DRAFT EAST AFRICAN STANDARD  
DEAS 11 :2018  – Hot dip galvanized  plain and corrugated 
steel sheets – Specification  
 
 
 
  
 
 
 
 
 
 
 
 
 
 
EAST AFRICAN COMMUNITY  
 
 
   
  
 
 
 
 
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2  
  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 devel op 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 c irculated 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 sub ject 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 11:2018 was prepared by Technical Committ ee EASC /TC 035 TC Steel and Steel Products  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
    
 Galvanized plain and corrugated steel sheets – Specification  
 
 
1. Scope  
 
This East Africa Draft Standard specifies requirements, test methods and sampling for 
galvanized plain and cor rugated steel sheets for roofing, cladding, fencing, fabrication and 
general use . 
 
. 
 
This East Africa Draft Standard  does not cover all the special purpose profiles . 
 
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 reference 
document (including any amendments) applies.  
  
EAS 196, High strength low – alloy carbon steel for hot rolled a nd cold rolled sheet - specification  
  
3. Definitions   
  
For the purposes of this East Africa Draft Standard , the following definitions shall apply:  
  
3.1 Galvanized sheets   
  
Steel sheets with a uniform coating of zinc applied by the hot -dip process  
  
3.2 Corrugated sheets    
  
Galvanized steel sheets which are mechanically formed to obtain regular, sinusoidal, profiles, as 
shown in figure 1  
  
  
  
Figure 1 — Profile of corrugated sheets  
  
 
3.3 thickness  
 thickness of the base metal.    
 
 
  
    
    
3.4 Plain    
  
The flat or even sheets without any relief forms  
  
3.5 Pitch    
  
The distance between two corresponding and consecutive points on the corrugated steel sheets along 
its width  
   
  
4. General requirements   
  
4.1 Dimensions   
  
 
4.1.1. Length    
  
When measured in accordance with 9.2.2, the length of sheets shall be as specified in Table 3  
  
 4.1.2 Width    
  
The width of plain and corrugated galvanized sheets when measured in accor dance with 9.2.4 shall 
be as specified in Table 2.  
  
4.1.3  Thickne ss   
  
The thickness of galvanized plain and corrugated sheets shall be expressed in gauges. The 
corresponding thickness in millimetres s hall be as specified in Table 1 .  
  
 
4.1.4   Squareness   
  
When measured in accordance with 9.2.3, the distance between  diagonally opposite corners of the 
sheet shall not differ by more than 10 mm.  
  
4.2 Profile   
  
4.2.1  Depth   
   
The depth of corrugations shall be 18 mm ±1.5 mm, when measured in accordance with 9.2.6.  
  
4.2.2  Pitch   
   
The pitch of the corrugations shall be 76 mm ± 2 mm when measured in accordance with 9.2.5.  
  
4.3 Tensile strength    
  
The tensile strength of plain and corrugated galvanized sheets when determined in accordance with  
9.2.7 shall be not less than 300 N/mm. The yield strength shall be n ot less than 210 N/mm  
 
 4.4 Hardness  
The hardness properties of the steel sheets shall be as follows:  
For 32G and 30G sheets to be  full hard  and for 28G and above sheets to be full hard or half hard  
 
  
 4.5 Resistance to bending    
  
When tested in accordan ce with 9.2.8, the sheet shall not crack, flatter or splinter.  
  
4.6 Freedom from defects    
  
The sheets shall be uniform, clean and free from defects that would adversely affect their use.  
  
4.7Finish    
  
The finish on plain and corrugated galvanized sh eets shall be ‘Mill Finish.  
  
Table 1 — Base metal thickness of plain and corrugated sheets  
  
Gauge  Thickness (mm)   Tolerance (± 
%)  
32  0.20   5 
30  0.25   5   
28  0.32   5 
26  0.40   5 
24  0.50   5 
22  0.63   5 
20  0.80   5  
18  1.00   5  
16  1.20   5  
14  1.50   5  
12  2.00   5  
10  2.60   5  
  
NOTE: Gauge 32 sheets, should be clearly marked “not for roofing”   
   
 
Table 2 — Nominal width of plain and corrugated sheets  
  
Width of plain sheets and sheets 
before corrugation ± 5 %  Number of corrugations  Total corrugated width 
± 2.5 %  
1220  14  1100  
1150  13  1025  
1070  12  950  
1000  11  875  
914  10  800  
845  9  725  
762  8  645  
  
     
  Table 3 — Nominal length of plain and corrugated sheets  
  
  
Nominal length, mm + 0.5 %, -0 %   
Plain sheets  Corrugated sheets  
2 000  2 000  
2 500  2 500  
3 000  3 000  
  
  
5. Galvanized processes (criteria of compliance)  
   
5.1 General requirement     
  
The steel sheets shall be manufactured in accordance with accepted current practice and  shall be 
from rolled milled steel made by a suitable process and meeting the requirements of EAS 196. The 
sheets shall be true to size and homogenous, with no trace of discontinuity of the zinc coating. They 
shall also be free from holes, tears, twists, c ambers and damaged edges and corners. Corrugations 
shall be parallel to the edges of the sheets.  
   
5.2 Zinc coating  
  
5.2.1 Zinc coating shall be carried out by the hot -dip process with smelter containing not less than98.5 
% pure zinc. The minimum mass o f zinc coating on the two sides of sheet and the 
corresponding thickness of zinc coating on each side shall comply with the classification 
specified in Table 4.  
   
5.2.2 The nominal mass of zinc coating per square meter, when tested according to methods 
specified in 8.1, shall correspond to the classification specified in table 4. The minimum 
values determined by the methods specified in 8.1, shall be as shown in table 4.  
  
5.2.3 Zinc coating adherence shall be such that there shall be no flaking or splin tering in the finished 
galvanized plain or corrugated sheet, when tested in accordance with 8.2.  
  
5.3 Classification of zinc coating    
  
Galvanized plain and corrugated steel sheets shall be classified into seven (7) classes depending on 
the mass of zinc  coating applied to meet different service and environmental conditions. The classes 
shall be as specified in table 4.  
  
 
Table 4 — Classification of galvanized plain and corrugated steel sheet  
  
  
Coatin 
g 
class    
Nominal 
mass on  
two sides  
  
  
g/m 2    
Minimum 
mass on two 
sides by 
weight  
method  
  
g/m2    
Minimum mass on 
two sides by 
antimony chloride 
method   
  
g/m2    
Nominal 
corresponding 
thickness on  
each side  
  
µm  
    
Minimum 
corresponding 
thickness on  
each side  
  
µm  
Z  515  412  360  35  25  
Y  450  360  315  31  22  
X  387  310  270  26  19  
A  305  244  214  21  15   
 B  244  198  183  17  13  
C  214  172  146  15  10  
D  183  137  122  13  9  
  
  
6. Marking   
  
6.1 Conforming sheets  
 
6.1.1 Marking  
   
Each galvanized plain or corruga ted steel sheet conforming to this East Africa Draft Standard  shall be 
permanently and indelibly marked with the following:   
  
a) Manufacturer’s name and/or trade mark.   
  
b) The base metal thickness expressed in gauge with word “GAUGE”  in full and 
millimetre .   
  
c) The coating class of sheet   
  
d) The batch identification.  
 
e) Gauge 32 sheets, should be clearly marked “not for roofing”  font size 12mm width 
in every 1m  along the length.  
 
 6.1.2 Packing  
 
 Sheets shall be packed in bund les as shown in the table below  
 
                         
Gauge, G  32 30 28 26 
Length(m)  2 2.5 3 2 2.5 3 2 2.5 3 2 2.5 3 
Number 
of sheet     23 19 16 18 14 12    
 
6.2 Non -conforming sheets    
  
All non -complying sheets shall be identified by cutting off all four corners at least by 75 m m along the 
edges diagonally and shall be marked “Rejected” with indelible ink.  
 
 7. Sampling  
7.1 General    
The sampling procedures in 7.2 and 7.3 shall be applied in determining whether a lot complies with 
the relevant requirements of the specification . 
The samples so taken shall be deemed to represent the lot.  
  
7.2 Sample for inspection and dimensional test     
  
7.2.1  From the lot, random sampling shall be done in accordance with Table  5. 
7.2.2 For the manufacturing industry, three sheets shall be taken  in every 8  h shift . 
   
7.3 Sample for other tests     
  
From the sample taken in accordance with 7 .2.1, take at random one sheet.       
    
Table 5 — Sampling plan  
  
  
Number of sheets    
Sample for inspection and dimensional tests, number of 
sheets  
1 - 16  1  
17- 48  2  
49 -100  3  
101- 160  4  
161 - 200  5  
Over 200  5 per 200 sheets  
  
8. Testing for zinc coating   
  
8.1 Mass of zinc coating  
  
8.1.1  Weight method    
  
The steel sheets are weighed before galvanizing. They shall be then passed throug h the galvanizing 
process and weighed again at the end of the process.  
   
NOTE – The Antimony Chloride Method will be used as the criteria for compliance and not the weight method.  
  
8.1.2  Antimony chloride method    
  
The test piece of minimum area 5 00 0 mm2 shall be weighed and then introduced into a zinc -stripping 
solution of one part antimony chloride and twenty parts hydrochloric acid (specific gravity 1.19), and 
shall remain therein until the coating has completely dissolved. The test piece shall be  taken out of the 
solution when the violent chemical reaction ceases, rinsed in running water, brushed to remove any 
loose substance, dried and weighed.   
  
 
 
8.1.3  Calculation   
  
The average of the gain or loss in mass (grams) calculated from the results  obtained from three test 
pieces shall represent the mass of zinc coating on both sides of each test piece (see Annex A).  
 
The results shall be expressed in grams per square metre (g/m2).   
 
8.2 Coating adherence test    
  
The test shall consist of subject ing the test piece to deformation by bending in one direction. The test 
piece shall either be bent mechanically or gripped in hand -operated device (mandrels may also be 
used) and bent until the two legs of the test piece are parallel to each other, i.e. th rough 180°.  
  
A second test piece shall be bent in the opposite direction.  
  
The sheets shall be bent round a diameter of 38 mm.  
 
  
  
  
 9. Inspection and physical tests   
  
9.1 Inspection     
  
Inspect the sample taken in accordance with 6 for compliance w ith 4.6 and 5.1.  
  
9.2 Dimensions   
  
9.2.1  Thickness    
  
Measure to the nearest 0.01 mm the thickness of each sheet in the sample of the sheets at any point 
at least 10 mm from an edge and end of the sheet .  
  
9.2.2  Length   
  
Place each sheet in the sample in turn on a flat rigid surface. Measure to the nearest 1 mm the length 
of each sheet along the centre line of the sheet.  
  
9.2.3  Square -ness    
  
Place each sheet in the sample in turn on a flat rigid surface. Measure to the nearest 1 mm the 
dista nce between the diagonally opposite corners of each sheet and record to the nearest mm the 
difference between the two measurements.  
  
9.2.4  Width  
  
  
9.2.4.1 Plain sheets   
  
Place each sheet in the sample in turn on a rigid surface. Measure to the near est 1 mm across the 
width of the sheet  
  
 
9.2.4.2 Corrugated sheets    
  
Place each of the sheets in the sample in turn on a flat rigid surface and measure to the nearest 1 mm 
across the width of the sheet. Choose at random a cross -section of the sheet and  if, because of the 
springy nature of the sheet, the underside of the downwards corrugations or troughs are not all in 
contact with the supporting surface, apply sufficient pressure to the upper surface of the sheet to bring 
the lower surface into full con tact with the supporting surface. Ensure that the application of pressure 
causes no deformation of the sheet other than that needed to bring the corrugations into contact with 
the rigid surface.  
  
Place the width gauge appropriate to the type of sheet bei ng tested across the sheet at any chosen 
cross -section and at right angle to the sides of the sheet and adjust the gauge to fit firmly over the 
outermost corrugations.  Determine whether the width of the sheet complies with the requirements of 
table 2. Bot h edges of the corrugated sheet shall be turned upwards while measuring  
  
9.2.5  Pitch   
  
With the sheet in contact with a flat surface, place a transparent graduated rule on edge across the 
sheet so that it rests perpendicularly on the crests of two adj oining corrugations far from the points of 
contact, and read the distance between them to the nearest 1 mm.  Repeat the process to improve 
your results by taking the average of five readings for the distance between several crests.  
  
NOTE. Any other appro priate method may be used to measure the pitch  
    
  9.2.6  Depth of corrugations    
  
With the initial rule lying flat across the corrugations at the edge of the sheet, use another graduated 
rule or calipers to measure the perpendicular distance between the ini tial rule and the rigid support.  
 
 NOTE. Any other appropriate method may be used to measure the pitch  
 
  
9.2.7  Tensile strength    
  
From the sample in Clause 7, prepare a tensile test specimen, after stripping off coating, by cutting a 
strip 30 mm x 80 m m, such that the length of the specimen is transverse to the direction or rolling of 
the sheet. The portion of sheet from which the test piece is cut shall be carefully flattened. Determine 
the tensile strength of the specimen. .  
  
If the tensile strength of the test specimen fails the requirements of 4.3, prepare two further test 
specimens and determine their tensile strength. If both specimens comply with the requirements, 
discard the results of the first specimen, but if either of the additional specimen s fails to meet the 
requirements, deem the sheet and the lot to be defective   
 
9.2.8  Bend test and coating adherence test   
  
A test specimen shall be selected in accordance with Clause 7 and shall be prepared to measure 10 
mm in width and 120 mm in leng th.   
  
It shall be cut with its length transverse to the direction of rolling of the sheet. Carefully bend the strip 
round a drum of diameter 38 mm (mandrels may also be used) until the edges of the specimen are 
approximately semi -circular. .   
  
If the sp ecimen cracks, prepare and test two further specimens in the same way. If both these test 
specimens comply with the requirements of 4.4, 4.5 and 5.2.3, discard the results obtained on the first 
specimen, but if either of the two cracks at the bend, deem th e sheet and lot to be defective . 
 
9.2.9 Hardness test  
The hardness test  of the steel sheets shall be in accordance to ISO 6507 -1:2018  
  
  
  
  
 
 
 
 
 
 
 
 
 
 
 
 
 
  
  
Annex A  
  
Reference method for determination of the zinc coating mass   
  
  
A.1 Principle  
  
Using  a specimen with a surface area of at least 5 000 mm2, the loss of mass in grams when the 
coating is dissolved, multiplied by 200, will represent the coating mass in grams per square meter of 
the product (for both sides).  
   
NOTE – To verify the mass of c oating, three specimens shall be cut and tested, one from the 
mid-width position and one from each side, no closer than 25 mm from the side edge of a 
sample piece approximately 300 mm in length on the coated width  
  
A.2 Reagent and preparation of the solu tion  
  
A.2.1 Reagent  
  
Hydrochloric acid (HCL = 1.19 g/cm3)  
Antimony tri -chloride  
  
A.2.2 Preparation of the solution   
  
This prepared solution permits the execution of numerous successive dissolutions under satisfactory 
conditions of attack of the co ating, both from the point of view of speed and accuracy.  
  
A.3 Apparatus  
  
Balance, capable of weighing samples to an accuracy of 0.01 g. For the test, use a take -off device.  
   
A.4 Procedure  
   
The following operations are applied to each sample:  
  
a) If necessary, degrease the sample with an organic solvent, which will not attack the coating, then 
dry the sample;  
  
b) Weigh the sample to an accuracy of 0.01 g;  
  
c) Place the sample in the hydrochloric acid solution with hexamethylenetetramine or antimony 
chloride inhibitor at an ambient temperature of 20 °C to 25 °C leave the sample immersed in the 
solution until the release of hydrogen ceases of only a few bubbles are released;   
  
d) After the attack, wash the sample and brush under running water, dry with a  cloth and then by 
heating to around 100 °C and cool or dry by blowing with warm air;  
  
e) Weigh the sample again to an accuracy of 0.01 g;  
  
f) Determine the difference between the mass of the coated sample and that of the sample without its 
coating. This dif ference, calculated in grams, represents the mass (m) of the coating.   
     
  A.5 Calculation   
 
  
The coating weight shall be obtained from the following formulas. Method 1 shall be the reference 
method in case of a dispute:  
  
  
  
Where   
  
C     is zinc  coating in g/m2;  
  
A     is area  of test specimen (length x width);  
  
W1  is weight (g) of test piece before stripping;  
 
W2 is weight (g) of test piece after stripping (base metal);  
  
t is  thickness (mm) of test piece after stripping (base metal);   
  
106 is conversion factor W is in g, t in mm, while C is in g/m2  
  
 7 850 is density of steel, kg/m3  
  
NOTE – Method 1 shall be used for regular pieces of specimen (either square or rectangular).  In case where it’s 
difficult to cut regular test piec es, e.g. the heavier sheet gauges, method 2 shall be used.