TDC12 (1302 ) DTZS  
             First  edition
 
DRAFT TANZANIA STANDARD
 
 
 
Agro textiles — Shade nets for agriculture and horticulture 
purposes — specification - Part 1: Shade Nets made from Tape 
Yarns.  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
TANZANIA BUREAU OF STANDARDS  
 
 
 
 Foreword  
This Draft Tanzania Standard is issued to help manufacturers /retailers  of shade nets for agriculture 
and horticulture purpose  to come up with products of defined quality . This Tanzania Sta ndard covers 
the requirements of shade nets made from tape yarns .   
In the preparation of this Tanzania Standard, assistance was derived from:  
IS 16008 (Part 1): 2016 - Agro textiles — Shade nets for agriculture and horticulture 
purposes — specification - Part 1: Shade Nets made from Tape Yarns.  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
 1. SCOPE  
This Draft Tanzania S tandard specifies  constructional , requirements , test methods, and sampling plan 
for shade nets manufactured from tape yarns for agriculture and horticulture purposes in 
protecting/increasing crop yield by providing  partially  controlled climatic conditions for the intended 
crops . 
2. NORMATIVE REFERENCES  
The following referenced documen ts 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.  
TZS 4: Rounding off numerical values  
TZS 21: Textiles — Woven or knitted fabrics — Determination of mass per unit length and per 
unit area.   
TZS 22: Textiles — Woven fabrics — Determination of breaking load and extension . 
TZS 40: Textiles — Tests for colour fastness — Colour fastness to ligh t Daylight   
TZS 44: Textiles — Woven or knitted fabrics — Determination of length and width   
TZS 534: Textiles  – Standard atmospheres for conditioning and testing  
 
3. TERMS AND DEFINITIONS  
For the purpose of this Draft Tanzania Standard, the following terms and definitions shall apply:  
3.1 shading factor   
percentage of light not transmitted through shade net.  
3.2 shade net 
structure enclosed by agro nets or any other woven /knitted  material to allow required sunlight, 
moisture and air to pass through the gaps . 
3.3 cover factor  
area covered by the yarn and fibre of the structure.  
3.4 bundle  
package of things wrapped together . 
4. MATERIALS  
4.1 HDPE Tapes  
Tapes shall be manufactured from HDPE granules, which shall be UV stabilized by adding suitable 
UV stabilizer. The width of the tape used in the fabric shall be 1.70 mm and linear density of the tape 
shall be 10 Tex ( 100 Denier).  As agreed to between the buyer and the se ller, coloured tapes shall be 
manufactured using colour master batch. The denier of HDPE tape used in the manufacture of shade 
nets shall be subjected to the following tolerances:  
4.1.1  The heat shrinkage of the tape at 60°C shall not exceed 5 per  cent and  shall not exceed 8 per  
cent at 95°C. For determining the shrinkage, the tape shall be subjected to the specified temperature 
for a period of 10 min in an air circulating oven and hot water bath respectively.  
4.2 Fabric  
The fabric used in the manufacture o f shade nets shall be woven or knitted and shall have a minimum 
width of 3 m. A tape of about 1.7 mm width having the name of the manufacture at the end shall be 
provided for proper identification of manufacture.  
  
 4.3 Colour  
The colour of the fabric shall preferably be green. However,  any other colour or a mixture of colour s 
may be supplied as per the agreement between the seller  and the buyer . The colour/shade shall be 
as specified in the contract or order. In case a sample has been agreed upon and sealed,  the supply 
shall be made in conformity with the sample in such respects.  
5. TYPES  
Based on the shading factor, the material is classified as follows:  
a) Type I, having shading factor of 50 per  cent;  
b) Type II, having shading factor of 75 per  cent; and  
c) Type III, having shading factor of 90 per  cent.  
 
6. REQUIREMENTS  
6.1 Dimensions and Mass  
The shade nets shall be made to the shade and dimensions as specified in the contract or order. The 
dimensions shall be determined by the method prescribed in TZS 44 . The following tolerance shall be 
permissible for length, width and mass (g/m2): 
Dimension  Tolerance (Per cent) 
Length    ±1 
Width    ±1 
Mass (g/m2)  ±3 
 
6.2 The shade net fabric shall confirm to the requirements specified in Table 1.  
Table 1 Requirements of  Shade Nets  Made from Tape Yarns  
 
S/N  
Characteristics   
Requirements   
Method of 
test Type I  Type II  Type III  
1 Mass, g/m2, Min 70 80 130 TZS 21  
2 Average breaking strength of 
shade fabric (Ravelled strip 
method, 325mm x 70mm) , 
Minimum  
a) Warp way  
b) Weft way  
 
 
 
180 
 180  
 
 
 
240 
 240  
 
 
 
270 
 270  
 
 
TZS 22  
3  Shading factor , per-cent 45 to  55 70 to 80  85 to 95 Annex A  
 
4  
Retention of breaking strength 
after UV exposure, N, Min  
85 per  cent of original actual value (fabric)  
 TZS 22  
5 Bursting pressure, kgf/cm2, Min 5 6 9 Annex B  
6 Colour fastness to artificial light  
(applicable for coloured shade 
nets only)  4 or better  4 or better  4 or better  TZS 40  
      
 
 
  
 7. PACKING AND MARKING  
7.1 Packing  
The tape yarn of the shade nets shall be packed in roll form in length of 50 m or as agreed  to between 
the buyer and seller . 
7.2 Marking  
7.2.1  The fabric roll shall be marked legibly by fixing a label bearing  the following information : - 
a) manufacturer's name or registered trade mark;  
b) type of shade nets and shading factor ;  
c) declared length and width of the shade nets;  
d) mass per unit area (g/ m2) of the shade nets;  
e) batch number and date of manufacture; and  
f) Country of origin.  
 
8. SAMPLING  
8.1 Lot  
All tape  yarns shade nets roll s/bundles  of same construction and type dispatched to a buyer against 
one dispatch note shall constitute a lot.  
8.2 Unless otherwise agreed upon between the buyer and the seller , the number of tape yarns shade 
nets depending on the size of the lot shall be selected  at random from the lot. The number of such 
shade nets shall be as given in Table 2.  
Table 2 Scale of Sampling  
S/N No. of rolls/bundles 
in Lot  Sample size  Sub-sample s ize Permissible number 
of Defective 
rolls/bundles  
1 Up to 50  3 2 0 
2 51 to 150  5 2 0 
3 151 to 300  8 3 1 
4 301 to 500  13 5 2 
5 501 and above  20 5 3 
 
9. NUMBER OF TEST SPECIMENS AND CRITERIA FOR CONFORMITY  
The number of test specimens and criteria for conformity shall be as given in Table 3. Any fabric roll 
failing to meet one or more of the corresponding requirements prescribes in 6.1 and Table 2 shall be 
considered as defective, only the Lot shall be accep ted if no defective roll/bundle is found.  
Table 3 Number of Test Specimens and Criteria for Conformity  
 
S/N  
Characteristic   
Number of rolls/bundles   
Criteria for Conformity  
 
1  
Material and manufacture, 
dimensions and mass   
According to col umn 3 of 
Table 2   
The defective rolls do 
not exceed the 
corresponding number in 
column 5 of Table 2  
 
2  
All other requirements   
According to col 4 of Table 2  All the test specimens 
shall pass tests  
  
 ANNEX A  
TEST METHOD FOR DETERMINING SHADING PERCEN TAGE OF SHADE NETS  
A-1 PRINCIPLE  
A sample of the shade nets is mounted in Shade -O-Meter tester and the amount of light transmitted 
or passed through the sample is measured with the help of Photo -synthetically Active Radiation 
(PAR) sensor, in W/m2. The relative me asurement of light transmitted with and without sample is 
considered for calculating the percentage of shade nets.  
A-2 SAMPLING  
A-2.1 Laboratory Sample  
For the laboratory sample take a swatch extending the full width of the product, of sufficient length 
along the selvage from each sample ro ll so that the requirements of A -2.2 can be met.  
A-2.2 Test Specimens  
From the laboratory sample, cut at least 10 samples each having  dimensions of 180 mm x 180 mm. 
Space the specimens along a diagonal on the unit of th e laboratory sample. Take no specimens 
nearer the selvage or edge of the shade nets. The selected test specimens shall not have any 
creases or folds.  
A-3 CONDITIONING  
Bring the specimens to moisture equilibrium in the atmosphere for testing shade nets (65 ± 5 per  cent 
relative humidity and 25 ± 2°C temperature). Equilibrium is considered to have been reached when 
the increase in the mass of the specimen, in successive weightings made at intervals of not less than 
2 h, does not exceed 0.1 per  cent of the mass of the specimen.  
A-4 APPARATUS  
The instrument used for measurement shall meet the geometric and spectral requirements. The 
schematic diagram of the apparatus is given in Fig. 1.  
 
All dimensions in millimetres  
Figure 1. SCHEMATIC DIAGRAM OF SHADE -O-METER  
 
A.4.1 The Shade -O-meter tester shall have a flat base with total approximate dimensions as given 
below  
Length x Diameter x Height = 970 mm x 350 mm x 325 mm.  
 
 A.4.2  Apparatus shall consist of a chamber in which arrangement for placement of light sourc e filters, 
sample holder and sensor shall be provided . The inside surface of chamber shall be painted with 
black paint and shall be highly reflecting throughout the visible spectrum . The light transmitted 
through the shade nets sample shall be measured by light sensors.  
A-5 TEST PROCEDURE  
A-5.1 Instrument shall be switched on and the reading for PAR without sample shall be taken on the 
sensor. This shall be recorded as T1. 
A-5.2 Shade nets sample (see C-2.2) shall be mounted in the slot of specimen holder. The reading of 
PAR measurement with sample shall be taken from the sensor. This shall be recorded as T2.  
NOTE: Test specimen shall be properly mounted in the specimen holder so that it shall not be very tight 
or very lose in the specimen holder.  
A-6 CALCULATION  
A-6.1 Shading percentage shall be calculated from the following formula:  
  Shading percentage =  𝑇1−𝑇2
𝑇1𝑋100 
  Where  
T1 = reading of transmitted light, in W/m2 (without sample); and  
  T2 = reading of transmitted light, in W/m2 (with sample).  
A-6.2 Calculate the arithmetic mean of the measured values of shading percentage of ten samples.  
  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
 ANNEX B  
DETERMINATION OF BURSTING STRENGTH AND BURSTING DISTENSION OF 
FABRICS  
DIAPHRAGM METHOD  
B-1 PRINCIPLE  
B-1.1 A specified area of the sample of fabric under test is clamped over an elastic diaphragm by 
means of a flat annular clamping ring, and an increasing fluid pressure is applied to the underside of 
the diaphragm until the specimen bursts.  The operating fluid ma y be either a liquid or a gas.  
B-2 SAMPLING  
B-2.1 Samples shall be selected so as to be representative of the lot.  
B-2.2 Samples drawn in accordance with the procedure laid down in the material specification or as 
agreed to between the buyer and the seller  shall be taken as representative of the lot.  
B-3 TEST SPECIMENS  
B-3.1 From the test sample cut out at least 10 test specimens each 250 x 250 mm or 75 x 75 mm in 
size, by  drawing one test specimen (see Note) from each of the pieces constituting the test sample; 
these shall constitute the test specimens.  
NOTE – More than one test specimen may be cut out of one or more sample pieces to make up for 10 
test specimens.  
B-3.2 The system of clamping used generally permits tests to be applied without cutting out 
specimens (which may be resorted to, if desired). The sample of fabric available may sometimes be in 
one or more pieces but it should be possible to test it at 10 places. The 10 test areas shall be so 
distributed as to be representative of the sample and avoiding selvedge, creased or wrinkled places, 
and other such non -representative  areas of the sample.  
B-4 ATMOSPHERIC CONDITIONS FOR CONDITIONING AND TESTING  
B-4.1 The conditioning and testing shall be carried out in standard atmosphere at 65  ± 2 per  cent 
relative humidity and 27 ± 2°C temperature.  
B-4.2 Prior to evaluation, the test specimens shall be conditioned to moisture equilibrium in the 
standard atmosphere ( see Note).  
NOTE: For guidance purposes, it may be noted that, the minimum time required to reach moisture 
equilibrium for the various types of textile materials having moisture regain less than 5 per  cent is about 
6 hours while the same for those having mo isture regain more than 5 per  cent is 24 hours.  
B-5 APPARATUS  
B-5.1 For T est Diameter  of 113 mm  
B-5.1.1 The bursting strength tester shall have a flat base plate of diameter at least 140 mm, covered 
by a flat diaphragm of rubber or similar material (of thickness not more than 1 mm). A central hole in 
the base plate shall allow a controlled increase in fluid pressure to be applied to the  underside of the 
diaphragm, so that the specimen bursts in 20 ± 3 seconds. The rate of flow of fluid through the hole in 
the base plate shall not vary more than ±20 per  cent throughout the test.  
B-5.1.2 A  clamping ring of internal diameter 113.00 ± 0.03 m m and of external diameter 140 mm 
(Min) shall be provided with a flat lower surface to hold the specimen firmly against the diaphragm at 
all points.   
 B-5.1.3  The lower face of the clamping ring may be lined with a thin layer of cork or other 
compressible ma terial suitable for the fabric under test; if the face is unlined, its inner edge (or inner 
periphery) shall have a radius of 0.5 mm.  
B-5.1.4 Means shall be provided for applying the clamping ring with sufficient pressure to prevent the 
fabric specimen from slipping during the test. The specimen shall not be damaged by the action of the 
clamping ring.  
B-5.1.5 Provision shall be made for indicating or recording the pressure under the diaphragm at any 
point in the range in which the machine is used to an a ccuracy of ± 0.25 mm.  
B-5.2 For Test Diameter of 30.5 mm  
B-5.2.1 All conditions shall be the same as B-5.1.1 to B-5.1.5 except that the diameter of the base 
plate shall be at least 55 mm and the internal and external diameters of the clamping ring shall be  
30.50 ± 0.05 mm and 55 mm ( Min); respectively.  
B-6 PROCEDURE  
B-6.1 Place the test specimen or the area of the sample to be tested over the diaphragm  so that it lies 
on a flat tensionless condition. Clamp it securely by means of clamping ring. Increase the pressure 
smoothly so that the bursting strength of the fabric is reached in 20 ± 3 seconds.  
B-6.1.1 Note the bursting strength and the bursting distension  of the spe cimen. If the specimen bursts 
close to edge of the clamping ring, record this fact and discard the reading, and carry out another test.  
B-6.1.2 Repeat the test with other test specimens or at other places on the test sample, as the case 
may be, to have at  least 10 acceptable measurements.  
B-6.2 Diaphragm Correction – With the same rate fluid flow as employed in the above test, distend 
the diaphragm, without the presence of a specimen, but with the clamping ring in position, and note 
the pressure required t o distend it by an amount equal to the average distension  of the specimens. 
The pressure is the “diaphragm correction”.  
B-7 CALCULATION  
B-7.1 Calculate the arithmetic mean of the measured values of bursting strength and from this 
subtracts  the diaphragm co rrection.  
B-7.2 Express the arithmetic mean of the bursting distension  of the specimens selected for the 
calculation of bursting pressure to the nearest 2 per  cent.  
B-8 TEST REPORT  
B-8.1 The test report shall include the following information:  
a) Mean bursting strength in kilogram force per square centimetre or kilo -newton per square 
metre  
b) Diaphragm correction;  
c) Mean bursting distension ; and  
d) The type and capacity of the machine, the range at which it was operated, and the test 
diameter of the speci men.