lengths of  18 m, and 30 m subject to a tolerance of - 1 % + 
unlimited. 
 
 
7 Specification for chain link fencing 
 
7.1 Type of wire 
 
The wire used for chain link fencing shall meet the requirements of Clause 2 of this standard. 
 
Wire used for chain link fencing may be galvanized, and/or plastics coated to have two grades as 
given in 5.3.1. 
 
 
 
 
 
 
 
© EAC 2020 – All rights reserved 8
  
 
 DEAS 135:2020 
 
7.2 Preferred wire diameters, mesh sizes and width 
 
5.2.1 Diameter 
 
Galvanized wire shall be of any nominal diameter specified in Table 5 . 
 
5.2.2 Plastics thickness 
 
Plastics radial thickness shall be minimum 10% of the core diameter. 
 
5.2.3  Chain link dimensions 
 
Mesh sizes and mesh diameters and widths shall be as specified in Table 5. 
 
TABLE 5 — Mesh sizes and wire diameters and widths of chain link fencing   
      Width of chain 
link, +2%, -0%    
       
(mm)     
Mesh 
size, ±5% Nominal 
wire          
          
mm diameter,            
          
mm           
 
 900 1 200 1 500 1 800   
2100  2400  2700 3 000  3300    
25 2.0 X X X X  X X    
            
40 2.0 X X X X  X X X X X 
 2.5 X X X X  X X X X X 
 3.0 X X X X  X X X X X 
            
50 2.0 X X X X  X     
 2.5 X X X X  X X X   
 3.0 X X X X  X X X X X 
 3.55 X X X X  X X X X  
 5.0   X X  X X X X  
            
 2.0 X X X X  X     
 2.5 X X X X  X X X X  
 63 3.0 X X X X  X X X   
 3.55 X X X X  X X X X X 
 5.0   X X  X X X X  
            
75 2.5 X X X X  X X X X  
 3.0 X X X X  X X X   
            
 
 
 
© EAC 2020 – All rights reserved 9 
 
 DEAS 135:2020 
 
X denotes a mesh size and roll width combination which is normally available. 
 
7.3 Requirements of plastics coated wire 
 
7.3.1 Plastics coated wire shall have hot-dip galvanized core wire of annealed condition.  
 
a)  
 
 
5.3.2 The plastics covering shall be applied to the wire using a compound manufactured from a  
composition based on vinyl chloride homopolymer of the suspension or granular type chloride, and no 
copolymer or emulsion polymer shall be included. 
 
5.3.3 The vinyl chloride homopolymer shall be mixed with appropriate primary plasticizers, heat and  
light stabilizers, lubricators and pigments. No extender or filler other than specified material shall be 
added to the compound. 
 
5.3.4 Not more than 5 % of clean, once reworked material, which shall be of the same composition,  
shall be added to the virgin material from which the compound is to be manufactured. 
 
7.3.5 The colourfastness of the compound to daylight shall be not less rating 6, this shall be verified  
by preparing a sheet formed from compound in accordance with BS 2782, Method of test for plastics . 
 
7.3.6 Physical requirements shall be as given in Table 6. 
 
Table 6 — Physical characteristics of plastics coating  
Physical  Value 
  
Tensile strength, (MPa) 21 Mpa, min. 
Elongation at break 150 %, min. 
Softness 5 - 15 softness number 
Cold bend temperature -10°C, max. 
Cold flex temperature before ageing +15 °C, max.  
  
Cold flex temperature after ageing +20 °C, max.  
  
Water absorption 100 mg, max. 
  
 
 
The above requirements shall be in accordance with BS 2782, Method of test for plastics. 
 
7.3.7 For the finish of plastics coated wire, the extruded plastics covering shall be smooth, and  
substantially free from cracks, blisters and non-uniformity. The variation in radial thickness of the 
coating shall be within ± 25 % nominal radial thickness. 
 
 
 
© EAC 2020 – All rights reserved 10
  
 
 DEAS 135:2020 
 
7.4 Tolerances 
   7.4.1 Plastics coated wire shall be subjected to a tolerance of 10 % of the nominal wire diameter. 
7.4.2 Mesh sizes shall be subjected to 10 % tolerances measured at right angles between wires. 
 
7.5 Nominal length 
Nominal length shall be as specified in Table 1. 
 
 
8.0 Labelling 
8.1Barbed wire 
Every roll of barbed wire shall be labelled legibly with the following: 
a) Name of the manufacturer/trademark,  
b) Length of barbed wire,  
c) Nominal wire diameters of line wire and point wire in mm,  
d) Batch number, 
e) mass of the roll in kg. 
f) Country of origin 
 
8.2 Galvanized wire netting and Chain link 
Every roll of galvanized wire netting shall be labelled legibly with the following: 
a) Name of the manufacturer/trademark,  
b) Mesh size,  
c) Nominal wire diameters,  
d) Batch number  
e) Length and width in m.. 
f)  Country of origin 
 
9.0 Sampling 
 
Unless otherwise agreed upon between the manufacturer and the purchaser, the sampling plan shall 
be according to Table 7. 
 
Table 7: Scale of sampling 
 
S/No. Number of Reels in the Lot Number of Reels to be Selected 
01 Up to 25 3 
02 26 to 50 4 
03 51 to 150 5 
04 151 to 300 7 
05 301 and above 10 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
© EAC 2020 – All rights reserved 11
 
  
 
 Bibliography 
 
IS 278:2009, Galvanized steel barbed wire for fencing — Specification 
BS 2782, Method of test for plastics  
 
 
 
.  
 
 DEAS 135:2020 
 
Annex A  
(normative) 
 
Test methods for weight and uniformity of zinc coating 
 
 
 
 
 
A.1 Determination of weight of coating 
 
The weight of coating may be obtained by either a gravimetric method or a volumetric method. The 
latter has an acceptable degree of accuracy and has the advantage of rapidity. It is therefore the 
preferred method for routine testing of all the sizes of wire, which can be conveniently accommodated 
in the measuring apparatus. In case of a dispute, the gravimetric method shall be accepted as the 
referee method. 
 
 
A.2 Gravimetric method 
 
A.2.1 Reagents 
 
The following reagent shall be used: 
 
Antimony chloride solution — Dissolve 20 g of antimony trioxide or 32 g antimony trichloride in 100  
ml hydrochloric acid, of specific gravity not less than 1.14 stripping solution. Add 5 ml of the antimony 
chloride solution to every 100 ml of hydrochloric acid, of specific gravity not less than 1.14. 
 
A.2.2 Test piece 
 
For wires of 3 mm diameter and larger, the length of the test piece shall be not less than 200 mm. As 
a guide to the length for smaller sizes of wire, this should be such that the weight in grams is 
numerically not less than four times the diameter in millimetres. 
 
After cleaning the test trichloroethylene, the weighed to the nearest piece in a suitable organic 
solvent, for example, wire shall be wiped dry with a clean cloth and 0.01 g. 
 
A.2.3 Stripping the zinc 
 
The galvanized coating shall be stripped from the steel wire by complete immersion of the test piece 
in any convenient volume of the stripping solution. The same solution may be repeatedly used, 
without further additions of antimony chloride solution, until the time of stripping becomes 
inconveniently long. The temperature of the stripping solution should not be allowed to exceed 38 °C 
and the number of test pieces immersed at anyone time shall not exceed 3 per 100 mL of solution. 
 
As soon as the violent chemical action has ceased the wire shall be removed from the acid, washed 
thoroughly in running water and wiped dry. The diameter of the wire shall then be determined to the 
nearest 0.02 mm by taking the average of two measurements at right angles to each other. Each 
piece of stripped wire shall then be weighed to the nearest 0.01 g. 
 
 
 
 
© EAC 2020 – All rights reserved 12
  
 
 DEAS 135:2020 
 
A.2.4 Calculation 
 
The weight of zinc per unit area of the steel surface shall be derived from the weight of zinc on the 
test length and the surface area of the steel. By taking into account the density of the steel as 7.85 
kg/dm3, the formula can be simplified to this form. 
 
Weight of coating per unit area of steel surface = Kdr 
where 
 
K = 7.85×1000 =1960 4   
d is the diameter of stripped wire; and   
r = original weight − stripped weight in 
grams stripped weight  
 
If the stripped wire diameter d is measured in millimetres then weight of coating = 1 960 dr g/m2. 
 
 
A.3 Gas volumetric method 
 
A.3.1 Explanation 
 
The volumetric method of determining the weight of coating depends on the fact that a metal 
dissolved in acid always releases a quantity of hydrogen proportional to the amount of metal 
dissolved, that is, the chemical equivalent of the metal in question. 
 
One gram of zinc releases 0.343 litres of hydrogen at a temperature of 0 °C and a pressure of 1 mbar. 
With very large wires, problems of test piece preparation and damage to the glass burette may be 
introduced. This method of determination is therefore usually limited to wires of maximum diameter 5 
mm. 
 
A.3.2 Reagents 
 
The same reagents as specified for the gravimetric method shall be used (see A.2.1). 
 
A.3.3 Apparatus 
 
The apparatus consists of a 100-ml glass burette fitted with a stopcock at the top and bottom and 
connected at the bottom with a rubber tube to a reservoir. The apparatus is shown in Figure A.1 set 
up for the commencement of the test. 
 
The 100-ml burette shall be graduated to at least 0.5 mL subdivisions. 
 
Where small sizes of wire, less than 1.5 mm diameter, are regularly tested, it may be found useful to 
have a 50-ml burette of about the same length and graduated to at least 0.2 mL subdivisions. 
 
 
 
 
 
© EAC 2020 – All rights reserved 13
  
 
 
DEAS 135:2020  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Figure A.1 — Apparatus ready for test 
 
A.3.4 Test pieces 
 
From a straightened and undamaged length of wire, test pieces of the required length shall be 
accurately cut (error not more than 1 %). The most suitable length of a test piece depends upon the 
size of the burette, diameter of wire and expected weight of coating. The lengths indicated in Table 
A.1 shall usually be found convenient. 
 
© EAC 2020 – All rights reserved 14
  
 
                 DEAS 135: 2020 
 Table A.1 — Length of test piece    
     
Galvanized wire diameter  Length of test piece   
     
Over, Up to and Including,  For a 100 -mL burette,  For a 50 -mL burette,   
mm mm mm mm  
     
0,45 0,85 - 200  
     
0,85 1,06 200 150  
     
1,06 1,8 100 75  
     
1,8 3,6 75 -  
     
3,6 5,0 50 -  
     
 
 
A.3.5 Procedure 
 
The acid reagent shall be poured into the reservoir C so that it shall completely fill the burette leaving 
a small portion in the reservoir when in an elevated position. 
 
To carry out a test, the height of the reservoir C shall be adjusted so that the acid reagent just fills 
the burette up to the stopcock A with the bottom stopcork B closed. The test piece cut to the 
specified length shall be dropped into the burette and the stopcork A immediately closed. The 
zinc coating shall dissolve rapidly and liberate hydrogen, and the test shall be continued until 
evolution of hydrogen, but for a few fine bubbles, has ceased. 
 
The reservoir shall then be lifted from its supporting ring alongside the burette until the levels of the 
acid reagents burette and the reservoir are equal, as shown in Figure A.2, volume of hydrogen is 
read off on the burette scale. 
 
When the test is concluded, stopcock A shall be opened and all acid reagent drawn from the burette 
by lowering the reservoir to a position below stopcock B. 
 
Stopcock B shall then be opened to eject the test piece and closed again after which the procedure 
given above shall be repeated for the succeeding test. 
 
When long test pieces are necessary, rapid entry into the burette may to drop two short pieces and it 
may be more convenient simultaneously through the stopcork. 
 
The stripped wire shall be washed dry and diameter measured. 
 
 
 
 
 
 
 
 
 
© EAC 2020 – All rights reserved 15
  
 
 
DEAS 135:2020  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Figure A.2 ― Apparatus after taking reading  
 
A.3.6 Calculation 
 
The weight of zinc coating shall be calculated from the formula: 
 
Weight of coating/unit area of steel surface = dlv × f 
where 
 
 
 
© EAC 2020 – All rights reserved 16
  
 
 DEAS 135:2020 
 
v is the volume of hydrogen evolved in millilitres (mL);  
 
d is the stripped wire diameter; and  
 
l is the length of test piece.  
 
Where length and diameter are in millimetres, f = 872 to give a weight of coat in grams/metre. 
 
A.3.7 Correction for temperature and barometric pressure 
 
The factor (f) has been calculated for a temperature of 18 °C and a barometric pressure of 1 bar. If 
the atmospheric pressure is outside the range of 987 mbar - 1 040 mbar or if the temperature is 
outside the range of 16 °C – 20 °C, apply the appropriate correction factor from Table A.2. If the 
combination of pressure and temperature results in a correction factor within ± 0.02 of unit (see 
outlined zone in Table A.2), then the factor need not be applied. 
 
Where the test result is within 5 g/m2 of the specified value, it shall be desirable to check the 
atmospheric pressure and temperature in case a negative correction shall be necessary. 
 
Where climate or altitudes affect the test conditions, a permanent correction should be applied to the 
factor. At high altitudes it shall be convenient to have a burette of greater capacity than 50 ml or 100 
ml. Table A.2 gives a list of corrections for temperature and pressure. 
 
 
A.4 Test for uniformity of coating —'Preece' Dip method 
 
A.4.1 Reagents 
 
The following reagents shall be used: 
 
Copper sulfate solution, made by dissolving approximately 36 g of crystalline copper sulfate  
(CuSO 4.5H2O) in each 100 ml of distilled water. The water may be heated to aid solution of the 
crystals, but if heated the solution shall be allowed to cool before neutralizing. 
 
For neutralization, the solution shall be shaken with an excess of cupric hydroxide (about 1 g/litre of 
solution) and allowed to stand, preferably for at least 24 h, before filtering or decanting the solution 
from the sediment. 
 
About 0.7 g/L of cupric oxide may be used in place of the hydroxide, provided the solution shall be 
allowed to stand for, least 48 h before filtering from the sediment. 
 
The specific gravity of the test solution shall be 1.186 at 18 °C. Adjustment may be made by adding 
distilled water or solution of higher specific gravity, as appropriate. 
 
The solution shall be discarded and replaced with fresh solution after six samples have been tested. 
 
A.4.2 Apparatus 
 
The following apparatus is required: 
 
 
 
 
 
© EAC 2020 – All rights reserved 17
  
 
 DEAS 135:2020 
 
A glass container of internal diameter not less than 50 mm for wires of 2.8 mm diameter and smaller, 
or 75 mm for larger wires, shall be filled with the copper sulfate solution to a depth of at least 100 mm. 
 
A.4.3 Test pieces 
 
The test piece shall be not less than 150 mm in length and shall be undamaged as far as possible. 
The test piece may be hand straightened and shall be cleaned with a volatile organic solvent and then 
wiped dry with a clean soft cloth. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
© EAC 2020 – All rights reserved 18
 
  
 
 Table A.2: Temperature and pressure corrections  
 
       Atmospheric 
pressure,         
Temperature         
mbar        
                
°C                   
693 720 747 773 800 827   
853  
880  
907 933  960 977 1 014 1 0401 067     
                   
10 0.703 0.7300.758 0.784 0.811 0.839  0.866 0.992  0.920 0.947 0.974 1.001 0.028 1,0551.082
12 0.698  0.7250.752 0.779 0.806 0.833  0.860 0.886  0.914 0.940 0.967 0.994 1.020 1.0481.075
14 0.694  0.7200.747 0.774 0.800 0.827  0.854 0.880  0.908 0.934 0.960 0.988 1.014 1.0401.068
16 0.689 0.7150.742 0.768 0.795 0.822  0.848 0.874  0.901 0.927 0.954 0.981 1.007 1.0331.060
18 0.684  0.7100.737 0.763 0.789 0.816  0.842 0.868  0.895 0.921 0.947 0.974 1.000 1.0261.053
20 0.679 0.7050.732 0.758 0.783 0.810  0.836 0.862  0.889 0.915 0.940 0.967 0.993 0.0191.046
22 0.674 0.7000.727 0.752 0.778 0.805  0.830 0.856  0.882 0.908 0.934 0.960 0.986 1.0121.038
24 0.670  0.6960.722 0.748 0.773 0.800  0.825 0.851  0.877 0.903 0.928 0.955 0.980 1.0051.032
26 0.666  0.6910.717 0.742 0.769 0.794  0.819 0.845  0.871 0.896 0.921 0.947 0.973 0.9981.025
28 0.661  0.6870.713 0.738 0.763 0.789  0.814 0.839  0.865 0.891 0.916 0.942 0.967 0.9921.018
30 0.657  0.6820.708 0.732 0.757 0.783  0.808 0.833  0.859 0.884 0.909 0.935 0.960 0.9851.011
                   
 520  540 560 580 600 620   640  660  680 700  720 740 760 780 800 
                   
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
© EAC 2020 – All rights reserved 19 
 
 DEAS 135:2020 
 
Height of Barometer, mm Hg. 
 
A.4.4 Temperature 
 
At the commencement, and during the progress of the test, the temperature of the test pieces and of the 
solution shall not vary outside the limits of 18 °C ± 2 °C. 
 
 
A.4.5 Procedure 
 
It is preferable that not more than three test pieces be immersed in the solution at one time. The test pieces 
shall not be disturbed, and the solution shall not be agitated. 
 
The test piece shall be subjected to successive dips of exactly 1 min. After each dip the sample shall be 
removed and immediately rinsed in clean running water and wiped dry with a clean soft cloth. If running 
water is not available, the rinsing water shall be changed frequently so that there is no obvious 
contamination with copper sulfate solution. 
 
Half-minute dips, where specified, shall be given after the completion of all the 1 min dips. 
 
A.4.6 Examination 
 
After the specified number of dips, the final rinsing and wiping dry, the test piece shall not show any adherent 
bright deposit of metallic copper on the steel. Any deposit of metallic copper within 25 mm of the cut end shall 
be disregarded. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
© EAC 2020 – All rights reserved 20 
 
  
DEAS 135:2020  
 
 
Annex B 
 
(Informative) 
 
Formula for Length per 1kg (m) and mass per metre run (g/m) 
 
 
1. Length per 1kg (m) = 1 ÷ (diameter*diameter x π/4 x density of steel x 10-6) 
 
Where:  
 
Diameter in mm 
 
Density of steel 7850kg/m3 
 
 
2. Mass per metre run (g/m) = 1000 ÷  Length per 1kg (m) 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
© EAC 2020 – All rights reserved
 
.