DRAFT UGANDA STANDARD  
  DUS 706  
Second Edition  
2021 -mm-dd 
 
 
 Reference number  
DUS 706: 2021  
© UNBS 2021   
  
Non-woven surgical dressing  — Specification   
 
 
 
 DUS 706: 2021  
ii © UNBS 2021  – All rights reserved  
 Compliance with this standard does not, of itself confer immunity from legal obligations  
A Uganda Standard does not purport to include all necessary provisions of a contract. Users are 
responsible for its cor rect application  
© UNBS  2021   
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilised in any 
form or by any means, electronic or mechanical, including photocopying and microfilm, without prior written 
perm ission 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 706:2021  
© UNBS 2021  – All rights reserved  iii 
 Contents  Page 
Foreword  ................................ ................................ ................................ ................................ .................  v 
1 Scope  ................................ ................................ ................................ ................................ ..........  1 
2 Normative references  ................................ ................................ ................................ ..................  1 
3 Terms and definitions  ................................ ................................ ................................ .................  1 
4 Types  ................................ ................................ ................................ ................................ ..........  2 
5 Fibre composition  ................................ ................................ ................................ .......................  2 
6 Requirements  ................................ ................................ ................................ ..............................  2 
6.1 General requir ements  ................................ ................................ ................................ .................  2 
6.1.4  Unpadded swabs ................................ ................................ ................................ .........................  3 
6.1.5  Padded  swabs  ................................ ................................ ................................ .............................  3 
6.1.6  Surgical pads  ................................ ................................ ................................ ..............................  4 
7 Sterility  ................................ ................................ ................................ ................................ ........  4 
8 Other  requirements  ................................ ................................ ................................ .....................  5 
9 Packaging  ................................ ................................ ................................ ................................ ... 5 
10 Labelling  ................................ ................................ ................................ ................................ ..... 5 
11 Sampling  ................................ ................................ ................................ ................................ ..... 6 
Annex  A (normative)  Conditioning of textiles and standard temperate atmosphere for 
determining their physical and mechanical properties  ................................ ...............................  7 
A.1 Principle  ................................ ................................ ................................ ................................ ...... 7 
A.2 Standard temperate atmosphere for testing ................................ ................................ ................  7 
A.3 Pre-cond itioning  ................................ ................................ ................................ .........................  7 
A.4 Conditioning  ................................ ................................ ................................ ...............................  7 
Annex  B (normative)  Determination of dimensions ................................ ................................ ................  8 
B.1 Width  of a textile fabric sample  ................................ ................................ ................................ ... 8 
B.1.1  Apparatus  ................................ ................................ ................................ ................................ ... 8 
B.1.2  Procedures ................................ ................................ ................................ ................................ .. 8 
B.1.3  Calculation  ................................ ................................ ................................ ................................ .. 8 
B.2 Length of a textile fabric sample  ................................ ................................ ................................ . 8 
B.2.1  Apparatus  ................................ ................................ ................................ ................................ ... 8 
B.2.2  Preparation of test specimen  ................................ ................................ ................................ ...... 8 
B.2.3  Procedure  ................................ ................................ ................................ ................................ ... 9 
B.2.4  Calculation  ................................ ................................ ................................ ................................ .. 9 
Annex C (normative )  Textiles — Mass per unit area of conditioned fabrics  ................................ ........  10 
C.1 General ................................ ................................ ................................ ................................ ...... 10 
C.2 Principle  ................................ ................................ ................................ ................................ .... 10 
C.3 Apparatus  ................................ ................................ ................................ ................................ . 10 
C.4 Procedure  ................................ ................................ ................................ ................................ . 11 
C.4.1  General ................................ ................................ ................................ ................................ ...... 11 
C.4.2  Procedure 1: Full -width specimen ................................ ................................ .............................  11 
C.4.3  Procedure 2: for representative large cuttings  ................................ ................................ ..........  11 
C.4.4 Procedure 3: for several small (0.01 m2) specimens ................................ ................................ ..... 11 
C.5 Calculation  ................................ ................................ ................................ ................................  12 
C.6 Test report ................................ ................................ ................................ ................................ . 12 
Annex D (normative)  Water absorption rat e of textile fabrics ................................ ...............................  13 
D.1 Principle  ................................ ................................ ................................ ................................ .... 13 DUS 706: 2021  
iv © UNBS 2021  – All rights reserved  
 D.2 Applicability  ................................ ................................ ................................ ..............................  13 
D.3 Apparatus  ................................ ................................ ................................ ................................ .. 13 
D.4 Preparation of test specimens ................................ ................................ ................................ ... 13 
D.5 Procedure  ................................ ................................ ................................ ................................ .. 14 
D.6 Calculation  ................................ ................................ ................................ ................................  14 
Annex E (normative)  Non -volatile matter content and ash content of non -volatile matter ....................  15 
E.1 General  ................................ ................................ ................................ ................................ ...... 15 
E.2 Appara tus ................................ ................................ ................................ ................................ .. 15 
E.3 Procedure  ................................ ................................ ................................ ................................ .. 15 
E.4 Calculation  ................................ ................................ ................................ ................................  16 
Annex F (normative)  Presence of dyes in absorbent textile fabrics  ................................ .....................  17 
F.1 Apparatus  ................................ ................................ ................................ ................................ .. 17 
F.2 Reagent  ................................ ................................ ................................ ................................ ..... 17 
F.3 Preparation of test specimen  ................................ ................................ ................................ .... 17 
F.4 Procedure  ................................ ................................ ................................ ................................ .. 17 
F.5 Evaluation  ................................ ................................ ................................ ................................ . 17 
F.6 Test report  ................................ ................................ ................................ ................................ . 17 
Annex G (normative)  ................................ ................................ ................................ .............................  19 
G.1 Introduction  ................................ ................................ ................................ ...............................  19 
G.2 Fluid thioglycollate medium  ................................ ................................ ................................ ...... 19 
G.3 Alternative thioglycollate medium  ................................ ................................ .............................  20 
G.4 Soya -bean casein digest medium ................................ ................................ ..............................  20 
G.5 Sterility  ................................ ................................ ................................ ................................ ...... 21 
G.6 Growth promotion test of aerobes, anaerobes, and fungi  ................................ .........................  21 
Bibliography  ................................ ................................ ................................ ................................ ..........  22 
 DUS 706:2021  
© UNBS 2021  – All rights reserved  v 
 Foreword  
Uganda National Bureau of Standards (UNBS) is a parastatal under the Ministry of Trade , Industry and 
Cooperatives established under Cap 327 , of the Laws  of Uganda , as amended .  UNBS is mandated to co -
ordinate the elaboration of standards and is  
(a) a member of International Organisation for Standardisation (ISO) and  
(b) a contact point for the WHO/FAO Codex Alimentarius Commission on Food Standards, and  
(c) the Na tional 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 co nsists 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. T he committee reviews the comments before recommending the draft standards 
for approval and declaration as Uganda Standards by the National Standards Council.  
The committee responsible for this document is Technical Committee UNBS /TC 307, Medical devices an d 
equipment . 
This second edition cancels and replaces the first edition ( US 706: 2011), which has been technically revised .  DRAFT UGANDA STANDARD  DUS 706: 2021  
 
© UNBS 2021  – All rights reserved  1 
 
 Non-woven surgical d ressing  — Specification  
1 Scope   
This Draft Uganda Standard specifies  the requirements, sampling  and m ethods of test for three types of non -
woven surgical dressings; unpadded swabs, padded swabs and surgical pads.  
2 Normative references   
The following referenced documents referred to in the text in such a way that some or all of their content 
constitutes r equirements 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.  
US ISO 1833 (all parts), Textiles — Quantitative chemical analysis  
US ISO 2859 -1, Sampling procedures for inspection by attributes - Part 1: Sampling schemes indexed by 
acceptance quality limit (AQL) for lot -by-lot inspection  
US ISO 3071 , Textiles - Determination of pH of aqueous extract  
US ISO 10993  (all parts ), Biological evaluation of medical devices  
US ISO 13938 (all parts), Textiles  — Bursting  properties  of fabrics   
3 Terms and definitions   
For the purposes of this document, the following terms and definitions apply. ISO and IEC maintain 
terminological databases for use in standardization at the follo wing addresses: — ISO Online browsing 
platform: available at http://www.iso.org/obp  
3.1 
bursting strength  
multi-directional resistance to rupture of a circular fabric specimen  
3.2 
fibre  
textile raw material, generally characterized by flexibility, fineness  and high ratio of length to thickness  
3.3 
gauze  
fine lightweight,  open -texture  fabric  produced  in plain weave  or in a simple  leno weave  
3.4 
non-woven  fabric  
fabric normally made from continuous filaments or from staple -fibre webs or batts strengthened b y bonding  
using  various  techniques  including  adhesive  bonding,  mechanical  interlocking  by needling  or fluid jet 
entanglement,  thermal  bonding  and stitch  bonding  DUS 706: 2021  
2 © UNBS 2021  – All rights reserved  
 
 3.5 
swab  
surgical dressing pad consisting of several layers of absorbent fabric, and used to pr epare the site of an  
operation or a wound, to absorb and remove excess blood and body fluids from an incision, and for packing  
internal  body  cavities  during  an operation  
3.6 
wadding  
lofty sheet  of fibres,  which  might  be bonded,  and used  for padding,  stuffi ng, or packing  
3.7 
weave  
pattern  of interlacing  of warp  and weft in a woven  fabric  
3.8 
warp  
threa d running lengthwise and parallel to a selvedge  
3.9 
weft 
thread  running  width wise  in a fabric as  woven  
4 Types  
Non-woven surgical dressings shall be one of the following types ,  
a) unpadded swabs;  
b) padded swabs; and  
c) surgical pads.  
5 Fibre composition  
When determined in accordance with a relevant part of ISO 1833 , the fibre composition of the components of 
the non -woven surgical dressings shall be as follows:  
a) non-woven fabric: cotton,  viscose or thermos bonding fibres (for example, polypropylene); and  
b) wadding; either cotton, viscose or polyester fibres (or a mixture of two or more of these fibres) or 
bleached cellulose pulp.  
6 Requirements  
6.1 General requirements  
6.1.1 Non-woven surgi cal dressing shall be free any spinning, weaving or processing defects and any 
foreign matter.  
6.1.2  When tested in accordance with the relevant parts of ISO 10993, non-woven surgical dressing  shall 
be non -toxic, hypoallergenic and non -irritating.  
6.1.3 Non-woven  fabric  DUS 706: 2021  
 
© UNBS 2021  – All rights  reserved  3 
 
 Non-woven  fabric  used  in surgical  dressings  shall comply  with the requirements  given  in Table  1. 
Table  1 — Non-woven  fabric  requirements  
Characteristic  Requirement  Test  method  
Mass  per unit area,  g/m2, min. 13 Annex C 
Bursting  strength,  kPa, min. 35 US ISO 13938  
 
6.1.4 Unpadded swabs  
6.1.4.1 Construction  
An unpadded swab shall have been made from a single piece of non -woven fabric that has been so folded to  
the appropriate size that no raw edge is visible, or so processed that the raw ed ge is non -linting, non -adherent  
and smooth.  
6.1.4.2 Size,  ply and mass  
When determined in accordance with Annex B and C, the  nominal size of, and number of plies in, a swab 
shall,  unless  otherwise  specified  by the purchaser,  be one of the combinations  given in columns  1 and 2 of 
Table  2, as specified, and the mass of 10 swabs of the same size and ply shall be at least equal to the 
appropriate  minimum  value  given  in column  3. 
Table  2 — Size, ply  and mass  of unpadded swabs  
 
Nominal size,  mm Number of plies  Minimum mass of 10 swabs,  g 
75 x 75  2 1.5 
75 x 75  4 3 
75 x 75  8 6 
75 x 75  12 9 
100 x 100  2 2.5 
100 x 100  4 5 
100 x 100  8 10 
100 x 100  12 16 
6.1.5 Padded  swabs  
6.1.5.1 Construction  
A padded swab shall have been made from a single piece of non -woven f abric that has a thin layer of wadding  
at its centre and has been so folded to the appropriate size that the swab contains at least two plies and no  
raw edge is visible, or so processed that the raw edge is non -linting, non -adherent and smooth. Where  
bleac hed cellulose pulp is used as wadding, the wadding shall be encased in non -woven tissue, followed by  
encasement  in non-woven  fabric,  so as to prevent  the loss of short,  loose  fibres.  DUS 706: 2021  
4 © UNBS 2021  – All rights reserved  
 
 6.1.5.2 Size and mass  
When determined in accordance with annexes B and C , the nominal size of a padded swab shall be one of 
those  given in column 1 of Table 3, as specified by the purchaser, and the mass of 10 swabs of the same size 
shall be at least  equal  to the appropriate  minimum  value  given  in column  2. 
Table 3 — Size and mass of padded swabs  
 
Nominal size,  mm Minimum  mass  of 10 padded  swabs,  g 
50 x 50 5 
75 x 75 9 
100 x 100 15 
 
6.1.6 Surgical pads  
6.1.6.1 Construction  
A surgical pad shall consist of a thick layer of wadding enclosed in a tube (either open -ended or  sealed)  
formed from one or more pieces of non -woven fabric, with the cut edges adequately sealed along the length of  
the pad. Where bleached cellulose pulp is used as wadding, the wadding shall be encased in non -woven  
tissue,  followed  by encasement  in non-woven  fabric,  so as to prevent  the loss of  short,  loose  fibres.  
6.1.6.2 Type  
Surgical  pads  shall be of type A, B or C, as  specified  by the purchaser  (see Table  4). 
6.1.6.3 Size and mass  
When determined in accordance with Annexes B and C, the nominal size of a surgical pad shall be one of 
those given in column 1 of table 4, as specified by the purchaser, and the mass of 10 surgical pads of the 
same size shall be at least equal to the appropriate minimum value given in column 2, 3 or 4, as relevant . 
Table  4 — Size and mass  of surgical  pads  
 
Nominal size,  mm Minimum  mass  of 10 surgical  pads , g 
Type  A Type  B Type  C 
100 x  100 36 29 19 
100 x  200 70 57 39 
200 x  200 140 109 73 
200 x  400 280 219 147 
400 x  400 560 - - 
7 Sterility  
If sterile , the dressings sha ll be tested in accordance with Annex G. DUS 706: 2021  
 
© UNBS 2021  – All rights  reserved  5 
 
 8 Other  requirements  
All types  of non-woven  surgical  dressings  shall comply  with the requirements  given  in Table  5. 
Table  5 — Other  requirements  for all  types  of surgical  dressings  
 
S.No  Characteristic  Requirem ent Test  method  
i) Fluorescence  Not more than the occasional point of intense blue 
fluorescence  Annex C 
ii) Absorption rate, s ,max  10 Annex D  
iii) Ash content, g/kg, max.  5 Annex E  
iv) pH value of aqueous extract  7 ± 2  US ISO 3071  
v) Freedom from dy es The percolate may show a yellow colour, but no blue or 
green tint shall appear  Annex F.  
9 Pack aging 
9.1 The dressing shall be packaged in suitable packaging materials, which shall protect the product from 
contamination and damage during transportation,  handling and storage . 
9.2 Only dressings of the same type and nominal size, and in the case of unpadded  swabs, number of 
plies, shall be packed together in a package and in a bulk container. Sealed and sterile - packed  packages  
shall be packed  in separate  bulk containers.  
10 Labelling  
Each package shall be  in legible and indelible mark ed or a label  securely  attached  to the package  
with the following information  
a) manufacturer's  name,  physical address  and trade  mark;  
b) type of dressing,  the nominal  size (in millimetres)  and, in the case  of unpadded  swabs,  the number  of 
plies;  
c) type,  in the case  of surgical  pads ; 
d) the word  "sterile"  in the case  of a sterile -packed  dressing;  
e) quantity  of dressings;  
f) batch  identification  number;   
g) country of origin;  
h) date of manufacture  
i) expiry  date;  and 
j) and conditions  of storage . 
k) information on disposal  after use  DUS 706: 2021  
6 © UNBS 2021  – All rights reserved  
 
 11 Sampling  
Sampling shall be done in accordance with US ISO 2859 -1. DUS 706: 2021  
 
© UNBS 2021  – All rights  reserved  7 
 
 Annex  A 
(normative)  
 
Conditioning of textiles and standard temperate atmosphere for 
determining their physic al and mechanical properties  
A.1 Principle  
Textile samples are conditioned in an atmosphere of a specified humidity and a specified temperature .  
A.2 Standard temperate atmosphere for testing  
An atmosphere that has a relative humidity of 65 % ± 2 % and a temperature of 20 °C ± 2 °C at the prevailing 
barometric pressure.  
A.3 Pre-conditioning  
If pre -conditioning is required, dry the textile to substantially constant mass in an atmosphere that has a 
relative humidity between 10 % and 25 % and a temperatur e not exceeding 50 °C.  
A.4 Conditioning  
Before a textile is tested in order to establish a physical or mechanical property, condition it in the standard 
atmosphere for testing. A textile is conditioned when (after having been pre -conditioned, if necessar y), it has 
reached equilibrium with the standard atmosphere for testing. Provided that there has been a free flow of 
conditioned air through the textile throughout the entire period of conditioning, consider a textile to be in 
equilibrium with the atmosphe re if the change in mass between successive weighing, carried out at interval of 
two hours is less than 0.25 %.  DUS 706: 2021  
8 © UNBS 2021  – All rights reserved  
 
 Annex  B 
(normative)  
 
Determination of dimensions   
B.1 Width of a textile fabric sample   
The wi dth of a textile fabric sample laid on a flat surface is measured with a steel scale.  
B.1.1  Apparatus  
Steel scale, of a length exceeding the width of the fabric to be measured, and is graduated in centimetres and  
millimetres  
B.1.2  Procedures  
B.1.2.1  Lay the test sample flat and full width (without subjecting it to tension) on a plane surface and  
condition it in that state for at least 24 h in accordance with Annex A.  
B.1.2.2  Take, to the nearest 1 mm, five measurements across the overall width or bet ween the innermost  
selvedge threads (as relevant) of the conditioned test sample at approximately equal intervals throughout its  
length.  
B.1.3  Calculation  
Calculate the arithmetic mean of the five measurements and record it as the width of the sample  
B.2 Length of a textile fabric sample  
B.2.1 Apparatus  
B.2.1.1  Marking pen  
B.2.1.2  Steel tape, of length greater than the length of the laboratory sample to be measured, and 
graduated in centimetres and millimetres  
B.2.2 Preparation of test specimen  
B.2.2.1 Lay the laboratory sample flat and full width (without subjecting it to tension) on a plane surface 
and condition it in that state for at least 24 h in accordance with Annex A.  
B.2.2.2  From the conditioned laboratory sample cut a test specimen across th e full width of the laboratory  
sample along a datum line drawn at right angles to the selvedge and as close as possible to the beginning  DUS 706: 2021  
 
© UNBS 2021  – All rights  reserved  9 
 
 and the end of the laboratory sample.  
B.2.3  Procedure  
Take, to the nearest  millimetre, five measurements ( B.1.2.2 ) of the length of the test specimen at  
approximately equal intervals across its width.  
B.2.4  Calculation  
Calculate the arithmetic mean of the five measurements and record it as the length, in metres  DUS 706: 2021  
10 © UNBS 2021  – All rights reserved  
 
 Annex C  
(normative )  
 
Textiles — Mass per unit area of c onditioned fabrics  
C.1 General  
C.1.1 This standard specifies three alternative procedures for determining the mass per unit area of woven  
fabrics (including those of the stretch type), knitted fabrics, non -woven fabrics, composite fabrics and narrow  
fabrics, that have been conditioned in the standard atmosphere for testing.  
C.1.2 The three procedures apply to:  
a) full-width fabrics that are of such a length that they can be conditioned and measured satisfactorily;  
b) representative large cuttings that can be  measured satisfactorily; or  
c) a number of representative specimens cut to a constant area of 0.01 m2  
Smaller areas are not considered suitable for testing.  
C.1.3  Procedure 3 is not applicable to knitted fabrics and woven stretch -type fabrics.  
C.1.4  If so specified in the relevant product specification, or if so agreed upon between the parties  
concerned, a correction for the non -fibrous material content of the fabric may be made.  
C.2 Principle  
The mass and the dimensions of a textile fabric specimen, th at is without tension and has been conditioned in  
the standard test atmosphere, is determined and the mass per unit area is calculated.  
C.3 Apparatus  
C.3.1  Table, with a smooth flat surface and is of a size that exceeds that of the fabric to be measured  
C.3.2 Pair of scissors or suitable cutter, capable of cutting a square or circular specimen of area 0.01 m2  
to an accuracy of 1 % or better  
C.3.3 Metal plate, is 5 m m smaller than the cutter (see C .3.2) and that has a thickness of 10 mm  
C.3.4 Balance, c apable of determining the mass of the specimen to an accuracy of 0.2 % or, in the case of  
0.01 m2 specimens, to an accuracy of 0.001 g  DUS 706: 2021  
 
© UNBS 2021  – All rights  reserved  11 
 
 C.4 Procedure  
C.4.1 General  
Condition the sample in accordance with Annex A and carry out the test in the same standar d atmosphere  
NOTE 1  Any of the procedures can be used to determine the mass per unit area of a fabric; however, for the purpose 
of greater accuracy, the procedure that gives the largest test specimen(s) is preferable.  
NOTE 2  In the case of narrow fabrics,  a complete roll should be used, but, if this is not possible, the length of the 
specimen should be at least 5 m.  
C.4.2 Procedure 1: Full -width specimen  
C.4.2.1  Ensure that the fabric, which should preferably be selected from the middle of a piece, is no t less  
than 0.5 m and not more than 4 m long, and lay it flat, and without tension, on the table. Cut at both ends,  
across the full width of the sample, along parallel lines at right angles to the selvedge. If the mass per unit  
area of a selvedge on a f ull-width piece appears to deviate appreciably from the mass per unit area of the  
body of the fabric, or if so agreed upon between the parties concerned, trim off the selvedge along the  
outermost threads of the body of the fabric and use only the body of  the fabric for the determination of the  
mass per unit area. Measure the width and lengt h of the specimen, using Annex B .  
C.4.2.2  Use the balance to determine the mass of the specimen.  
C.4.3  Procedure 2: for representative large cuttings  
C.4.3.1  Ensure  that the available cutting is representative of the sample. Trim the cutting into a square or  
rectangular specimen by cutting along parallel lines at right angles to the warp (length) direction and at right  
angles to the weft (width) direction.  
C.4.3.2  Measure the width and length of the specimen, using Annex B.  
C.4.3.3  Determine the mass of the specimen using the balance.  
C.4.4 Procedure 3: for several small (0.01 m2) specimens  
NOTE On fabrics with large in -woven designs, which involve local areas o f appreciably different mass per  unit area, the 
use of Procedure 1 or Procedure 2 is preferable. If the sample size necessitates the use of Procedure 3, select specimens 
that contain an integral number of pattern repeats or that are representative of the p attern.  
C.4.4.1  Cut at least three square pieces, of side length of approximately 150 mm, from areas of the fabric  
selected to represent the sample as fully as possible but not within 50 mm of the selvedge.  DUS 706: 2021  
12 © UNBS 2021  – All rights reserved  
 
 C.4.4.2  Lay each piece flat, and without tensi on, on a suitable cutting surface. Place the metal plate (see 
C.3.2.2) and the cutter (see C.3.3) on each piece in turn and cut out a 0.01 m2 specimen from each piece, 
ensuring that no loss of threads occurs.  
C.4.4.3  Use the balance to determine the mass of the 0.01 m2 specimens, and calculate the mean mass.  
C.5 Calculation  
C.5.1  In the case of Procedure 1 and Procedure 2, calculate the mass per unit area M in grams per square  
metre, using the following formula:  
 
where  
m is the mass, in grams, of the specimen;  
L is the length, in millimetres, of the specimen; and  
W is the width, in millimetres, of the specimen.  
C.5.2  In the case of Procedure 3, calculate the mass per unit area (M in grams per square metre) by  
multiplying the mean mass (in grams) by 100.  
C.5.3  If the mass per unit area free from non -fibrous material is required, correct the calculated mass per  
unit area (see C.5.1 and C.5.2) for the non -fibrous material content, determined (on a separate sample) using  
a suitable method agreed upon between the parties concerned.  
C.6 Test report  
State the following in the test report:  
a) that the test was carried out strictly in accordance with this standard or whether any deviation was 
introduced;  
b)  
c) the test result to the nearest g/m2; and  
d) whether t he test results indicate the mass per unit area free from non fibrous materials  DUS 706: 2021  
 
© UNBS 2021  – All rights  reserved  13 
 
 Annex D 
(normative)  
 
Water absorption rate of textile fabrics  
D.1 Principle  
A prescribed number of textile fabric test specimens are saturated in accordance with a prescribed procedure  
and the arithmetic mean time for complete saturation of the specimens is recorded.  
D.2 Applicability  
D.2.1 This method is applicable to all textiles intended for use as towels, dishcloths, cleaning rags,  
absorbent surgical dressings and for ot her applications where water absorption is important.  
D.2.2 Depending on the intended end use, the textile is either tested in a single layer (towels, dish cloths,  
cleaning rags, etc.) or in two or more layers (absorbent gauze, swabs, lint, etc.).  
D.3 Apparatus  
D.3.1 Container that is filled to a depth of approximately 100 mm with deionised water maintained at a  
temperature of 20 °C ± 2 °C and that has a surface area of adequate size to allow the specimen to float freely  
D.3.2 Suitable balance having a  sensitivity of 0.1 g  
D.3.3 Stop-watch  
D.3.4 Forceps  
D.3.5 Staining agent, for example Congo -red or methylene blue  
D.4 Preparation of test specimens  
D.4.1 Condition the test sample in accordance with Annex A.  
D.4.2 From each sample select five specim ens in such a way that they fully represent the sample, but are  
taken from areas at least 50 mm away from the edges of the sample. Cut square test specimens each of  
mass 2 g ± 0.1 g and, when necessary, so lightly fold a specimen that its size does not e xceed 100 mm x 100  
mm.  DUS 706: 2021  
14 © UNBS 2021  – All rights reserved  
 
 D.4.3 Swabs are usually pre -folded. Test them in such a way that several layers of fabric will be exposed to  
the water.  
D.4.4  In the case of gauze, fold the specimens lightly, keeping the different layers in contact with one  
another to ensure continuous absorption.  
D.4.5 In the case of cleaning rags, where specimens usually have different fibre components, cut from  
increased parts of the specimens equilateral, triangular snippets of side length approximately 50 mm, and  
disreg ard the mass of the specimens  
D.5 Procedure  
D.5.1 By means of the forceps, place a specimen lightly and as flat as possible on the surface of the water,  
and simultaneously start the stop -watch. As soon as the specimen is completely saturated, stop the wat ch.  
D.5.2 Record the time to the nearest 0.1 s but if the required time exceeds 10 s, record the time to the  
nearest 1.0 s.  
D.5.3 Repeat the test on the remaining test specimens.  
D.5.4 If, in the case of bleached or neutral coloured specimens, the satu ration point is difficult to observe,  
add an adequate amount of staining agent to the water.  
D.6 Calculation  
D.6.1 Calculate, to the nearest 1 s, the arithmetic mean of the five test results.  
D.6.2 In the case of cleaning rags, calculate to the nearest 1 s, the mean of the amount of different rags that  
are present in the sample . DUS 706: 2021  
 
© UNBS 2021  – All rights  reserved  15 
 
 Annex E  
(normative)  
 
Non-volatile matter content and ash content of non -volatile matter  
E.1 General  
This standard specifies a method for the determination of the non -volatile ma tter content and the ash content  
of the non -volatile matter.  
E.2 Apparatus  
E.2.1  Silica or porcelain evaporating dish  
E.2.2 Oven , maintained at 110 °C ± 10 °C  
E.2.  Furnace, maintained at 900 °C ± 10 °C  
E.2.4 Dessicator  
E.2.5 Water -bath  
E.2.6 Scale or weighing balance  
E.3 Procedure  
E.3.1 Heat the evaporating dish in the furnace ( E.2.3) for 15 min.  
NOTE If only non -volatile matter is required, heating to 110 °C in the oven will be sufficient.  
E.3.2 Cool the desiccator and weigh it to the nearest 10 m g (m 1).  
E.3.3 Weigh (see E.2.6), to an accuracy of 10 mg, approximately 4 g of the sample  into the evaporating 
dish. Record the mass of the dish and the polish (m 2).  
E.3.4 Heat the evaporating dish on a boiling water -bath (see E.2.5) until most of the vo latile matter has  
evaporated.  
E.3.5 Place the evaporating dish in the oven at 110 °C ± 2 °C for 16 h.  
E.3.6 Remove the dish, cool it in the desiccator (see E.2.4) and then weigh it.  
E.3.7 Reheat the dish in the oven for 2 h periods (weighing it between  each 2 h period as in E.3.6) until the  
last two weighings do not differ by more than 5 mg (m 3).  DUS 706: 2021  
16 © UNBS 2021  – All rights reserved  
 
 E.3.8 Reserve the dish for the determination of the ash content (see E.3.9).  
E.3.9 Slowly char the non -volatile matter (reserved in terms of E.3.8) over a s mall flame and then place the  
dish in the furnace for 15 min  
E.3.10  Remove the dish, cool it in the desiccator then weigh it.  
E.3.11  Repeat the heating and cooling until the last two masses do not differ by more than 5 mg (m 4).  
E.4 Calculation  
E.4.1 Calculate the percentage by mass of the non -volatile matter content (NV) of the sample  as follows:  
 
where  
m1 is the mass, in grams, of the evaporating dish (see E.3.2);  
m2 is the mass, in grams, of the evaporating dish and polish (see E.3.3); and  
m3 is the mass, in grams, of the evaporating dish and non -volatile matter (see E.3.6);  
E.4.2 Calculate the percentage by mass of the ash content (A) of non -volatile matter of the sample  as  
follows:  
 
where  
m1 is the mass, in grams, of the evaporating dish, ( see E.3.2);  
m3 is the mass, in grams, of the evaporating dish and the non -volatile matter (see E.3.6); and  
m4 is the mass, in grams, of the evaporating dish and ash (see E.3.10)  DUS 706: 2021  
 
© UNBS 2021  – All rights  reserved  17 
 
 Annex F 
(normative)  
 
Presence of dyes in absorbent textile fabrics  
F.1 Appar atus  
F.1.1 Funnel, an open -top cylindrical dropping funnel with a capacity of 400 mL and so positioned that the  
percolate drips into the Nessler -tube  
F.1.2 Nessler -tube, with a capacity of 50 mL  
F.2 Reagent  
Ethanol, absolute  
F.3 Preparation of test spe cimen  
F.3.1 Condition the test sample in accordance with Annex A.  
F.3.2 From the conditioned sample prepare a test specimen in the form of a wad with a mass of  
approximately 10 g. Pack the test specimen tightly into the funnel (see F.1.1).  
F.4 Procedure  
Slowly pour the ethanol (see F.2) on to the test specimen, and close the tap of the funnel as soon as the level  
of the percolate has reached the 50 ml mark in the Nessler -tube (see F.1.2).  
F.5 Evaluation  
Examine the percolate in the Nessler -tube by view ing it downwards against a white background, and deem  
the textile fabrics to contain a dye if the percolate has a blue or a green tint.  
F.6 Test report  
Report the following information:  
a) all the data needed to identify the sample tested;  DUS 706: 2021  
18 © UNBS 2021  – All rights reserved  
 
 b) that the test w as carried out in accordance with this standard;  
c) any deviation from this standard;  
d) the test results, as positive or negative for the presence of dyes.  DUS 706: 2021  
 
© UNBS 2021  – All rights  reserved  19 
 
 Annex G 
(normative ) 
 
 
G.1 Introduction  
The test for sterility is carried out under aseptic conditions. In order to achieve such conditions, the test 
environment has to be adapted to the way in which the sterility test is performed. The precautions taken to 
avoid contamination are such that they do not affect any microorganisms that are to be revealed in the test. 
The working conditions in which the tests are performed are monitored regularly by appropriate sampling of 
the working area and by carrying out appropriate controls. The following culture media have been found to be 
suitable for the test for sterility: fluid thioglycollate medium is primarily intended for the culture of anaerobic 
bacteria; however, it will also detect aerobic bacteria. Soya -bean casein digest medium is suitable for the 
culture of both fungi and aerobic bacteria.   
Media for the test may be prepared as described below or equivalent commercial media may be used 
provided that they comply with the requirements of the growth promotion test of aerobes, anaerobes, and 
fungi. The following culture media have be en found to be suitable for the test for sterility: fluid thioglycollate 
medium is primarily intended for the culture of anaerobic bacteria; however, it will also detect aerobic bacteria, 
soybean -casein digest medium is suitable for the culture of both fun gi and aerobic bacteria.  
G.2 Fluid thioglycollate medium  
L-Cystine                     0.5 g  
Sodium Chloride                    2.5 g  
Dextrose Monohydrate/Anhydrous                5.5/5.0 g  
Agar                      0.75 g  
Yeast Extract (water -soluble)                 5.0 g  
Pancreatic Digest of Casein                 15.0 g  
Sodium Thioglycollate                   0.5 g  
or Thioglycolic Acid                   0.3 ml  
Resazurin Sodium Solution (1 g/L of resazurin sodium), freshly prepared        1.0 ml  
Purified Water                     1000 
mL 
pH after sterilization                   7.1±0.2.  
G.2.2 Mix the L -cystine, agar, sodium chloride, glucose, water -soluble yeast extract and pancreatic 
digest of casein with the water R  and heat until solution is effected.  DUS 706: 2021  
20 © UNBS 2021  – All rights reserved  
 
 G.2.3 Disso lve the sodium thioglycollate or thioglycollic acid in the solution and, if necessary, add 1 M 
sodium hydroxide so that, after sterilization, the solution will have a pH of 7.1 ± 0.2. If filtration is necessary, 
heat the solution again without boiling and filter while hot through moistened filter paper.  
G.2.4 Add the resazurin sodium solution, mix and place the medium in suitable vessels which provide a 
ratio of surface to depth of medium such that not more than the upper half of the medium has undergone a 
colour change indicative of oxygen uptake at the end of the incubation period. Sterilize using a validated 
process. If the medium is stored, store at a temperature between 2 °C and 25 °C in a sterile, airtight container.  
G.2.5 If more than the upper one -third of the medium has acquired a pink colour, the medium may be 
restored once by heating the containers in a water -bath or in free -flowing steam until the pink colour 
disappears and cooling quickly, taking care to prevent the introduction of non -sterile ai r into the container. Do 
not use the medium for a longer storage period than has been validated. Fluid thioglycollate medium is to be 
incubated at 30 °C - 35 °C.  
D.2.6 For products containing a mercurial preservative that cannot be tested by the membrane -filtration 
method, fluid thioglycollate medium incubated at 20 °C - 25 °C may be used instead of soya -bean casein 
digest medium provided that it has been validated as described in growth promotion test.  
G.3 Alternative thioglycollate medium  
Where prescribed, justified and authorized, the following alternative thioglycollate medium may be used: 
prepare a mixture having the same composition as that of the fluid thioglycollate medium, but omitting the 
agar and  the resazurin sodium solution, sterilize as in accordance with G.2. The pH after sterilization is 7.1 ± 
0.2. Heat in a water -bath prior to use and incubate at 30 °C - 35 °C under anaerobic conditions.  
G.4 Soya -bean casein digest medium  
Pancreatic Digest of Casein                 17.0 g  
Papaic Digest of Soybean Meal                 3.0 g  
Sodium Chloride                    5.0 g  
Dibasic Potassium Phosphate                 2.5 g  
Dextrose Monohydrate/Anhydrous                2.5/2.3 g  
Puried Water                     1000 ml  
pH after sterilization                   7.3±0.2.  
G.4.1 Dissolve the solids in water R , warming slightly to effect solution. Cool the solution to room 
temperature. Add 1 M sodium hydroxide, if necessary, so that after sterilization the solution will have a pH of 
7.3 ± 0.2.  
G.4.2 Filter, if necessary, to clarify,  distribute into suitable vessels and sterilize using a validated 
process. Store at a temperature between 2 °C and 25 °C in a sterile well -closed container, unless it is 
intended for immediate use. Do not use the medium for a longer storage period than has  been validated. 
Soya -bean casein digest medium is to be incubated at 20 °C - 25 °C.  
G. 4.3 The media used shall comply with G.6, carried out before or in parallel with the test on the 
product to be examined.  DUS 706: 2021  
 
© UNBS 2021  – All rights  reserved  21 
 
 G.5 Sterility  
Incubate portions of the media for 14 days. No growth of micro -organisms occurs .  
G.6 Growth promotion test of aerobes, anaerobes, and fungi  
G.6.1 Test each lot of ready -prepared medium and each batch of medium prepared either from dehydrated 
medium or from ingredients. Suitable strains of microorganisms are indicated in Table G.1.  
G.6.2 Inoculate portions of fluid thioglycollate medium with a small number (not more than 100 cfu) of the 
following  microorganisms: using a separate portion of medium for each o f the following species of 
microorganism, Clostridium sporogenes , Pseudomonas aeruginosa , and Staphylococcus aureus.  Inoculate 
portions of alternative thioglycollate medium with a small number (not more than 100 cfu) of Clostridium 
sporogenes .F. Inoculate portions of soy -bean casein.  
G.6.3 Digest the medium with a small number (not more than 100 cfu) of the following microorganisms, 
using a separate portion of medium for each of the following species of microorganism, Aspergillus 
brasiliensis , Bacillus subti lis, and Candida albicans . Incubate for not more than three days in the case of 
bacteria and not more than five days in the case of fungi.  
G.6.4 Seed lot culture maintenance techniques (seed -lot systems) are used so that the viable 
microorganisms used for inoculation are not more than five passages removed from the original master seed 
lot. The media are suitable if a clearly visible growth of the microorganisms occurs.  
Table G.1 —Strains of the test microorganisms suitable for use in the growth promotion te st 
Test microorganisms  
Aerobic bacteria  Fungi  Anaerobic bacterium  
 Staphylococcus aureus  ATCC 6538, 
CIP 4.83, NCTC10788, NCIMB 9518, 
NBRC 13276  
 Bacillus subtilis  ATCC 6633, CIP 
52.62, NCIMB 8054, NBRC 3134  
 Pseudomonas aeruginosaa ATCC 
9027, NCIMB 8626, CIP 82.118, 
NBRC 13275  Candida albicans  ATCC 10231, IP 
48.72, NCPF 3179, NBRC 1594  Clostridium sporogenesb ATCC 
19404, CIP 79.3, NCTC 532 or ATCC 
11437, NBRC 14293  
a An alternative microorganism is Kocuria rhizophila  (Micrococcus luteus ) ATCC 9341.  
b An alternative to Clostridi um sporogenes , when a nonspore -forming microorganism is desired, is Bacteroides 
vulgatus  (ATCC 8482) . 
 DUS 706: 2021  
22 © UNBS 2021  – All rights reserved  
 
 Bibliography  
[1] US 706: 2011,  Non-woven surgical dressings — Specification  
[2] US 2276:2020, Medical c otton swabs - Specification   DUS 706: 2021  
© UNBS 2021  – All rights reserved  23 
 
 Certification marking  
Products that conform to Uganda standards may be marked with Uganda National Bureau of Standards 
(UNBS) Certification Mark shown in the figure below.  
The use of the UNBS Certification Mark is governed by the Standards Act, and the Regulations made 
thereunder. This mark can be used only by those licensed under the certification mark scheme operated by 
the Uganda National Bureau of Standards and in conjunction with the relevant Uganda Standard. The 
presence of this mark on a product or in relation to a product is an assurance that the goods comply with the 
requirements of that standard under a system of supervision, control and testing in accordance with the 
certification mark scheme of the Uganda National Bu reau 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.  
 
 DUS 706: 2021    
 
ICS 11.040.30  
Price based on nn pages  
© UNBS 2021 – All rights reserved