DRAFT TANZANIA STANDARD                       TDC 3 (1140)  CD 3 
                                                                                                First Edition                                          
©TBS 2018 All rights reserved                                                                      First edition 2022  
 
 
Textiles — Woven High -Density Polyethylene/Polypropylene 
(HDPE/PP) Shopping bags — Specification  
 
 
 
 
 
 
 
 
 
  
 
 
 
 
 
 
 
 
 
 
 
 
 
TANZANIA BUREAU OF STANDARDS   
1 
©TBS 2018 All right reserved                                                                     First  edition 2022  
              TDC 3 (1140)  CD 3 
Foreword  
This Draft Tanzania Standard is being developed by the Household  Textile Technical Committee 
under supervision of the Textile s and Leather Division Standards Committee and it is in accordance 
with the procedures of the Bureau.  
 This Draft Tanzania Standard has been prepared with assistance drawn from:  
 Local Shopping bags manufacturers.  
 TZS 1257  Textiles – Specification for open mouth woven poly -sacks made from 
polypropylene tape - yarns  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
 
2 
©TBS 2022 All rights reserved                                                                      First edition 2022  
  
1 Scope  
This Draft Tanzania Standard specifies requirements for the materials, dimensions, and performance 
of woven HDPE/PP shopping bags.  
  
2 Normative References  
For the purpose of this Draft Tanzania Standard the following references shall apply :  
a) TZS 4 Rounding off numerical values.  
b) TZS 21 Textiles - Woven or knitted fabrics - Determination of mass per unit length and -    per 
unit area.   
c) TZS 22 Textiles - Woven fabrics Determination of breaking load and extension.  
d) TZS 24 Textiles - Tests for colour fastness – Colour fastness to was hing: Test 4.  
e) TZS 26 Textiles - Determination of conductivity, pH, water -soluble matter, chloride and 
sulphate in aqueous extracts.   
f) TZS 40 Textiles - Tests for colour fastness – Colour fastness to light: Daylight.  
g) TZS 138 Textiles - Test for colour fas tness to rubbing.  
h) ISO 3451 Plastics — Determination of ash — Part 1: General methods.  
i) ISO 13936 – 1, Textiles — Determination of the slippage resistance of yarns at a seam in 
woven fabrics — Part 1: Fixed seam opening method.  
j) ISO 13936 – 2, Textiles — Dete rmination of the slippage resistance of yarns at a seam in 
woven fabrics — Part 2: Fixed load method.  
k) ISO 13937 - 1, Textiles — Tear properties of fabrics — Part 1: Determination of tear force 
using ballistic pendulum method (Elmendorf).  
3 Terms and Defini tions  
 
For the purpose of this Draft Tanzania Standard the following definitions shall apply:  
3.1 polymer (polymerization)  
combination or association of molecules that may be of one compound or more reacting 
simultaneously to form a regular system of molecules behaving as one unit  
  
3.2 polypropylene (PP)  
synthetic resin built up by the polymerization of propylene.  
 
3.3 high density polyethylene (HDPE)  
a thermoplastic polymer produced from the monomer with a high strength -to-density ratio.  
 
3.4 polypropylene (PP) tape yarns  
flat yarn composed of polypropylene polymer.  
 
  
 
3 
©TBS 2022 All rights reserved                                                                      First edition 2022  
 3.5 high -density polyethylene ( HDPE ) tape yarns  
flat yarn composed of high density polyethylene polymer.  
 
3.6 fabric weaves  
pattern s of interlacing of the warp (the tapes running in the machine or longitudinal direction of the 
woven material) and the weft (the tape yarns in the transverse direction).  
  
 
3.8 woven PP/HDPE fabric  
sheet material woven from PP/HDPE tape yarns.  
  
3.9 coated fabric  
fabric coated on one or both sides with suitable polymer.  
  
3.10 poly –sack  
flexible container, made from fabric manufactured from woven PP/HDPE tape yarns.  
 
 4 Materials  
  
4.1 Fabric  
4.1.1 The weave of the fabric shall be woven from PP/HDPE tape yarn having a minimum width of 
2mm.  
 
4.1.2 The fabric shall be uncoated or coated on one side or both.  
  
4.2 Stitch threads  
The stitch ing thread shall be made from either;   
a) Polypropylene, or  
b)  Other materials provided they are not adversely affected by the expected climatic conditions 
in transit, storage and use.  
 
5 Dimensions  
Unless otherwise agreed to between the buyer and the seller, the dimensions of the shopping bags 
shall be as declared subject to a tolerance of ±2 mm  
 
6 Construction  
6.1 shopping bag  
The shopping bag shall be produced either;  
a) From material woven as a tub e, or  
b) From flat woven material and cut to the required length.  
 
6.2 Edge sealing  
All edges shall be sealed to prevent leakage.  
 
6.3 Base closure  
The base closure shall be such as to ensure compliance with the performance required.  
6.4 Turned -over and stitched  
Where the base closure is affected by a turned -over and stitched seam, the turn over shall be 2.0 cm 
minimum, and the stitch line shall be done with one row of the chain stitch 1.0±0.3 cm from the base 
so formed and shall pass through all four thicknesses of the material.   
 
4 
©TBS 2022 All rights reserved                                                                      First edition 2022  
  
 
 
6.5 Seam  
The stitching shall be done at the bottom and at the mouth of the sack excluding value. It shall be 
done with a single or two rows of the lock or chain stitches.  
 
6.6 Mouth  
The mouth of the bag shall be either;  
 
a) plain, formed from the selvedge or from sealed raw edge, or 
 
b) hemmed with a single or double fold over stitched continuously round the mouth of the sack.  
 
6.7 The handle  
The handle of the shopping bag if not attached on the top, shall be located at a distance of 5 cm from 
the top edge of the bag.  
 Table 1 -Perfomance Requirements for the woven sacks.  
SN Characteristics  Requirements  Test method  
1 Average breaking strength ( ravelled  
strip method, (200mm x 50mm), -min, 
N 
i) Width wise  
ii) Length wise   
 
 
500 
500  
 
TZS 22  
2 Elongation at break of fabric (%), min  
i) Length wise  
ii) Width wise   
 
20 
18 TZS 22  
3 Breaking strength of bottom seam, 
ravelled  strip method, N , min 250 ISO 13936  
4 handle pull strength, N, min.  50 Annex B 
4 Mass per unit area, g/m2, min,   TZS 21  
Unlaminated fabric  50 
Laminated fabric  65 
5 Number of yarns per decimetre , min  
I) Ends/dm  
II) Picks/dm   
40 
40 TZS 20  
6 Average breaking strength and 
elongation at break of UV stabilized 
HDPE/PP fabric after been exposed 
to UV radiation and weathering, min.   
Not less than 50% of original 
strength  Annex A   
 
5 
©TBS 2022 All rights reserved                                                                      First edition 2022  
 7 Ash content (for UV stabilized 
fabrics), max per  cent.  2.2 ISO 3451 – 1: 2008  
Method A.  
8 Capacity  shall be  as declared   Visual  
9 Dimension  shall be as  agreed to between 
the buyer and the seller with a 
tolerance of ±2  cm  TZS 44  
 
7. Printing, packing and marking  
7.1 Printing on shopping bags  
7.1.1 The bags shall be printed with food grade indelible printing ink.  
7.1.2 Each shopping bag shall be marked with the following;  
a) Manufacturer’s name and address,  
b) Carrying capacity,  
c) Recycling logo.  
d) Dimensions  
7.2 Marking of packed bale  
The following information shall be marked on each bale with indelible ink.  
a) Name of the manufacturer;  
b) Type and/or size of the  sack;  
c) Gross mass of the bale;  
d) Date of manufacture;  
e) Any other information required by the buyer;  
f) Identification Mark;  
g) Number of sacks.  
 
Note 2  - Each sack  shall be compulsory marked with visible recycling logo as given below at a space on bottom 
of the bag compatible with the artwork  of the buyer for printing the sack and bale.  
Note 2 - For sacks with similar properties of a laminating film, the sack shall b e compulsory marked with a visible 
recycling logo below at a space on bottom of the bag compatible with the artwork of the buyer for printing the 
sack and bale.  
 
 
Put the clear and visible recycling logo  
Fig 1 Recycling Logo  
 
 
6 
©TBS 2022 All rights reserved                                                                      First edition 2022  
  
 
ANNEX A  
(Normative)  
UV RESISTANCE TEST  
A – 1 To determine the effect of UV radiation and weathering on the breaking strength, the 
HDPE/PP Woven fabrics shall be exposed as given in A - 2 and A – 3. 
 
A – 2 TEST PROCEDURE  
The test shall be carried out with fluorescent UV – Lamp type B (313nm or its equivalent).  
The duration of the test shall be 192h (that is eight days) in continuous mode.  
The test cycle shall be: 8h at 60   ± 3  with UV – radiation alternating with 4h at 50   ±3  
condensation. Irradiance level throughout the test shall be maintained at 0.63 (+0.04/ -0) W/m2. 
A – 3 TEST PROCEDURE  
A – 3.1 Determine the original average breaking strength of fabric as per test method specified 
in IS 1969 (part 1)  
A – 3.2 Expose the specimens alternately to ultraviolet light and condensation in respective test 
cycle in continuous mode for total 192h.  
The type of fluorescent UV lamp, the timing of the UV and condensation exposure and the 
temperature of the UV exposure and c ondensation shall be specified in A -2. 
A – 3.3 Determine the average breaking strength of the fabric separately after UV exposure as 
mentioned above.  
A – 3.4 Determine the per cent  retention of original strength as follows:  
Percentage retention of original  breaking strength =  
         
Where ,  
a) a= average breaking strength before UV exposure as obtained in A – 3.1 
b) b= average breaking strength after UV exposure as obtained in A – 3.3 
NOTES  
1. The UV source is an array of fluorescent lamps (with lamp emission concentrated in the UV range).  
2. Condensation is produced by exposing the test surface to a heated, saturated mixture of air and water vapour, 
while the reverse side of the test specimen is exposed to the cooling influence of ambient room air.  
 
 
 
 
 
  
 
7 
©TBS 2022 All rights reserved                                                                      First edition 2022  
  
Annex B  
(Normative)  
 
Determination of pull strength of the handle (Pulling tester machine)  
 
B-1 Determine and mark the end point of all the handles tail  
B-2 As per distance between the upper clamp or jaw, reduce the length of the bag by knot or stitch to 
get the clear look to the handle loop   
B-3 Hook the handle loop to the upper clamp or jaw   
B-4 From bottom of the non -woven bag, fold 8  cm and grip the fold line to the lower clam or jaw   
B-5 At constant transverse rate of 20  cm per minute, measure the breaking point for 5 specimens to 
evaluate the puling strength according to TZS 22.