UGANDA STANDARD  
  DUS 2266  
First Edition  
2020 -08-12 
 
 
 Reference number  
DUS 2266 : 2020  
© UNBS 2020   
  
Polymer film for damp -proofing and  waterproofing in buildings  
 Laminated (non -woven) products   
 DUS 2266 : 2020  
ii © UNBS 2020  – 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 
responsible for its correct application  
© UNBS 2020   
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, inclu ding 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  
Uganda  
Tel: +256 41 4 333 250/1/2/3  
Fax: +256 41 4 286 123  
E-mail: info@unbs.go.ug  
Web: www.unbs.go.ug  DUS  2266 :2020  
© UNBS 2020  – All rights reserved  iii 
 Contents  Page 
Foreword ................................ ................................ ................................ ................................ .................  v 
1 Scope  ................................ ................................ ................................ ................................ ..........  1 
2 Normative references  ................................ ................................ ................................ ..................  1 
3 Terms and definitions  ................................ ................................ ................................ .................  1 
4 Requirements  ................................ ................................ ................................ ...........................  2 
4.1 General  ................................ ................................ ................................ ................................ .......  2 
4.2 Composition  ................................ ................................ ................................ ...............................  2 
4.3 Measurement and dimensions  ................................ ................................ ................................ .... 3 
4.3.1  General  ................................ ................................ ................................ ................................ .......  3 
4.3.2  Thickness ................................ ................................ ................................ ................................ .... 3 
4.3.3  Mass per unit area ................................ ................................ ................................ .......................  3 
4.3.4  Width ................................ ................................ ................................ ................................ ...........  3 
4.3.5  Length  ................................ ................................ ................................ ................................ .........  3 
4.4 Mechanical and physical properties ................................ ................................ ............................  3 
4.5 Quality verification  ................................ ................................ ................................ ......................  4 
5 Packing and marking  ................................ ................................ ................................ ..................  4 
5.1 Packing  ................................ ................................ ................................ ................................ .......  4 
5.2 Marking  ................................ ................................ ................................ ................................ .......  4 
5.2.1  Packaged rolls of membrane  ................................ ..............................  Error! Bookmark not defined.  
5.2.2  Membrane  ................................ ................................ ................................ ................................ ... 5 
6 Inspection and methods of test ................................ ................................ ................................ ... 5 
6.1 Inspection  ................................ ................................ ................................ ................................ ... 5 
6.2 Test specimens and conditioning  ................................ ................................ ...............................  5 
6.3 Membrane width ................................ ................................ ................................ ..........................  5 
6.4 Membrane length  ................................ ................................ ................................ ........................  5 
6.5 Membrane thickness or mass per unit area  ................................ ................................ ................  5 
6.6 Tensile properties  ................................ ................................ ................................ .......................  6 
6.7 Puncture resistance (opti onal test)  ................................ ................................ .............................  6 
6.7.1  Apparatus  ................................ ................................ ................................ ................................ ... 6 
6.7.2  Test specimens  ................................ ................................ ................................ ...........................  6 
6.7.3  Procedure  ................................ ................................ ................................ ................................ ... 6 
6.7.4  Calculation  ................................ ................................ ................................ ................................ .. 6 
6.8 Tear strength ................................ ................................ ................................ ...............................  7 
6.9 Resistance to accelerate d aging  ................................ ................................ ................................ . 7 
6.9.1  Apparatus  ................................ ................................ ................................ ................................ ... 7 
6.9.2  Specimens  ................................ ................................ ................................ ................................ .. 7 
6.9.3  Procedure  ................................ ................................ ................................ ................................ ... 7 
6.10 Resistance to accelerated weathering  ................................ ................................ ........................  7 
6.10.1  Procedure  ................................ ................................ ................................ ................................ ... 7 
6.10.2  Testin g ................................ ................................ ................................ ................................ ........  7 
6.11 Water vapour transmission rate (WVT)  ................................ ................................ .......................  7 
6.11.1  Apparatus  ................................ ................................ ................................ ................................ ... 7 
6.11.2 Materials  ................................ ................................ ................................ ................................ ..... 8 
6.11.3  Test specimens  ................................ ................................ ................................ ...........................  8 
6.11.4  Procedure  ................................ ................................ ................................ ................................ ... 8 
6.11.5  Calc ulation  ................................ ................................ ................................ ................................ .. 9 
Annex  A (normative)  Notes to purchasers  ................................ ................................ ...........................  13 
Annex  B (informative)  The use and protection of polyolefin membrane  ................................ ..............  14 DUS 2266 : 2020  
iv © UNBS 2020  – All rights reserved  
 B.1 Function of the membrane ................................ ................................ ................................ .........  14 
B.2 Applications and installation of the membrane  ................................ ................................ .........  14 
B.3 Protection of the membrane  ................................ ................................ ................................ ...... 14 
Annex  C (informative)  Quality verification of polyolefin membrane and sampling plans  .....................  15 
C.1 Quality verification  ................................ ................................ ................................ ....................  15 
C.2 Sampling plans ................................ ................................ ................................ ..........................  15 
Bibliography  ................................ ................................ ................................ ................................ ..........  16 
 DUS  2266 :2020  
© UNBS 2020  – All rights reserved  v 
 Foreword  
Uganda National Bureau o f 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 the elaboration of standards and is  
(a) a member of International Organisa tion 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 Organisation (WTO).  
The work of preparing Uganda Standards is carried o ut 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 th e National Standards Council.  
The committee responsible for this document is Technical Committee UNBS /TC 03, [Building and 
Construction ], Subcommittee SC ##, [name of subcommittee] . 
This second/third/… edition cancels and replaces the first/second/… edition ( US nnn-n:yyyy ), which has been 
technically revised.  
US nnn consists of the following parts, under the general title Introductory element — Main element :  
  Part n: Part title  
  Part [n+1]: Part title  
  Part [n+2]: Part title  
 DUS 2266 : 2020  
vi © UNBS 2020  – All rights reserved  
  
 UGANDA STANDARD  DUS 2266 : 2020  
 
© UNBS 2020 – All rights reserved  1 
 Polymer film for damp -proof ing and waterproofing in buildings  
 Laminated (non -woven) products  
1 Scope   
This Standard  covers the requirements for non -woven, laminated, polyolefin membranes for use as a damp -
proofing material under concrete or clay roofing tiles . 
2 Normat ive references   
The following referenced documents 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 e dition of the referenced document (including any amendments) applies.  
ISO 4593, Plastics — Film and sheeting — Determination of thickness by mechanical scanning  
ISO 6383 -1, Plastics — Film and sheeting — Determination of tear resistance — Part 1: Trouser tear method  
ISO 527 -2, Plastics – Determination of tensile properties – Part 2: Test conditions for moulding and extrusion 
plastics  
DUS 2267 , Polymer film for damp -proofing and waterproofing in b uildings – Monofilament and co -extruded 
products.  
ISO 4892 -2, Plastics – Methods of exposure to laboratory light sources – Part 2:  Xenon -arc lamps.  
3 Terms and definitions   
For the purposes of this document, the terms and definitions given in DUS 2267  and the following apply.  
ISO and IEC maintain terminological databases for use in standardization at the following addresse s:  
— ISO Online browsing platform: available at http://www.iso.org/obp  
3.1 
laminated membrane  
polyolefin product consisting of spunbonded fibres formed  into a membrane, which is then laminated or coated 
with another polyolefin layer  
3.2 
spunbonded  
process  whereby polymer fibres are joined together under heat and pressure  DUS 2266 : 2020  
2 © UNBS 2020  – All rights reserved  
 4 Requirements  
4.1 General  
4.1.1  The membrane shall be either plain or embossed (textured), as specified (see annex A). The 
embossment of an embossed membrane shall be uniform over the ent ire area so patterned.  
4.1.2  The edges of a length of membrane shall be smooth, straight and parallel and the material shall be 
free from manufacturing imperfections and occluded dirt or other inadvertent contamination which might impair 
in-service perform ance.  
4.1.3  There shall be no cuts, tears, pinholes or any other defects which might impair in -service 
performance.  
NOTE  Further guidelines on the use and protection of polyolefin membrane are given in annex B.  
4.2 Composition  
4.2.1  The membrane material s hall be a virgin polyolefin compound and shall include suitable stabilizers in 
suitable proportions. It shall contain no rework material and no additives other than the following:  
a) Processing stabilizers, in accordance with the nature of the polymers as sho wn, namely  
1) for low -density polyethylene (LDPE) and polypropylene (PP): as specified in table 1; and  
2) for high -density polyethylene (HDPE), linear low -density polyethylene (LLDPE) and LLDPE 
blends: as specified in table 1.  
b) Pigment and service -life stabilizer s, as specified in table 1.  
NOTE  As part of the production process, edge -trim material from the product may be fed back into the same 
extruder.  
Table 1 — Required additives  
Additive  Content  
Polyethylenea  Polypropylenea  
% (mass fraction)  % (mass fractio n) 
Functional stabilizer  In accordance with the manufacturer’s recommendations  
a For 20 years minimum life expectancy.  
 
4.2.2  the membrane material may also incorporate evenly and thoroughly dispersed pigment.  
4.2.3  The laminating membrane shall be a vi rgin polyolefin and shall include suitable stabilizers in suitable 
proportions.  
4.2.4  The final laminated membrane product shall comply with the relevant stabilizer requirements given in 
table 1.  
4.2.5  There are no specific colour requirements for this typ e of product, unless specified by the purchaser 
(see annex A).  DUS  2266 : 2020  
© UNBS 2020  – All rights reserved  3 
 4.3 Measurement and dimensions  
4.3.1  General  
The functional property measurement used may be either thickness or mass per unit area, and the relevant 
requirements of 4.3.2 or 4.3.3 shall apply (see also annex A).  
4.3.2  Thickness  
4.3.2.1  Plain membrane (without embossment)  
When the membrane thickness is measured in accordance with 6.5, no individual determination shall be less 
than the relevant minimum value given in table 2.  
4.3.2.2  Embossed mem brane  
When the membrane is tested in accordance with 6.5,  
a) no individual determination of the gravimetric thickness shall be less than the relevant minimum value 
given in table 2; and  
b) each determined value of the mass per unit area of the membrane shall be at least equal to that on 
the appropriate line of figure 1 corresponding to the measured density of the membrane.  
4.3.3  Mass per unit area  
When the membrane is tested in accordance with 6.5, the membrane shall have a minimum mass per unit 
area of 100 g/m2 (gsm).  
4.3.4  Width  
4.3.4.1  The minimum width of the membrane shall be 1 200 mm (see also annex A).  
4.3.4.2  The actual width, when determined in accordance with 6.3, shall not be less than the minimum 
width of the membrane.  
4.3.5  Length  
The membrane shall b e supplied in rolls of single continuous length as specified (see annex A) and as stated 
on the label.  
When measured in accordance with 6.4, the length of the membrane in a roll shall not be less than the 
minimum length marked on the packaged roll (see als o 5.2.1.2(d)).  
4.4 Mechanical and physical properties  
4.4.1  When determined by the relevant test method given in column 3 of table 2, each of the properties 
listed in column 1 shall comply with the numerical requirements given in column 2, as applicable.  
4.4.2 Specimens subjected to accelerated weathering in accordance with 6.10 shall show no visible effects 
attributable to this treatment.  
4.4.3  The puncture resistance test is optional for this type of product, unless specified by the purchaser 
(see annex A ). DUS 2266 : 2020  
4 © UNBS 2020  – All rights reserved  
 Table 2 — Mechanical and physical properties  
Property  Requirement a Test method 
sub-clause  
Thicknessa, µm, min.  250 6.5 
Mass per unit areab, min. g/m2 100 6.5 
Tensile properties  
Breaking strength, N/mm of width, min.  
Elongation at break, %, min.   
2.16 
50  
6.6 
6.6 
Puncture resistance, N/mm of thickness, min.  29.0 6.7 
Tear strength, N/mm of thickness, min.  65.0 6.8 
Resistance to accelerated aging, % property retention, min.  
Breaking strength  
Elongation at break   
90 
90  
6.9 
6.9 
Resistance to accelerated weatheringa, % property retention, min.  
Breaking strength  
Elongation at break   
80 
80  
6.10 
6.10 
Water vapour transmission rate, g/m2 24 h, max.  12.2 6.11 
a The values shown in column 2 are instituted here on a trial basis, and may be revised  upwards if 
complaints regarding product performance are received.  
b See also annex A.  
 
4.5 Quality verification  
Quality verification of polyolefin membrane is given in annex C.  
5 Packing and marking  
5.1 Packing  
Each roll shall be completely packaged in a n acceptable material . Prepackages, contained in a correctly 
marked outer container which is likely to be opened in the retail for individ ual sale of the prepackages therein, 
shall each be marked with a quantity indication in accordance with this requirement unless exempted  
5.2 Marking  
5.2.1. 1 The label shall contain the foll owing information (as a minimum):  
a) the name, trade name or trademark of the manufacturer;  
b) the address of the manufacturer;  
c) recommended application of the membrane;  
d) the length of the membrane on the roll (see 4.3.5);  
e) the width of the membrane on the roll (se e 4.3.4);  DUS  2266 : 2020  
© UNBS 2020  – All rights reserved  5 
 f) the minimum thickness of the membrane on the roll (provided that no point on the surface of the 
membrane is thinner than the indicated minimum thickness);  
g) the net mass of the membrane.  
5.2.1.3  The length and width dimensions, and the mass value, shown on the label shall comply with the 
applicable tolerances or minimum requirements . 
5.2.2  Membrane  
The membrane of each roll shall be legibly and durably marked, at intervals of not more than 1 m along its 
length, with the following information:  
a) the trade na me or trademark of the manufacturer; and  
b) the minimum membrane thickness.  
6 Inspection and methods of test  
6.1 Inspection  
6.1.1  Inspect each roll of membrane taken for inspection, after unwrapping as necessary, for compliance 
with 5.1 and 5.2.  
6.1.2  Unroll the membrane in each roll for a length of at least 3 m and inspect the exposed surfaces and 
edges of the membrane for compliance with the relevant requirements of 4.1.  
6.2 Test specimens and conditioning  
6.2.1  Submit each roll taken for dimensional tests t o the tests given in 6.3, 6.4 and 6.5.  
6.2.2  Submit specimens from each roll taken for the remaining tests to the relevant test procedures.  
6.2.3  Condition all specimens used for the tests described in 6.5 to 6.8 and 6.11 for at least 16 h at a 
temperature  of 23 °C ± 2 °C and a relative humidity of (50 ± 4) %.  
Conduct the tests of 6.6 to 6.8 and 6.11 under these conditions.  
6.3 Membrane width  
6.3.1  Measure the width of the membrane, at an angle of 90° to its edge, at three locations at least 1 m 
apart in th e longitudinal direction of the membrane.  
6.3.2  Record, individually, the result of each measurement so taken, and check for compliance with 4.3.4.  
6.4 Membrane length  
Take one measurement of the length of the membrane along a line approximately parallel t o the longitudinal 
centre line of the membrane, and check for compliance with 4.3.5.  
6.5 Membrane thickness or mass per unit area  
Determine the thickness or mass per unit area of the membrane in accordance with ISO 4593 . 
Check for compliance with 4.3.2 or  4.3.3, as relevant.  DUS 2266 : 2020  
6 © UNBS 2020  – All rights reserved  
 6.6 Tensile properties  
Determine the breaking strength and elongation at break for the membrane in accordance with ISO 527 -2. 
Check for compliance with the relevant requirements of 4.4.  
6.7 Puncture resistance (optional test)  
6.7.1  Apparatus  
6.7.1.1  Tensile strength testing machine, as in 6.6, and designed to record applied forces in the range 0.5 
N to 225 N.  
6.7.1.2  Puncture apparatus (see figure 2), that consists of two light metal frames (with the lower frame 
sliding on the rods of the upper frame), and that has the following essential components:  
a) Puncture needle, that is a chromium -plated steel needle of length approximately 60 mm and of 
diameter 4.3 mm, with one end fixed to the lower surface of the upper member of the lower frame and 
the free portion tapering uniformly, for a distance of about 15 mm at an angle of 6°, to a point rounded 
to a radius of 0,57 mm; and  
b) Specimen holder assembly, that consists of two metal discs of diameter approximately 60 mm and 
thickness approximately 5 mm, each with a hole of diameter 25 mm in the centre and with the surface 
on one side suitably grooved to provide a grip for the specimen. The discs are held in position in the 
bottom of the upper frame by means of clamps.  
6.7.1.3  Cutting means, e.g. a s harp knife or razor blade, and a template or a sharp -edged circular die, 
suitable for cutting out test specimens.  
6.7.1.4  Micrometer, that is accurate to 0.002 5 mm and of a type that will not deform the membrane in the 
course of measurement.  
6.7.2  Test sp ecimens  
6.7.2.1  From each roll of membrane in the sample cut out five test specimens of diameter at least 50 mm, 
from locations spaced at least 500 mm apart in the longitudinal direction of the membrane.  
6.7.2.2  Condition the specimens (see 6.2) before tes ting them.  
6.7.3  Procedure  
6.7.3.1  Using the micrometer, measure the thickness in the centre of each specimen.  
6.7.3.2  Place and clamp centrally a test specimen between the discs of the puncture apparatus, secure 
the lugs of the apparatus in the jaws of th e tensile strength testing machine, and separate the jaws at a rate of 
traverse of 50 mm/min ± 15 mm/min until the specimen is punctured by the needle.  
6.7.3.3  Record the force required to puncture the test specimen.  
6.7.3.4  Repeat the test on the remainin g four specimens.  
6.7.4  Calculation  
6.7.4.1  Record individually the maximum force, in newtons, applied at the time of puncturing each 
specimen; then calculate the puncture resistance of each specimen, in newtons per millimetre of specimen 
thickness, and th e mean puncture resistance.  
6.7.4.2  Check for compliance with the relevant requirements of 4.4.  DUS  2266 : 2020  
© UNBS 2020  – All rights reserved  7 
 6.8 Tear strength  
Determine the tear strength of the membrane in accordance with ISO 6383 -1. 
6.9 Resistance to accelerated aging  
6.9.1  Apparatus  
6.9.1.1  Oven, t hat is an air -circulation oven maintained at 82 °C ± 1 °C.  
6.9.1.2  Cutting means, e.g. a sharp razor blade, for cutting out test specimens from the membrane.  
6.9.2  Specimens  
From each roll of membrane in the sample, cut out six specimens generally as for t he tensile tests (see 6.6) 
but sufficiently oversized to ensure that if shrinkage takes place during the heat treatment, a regular -sized test 
specimen can still be cut from each of the specimens afterwards.  
6.9.3  Procedure  
6.9.3.1  Place the specimens in th e oven at 82 °C (either laid on a mesh or grid shelf, or suspended if the 
shelves are solid) so that both sides of each specimen are reasonably accessible to the circulating air. Leave 
in the oven for 72 h, then remove and allow to condition in the test at mosphere (see 6.2) for at least 16 h.  
6.9.3.2  From each specimen cut out a test specimen as in 6.6, and determine the breaking strength and 
elongation at break as in 6.6.  
6.9.3.3  In the case of each property, calculate the mean result for the six test spec imens. Compare the 
results with those from the corresponding tests (see 6.6) on untreated specimens, and check for compliance 
with the relevant requirements of 4.4 for the percentage property retention of breaking strength and elongation 
at break.  
6.10 Resistance to accelerated weathering  
6.10.1  Procedure  
Using ISO 4892 -2 (exposure in a xenon -arc weathering apparatus), subject the requisite rectangular 
specimens of membrane (exposure panels) to radiation from the xenon -arc source, until the radiant -energy 
dose delivered to the specimens by the wavelength band 300 nm to 400 nm amounts to 380 MJ/m2. This 
dosage equates to an exposure time of 2 700 h.  
6.10.2  Testing  
6.10.2.1  Determine the tensile properties (see 6.6) and check for compliance with the relevant property 
retention requirements of 4.4.  
6.10.2.2  Ensure that the size and number of test specimens (exposure panels) are sufficient to enable the 
tensile properties to be determined.  
6.11 Water vapour transmission rate (WVT)  
6.11.1  Apparatus  
6.11.1.1  Test dishes. Shallow aluminium dishes of overall size appropriate to the analytical balance used 
(see 6.11.1.4), and that are round, square, or rectangular in shape. A dish has the general form shown in 
figure 3, and such that  DUS 2266 : 2020  
8 © UNBS 2020  – All rights reserved  
 a) it has a flange around the opening , equipped with a vertical rim either integral with the flange (figure 3(a)) 
or formed by an externally fitted aluminium ring (figure 3(b));  
b) the area of the opening of the dish, corresponding to the effective test area of the specimen (see figure 3), 
is between 3 020 mm2 and 3 220 mm2; 
c) the width of the flange is not more than 5 mm;  
d) the rim height does not exceed the specimen thickness by more than 5 mm; and  
e) the depth of the dish is the practical minimum necessary  
1. to hold enough desiccant for a test to be co mpleted before the total moisture uptake has reached 10 
% of the mass of the desiccant; and  
2. to accommodate this amount of desiccant when its surface is within 5 mm ± 1 mm of the lower 
surface of the specimen (see figure 3).  
NOTE  A dish depth of more than a bout 30 mm is unlikely to be required in practice.  
6.11.1.2  Template, the lower surface of which exactly matches the dish opening in shape and area, with a 
bevelled edge, and with the top terminating short of the rim of the dish, as shown in figure 3.  
6.11.1.3 Dish covers. Light aluminium covers for the dishes. These are required only if the dish/specimen 
assemblies are to be removed from the test enclosure for the mass measurement, so as to minimize changes 
in mass while the dishes are out of the test atmo sphere.  
6.11.1.4  Analytical balance, accurate to 0.000 5 g.  
6.11.1.5  Test enclosure. A conditioned room or humidity cabinet maintained at 38 °C ± 1 °C and (95 ± 5) 
% relative humidity, with the means of circulating the air continuously over the test specim en(s).  
6.11.2  Materials  
6.11.2.1  Desiccant. Anhydrous calcium chloride (granular, dust -free), freshly dried at 200 °C before use.  
6.11.2.2  Wax compound, that consists of 60 % microcrystalline wax in intimate blend with 40 % refined 
crystalline paraffin wax  (if required).  
NOTE  The wax compound is such that the change in its mass does not exceed 0.001 g when a sample with a 
surface area of 500 mm2 is exposed to the conditioned atmosphere of the test enclosure for 24 h.  
6.11.3  Test specimens  
6.11.3.1  From each  roll of membrane in the sample, cut out two test specimens so dimensioned that, 
when placed in position over the opening of a test dish, each specimen will peripherally overlap the flange by 
not less than one -half and not more than two -thirds of the width  of the flange.  
6.11.3.2  Condition the specimens (see 6.2) before testing them.  
6.11.4  Procedure  
6.11.4.1  Filling the test dish with desiccant, and mounting and sealing the specimen  
6.11.4.1.1  Carry out the operations in 6.11.4.1.2 to 6.11.4.1.5 as rapidly  as possible, so that the absorption 
of water vapour from the atmosphere is minimized. Ensure that the specimen is not damaged in the handling, 
that handling is minimized and confined to the outermost edges, and that the desiccant does not come into 
direct  contact with the specimen.  DUS  2266 : 2020  
© UNBS 2020  – All rights reserved  9 
 6.11.4.1.2  Fill each test dish with desiccant to the prescribed level (see 6.11.1.1(e)(2)).  
6.11.4.1.3  Place a specimen over the opening of the dish, and centre it carefully to ensure an even 
peripheral overlap of the flange by the specimen (i.e. circular specimen of diameter (150 + 2n) mm, where n is 
at least equal to the width of the cylinder flange of the test rig used).  
6.11.4.1.4  Place the template centrally over the specimen and run molten wax into the annular recess 
betwee n the bevelled edge of the template and the rim of the dish, until the resulting wax seal is level with the 
upper surface of the template (see figure 3).  
To facilitate subsequent removal of the template, apply a thin layer of petroleum jelly to the bevelle d edge 
before sealing, ensuring that none is put on the lower surface which will be in contact with the specimen. 
Careful, steady pouring should prevent the formation of bubbles in the wax seal. If any bubbles are formed, 
eliminate them by momentary applic ation of a small gas flame, but not so as to produce appreciable heating of 
the dish or template.  
6.11.4.1.5  When the wax has hardened, remove the template, inspect the assembly to ensure that the seal 
is suitable, and clear any wax from the outside of the  dish or retaining ring.  
NOTE  Any other suitable and effective sealing method may be used instead of the wax method.  
6.11.4.2  Determination of the rate of mass gain  
6.11.4 .2.1 Carry out the mass measurement of the dish/specimen assembly directly after comp letion of the 
sealing operation. If, as is preferable, the test enclosure is a conditioned room, carry out this mass 
measurement and all subsequent ones inside the room.  
6.11.4.2.2  Repeat the mass measurement of each assembly at suitable intervals of such duration that the 
test can be completed before the total water uptake by the desiccant has reached 10 % of the latter's initial 
mass (see 6.11.1.1(e)). Record the time of the mass measurement to a precision of approximately 1 % of the 
interval length (e.g.  to the nearest 70 s if mass measurements are made every 2 h). Carry out each mass 
measurement to an accuracy of 1 % of the change of mass between the two preceding mass measurements, 
or to 1 mg, whichever is the larger.  
If the assemblies are exposed in a cabinet from which they are removed for the mass measurement, ensure 
that all of them are out of the cabinet for the same period and under the same conditions at each successive 
mass measurement. On withdrawal from the cabinet, cover each assembly with its  lid and allow it to cool to 
the temperature of the room. After the mass measurement, remove the lid and immediately replace the 
assembly in the cabinet. Follow precisely the same routine and time schedule at each successive mass 
measurement. Wherever poss ible, keep the balance and the cabinet in the same room in which the 
atmosphere is controlled at constant temperature and humidity.  
6.11.4. 2.3 Plot the mass in milligrams of a dish/specimen assembly against the corresponding time in hours 
of its exposure t o the test atmosphere. Consider the rate of gain of mass constant, and conclude the test 
when six consecutive properly spaced points on the plot fall on a reasonably straight line.  
6.11.5  Calculation  
In the plot of mass against the corresponding exposure t ime for each specimen (see 6.11.4.2.3) draw a 
straight line as nearly as possible through those six points which represent the final, substantially constant 
rate of gain. From the graph determine the slope of the line, and calculate the  WVT rate for the sp ecimen as 
follows:  
W = 24 000 S/  A 
where  
W is the water vapour transmission rate, in grams per square metre (g/m2) per twenty -four hours;  DUS 2266 : 2020  
10 © UNBS 2020  – All rights reserved  
 S is the slope of the final linear portion of the graph, in milligrams per hour (mg/h);  
A is the exposed area of the s pecimen, in square millimetres (mm2). 
Calcula te, and record to the nearest 0. 1, the mean of all the WVT rates for the sample. Record this as the 
water vapour transmission rate of the membrane and check for compliance with the relevant requirements of 
4.4. 
 
NOTE  The general relationship between m, p and c is expressed by the straight -line equation  
m = kcp  
where  
m is the mass per unit area, in kilograms per square metre (kg/m2); 
k is the numerical constant 0.001;  
c is the gravimetrical thickness, in microns (μm). In this graph the lines are plots of the equation, 
with c = 375 μm, c = 325 μm and c = 215 μm, respectively;  
p is the sheet density, in grams per cubic centimetre (g/cm3). 
Figure 1 — Relationship between the mass per unit area and the density of embo ssed membrane for 
minimum gravimetric thicknesses of 375 μm, 325 μm and 215 μm A  DUS  2266 : 2020  
© UNBS 2020  – All rights reserved  11 
 
 
A – Lugs for insertion in jaws of tensile strength testing machine  
B – Puncture needle  
C – Specimen holder discs  
D – Specimen  
E – Clamping screws  
Figure 2 — Puncture apparat us  
 
 DUS 2266 : 2020  
12 © UNBS 2020  – All rights reserved  
 
 
 DUS  2266 : 2020  
© UNBS 2020  – All rights reserved  13 
 Annex  A 
(normative)  
 
Notes to purchasers   
The following requirements shall be specified in tender invitations and in each order or contract:  
a) whether the membrane shall be plain or embossed (see 4.1.1);  
b) the colour of the membrane, if required (see 4.2.5);  
c) the thickness or gsm, if it is to exceed the minimum value (see 4.3.1 and table 2);  
d) the width of the membrane, if it is to exceed the minimum value (see 4.3.4);  
e) the length of the membrane on a roll, if it is to exceed the minimum value (see 4.3.5);  
f) whether a puncture test is required (see 4.4.3).  DUS 2266 : 2020  
14 © UNBS 2020  – All rights reserved  
 Annex  B 
(informative)  
 
The use and protection of polyolefin membrane   
B.1 Function of the membrane  
The function of the membrane is to prevent the passage of  water or moisture from an external source into a 
structure, or from one part of the structure to another part.  
B.2 Applications and installation of the membrane  
Recommendations and directions regarding the applications and installation of the membrane are  provided in 
SANS 10021 . 
B.3 Protection of the membrane  
Because the effects of weathering can reduce the service life of the membrane, protection against exposure is 
required.  
Protection is also required against traffic, particularly on accessible roofs. S uch protection may be in the form 
of masonry, concrete, tiles or similar covering, and shall be provided as soon as the membrane is installed.  DUS  2266 : 2020  
© UNBS 2020  – All rights reserved  15 
 Annex  C 
(informative)  
 
Quality verification of polyolefin membrane and sampling plans   
C.1 Quality verification  
When a purchaser requires ongoing verification of the quality of polyolefin membrane, it is suggested that, 
instead of concentrating solely on evaluation of the final product, he also direct his attention to the 
manufacturer’s quality system. In this connec tion it should be noted that ISO 9001  covers the provision of an 
integrated quality management system.  
C.2 Sampling plans  
If no information about the implementation of quality control or testing during manufacture is available to help 
in assessing the qua lity of a lot, and a purchaser wishes to establish by inspection and testing of samples of 
the final product whether a lot of the polyolefin film produced to this specification complies with its 
requirements, suitable sampling plans can be found in SANS 28 59-1 for General Inspection Level II  
NOTE  For the purposes of this Standard , the following AQL (acceptance quality limit).values can be used:  
a) for thickness, AQL = 2,5;  
b) for width and length, AQL = 4;  
c) for the rest of the test, AQL = 4.  DUS 2266 : 2020  
16 © UNBS 2020  – All rights reserved  
 Bibliography  
[1] SANS 952 -2:2016 , Polymer film for damp -proofing and waterproofing in buildings  Part 2: Laminated 
(non-woven) products  
[2] SANS 2859 -1:2004, Sampling procedures for inspection by attributes 
  Part 1: Sampling schemes 
indexed by acceptance quality limit (AQL) for lot -by-lot inspection  
[3] SANS 10021:2012, The waterproofing of buildings (including damp -proofing and vapour barrier 
installation)  
 DUS 2266 : 2020  
© UNBS 2020 – All rights reserved  17 
 Certification marking  
Products that conform to Uganda standards may be marked with Uganda National Bureau of Standards 
(UNBS) Cer tification 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 scheme operated by 
the Ugand a 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 under a system of supervisi on, 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 l icensing may be obtained from the Director, Uganda 
National Bureau of Standards.  
 
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