UGANDA STANDARD  
  DUS 2265  
First Edition  
2020 -mm-dd 
 
 
 Reference number  
DUS 2265 : 2020 
© UNBS 2020   
  
Bitumen felts for water -proofing and damp -proofing  
Specification  
 
 DUS 2265 : 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, including photocopying and microfilm, wi thout 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 2 50/1/2/3  
Fax: +256 41 4 286 123  
E-mail: info@unbs.go.ug  
Web: www.unbs.go.ug  DUS 2265 :2020  
© UNBS 2020  – All rights reserved  iii 
 Contents  Page 
Foreword ................................ ................................ ................................ ................................ .................  v 
1 Scope  ................................ ................................ ................................ ................................ ..........  1 
2 Normative references  ................................ ................................ ................................ ..................  1 
3 Terms and definitions  ................................ ................................ ................................ .................  1 
4 Classification  ................................ ................................ ................................ ............................  1 
5 Materials  ................................ ................................ ................................ ................................ ..... 2 
5.1 Base fabrics  ................................ ................................ ................................ ................................  2 
5.1.1  Fibre-base felt  ................................ ................................ ................................ .............................  2 
5.1.2  Hessian Base Fibre  ................................ ................................ ................................ .....................  2 
5.2 Bituminous Saturate  ................................ ................................ ................................ ...................  2 
5.2.1 Composition  ................................ ................................ ................................ ...............................  2 
5.2.2  Weight  ................................ ................................ ................................ ................................ .........  2 
5.3 Bituminous Coatant  ................................ ................................ ................................ ....................  2 
5.3.1  Compos ition  ................................ ................................ ................................ ...............................  2 
5.3.2  Bituminous coatant ................................ ................................ ................................ .....................  3 
5.3.3  Weight  ................................ ................................ ................................ ................................ .........  3 
5.4 Mineral Powder f or Dusting ................................ ................................ ................................ .........  3 
5.4.1  Composition  ................................ ................................ ................................ ...............................  3 
5.4.2  Weight  ................................ ................................ ................................ ................................ .........  3 
6 Manufacture  ................................ ................................ ................................ ................................  3 
7 Dimensions  ................................ ................................ ................................ ................................ . 4 
8 Other requirements of bitumen felts  ................................ ................................ ...........................  4 
9 Tests  ................................ ................................ ................................ ................................ ...........  5 
9.1 Breaking strength test  ................................ ................................ ................................ ................  5 
9.1.1  Apparatus  ................................ ................................ ................................ ................................ ... 6 
9.1.2  Procedure  ................................ ................................ ................................ ................................ ... 6 
9.1.3  Reporting of the result  ................................ ................................ ................................ ................  6 
9.2 Pliability  ................................ ................................ ................................ ................................ ...... 6 
9.2.1  Apparatus  ................................ ................................ ................................ ................................ ... 6 
9.2.2  Procedure  ................................ ................................ ................................ ................................ ... 6 
9.2.3  Reporting  ................................ ................................ ................................ ................................ .... 7 
9.3 Storage sticking property  ................................ ................................ ................................ ...........  7 
9.3.1  Apparatus  ................................ ................................ ................................ ................................ ... 7 
9.3.2  Procedure  ................................ ................................ ................................ ................................ ... 7 
9.3.3  Reporting  ................................ ................................ ................................ ................................ .... 7 
9.4 Pressure head test  ................................ ................................ ................................ ......................  7 
9.4.1  Apparatus  ................................ ................................ ................................ ................................ ... 7 
9.4.2  Procedure  ................................ ................................ ................................ ................................ ... 8 
9.4.3  Reporting  ................................ ................................ ................................ ................................ .... 8 
9.5 Heat resistance property  ................................ ................................ ................................ .............  8 
9.5.1  Apparatus  ................................ ................................ ................................ ................................ ... 8 
9.5.2  Procedure  ................................ ................................ ................................ ................................ ... 8 
9.5.3  Reporting  ................................ ................................ ................................ ................................ .... 9 
9.6 Water absorption test ................................ ................................ ................................ ..................  9 
9.6.1  Apparatus  ................................ ................................ ................................ ................................ ... 9 
9.6.2  Procedure  ................................ ................................ ................................ ................................ ... 9 
9.6.3  Calculation  ................................ ................................ ................................ ................................ .. 9 
9.6.4  Reporting  ................................ ................................ ................................ ................................ .... 9 DUS 2265 : 2020  
iv © UNBS 2020  – All rights reserved  
 10 Sampling and criteria of conformity  ................................ ................................ ..........................  11 
10.1 Sampling  ................................ ................................ ................................ ................................ ... 11 
10.1.1  Lot ................................ ................................ ................................ ................................ .............  11 
10.1.4  Criteria for Conformity ................................ ................................ ................................ ...............  12 
11 Packing and marking  ................................ ................................ ................................ .................  12 
11.1 Packing ................................ ................................ ................................ ................................ ...... 12 
11.2 Marking ................................ ................................ ................................ ................................ ...... 12 
Bibliography  ................................ ................................ ................................ ................................ ..........  14 
 DUS 2265 :2020  
© UNBS 2020  – All rights reserved  v 
 Foreword  
Uganda National Bureau of Standards (UN BS) 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 Organisation for Standa rdisation (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 out through Tech nical 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 Standard s 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 Stan dards Council.  
The committee responsible for this document is Technical Committee UNBS /TC 03, [Building and 
Construction ], Subcommittee SC . 
This second/third/… edition cancels and replaces the first/second/… edition ( US nnn-n:yyyy ), whi ch 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 2265 : 2020  
vi © UNBS 2020  – All rights reserved  
  
 UGANDA STANDARD  DUS 2265 : 2020  
 
© UNBS 2020  – All rights reserved  1 
 Bitumen felts for water -proofing and damp -proofing  
Specification  
1 Scope   
This stand ard covers the requirements for saturated bitumen felts (underlay) and self -finished  bitumen felts 
used for water -proofing and damp -proofing.  
2 Normative references   
The following referenced documents referred t o 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 any amendments) applies.  
ASTM D5, Standard Test Method for Penetration of Bituminous Materials   
ASTM D36 M, Standard test method for softening point of bitumen  (ring-and-ball apparatus)  
FDEAS 982 -1, Bitumen and Bituminous binders – Part 1: Penetration grade bitumen -- Specifications  
3 Terms and definitions   
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 
waterproofing  
action to prevent the passage o f water from one plane to another  
4 Classification  
4.1 Bitumen felts shall be classified as given in 4.1.1 and 4.1.2 depending upo n the type of base used in 
their manufacture and the uses to which the felts are suited.  
4.1.1  Fibre Base  
Type I - Saturated f elt for underlay   
Type II - Self finished fel t (for waterproofing)   
4.1.2 Hessian  Base 
Type  III - [Self-finished felt (for waterproofing)  - Grade 1)  
[Self-finished felt (for damp -proofing)  - Grade 2)   DUS 2265 : 2020  
2 © UNBS 2020  – All rights reserved  
 5 Materials  
5.1 Base fabrics  
5.1.1 Fibre -base felt  
The base fabric for fibre -base felts shall consist of a suitable blend of vegetable and/or animal fibres. The 
weight of ash on incineration of the fabric shall not exceed 10 percent of its original weight  
5.1.2 Hessian Base Fibre  
The fabric shall conform to  Type II  hessian  
5.2 Bituminous Saturate  
5.2.1 Composition  
The saturate  used in the case of all types of felt shall conform to FDEAS 982 -1 with a penetration of not less 
than 80 at 25°C (see ASTM D5  ). 
5.2.2 Weight  
The weight of the saturate  shall be not l ess than 110 percent of the weight of the untreated felt for fibre -base 
felts and not less than 60 percent  of the weight of the untreated fabric for hessian  base fel ts subject to the 
minimum weigh t given  in Table 1 . 
5.3 Bituminous Coatant  
5.3.1 Composition  
a) The bitu minous coatant used for Types 2 and 3 felts shall consist of bitumen  conforming to industrial 
bitumen , with or without  admixture of bitumen conforming to  FDEAS 982 -1 and inert and water 
insoluble  fine mineral filler which shall pass  100 percen t through ISO-micron Sieve  and 95 percent 
through 75 micron Sieve  or inert and  water insoluble fibrous mineral filler.  
b) The inert fil ler shall not exceed 42 percent by weight of the coatant, subject to the  minimum weight 
specified in Table 1  for coatant.  
Table 1 Minimum Weight of Bitumen Felt (in kg) 
SI/No.  Type of f elt For 10 m2 
Untreated 
Base (see 
Note 1)  Saturant  Coatant  Bitumen 
content  Total weight of the finished 
bitumen felt in dry 
Condition with Mica, 
Dusting Powder, Min (see 
Notes 2 and 3)  
a Fibre b ase      
 Type 1 u nderlay  4.0 3.6 - 3.6 7.6 
 Type 2 self -finished  felt 5.0 4.5 12.9 12.0 22.6 
b Hessian b ase      
 Type 3 self -finished  felt 
Grade 1  2.3 1.8 17.7 12.1 23.0 
 Type 3 self -finished  felt 2.3 1.8 31.8 20.2 37.1 DUS 2265 : 2020  
© UNBS 2020  – All rights reserved  3 
 Grade 2  
Notes  
1 The weight of  the untreated base shall be taken as in dry  condition f or f ibre base f elts, In the case of  hessian base the weight of  untreat ed base shall 
conf orm to IS 2818 ( Part 2 ) : 1971.  
2 Include allowance f or 1.2 kg minimum mica dusting powder in dry  condition ex cept f or Ty pe 1,  
3 When other ty pe of  mineral powders are used, the weights shown in the last column shall be changed on the basis of  5.4.2, 
 
5.3.2 Bituminous coatant  
The bituminous coatant shall have a softening point of not less than 105°C when  measure d by the Ring and 
Ball method  (see ASTM D36 M ) and a penetration of not  less than 7 at 25° C (see ASTM D5 ). The coatant 
shall b e designed so that the finished felts comply with high temperature storage test  and the low - 
temperature pliability test.  
5.3.3 Weight 
The weight of th e coatant shall comply with the minimum weights specified in Table 1 for Type 2  and Type 3 
felts.  
5.4 Mineral Powder for Dusting  
5.4.1 Composition  
The mineral powder shall be powdered mineral matter, for example, mica, talc or slate, p assing through 600 -
micron.  
5.4.2 Weight  
The weight of the dusting powder incorporated shall be as follows:  
a) Mica powder – 1.2 to 2 kg/10 m2 
b) Talc powder – 1.5 kg to 2.25 kg/10 m2 
c) Slate powder – 1.5 kg to 2.25 kg/10 m2 
6 Manufacture  
6.1 The base fabric, fib re or hessian, after t he removal of the major portion of the inherent moisture, shall 
be saturated by immersion in the bitumen maintained in a molted condition and the surplus saturant shall be 
removed. The manufacture of the underlay, that is, Type 1 felt,  is complete at this stage.  
6.2 The base fabric shall be thoroughly and uniformly saturated.  
6.3 For the manufacture of self -finished felts, the saturated felt shall be treated by passing through the 
bituminous coatant material. The coatant shall be unifor mly applied. The resultant coated felts shall be given a 
superficial application of fine mineral powder.  
6.4 The weights of the ingredients of bitumen felts for 10 m2 shall be not less than those specified in Table 
1 during process.  
6.5 The finished materi al shall be free from visible external defects, such as holes, oil patches, ragged or 
untrue edges, breaks, cracks, tears, protuberances and indentations.  DUS 2265 : 2020  
4 © UNBS 2020  – All rights reserved  
 7 Dimensions  
Unless otherwise specified, bitumen felts shall be supplied in width s of 900 mm or 1000 mm and in lengths of 
10 m or 20 m with a tolerance of 30 mm 
8 Other requirements of bitumen felts  
8.1 Bitumen felts shall be subjected to the following tests, in addition to bitumen content test as per 8.2, and 
shall conform to the requirements given in T able 2. Sample  shall be  cut as explained in Fig. 1  
Table 2  Test requirement  
Type  Test  References to  
Type 1 Underlay test  Breaking strength  9.1 
 Pliability test  9.2 
Type 2 and  Breaking strength test  9.1 
Type 3 , All grades  Pliability test  9.2 
 Storage sticking test  9.3 
 Pressure head test  9.4 
 Heat resistance test  9.5 
 Water absorption test  9.6 
Notes  
1 Diameter of  Mandrel f or pliability  shall be as f ollows:  
Ty pe 1  50.0 mm  
Ty pe 2  50.0 mm  
Ty pe 3, Grade 2  50.0 mm  
Ty pe 3, Grade 2  75.0 mm  
2 The tests sha ll be carried ou t not earlier than two day s f rom the date of  manuf acture. 
 
8.2 Total Bitumen Content . The minimum weight of bitumen in the bitumen felts, when determined in 
accordance with clause 9.7  shall conform to the values given in col 6 of Table1.  
 
A, B-Breaking Strength  C, D-Pliability   E-Storage Sticking  
F-Heat Resistance  G-Pressure Head   H-Water Absorption  K-Binder Content  DUS 2265 : 2020  
© UNBS 2020  – All rights reserved  5 
 FIG. 1  Typical layout for cutting test pieces from the roll   
 
Table 2  Requirements of bitumen f elts 
Type 
of felt Breaking strength, 
Min, Kg  Pliability t est Storage sticking 
test Heat resistance 
test Pressure 
head test  Water 
absorption 
test, Max  
 warpway  weftway       
       
Type 1  72 24 The roll shall not 
show cracks on 
unfolding  - - - - 
Consider any 
surface rupture 
exce eding 5 mm 
in length as 
failure  - - - - 
Type 2  95 60 The roll shall  not 
show  cracks on  
unrolling  The test  pieces 
shall be examined 
after cooling  The test pieces 
shall show no 
sign of melting 
of bitumen 
compound  The test 
pieces 
shall 
show no 
sign of 
leakag e 5.0 percent  
Consider any 
surface rupture 
exceeding 5 mm 
in length as 
failure  After release of the 
load, the layers of 
the felt shall be 
capable of being 
separat ed without 
damaging the 
coatant in  any way  - - - 
Type 3 
(all 
grades)  
135 90 The roll shal l not 
show cracks on 
unrolling  The test pieces 
shall be examined 
after cooling  The test pieces 
shall show no 
sign of melting 
of bitumen 
compound  The test 
pieces 
shall 
show no 
sign of 
leakage  2.0 percent  
Consider any 
surface rupture 
exceeding 5 mm 
in length as 
failure  After release of the 
load, the layers of 
the felt shall be 
capable of being 
separated without 
damaging the 
coatant in any way  - - - 
NOTE - Appropriate tests f or the abov e requirements are described in 8,  
 
9 Tests  
Tests shall be carried ou t as per the relevant standards mentioned in 8 and as specified in col 2 to 8 of Table 
2. 
9.1 Breaking strength  test  
Breaking strength is the force in Newton which is required for breaking the test piece.  DUS 2265 : 2020  
6 © UNBS 2020  – All rights reserved  
 9.1.1  Apparatus  
9.1.1.1  A standard constant -rate-of transverse type cloth -testing machine having the rate of transverse of 
the moving jaw as 450 mm/min.  
9.1.1.2  Cutting tools for preparation of the samples.  
9.1.2  Procedure  
9.1.2.1  Preparation of Test Sample  
From the sample of felts, 5 test pieces 75 mm wi de and 180 mm long between the grips shall be cut in both 
longitudinal and transverse direction (see Fig. 1).  
9.1.2.2  Conditioning  
The test pieces shall be conditioned for 48 hours at 27 ± 2°C and 6 5 ± 5 percent relative humidity.  
5.1.2.3  Testing  
Each of the test pieces shall be fixed between the jaws of the testing machine fixed at a distance of 180 mm 
and the breaking point to be noted in Newton from the dial gauge. The force in Newton shall be read from the 
dial gauge. All the five samples cut from both  the directions shall be tested.  
NOTE - The test shall be carried out not earlier than 3 days from the date of manufacture.  
9.1.3  Reporting of the result  
9.1.3.1   Record the breaking strength in Newton, for each of the test piece.  
9.1.3.2  The value of brea king strength in warp and weft shall be average of the five test pieces in both 
the directions.  
9.2 Pliability  
Pliability of a felt is the resistance of the felt against damage or crack on being unrolled on a fairly smooth and 
flat surface.  
9.2.1  Apparatus  
4.2.1.1  A metallic mandrel of diameter ranging from 50.0 m m to 75 .0 mm made from a piece of pipe or 
bar of the correct diameter, slotted in such a manner that one end of the felt strip can be inserted.  
4.2.1.2 Arrangement to obtain temperature up to  - 15°C to condition the samples depending up  on the 
type of felt.  
9.2.2  Procedure  
9.2.2.1  Preparation of Sample   
Ten test pieces, 25 mm wide and at least 2 50 m m long shall be cut from each of the samples, five in 
longitudinal direction and five in the transvers e direction.  
9.2.2.2  Conditioning   
The test pieces in each direction shall be conditioned for 3 hours at the required temperature and immediately 
tested.  DUS 2265 : 2020  
© UNBS 2020  – All rights reserved  7 
 9.2.2.3  Procedure   
The test pieces shall be wound round a mandrel at a uniform speed of 25 min/s. The strip shall be placed on a 
plain surface, the loose end held down by suitable clamp, and the mandrel then rolled over the felt to bend it 
at the required speed maintaining contact with the mandrel surface throughout. Unrolled test piece shall be 
checked fo r any crack and rupture.  
9.2.3  Reporting  
It shall be reported whether the roll shows any cracks o r rupture exceeding 5 m m after unrolling.  
9.3 Storage sticking property  
The property of felt due to which layers of felts kept together have tendency to stick.  
9.3.1  Apparatus  
A chamber, suitably fitted with a thermos -state, capable of maintaining a constant temperature of 55  20C or 
higher temperature as per the requirement of the particular type of the felt for 18 hours .  
9.3.2  Procedure  
9.3.2.1  Preparation  of Test Specimen   
Four test pieces of size 100 X 100 mm from each of the sample shall be taken  
9.3.2.2  Testing  
9.3.2.2.1  Four test pieces shall be kept one above other in the chamber as shown in Fig. 1 and shall be 
subjected to a constant pressure of (0.7 kg/cm2) for 18 hours. The, temperature of the chamber shall be 
maintained at 55  2°C throughout the period.  
9.3.2.2.2  After 18 hours, load shall be released and test pieces shall be taken out and checked.  
9.3.3  Reporting  
The report shall be to indicate wh ether layers of felt is capable of being separated without damaging the coats 
in any way.  
9.4 Pressure head test   
9.4.1  Apparatus  
9.4.1.1  An arrangement to put a circular test piece of diameter 200 mm under a constant pressure head 
of water of 300 mm ( for  a typical arrangement of the apparatus, see Fig. ).  DUS 2265 : 2020  
8 © UNBS 2020  – All rights reserved  
 
 
9.4.1.2  An arrangement to condition the sample at a temperature of 5°C and 65 f 2°C.  
9.4.2  Procedure  
9.4.2.1  Preparation of Test Pieces  
Six test pieces, at least 200 mm in diameter, shall be cut from e ach of the samples selected in such a manner 
that when the test piece is clamped down, a part of it is always extending beyond the clamping plate.  
9.4.2.2  Conditioning  
a) Three test pieces shall be conditioned for 3 h at 65  2°C. 
b) Three test pieces shall be c onditioned at 5°C or lower temperature as per requirement for 3 h and 
immediately tested.  
9.4.2.3  Procedure  
Test pieces conditioned as explained in 5.2 shall be placed one by one as shown in Fig. 1 and shall be 
subjected to constant pressure head of 300 mm  high and checked periodically for any leakage for one hour.  
9.4.3  Reporting  
Reporting shall include the following:  
a) Date of testing,  
b) Type of conditioning, and  
c) Observation.  
9.5 Heat resistance property  
The property of felt which indicates its resistance aga inst high temperature so as to not show any sign of 
melting.  
9.5.1  Apparatus  
A chamber suitably fitted with a thermostat to keep a constant required temperature.  
9.5.2  Procedure  
9.5.2.1  One test piece of size 100 X 100 mm from each of the samples. At least  five test pieces shall be 
taken.  DUS 2265 : 2020  
© UNBS 2020  – All rights reserved  9 
 9.5.2.2  All the test pieces shall be kept suspended vertically by means of clips, in a chamber at the 
required temperature for three hours.  
9.5.2.3  At the end of the period samples shall be taken out of the heated chamber and examined visually 
for signs of melting of the bitumen compound.  
9.5.3  Reporting  
Reporting shall include the following:  
a) Date of testing,  
b) Detail of sample, and  
C) Observation.  
9.6 Water absorption test  
9.6.1  Apparatus  
9.6.1.1  Balance  
9.6.1.2  Troug h to immerse Sample in Water   
9.6.1.3  Arrangement for Hanging the Samples Diagonally  
9.6.2  Procedure  
9.6.2.1  From the sample selected, cut a strip 300 mm wide across the roll. Divide this into three equal 
test pieces 300 x 300 mm and weigh the central tes t piece to nearest 0.1 g.  
9.6.2.2  Immerse the central test piece completely in distilled water for 24 hours.  
9.6.2.3  Remove the test pieces and hang the test pieces immediately diagonally for air drying in room at 
27  2°C and 65 f 5 percent relative humid ity for 45 minutes. Reweigh the sample to nearest 0.1 g.  
9.6.3  Calculation  
Calculate the water absorption as the percentage weight increase as given below:  
 
where  
M1 = mass of the piece before immersion in distilled water, and  
M2 = mass of the piece after  hanged for 45 minutes.  
 
9.6.4  Reporting  
Reporting shall include the following:  
a) Date of testing,  DUS 2265 : 2020  
10 © UNBS 2020  – All rights reserved  
 b) Type of conditioning, and  
c) Observation.  
9.7 Determination of binder content test 
9.7.1  Apparatus  
9.7.1.1  The apparatus  shall consist of normal Soxhlet capable of holding extraction thimble and flask of 
500 ml capacity with ground glass joint to fit the Soxhlet.  
9.7.1.2  A suitable electric mentle heater with regulator or a gas ring.  
9.7.1.3  Extraction thimble made of single layer filter paper (which shall  not allow any filler material to pass 
through) of dimension generally of 25 mm dia meter  and 80 -100 mm long and properly shaped.  
9.7.2  Solvent  
9.7.2.1  The solvent shall be benzene or trichloroethylene.  
9.7.2.2  Size of Sample  
One test piece of 15 cm x 10 cm  of the bitumen felt shall be taken for the test.  
9.7.3 Procedure  
9.7.3.1  The thimble shall be dried at 100oC to 110°C, then coole d in a desiccator and weig hed. The 
bitumen felt sampl e shall be weighed nearest to 0. 1 g and is folded and put in the thimble.  The sample of the 
felt shall be cut  into pieces, if  necessary, to be accommodated i n the thimble.  
9.7.3.2  About 400 ml of the solvent shall be taken into the properly cleaned and dried flask and the 
soxhlet shall be fitted over the flask. Care should be t aken that the ground glass fittings are perfect and there 
is no leakage.  
9.7.3.3  After fixing the reflex condenser , heat shall be appl ied at the bottom of the flask slowly. The 
heating should be adj usted to ensure a stea dy reflux of 60 -70 drops per mi nute falling from the end of the 
condenser  on the middle of the extraction thimble. It is to be observed that at least three cycles of siphoning of 
solvent is taken place in 10 minutes.  
9.7.3.4  Refluxing shall be continued until extraction is completed. This ma y be understood when the 
solvent siphoned to the flask is clear.  
9.7.3.5  The thimble with extracted hessian and filter shall be taken out and dried  to constant weight at 
100°C -110oC. 
9.7.4 Calculation  
9.7.4.1  The binder content B shall be calculated  on the  dry sample by means of the following formula:  
B = [(M 1 - M2)/M 1] X 100  
where  
M1 = weight of the sample in g, and   
M2 = weight of the recovered hessian base with filler in g.  DUS 2265 : 2020  
© UNBS 2020  – All rights reserved  11 
 In order to, correct for any fine material present in the solution at the end of the test, the solvent shall be 
distilled off, the residue cooled down and weighed and a representative portion of it (between 2 and 3 g) 
treated with the solvent and filtered through a sintered silica filtering crucible or filter paper.  
9.7.4.2  In the case  of materials containing high filler content the whole of the solution at the end of the 
test should be filtered or centrifu gal. The binder content B shall be calculated  on the dry sample by the 
following formula:  
B = [M1 (M2 - M3) /M1]x 100 percent by mas s 
where  
M1 = mass of sample in g;  
M2 = mass of recovered hessian base in g;  and 
M3 = mass of filler, if any, reclaimed from  the extracted bitumen solution either  by centrifuging or by 
decantation after settlement.  
10 Sampling and criteria of conformity  
10.1 Sampling  
10.1.1  Lot 
10.1.1.1  The conformity of the lot to the requirements of this standard shall be determined on the basis of 
inspection and tests carried out on the samples selected from the lot.  
10.1.2  The number of rolls to be selected from the lot  shall depend upon the size of the lot and shall be in 
accordance with col 1 and 2 of Table 3.  
10.1.2.1  These rolls shall be selected at random from the lot, and in order to ensure randomness of 
selection, random number tables may be used. In case random n umber tables are not available, the following 
procedure may be adopted for the selection of the rolls.  
Starting from an y roll in the lot count them as  1, 2, 3, .... . .. , r, and so on, in order. Every rth roll thus counted 
may be selected till the requis ite number of rolls for the sample is obtained, r being the integral part of N/n, 
where N is the number of rolls in the lot, and the number of roll s to be selected in the sample.  
10.1.3  Test samples and number of t ests  
10.1.3.1  All the rolls selected in 10.1.2 shall be inspected for width, length and visible external defects.   
10.1.3.2  The number of rolls to be tested for breaking strength, pliability and storage sticking, heat 
resistance, water absorption test, pressure head test and binder content shall be in accordance with col 4 of 
Table 3. These rolls shall be taken at random from those inspected  under 10.1.3.1 and found satisfactory for  
dimensions. From each of these rolls, one test  sample 5 m long and the full width of the felt  shall be cut out for 
preparing test specimens.  Test samp le shall not be taken from dam aged  portion of the roll, if any. The 
required number  of test specimens shall be taken from each of the test sample and subjected to the 
corresponding tests.  
10.1.3.3  From each sample the test  specimens shall be cut  out in the manner shown in Fig.1, which  
depicts the layout of test specimens.  
 DUS 2265 : 2020  
12 © UNBS 2020  – All rights reserved  
 Table 3 - Sample s ize and  criterion of conformity  
No. of rolls in a lot  No. of rolls to be selected 
in a sample  Permissible No. of 
defective rolls  Sub-sample sizes, No. of 
rolls to be selected in a 
sample  
Up to 100  5 0 2 
101 to 150  8 0 3 
151 to 300  13 0 4 
301 to 500  20 1 5 
501 to 1 000  32 2 6 
1 001 to 3000  50 3 8 
3001 and above  80 5 10 
 
10.1.4  Criteria for Conformity  
10.1.4.1  The lot shall be con sidered to be in conformity with the requirements of the standard if the 
following conditions are satisfied:  
a) The number of rolls found defective with respect to any characteristics mentioned in 10.1.3.1 
does not exceed the corresponding number given in col  3 of Table 3.  
b) From the observed values of breaking strength, the average X and the range R are calculated for 
each direction (that is, warp -way and weftway) separately, and the value of the expression X - 0·6 R is 
found to be greater than or equal to the applicable specified value.  
NOTES  
1. Average X is the value obtained by dividing the sum of the observed values by tit le number of observed 
values.  
2. Range R is (he difference between the maximu m and the minimum in a set of observed values.  
c) All the sample roll s tested for water absorption shall satisfy the conditions of clause 9.6  
individually.  
d) For the other characteristics mentioned in 10.1.3.2 (except breaking strength and water 
absorption), all the test pieces satisfy all the requirements of the characterist ics individually.  
11 Packing and marking  
11.1 Packing  
Unless otherwise sp ecified, bitumen felts should  be securely packed in roll s. The rolls of hessian base Type 3 
bitumen felts shall be wound on cores and the fibre base Types 1 and 2 bitumen felts need n ot be wound on 
cores, but they shall be securely wrapped in a kraft paper of the same width as tit le fabric. The wrapper shall 
completely encircle the roll and shall be pasted at the overlap in manner that will prevent it from opening out. 
The ends of the full need not be covered.  
11.2 Marking  
Each package shall be legibly and indelibly marked with the following information:  
a) Name  of manufacturer;  DUS 2265 : 2020  
© UNBS 2020  – All rights reserved  13 
 b) Type and grade of the bitumen felt;  
c) Lengt h, width and weight of the roll ; and  
d) Batch number in code and date of m anufacture.  DUS 2265 : 2020  
14 © UNBS 2020  – All rights reserved  
 Bibliography  
[1] IS 1322: 1993; Bitumen felts for water -proofing and damp -proofing – specification  
 
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© UNBS 2020  – All rights reserved  15 
 Certification marking  
Products that conform to Uganda standards may be marked with Uganda National Bureau of Standards 
(UNBS) Certification M ark 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 Uganda National B ureau 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 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 Bureau of Standards.  
 
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ICS nn.nnn.n n 
Price based on nn pages  
© UNBS 2020 – All rights reserved