DRAFT UGANDA STANDARD  
  DUS 2394  
First Edition  
2021 -mm-dd 
 
 
 Reference number  
DUS 2394: 2021  
© UNB S 2021   
  
Rubber teat  (nipple)  for baby feeding bottle  — Specification  
 DUS 2394 : 2021  
ii © UNBS 2021  – 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 
respons ible for its correct application  
© UNBS  2021   
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 pr ior 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 41 4 333 2 50/1/2/3  
Fax: +256 41 4 286 123  
E-mail: info@unbs.go.ug  
Web: www.unbs.go.ug  DUS 2394:2021  
© UNBS 2021  – All rights reserved  iii 
 Contents  Page 
Foreword  ................................ ................................ ................................ ................................ .............................  v 
1 Scope  ................................ ................................ ................................ ................................ ......................  1 
2 Normative references  ................................ ................................ ................................ ............................  1 
3 Terms and definitions  ................................ ................................ ................................ ...........................  1 
4 Requirements  ................................ ................................ ................................ ................................ .........  1 
4.1 General requirements  ................................ ................................ ................................ ...........................  1 
4.2 Specific requirements  ................................ ................................ ................................ ...........................  2 
5 Packaging  ................................ ................................ ................................ ................................ ...............  2 
6 Labelling  ................................ ................................ ................................ ................................ .................  2 
7 Sampling  ................................ ................................ ................................ ................................ ................  3 
Annex  A (normative)  Deter mination of Acetone extractable matter from rubber teats  .............................  4 
A.1 Outline of the Method  ................................ ................................ ................................ ............................  4 
A.2 Procedure  ................................ ................................ ................................ ................................ ...............  4 
A.3 Calculation  ................................ ................................ ................................ ................................ .............  4 
Annex  B (Normative)  Determination of free sulphur from acetone extractable matter in rubber 
teats  ................................ ................................ ................................ ................................ ........................  5 
B.1 Outline of the Method  ................................ ................................ ................................ ............................  5 
B.1.1  Reagents  ................................ ................................ ................................ ................................ ................  5 
B.1.2  Procedure  ................................ ................................ ................................ ................................ ...............  5 
B.1.3  Calculation  ................................ ................................ ................................ ................................ .............  6 
Annex  C (Normative)  Change in physical properties  ................................ ................................ ....................  7 
C.1 Change in physical properties  ................................ ................................ ................................ .............  7 
C.2 Water extract  ................................ ................................ ................................ ................................ ..........  7 
Annex  D (Normative)  Determination of pH value of water extract  ................................ ...............................  8 
D.1 Outline of the Method  ................................ ................................ ................................ ............................  8 
D.1 Apparatus  ................................ ................................ ................................ ................................ ...............  8 
D.2 Procedure  ................................ ................................ ................................ ................................ ...............  8 
D.3 Report  ................................ ................................ ................................ ................................ .....................  8 
Annex  E (Normative)  Tension test  ................................ ................................ ................................ ...................  9 
E.1 Procedure  ................................ ................................ ................................ ...Error! Bookmark not defined.  
Annex  F (Normative)  Determination of tear resistance  ................................ ................................ ...............  10 
F.1 Apparatus  ................................ ................................ ................................ ................................ .............  10 
F.2 Test method  ................................ ................................ ................................ ................................ .........  10 
Annex  G (Normative)  Resistance to sudden temperature changes  ................................ ...........................  13 
G.1 Test method  ................................ ................................ ................................ ................................ .........  13 
Annex  H (Normative)  Determination of N -nitrosamines and N -nitrosatable content  ...............................  14 
H.1 Release -test liquid (saliva test solution)  ................................ ................................ ...........................  14 
H.2 Test conditions  ................................ ................................ ................................ ................................ .... 14 
H.3 Determining the release of N -nitrosamines and N -nitrosatable substances  ................................  14 
Annex  I (Normative)  Bottle adhesion test ................................ ................................ ................................ ..... 15 
I.1 Apparatus  ................................ ................................ ................................ ................................ .............  15 
I.2 Test method  ................................ ................................ ................................ ................................ .........  15 
Annex  J (Normative)  Sampl ing of rubber teats for feeding bottles  ................................ ...........................  16 
J.1 General Requirements of sampling  ................................ ................................ ................................ ... 16 DUS 2394 : 2021  
iv © UNBS 2021  – All rights reserved  
 J.2 Scale of sampling  ................................ ................................ ................................ ...............................  16 
J.3 Number of tests and criteria for conformity  ................................ ................................ ....................  17 
J.3.1 Workmanship and Finish  ................................ ................................ ................................ .......................  17 
Bibliograph y ................................ ................................ ................................ ................................ .....................  18 
 DUS 2394:2021  
© UNBS 2021  – All rights reserved  v 
 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 t he 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 O rganisation (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 key stakeholders 
including government, academia,  consumer groups, private sector and other interested parties.  
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.  
The committee responsible for this document is Technical Committee UNBS /TC 303, Plastics and related 
products   
 DRAFT UGANDA STANDARD  DUS 2394: 20 21 
 
© UNBS  2021  – All rights reserved  1 
 Rubber teat  (nipple) for baby  feeding bottl e — Specification  
1 Scope   
This Draft Uganda S tandard specifies requirements, sampli ng and test methods for rubber teat  (nipple)  for 
baby feeding bottle  
2 Normative references   
There are no normative references in this document.  
3 Terms and defini tions   
For the purposes of this document, the following terms and definitions apply.  
ISO and IEC maintain terminological databases for use in standardization at the following addresses:  
— ISO Online browsing platform: available at http://www.iso.org/obp  
3.1  
baby feeding bottle  
bottle fitted with a nipple/ teat for feeding babies  
3.2 
teat (nipple)  
rubber mouth -piece of a baby feeding bottle resembling the tip of a mammary gland  
3.3 
extractable mater  
organic and inorganic chemical species that can be rele ased from the surface of the teat (nipple)  
3.4 
axis 
the line between the center and the longi tudinal point of the rubber teat  
4 Requirements  
4.1 General requirements  
4.1.1  The teat shall be made from food grade rubber together with necessary compounding an d vulcanizing 
ingredients . The teat shall be free from grits, reclaimed rubber  or vulcanized waste.  
4.1.2 All ingredients used shall be free from harmful substances l iable to extraction by contact with liquid 
foods  or which may cause the development of un desirable odour, taste or discolouration .   
2 © UNBS 2021  – All rights reserved  
 4.1.3 Softeners, organic accele rators and antioxidants, if incorporated, shall not impart an undesirable 
odour or taste to the finished rubber teats. The following  accelerators are recommended:  
a) Dithiocarbamates, and  
b) Appropriate Derivatives of Mercaptobenz othiazole.  
4.1.4 The teats shall be transparent or translucent and shall be free from patches, blisters, porosity, sticky 
abrasions, stains, spots burrs/ flash, embedded foreign matter or any other  defects when e xamined visually.  
4.1.5 The shape and size of the rubber teats shall be appropriate for use in feeding babies  
4.2 Specific requirements  
Rubber teat  for baby feeding  bottle  shall conform to the specific requirements in Table 1  
Table 1 ─ Specific requirements for rubber teat  for baby feeding bottle  
SN Characteristic  Requirement  Test method  
1 Extractable mater, %, max  3 Annex A  
2 Free sulphur, %, max  by weight  0.2 Annex B  
3 Change in physical properties  No sign of deterioration such as 
tackiness, hardness, crackiness and 
discolouration  Annex C  
4 Colour, odour and turbidity  No impacting colour, odour or turbidity  
5 pH 7.0 ± 0.5  Annex D 
6 Percentage deformation under t ension , %, max  20 Annex E 
7 Tear resistance  No crack  or tear  Annex F 
8 Temperature  No crack  or tear  Annex G  
10 N-nitrosamines, mg/kg, max  0.01 Annex H  
 N-nitrosatable, mg/kg, max  0.1 
11 Bottle adhesion  No crack or tear, no leakage  Annex I  
5 Pack aging 
The rubber teat shall be packaged in suitable containers that gua rantee product integrity during transportation, 
storage and handling . 
6 Labelling  
Each teat or package or both shall be legibly marked with the following:  
a) name and physical address of manufacturer or trade -mark, if any ; 
b) name of product as, “bottle teats  (nipples )” 
c) type of rubber used  
d) instruction for use, hygienic care, disposal and caution/warnings  
e) number o f teats in each package;  DUS 2394: 2021  
© UNBS 2021  – All rights reserved  3 
 f) batch number  and 
g) month and year of manufacture.  
7 Sampling  
For the purpose of ascertaining the conformity of the rubber teats to this specification, the scale of sampling 
and criteria for conformity shal l be as prescribed in Annex J .  
4 © UNBS 2021  – All rights reserved  
 Annex  A 
(normative)  
 
Determination of Acetone extractable matter from rubber teats  
A.1 Outline of the Method  
A known quantity of the sample is weigh ed and wrapped in a filter paper, folded, so that the particles cannot 
become detached and find their way into the extraction flask. The sample is then placed in the siphon cup of 
the extraction apparatus and extracted for a period considered adequate for the separation  involved by 
heating on a water bath. The extracted matter in the flask is freed from  the solvent and its contents are dried 
at a constant temperature, cooled and weighed.  
A.2 Procedure  
A.2.1  Place a weighed specimen of approximately 2 g in a filter paper. If the speci men is in the form of a 
sheet, cut it with scissors into strips 3 to 5 mm in width. If the specimen may become tacky during extraction, 
take care that adjacent portions are separated by paper.  
A.2.2  Fold the paper so that it wi ll fit in the extraction cup and suspend the cup in a weighed extraction flask 
contai ning 50 to 75 ml ‘of acetone. ( Prior to weighing of the flask, it shall hav e been dried for 2 h at 70 ± 5°C 
and cooled in a desiccator to the temperature of the balance ) 
A.2.3 Extract the specimen continuously for 16 hours heating at such a rate that the time required to fill and 
empty t he siphon cup will be between 2.5 and 3.5 minutes. Carefully note all characteristics of the extracts, 
both when hot and cold.  
A.2.4  Evapo rate off the acetone over a steam bath, using a gentle current of filtered air to prevent b oiling. 
Remove the flask from the steam bath just prior to the disappearance of the last traces of solvent to prevent 
loss of extract.  
A.2.5  Continue the passage of  air through the flask for 10 minutes to remove the remaining solvent and  dry 
the flask for 2 h at 70 ± 5°C in an air -bath. Cool in a desiccator to the tempera ture of the balance and weigh  
A.3 Calculation  
Calculate the percentage of the acetone extract as follows:  
 
Where : 
a weight in g of extract, and  
b weight in g of specimen used . DUS 2394: 2021  
© UNBS 2021  – All rights reserved  5 
 Annex  B 
(Normative)  
 
Determination of free sulphur from acetone extr actable matter in rubber 
teats  
B.1 Outline of the Method  
Free sulphur in the acetone extract is determined by the acid digestion method. In this method, the sample  is 
treated with an oxidising acid such as nitric and an auxiliary agent such as bromine, at an elevated 
temperature. By this oxidation  sulphur is con verted to sulphate, in which form it is estimated gravimetrically.  
B.1.1  Reagents  
B.1.1.1  Bromine ─ saturated bromine water  
B.1.1.2  Nitric Acid  with a specific gravity 1.50  
B.1.1.3  Zinc n itric a cid S olution ─ Add 200 g of Zinc oxide to one litre of nitri c acid  with a specific gravity 
1.42. 
B.1.1.4  Potassium Chlorate Crystals  
B.1.1.5  Picric Acid - saturated solution.  
B.1.1.6  Barium Chloride Solution ─ 100 g/litre and  
B.1.1.7  Hydrochloric Acid  
B.1.2  Procedure  
B.1.2.1  Add to the flask containing the acetone extract, 10 ml of zinc -nitric acid solution and 2 to 3 ml of 
bromine and cover with a watch glass. Allow to stand near a steam plate for 30 minutes, then heat on the 
steam plate to a foamy syrup.  
B.1.2.2  Add 10 ml of nitric acid and heat on the hot plate with the cover removed until all br omine is 
expelled. Continue if o rganic  matter or carbon remains at this point, add a few millilitres  of nitric acid and a few 
crystals of potassium chlorate  and evapo rate at boiling. Repeat this operation until all carbon  is removed and 
the solution is clear, colourless, or light yellow.  
At this point either of the following methods may be used.  
B.1.2. 3 Method  A ─ Place the flask on an asbestos gauze and evaporate the mi xture to dryness over a 
burner. Then bake the mixtu re at the highest temperature of the burner until all nitrates are decomposed and 
no more nitrogen oxide fumes can be detected. The flask and its contents must be carefully annealed after 
this procedure by gradually decreasing the flame or by placing the f lask on successi vely cooler source of heat.  
B.1.2. 4 Method B ─ Evaporate the mixture, cool, add 10 ml of hydrochloric acid, and evaporate to 
dryness, avoiding spattering. Repeat this procedure once, or more, if oxides of nitrogen are still evolved .  
B.1.2. 5 Cool the flask, add 5 0 ml of hydrochloric acid (1: 6 ) .and digest hot until solution is as complete as 
possible. Filter while hot. Wash the filter and dilute the filtrate and washings  using distilled water  to about  300 
ml.   
6 © UNBS 2021  – All rights reserved  
 B.1.2.6  .Add 10  ml of saturated pi cric acid solution, heat to 90 ˚C, and precipitate  the su lphate by 
dropwise addition of barium chloride solution while stirring vigorously . Digest the precipitate overnig ht, 
preferably at 60 ˚C to 80 ˚C, usi ng a watch glass to cover the beaker.  
B.1.2.7  Filter the barium sulphate and - wash with distilled water un til the filtrate is colourless. Dry, 
incinerate, and finally ignite  the precipitate at 650 ˚C to 900°C to constant weight. Cool in a desic cator and 
weigh  
B.1.3  Calculation  
Calculate the percentage of sulphur as follows:  
 
Where:  
A weight i n g of barium sul phate and  
B weight in g of specimen used.  DUS 2394: 2021  
© UNBS 2021  – All rights reserved  7 
 Annex  C 
(Normative)  
 
Change in physical properties  
C.1 Change in physical properties  
C.1.1  Outline of the Method ─ Teats are autoclaved for a known time at consta nt temperature and the 
change in physical properties of teats, as examined visually, is reported  
C.1.2  Procedure ─ Take three teats and autoclave them in 250 ml of water for one hour at 120 ˚C ± 5˚C. 
Cool the autoclave to room tempera ture and keep the water  extract for further test in (C.2). Keep the teats in 
an air-oven maintained at 120 ˚C ± 2°C for one hour, and examine the teats after cooling to room temperature 
for any sign of deterioration such as tackiness, hardness, crackiness and discolouration.  
C.2 Water extract  
Examine the water  extract as obtained under C.1.2  for any colour, odour and turbidity imparted to the water.   
8 © UNBS 2021  – All rights reserved  
 Annex  D 
(Normative)  
 
Determination of pH value of water extract  
D.1 Outline of the Met hod 
The p H value of the water extract is determined electrometrically with the help of the glass electrode, by direct 
reading method.  
D.1 Apparatus  
D.1.1  Beaker ─ A glass beaker of sufficient size to accommodate the sample used  
D.1.2  Metallic Container ─ Made of stainless ste el or copper for boiling water  
D.1.3  pH Meter ─ Equipped with glass and calomel electrodes to read directly pH  having an accuracy of ± 
0.05 p H  
D.1.4  Watch Glass   
D.2 Procedure  
D.2.1  Boil the sample for 15 minutes in water and decant the extract into the container.  
D.2.2  Let the mixture cool to room temperature in an atmosphere free from chemical fumes which might 
contaminate the samples.  
D.2.3 Decant off any supernatant liquid. Place the electrodes in the sludge and rotate the beaker gently in 
altern ate direction until a constant p H value is obtained. Repeat the procedure on a second sample.  
NOTE 1  ─ To prevent contamination of the sample during boiling, a clean watch - glass may be used over the beaker.  
NOTE 2  ─ Standardize the p H meter with a reliable buffer in the pH range of the aqueous extract samples to be tested.  
NOTE 3  ─ The distilled water u sed in the test should be as pure as possible. The pH of the freshly boiled distilled water 
shall be 6.9 ± 7.1 
D.3 Report  
The report shall include the following:  
a) Prope r identification of the sample and  
b) Result obtained from the two ind ividual determination s and their average.  DUS 2394: 2021  
© UNBS 2021  – All rights reserved  9 
 Annex  E 
(Normative)  
 
Deformation under Tension  test 
E.1 Apparatus  
E.1.1  Cutting tools for preparing the sample.  
E.1.2  Tensile testing machine and clamping accessories.  
E.1.3  Measuring steel tape or meter  rule capable of measuring accurate ly to ±0.5mm.  
E.1.4  Timer accurate to ±1s.  
E.2 Procedure  
E.2.1  Cut out the rim of the teat and cut it open to form a band.  
E.2.2  Mark two reference lines 25mm apart in the centre of the band.  
E.2.3  Connect the band to a ten sile testing machine and stretch it up -to 75mm and hold for 10mins.  
E.2.4  Release the band and measure distanc e between the reference lines, l . 
E.3 Expression of results.  
Calculate the permanent deformation / elongation under tension expressed as a percenta ge of original length.  
 
  
10 © UNBS 2021  – All rights reserved  
 Annex  F 
(Normative)  
 
Determination o f tear resistance  
F.1 Apparatus  
F.1.1  Pressure testing machine  
F.1.2  Press bar, ported from nichrome high chrome steel, grade H13 (H13 high chr ome tool steel) or 
equivalent. It has a hardness of at least 50 Rockwell C, its shape and dimensions are shown in Figure 2, and 
it can be used with a pressure testing machine.  
F.1.3  The punching plate, made of plastic, has a hardness (70 ± 5) Shore D  
F.1.4  Tensile Strength Tester  
F.1.5  Equipment suitable for holding various parts of the rubber teat  
F.2 Test method  
F.2.1  Place the viewing part of the rubber tip on the punching plate  
F.2.2  Adjust the push rod connected to the pressure test apparatus so that t he center of the blade is Well, 
upright and perp endicular to the axis of the teat and about 15 mm to 20 mm from the top of the tip, measured 
along  the axis of the tip of the teat , see Figure F1. In case the cross section of the used part does not look 
circular Adjust the press bar to match the sharp flat part of the rubber teat head.  
F.2.3  Press the push rod onto the rubber tip at a rapid rate (10 ± 5) mm/min until a compression force (200 
± 10) N is achieved. This pressure is maintained for a period of tim e. (1 ± 0.5) s  
F.2.4  Inspect the puncture mark on th e teat head. If the rubber teat  is pierced through both sides of the wall, 
continue the test in the next item. Please do this test without having to continue with the next test.  
F.2.5  Fix the tip and base  of the rubber tip that was pierced through both sides of the wall by means of a 
fixing device  
F.2.6  Attach the device attached to the tensi le tester so that the tension is alig ned with the axis of the 
rubber nipple.  Adjust the tip  to align along the axis of the teat  with a clamping force (5 ± 2) N, then pull it with a 
fast speed (200 ±10) mm/min until a tensile (90 ± 5) N is maintained for a period of (10 ± 0.5) s.  
F.2.7  Examine the damage that has been caused by the hustle and bustle  DUS 2394: 2021  
© UNBS 2021  – All rights reserved  11 
  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Figu re 1 ─ The shape and size of the pressed bar  
 
 
 
12 © UNBS 2021  – All rights reserved  
 
Fig. 
Figure 2 ─ Loca tion of the puncture of the teat  head  DUS 2394: 2021  
© UNBS 2021  – All rights reserved  13 
 Annex  G 
(Normative)  
 
Resistance to sudden temperature changes  
G.1 Test method  
G.1.1  The rubber teats  are soaked in boiled distilled water for a period of time (10 ± 1) min without making 
contact with the container.  
G.1.2  The teat i s boiled and immediately imm ersed in distilled water at a temperature (5 ± 2) °C for (10 ± 1) 
min. 
G.1.3  Check to determine the damage caused to the rubber.   
14 © UNBS 2021  – All rights reserved  
 Annex  H 
(Normative)  
 
Determination of N -nitrosamines and N -nitrosatable content  
H.1 Release -test liquid (saliva test solution)  
To obtain the release -test liquid, dissolve 4. 2 g of sodium bicarbo nate (NaHCO 3.), 0.5 g of sodium chloride  
(NaCl), 0. 2 g of potassium carbonate (K 2CO 3,) and 30. 0 mg of sodium nitrite (NaN0 2) in one litre of  distilled 
water or water of equivalent quality. The solution must have a pH value of 9 0. 
H.2 Test conditions  
Samples of material obtained from an appropriate number of teats or soothers are immersed in the test  
release liquid for 24 hours a t a temperature of 40 ± 2 ° C.  
H.3 Determining the release of N -nitrosamines and N -nitrosatable substances  
H.3.1 The release of N -nitrosamines is determined in one aliquot of each solution obtained according to H.2. 
The N -nitrosamines are extracted from the aliquot with nitrosamine -free dichloromethane (DCM) and 
determined by gas chromatography.  
H.3.2  The releas e of N -nitrosatable substances is determined in another aliquot of the solution obtained 
according to H.2 The nitrosatable substances are converted into nitrosamines by acidification of the aliquot 
with hydrochloric acid. Subsequently the nitrosamines are extracted from the solution with DCM and 
determined by gas chromatography.  DUS 2394: 2021  
© UNBS 2021  – All rights reserved  15 
 Annex  I 
(Normative)  
 
Bottle adhesion test  
I.1 Apparatus  
I.1.1 Equipment for holding the baby feeding bottle so that t he horizontal plane is at an angle of 45° (see 
Figure F.I ). 
I.1.2 Equipment suitable for holding the rubber tip and can be connected to the tensile tester.  
I.1.3 Tensile testing machine  
I.2 Test method  
I.2.1 Assemble the rubber cap to the baby feeding bottle  filled with  a liquid to nominal capacity   
I.2.2 Hold the baby feeding bottle so that the horizontal plane is at an angle of 45° (see Figure F.I).  
I.2.3 Using the fixin g device secure  the loose tip of the rubber teat (10 ± 2) m m from the tip of the rubber 
teat. 
I.2.4 Connect the clamping device to the tensi le tester and gently pull the teat in line. at a rapid rate (200 ± 
10) mm/min until a tensile of (60 ± 5) N is obtaine d and hold for ( 10 ± 0.5) s  
I.2.5  Examine the damage caused  to the rubber teat and the leakage  from the baby feeding bottle.  
 
Figure FI  ─ Bottle adhesion test  
 
16 © UNBS 2021  – All rights reserved  
 Annex  J 
(Normative)  
 
Sampling of rubber teats for feeding bottles  
J.1 General Requirements of sampling  
J.1.1 Precauti ons shall be taken to protect the samples, the material being sampled and the containers for 
samples from adventitious contamination.  
J.1.2 The samples shall be placed in clean, dry and airtight glass or other suitable containers on which the 
material of the teats has no action.  
J.1.3 The sample containers shall be of such size that they are almost completely filled by the sample.  
J.1.4 Each sample container shall be sealed air tight and marked with full details of sampling, the date of 
sampling and the year of manufacture of teats.  
J.2 Scale of sampling  
J.2.1 Lot ─ All the rubber teats for feeding bottles of the same size and manufactured from the same raw 
materials under similar conditions of manufacture in one consignment shall constitute a lot.  
J.2.2 Samples shall be tested from each lot separately, for ascertaining conformity of a lot to the 
requirements of this specification. _  
J.2.3 The number of teats to be selected in the sample from a lot shall depend upon the size of the lot and 
shall be in a ccordance with Table J1.   
Table J1 ─ Scale of sampling and acceptance number  
SN No. of teats in the lot  No. of teats to be selected in 
the samples  Permissible No. of 
defective teats for 
workmanship and finish  Number of tests to 
be carried out for 
each of the other 
characteristics  
1 Up to 300  9 1 1 
2 301 to 1000  18 1 1 
3 1001 to 35 00 27 2 2 
4 3501 and above  45 3 3 
 
J.2.4   Although it is not possible to lay down any fixed rule as to how the samples are to be selected from 
the packages, it is desirable that the teats be drawn evenly from as many packages as possible. However, it is 
recommended that at least 10 percent of the packages should be selected and an equal number of teats 
drawn at random from each package selected to give the required number o f teats in accordance with col 3  of 
Table J1.  DUS 2394: 2021  
© UNBS 2021  – All rights reserved  17 
 J.3 Numb er of tests and criteria for conformity  
J.3.1 Workmanship and Finish  
J.3.1.1  All the teats selected in the sample shall be inspected for workmanship and finish in accordance 
with 4.1. A teat shall be considered to be defective, if it fails to satisfy the  requirements of workmanship and 
finish in any one or more respect.  
J.3.1.2  A lot  shall be considered as having satisfied the requirements of workmanship and finish, if the 
number of defective teats found as in J .3.1.1 does not exceed the applicable permi ssible number of defective 
teats.  
J.3.1.3  For determining the conformity of the lot to the requirements of: acetone extractable matter, free 
sulphur in acetone extract, change in physical properties , water extract (colour, odour, turbidity),  pH of water 
extract , tension test, tear resistance, temperature, N-nitrosamines, N -nitrosatable and bottle adhesion. The 
number of tests to be carried on a lot  per requirement , shall be in accordance with col 5 of Table J 1. For 
carrying out these tests, the rubber teats as  selected under col 3 of Table J 1 and found satisfactory for 
workmanship and finish shall be used. In case additional n umber of teats are required for these tests, they 
shall also be selected at random from the packages already used for drawing the samples.  
J.3.1.4  All the test results for the different characteristics shall satisfy the requirements of the 
specification i ndividually  
  
18 © UNBS 2021  – All rights reserved  
 Bibliography  
[1] IS 3565: 1966 , Specification for rubber teats for feeding bottles  
[2] TIS 969 -2562 , Rubber nipples for feeding bottles  
 WDUS 2394: 2021  
© UNBS  2021  – All rights reserved  19 
 Certification marking  
Products that conform to Uganda standards may be marked with Uganda National Bureau of Standards 
(UNBS) Certification Mark shown in the figure below.  
The use of the UNBS Certification Mark is governed by the Standards Act, and the Regulations made 
thereunder. This mark can be used only by those licensed under the certification mark schem e operated by 
the Uganda National Bureau of Standards and in conjunction with the relevant Uganda Standard. The 
presence of this mark on a product or in relation to a product is an assurance that the goods comply with the 
requirements of that standard unde r a system of supervision, control and testing in accordance with the 
certification mark scheme of the Uganda National Bureau of Standards. UNBS marked products are 
continually checked by UNBS for conformity to that standard.  
Further particulars of the te rms and conditions of licensing may be obtained from the Director, Uganda 
National Bureau of Standards.  
 
 WDUS 2394: 2021    
 
ICS nn.nnn.nn  
Price based on nn pages  
© UNBS 2021 – All rights reserved