DRAFT UGANDA STANDARD  
  DUS 1679  
First Edition  
2017 -01-2017 
 
 
 Reference number  
DUS 1679: 2017  
© UNBS 2017   
  
Specification for polyvinylchloride (PVC) for its safe use in 
contact with food stuffs, pharmaceuticals and drinking water  
 DUS 1679: 2017  
ii © UNBS 2017  – All rights reserved  
 Compliance with this standard does not, of itself confer immunity from legal obligations  
A Uganda Standard does not purport to inc lude all necessary provisions of a contract. Users are 
responsible for its correct application  
© UNBS 2017   
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilised in any 
form or by any means, electronic o r mechanical, including photocopying and microfilm, without prior 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  
Ugand a 
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 1679: 2017  
© UNBS 2017  – All rights reserved  iii 
 Contents  Page 
Foreword  ................................ ................................ ................................ ................................ ............................  iv 
1 Scope  ................................ ................................ ................................ ................................ ......................  1 
2 Normative references  ................................ ................................ ................................ ............................  1 
3 Terms and defin itions  ................................ ................................ ................................ ...........................  1 
4 Requirements  ................................ ................................ ................................ ................................ .........  2 
4.1 Material  ................................ ................................ ................................ ................................ ...................  2 
4.2 Pigments and colora nts ................................ ................................ ................................ ........................  2 
4.3 Monomer content  ................................ ................................ ................................ ................................ .. 2 
4.4 Overall migration  ................................ ................................ ................................ ................................ ... 2 
4.5 Storage and control  ................................ ................................ ................................ ...............................  3 
4.5.1  Storage  ................................ ................................ ................................ ................................ ...................  3 
4.5.2  Good Manufacturing Practices (GMP)  ................................ ................................ ................................ . 3 
5 Packing and marking  ................................ ................................ ................................ ............................  3 
6 Sampling  ................................ ................................ ................................ ................................ ................  3 
Annex  A (normative)  Determination of vinyl chloride monomer in basic materials an d articles  .............  4 
A.1 General  ................................ ................................ ................................ ................................ ...................  4 
A.2 Reagents  ................................ ................................ ................................ ................................ ................  4 
A.3 Apparatus  ................................ ................................ ................................ ................................ ...............  4 
A.3.1  Gas-chromatograph  ................................ ................................ ................................ ..............................  4 
A.3.2  Flame ionization detector or other detectors mentioned in A 6.  ................................ ......................  4 
A.3.3  Gas-chromatographic Column  ................................ ................................ ................................ .............  4 
A.3.4  Sample vials or flasks fitted with silicon or butyl rubber septa  ................................ .......................  4 
A.3.5  Micro -syringes  ................................ ................................ ................................ ................................ ....... 5 
A.3.6  Gas-tight syringes for manual headspace sampling  ................................ ................................ .........  5 
A.3.7  Analytical Balance; accurate to 0.1  mg. ................................ ................................ ..............................  5 
A.4 Procedure  ................................ ................................ ................................ ................................ ...............  5 
A.4.1  Preparation of Concentrated Standard VC Solution at Approximately 2000 mg/kg  ......................  5 
A.4.2  Preparation of Dilute Standard VC Solution  ................................ ................................ .......................  5 
A.4.3  Preparation of Calibration Curve  ................................ ................................ ................................ .........  5 
A.5 Gas chromatographic determinations  ................................ ................................ ................................  6 
A.6 Calculation of the test results  ................................ ................................ ................................ ..............  7 
A.7 Confirmation of the VC level  ................................ ................................ ................................ ................  7 
A.8 Repeatability  ................................ ................................ ................................ ................................ ..........  7 
Annex  B (Normative)  Sampling of PVC and its copolymers  ................................ ................................ .........  8 
B.1 General  ................................ ................................ ................................ ................................ ...................  8 
B.2 Scale of sampling  ................................ ................................ ................................ ................................ .. 8 
B.3 Preparation of test samples  ................................ ................................ ................................ .................  9 
B.4 Number of tests  ................................ ................................ ................................ ................................ ..... 9 
B.5 Criteria for conformity ................................ ................................ ................................ ...........................  9 
 DUS 1679: 2017  
iv © UNBS 2017  – All rights reserved  
 Foreword  
Uganda National Bureau of Standards (UNBS) is a parastatal under the Ministry of T rade, Industry and 
Cooperatives established under Cap 327 , of the Laws of Uganda , as amended .  UNBS is mandated to co -
ordinate the elaboration of standards and is  
(a) a member of International Organisation for Standardisation (ISO) and  
(b) a contact point for th e WHO/FAO Codex Alimentarius Commission on Food Standards, and  
(c) the National Enquiry Point on TBT  Agreement  of the World Trade Organisation (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 wi dely 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 fo r this document is Technical Committee UNBS/TC 19, Packaging and 
Packaging products  
 DRAFT UGANDA STANDARD  DUS 1679: 2017  
 
© UNBS 2017  – All rights reserved  1 
 Specification for Polyvinyl chloride (PVC) for its safe use in 
contact with food stuffs, pharmaceuticals and drinking water  
1 Scope  
This Draft Uganda Sta ndard specifies t he requirements and methods of sampling and test for polyvinyl 
chloride (PVC) and its copolymers for the manufacture of plastic items used in contact with foodstuffs, 
pharmaceuticals and drinking water.  
2 Normative references  
The following referenced docum ents referred to in the text in such a way that some or all of their content 
constitutes requirements of this document. For dated references, only the edition cited applies. For undated 
references, the latest edition of the referenced document (including a ny amendments) applies.  
DUS 1667 , Positive list of constituents of polyvinyl chloride (PVC) and its copolymers in contact with food 
stuffs, pharmaceuticals and drinking water.  
US 1659 , Packaging materials for food contact use – General requirements  
US 1675 , Determination of overall migration of constituents of plastics materials and articles intended to come 
in contact with foodstuffs – Method of analysis  
3 Terms and definitions  
For the purposes of this standard, the following term and definition shall appl y. 
3.1  
Polyvinyl Chloride  
shall mean:  
a) the homopolymers of vinyl chloride;  
b) copolvmers containing at least 50 percent by mass of vinyl chloride with one or several of the 
following monomers:  
1) vinylidene chloride;  
2) acrylonitrile;  
3) styrene and substituted styre ne; 
4) butadiene;  
5) ethylene;  
6) propylene;  DUS 1679: 2017  
2 © UNB S 2017  – All rights reserved  
 7) divinyl benzene;  
8) vinyl acetate;  
9) maleic, fumaric, itaconic, crotonic, acrylic and methacrylic acids ( maximum limit of 8 percent by 
mass of all these monomers); and  
10) esters of maleic, itaconic, crotonic, acrylic and methac rylic acids with saturated monohydric 
aliphatic alcohols;  
c) mixtures of homopolymers of vinyl chloride with one or several of the copolymers indicated in (b); and  
d) mixtures of several copolymers indicated in (b).  
4 Requirements  
4.1 Material  
The material shall  comply with the threshold limits of the catalysts, polymerization inhibitors, emulsifying 
agents, suspension agents, chain -transfer agents, miscellaneous additives, auxiliary items, that is, 
plasticizers, stabilizers, and other additives, as prescribed in  DUS 1667 . 
As the foils are to be used in contact with food stuffs they shall be produced with rolling oils/ lubricants which 
do not contain substances which are injurious to health or have any deleterious effect on the flavour, odour or 
appearance of food  stuffs.  
4.2 Pigments and colorants  
In case the coloured material is used for food packaging applications, it shall comply with the list and limits of 
the pigments and colorants prescribed in US 1659  
4.3 Monomer content  
3.3.1  The vinyl chloride monomer con tent of PVC suspension resin used for the manufacture shall not 
exceed 5 ppm, when tested as prescribed in Annex A  
3.3.2  The vinyl chloride monomer content (VCM) in the PVC containers/film used for packaging shall not 
exceed 1 ppm, when tested as prescribe d in Annex A.  
3.3.3  The residual migration of VCM into foodstuffs being packed shall not exceed 10 ppm.  
4.4 Overall migration  
The material shall also comply with the overall migration limit as detailed below when tested by the method 
prescribed in US 1675  
In the case of liquid foodstuffs or of simulants, the limit shall be 60 mg/I, Max. However, the value of the overall 
migration limit shall be equal to 10 mg/cm2, Max, of the surface of the material or article in the following cases:  
a) Containers or articles which are similar to containers or which in any case may be filled to a capacity 
less than 250 ml provided it is possible to calculate the surface of contact with the foodstuff.  
b) Sheets, foils and other non -fillable articles for which ratio between the surf ace area of the material or 
article and the quantity of foodstuffs in contact may not be calculated.  DUS 1679: 2017  
© UNBS 2017  – All rights reserved  3 
 4.5 Storage and control  
4.5.1  Storage  
Plastics materials intended for food contact use shall be stored separately from other materials in closed, 
properly identified containers.  
4.5.2  Good Manufacturing Practices (GMP)  
GMP shall be maintained at all times and personnel shall be trained in GMP.  
5 Packing and marking  
5.1 The material shall be packed as agreed between the purchaser and the manufacturer/supplier , in a 
manner so as to ensure that the items do not become contaminated during storage.  
5.2 Each package shall be clearly marked with the name and type of the material, month and year of 
manufacture of the material, name of the manufacturer and manufacture r’s trade mark, if any.  
6 Sampling  
The method of preparing representative test samples of the material and the criteria for conformity shall be as 
prescribed in Annex B.  DUS 1679: 2017  
4 © UNB S 2017  – All rights reserved  
 Annex  A 
(normative)  
 
Determination of vinyl chloride monomer in basic materials and ar ticles  
A.1 General  
In this method the vinyl chloride monomer level in basic materials or articles is determined by means of gas 
chromatography using the 'headspace' method after dissolution or suspension of the sample in N, N-
dimethylacetamide  
A.2 Reagents  
A.1.1  Vinyl chloride  (VC) of purity greater than 99.5 %  
A.1.2  N, N-dimethylacetamide (DMA), free from any impurity with the same retention time as VC or as the 
internal standard (A I.3) under the conditions of the test.  
A.1.3  Diethyl ether or cis -z-butene , in DMA (A I.2) as the internal standard solution. These internal 
standards shall not contain any impurity with the same retention time as VC, under the conditions of the test.  
A.3 Apparatus  
A.3.1  Gas-chromatograph   
Fitted with au tomatic head space sample r or 'with facilities for manual sample injection.  
A.3.2  Flame ionization detector or other detectors mentioned in A 6.  
A.3.3  Gas-chromatographic Column   
The column shall permit the separation of peaks of air, or VC  and of the internal standard, if used. 
Furthermore, the combined A 2.2 and A 2.3 system shall allow the signal obtained with a solution containing 
0.02 mg VC /litre DMA or 0.02 mg VC/kg IMA to be equal to at least five times the background noise.  
A.3.4  Sample vials or flasks fitted with silicon o r butyl rubber septa  
When using manual sampling techniques the taking of a sample from the headspace with a syringe may 
cause a partial vacuum to form inside the vial or flask. Hence, for manual techniques where the vials are not 
pressurized before the sa mple is taken, the use of large vials is recommended  DUS 1679: 2017  
© UNBS 2017  – All rights reserved  5 
 A.3.5  Micro -syringes  
A.3.6  Gas-tight syringes for manual headspace sampling  
A.3.7  Analytical Balance; accurate to 0.1 mg.  
A.4 Procedure  
CAUTION  VC is a hazardous substance and a gas at ambient temperatur e, therefore, the preparation of  
solutions should be carried out in a well ventilated fume cupboard. Take all the necessary precautions to 
ensure that no VC or DMA is lost.  
NOTE 1  When employing manual sampling techniques an internal standard (A.1.3) shoul d be used.  
NOTE 2  When using an internal standard, the same solution shall be utilised throughout the procedure.  
A.4.1  Prepara tion of Concentrated Standard VC Solu tion at Appr oxim ately 2000  mg/kg  
Accurately weigh to the nearest 0.1 mg a suitable glass vess el and place in it a 50 ml quantity of DMA. 
Reweigh. Add to the DMA 0.1 g of VC in liquid or gas form, injecting it slowly on to the DMA. The VC may also 
be added by bubbling it into the DMA, provided that a device is used which shall prevent loss of DMA. Re-
weigh to the nearest 0·1 mg. Wait for two hours to allow equilibrium to be attained. Keep the standard solution 
in refrigerator . 
A.4.2 Preparation of Dilute Standard VC Solution  
Take a  weighed amount of concentrated standard solution of VC (A 3.1) and  dilute, to a known volume of a 
known weight, with DMA or with  internal standard solution (1. 3). The concentration of the resultant  dilute 
standard solution is expressed as mg/l or mg /kg respectively.  
A.4.3  Preparation of Calibration Curve  
NOTE  The curve sha ll comprise at least 7 pairs of points.  
A.4.3.1  The repeatability of the responses shall be lower than 0 .02 mg  VC/l or kg of DMA. The curve shall be 
calculated from these points by  the least squares technique, that is, the regression line shall be calculat ed 
using the following equation:  
0 1axay
 
where,  

2x)(2xny x)(xyn
1a
 
2 22
0
x)( xnxy) x)(()x y)((a
 
where  
y the height or area of peaks in any single determination,  DUS 1679: 2017  
6 © UNB S 2017  – All rights reserved  
 x the corresponding concentration on the regression line, and  
n number of deter minations carried out (n.≥ 14). 
A.4.3.2 The curve shall be linear, that is, the standard deviation, (s) of the differences between the measured 
responses (y 1) and the corresponding  value of the responses calc ulated from the regression line (z1) divided 
by the mean value (
_
y ) of all the measured responses shall not exceed 0.07.  
This shall be calculated from:  
07.0
ys
 
1n2_
yiy
s




 
where  
yi each individual measured response,  
Zi the corresponding value of the respo nse (yi) on the calculated regression line, and  
n ≥14. 
A.4.3.3  Prepare two series of at le ast 7 vials (A 3 .4). Add to each  vial volumes of dilute standard VC 
solution (A.4.2 ) and DMA ( A.2.3 ) or internal  standard solution in DMA (A.2.3) such that the final VC 
concentration of the duplicate solutions shall be approximately equal  to 0, 0.050, 0.075, 0.100, 0.125, 0.150, 
0.200 mg/l or mg/kg of DMA and  that all the vials contain the same quantity of  DMA that is to be used  under 
A.4.4. Seal the vials and proceed as described under A.4 .5. Construct a graph in whi ch the ordinate values 
show the areas (or  heights) of the VC peaks of the duplicate solutions or the ratio of these  areas, (or heights) 
to those of the relevant internal standard peaks and the  abscissa values show the VC concentrations of the 
duplicate sol utions.  
A.4.4 Repeat the procedure described unde r A.4.1 and A.4. 2 to obtain a  second diluted standard solution 
with a concentration  equal to 0.1 mg VC/l or 0.1 mg/kg of DMA or internal standard  solution. The average of 
two gas -chromatographic determi natio ns of  this solution shall not differ by more than 5 %  from the  
corresponding point of the calibration curve. If the difference is greater  than 5 % , reject a ll the solutions 
obtained in A.4.1, A.4.2, A.4. 3 and A.4. 4 and repeat the procedure from the beginni ng. 
A.4.5  Prepare two vials (A.3.4). Weigh into each vial not less than 200 mg, to the nearest 0.1 mg, of the 
sample obtained from a single material or article under investigation which has been reduced to small pieces. 
Try to ensure that an equal quantity  is weighed into each vial. Close the vial immediately. Add to each vial for 
each gram of the sample 10 ml or 10 g of DMA (A.2.3) or 10 ml or 10 g of internal standard solution (A.2.3). 
Seal the vials and proceed as described under A 5. 
A.5 Gas chromatogra phic determinations  
A.5.1  Agitate the vials avoiding contact between the contained liquid and the septum ( A.3.4 ) to obtain a 
solution or suspension of the samples of material or article ( A.4.5) as homogeneous as possible  
A.5.2  Put all the sealed vials (A.4.3, A.4.4 and A.4.5) in a water bath for 2 hours at 60 0C ±1 0 C to allow 
equilibrium to be attained. Agitate again if necessary  DUS 1679: 2017  
© UNBS 2017  – All rights reserved  7 
 A.5.3  Take a sample from the headspace in the vial. When utilising manual sampling techniques care shall 
be exercised in obt aining a reproducible sample (see  A.3.4), in particular the syringe shall be pre - warmed to 
the temperature of the sample. Measure the area (or height) of the peaks relating to the VC and to the internal 
standard, if used.  
A.5.4  Remove from the column (A. 3.3) excess DMA using an appropriate method as soon as peaks of DMA 
appear on the chromatogram.  
A.6 Calculation of the test results  
A.6.1  Find by interpolation on the curve, the unknown concentration of each of the two solutions of the 
sample taking accoun t of the internal standard solution if used. Calculate the amount of VC in each of the two 
samples of material or article under investigation by applying the following formula  
1000
MVCX 
 
where  
X concentration of VC in the sample of the materia l or article expressed in mg/kg,  
C concentration of VC in the vial containing the sample of material or article (see A.4.5) expressed in 
mg/l or mg/kg,  
V volume or mass of DMA in the vial containing the sample of material or article (see A.4.5) expressed 
in Litres or kg, and  
M amount of the sample of the material or article expressed in grams.  
A.6.2  The concentration of VC in the material and article under investigation expressed in mg/kg shall be 
the average of the two concentrations of V C (mg/kg) determin ed under A.6.1  provided that the repeatability 
criterion under A.8 is satisfied.  
A.7 Confirmation of the VC level  
A.7.1  In cases where the content of VC in materials and ar ticles as calculated under A.6.1  exceeds the 
maximum permissible amount the results obtained by the analysis of each of two samples (A.5.1 and A.6.1 ) 
shall be confirmed in one of three ways:  
a) by using at least one other column (A.3.3 ) having a stationary phase with a different polarity. This 
procedure should continue until a chromatogram  is obtained with no evidence of overlap of the VC 
and/or internal standard peaks with constituents of the sample of the material or article; or  
b) by using other detectors, namely, the micro -electrolytic conductivity detector; or  
c) by using mass -spectrometry. In this case, if molecular ions with parent masses (m/e) of 62 and 64 are 
found in the ratio of 3:1, it may be regarded with high probability as confirming the presence of VC. In 
case of doubt the total mass spectrum shall be checked.  
A.8 Repeatability  
The difference between the resu lts of two determinations (A.6.1 ) carried out simultaneously or in rapid 
succession on the same sample, by the same analyst, under the same conditions, shall not exceed 0.2 mg 
VC/kg of material or article.  DUS 1679: 2017  
8 © UNB S 2017  – All rights reserved  
 Annex  B 
(Normative)  
 
Sampling of PVC and its copolymers  
B.1 General  
B.1.1  In drawing, preparing, storing and handling samples, the following precautions and directions shall be 
observed.  
B.1.2  Samples shall not be taken in an ex posed place.  
B.1.3  The sampling instrument, wherever applicable, shall be made of stainless steel or any other suitable 
material on which the material shall have no action. The instrument shall be clean and dry.  
B.1.4  Precautions shall be taken to protect the samples, the material being sampled, the sampling 
instrument and the containers for samples from adventitious contamination.  
B.1.5  The samples shall be placed in a suitable, clean, dry, air -tight metal or glass containers on which the 
material has no a ction. The sample containers shall be of such a size that they are almost completely filled by 
the sample.  
B.1.6  Each sample container shall be sealed air -tight with a stopper after filling and marked with full details 
of sampling, such as the date of samp ling, the month and year of manufacture of the material, etc.  
B.1.7  Samples shall be stored in such a manner that the temperature of the material does not vary unduly 
from the normal temperature.  
B.2 Scale of sampling  
B.2.1  Lot - In a single consignment al l the packages of the same class,  same type, same form and 
belonging  to the same batch of manufacture  shall be grouped together to constitute  a lot. If a consignment is 
known  to consist of packages belonging to different batches of manufacture or  different  forms, the packages 
belonging to the same batch of manufacture  and same form shall be grouped together and each such group 
shall constitute a lot.  
The packages may consist of containers of PVC and its copolymers, rolls, films or vials.  
B.2.2  For ascertain ing the conformity of the material to the requirements of this specification, samples shall 
be tested from each lot separately. The number of packages to be sampled shall depend on the size of the lot 
and shall be in accordance with col 1 and 2 of Table 1.  
These packages shall be selected at random from the lot and  in order to ensure the randomness of selection, 
procedures given in  ISO 24153  may be followed.  DUS 1679: 2017  
© UNBS 2017  – All rights reserved  9 
  
Table B 1 — Scale of sampling  
Number of packages 
in the lot  Sample size  
Up to 15  2 
16 to 50  3 
51 to 100  4 
101 to 300  5 
301 to 500  6 
501 to 1000  8 
1001 and above  10 
 
NOTE  When the number of packages in the lot is less than three, all the packages shall be sampled.  
B.3 Preparation of test samples  
B.3.1  From each of the pack ages of material selected, small portions of material shall be drawn with the 
help of a suitable sampling instrument. The total quantity of material collected from each package shall be 
sufficient to test all the requirements given in 3 of the specificatio n. 
B.3.2  In the case of packages consisting of containers, vials, rolls or films, the number of items to be 
selected from a package for testing each of the requirements given in3 of the specification, shall be one.  
B.4 Number of tests  
Tests for determining  all the requirements given in clause 4 of the specification shall be carried out on the 
individual test samples.  
B.5 Criteria for conformity  
The lot shall be declared as conforming to the requirements of this specification if all the test results on 
individual samples meet the relevant specification requirements . 
 DUS 1679: 2017  
© UNBS 2017  – All rights reserved  11 
 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 C ertification 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 scheme operated by 
the Uganda National Bureau of Standards and in conjunction with the releva nt 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 under 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 terms and conditions of licensing may be obtained from the Director, Uganda 
National Burea u of Standards.  
 
 DUS 1679: 2017    
 
ICS 71.100.01  
Price based on nn pages  
© UNBS 2017 – All rights reserved