 DRAFT UGANDA STANDARD  
  DUS 926  
Second  Edition  
2021 -mm-dd 
 
 
 Reference number  
DUS 926: 2021  
© UNBS 2021   
  
Chemicals used for treatment of water intended for human use 
— Polyami nes — Specification  
 DUS 926: 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 correct application  
© UNBS 2021   
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilised in any 
form or by any means, electronic or mechanical, including photocopy ing 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 2 50/1/2/3  
Fax: +256 41 4 286 123  
E-mail: info@unbs.go.ug  
Web: www.unbs.go.ug  DUS 926:2021  
© UNBS 2021  – All rights reserved  iii 
 Contents  Page 
Foreword  ................................ ................................ ................................ ................................ .............................  v 
1 Scope  ................................ ................................ ................................ ................................ ......................  1 
2 Normative references  ................................ ................................ ................................ ............................  1 
3 Terms and definitions  ................................ ................................ ................................ ...........................  1 
4 Requirements  ................................ ................................ ................................ ................................ .........  2 
4.1 General requirements  ................................ ................................ ................................ ...........................  2 
4.2 Specific requirements  ................................ ................................ ................................ ...........................  2 
5  Sampling  ................................ ................................ ................................ ................................ ................  2 
5.1  General  ................................ ................................ ................................ ................................ ...................  2 
5.2  Sampling from drums and bottles  ................................ ................................ ................................ ....... 3 
5.2.1   General  ................................ ................................ ................................ ................................ ..................  3 
5.2.2   Surface sampling  ................................ ................................ ................................ ................................ .. 3 
5.2.3  Bottom sampling  ................................ ................................ ................................ ................................ ... 3 
5.3  Sampling from tanks and tankers  ................................ ................................ ................................ ....... 3 
6  Packaging and transportation  ................................ ................................ ................................ ..............  3 
7 Labelling  ................................ ................................ ................................ ................................ .................  4 
7.1  Risk and safety labelling  ................................ ................................ ................................ .....................  4 
7.2 General labelling  ................................ ................................ ................................ ................................ .... 4 
Annex A  (normative)   Determi nation of pH  ................................ ................................ ................................ .... 5 
A.1  General  ................................ ................................ ................................ ................................ ..................  5 
A.2  pH measurement  ................................ ................................ ................................ ................................ .. 5 
Annex B  (normativ e)   Determination of active content  ................................ ................................ ................  6 
B.1  General  ................................ ................................ ................................ ................................ ..................  6 
B.2 Determination of dry solids content  ................................ ................................ ................................ .... 6 
B.2.1  Principle  ................................ ................................ ................................ ................................ .................  6 
B.2.2  Apparatus.  ................................ ................................ ................................ ................................ ..............  6 
B.2.3  Procedure  ................................ ................................ ................................ ................................ ...............  6 
B.2.4  Expression of results  ................................ ................................ ................................ ............................  7 
B.2.5  Precision  ................................ ................................ ................................ ................................ ................  7 
B.3 Determination of salt content.  ................................ ................................ ................................ ..............  7 
B.3.1  Principle  ................................ ................................ ................................ ................................ .................  7 
B.3.2  Apparatus.  ................................ ................................ ................................ ................................ ..............  8 
B.3.3  Procedure  ................................ ................................ ................................ ................................ ...............  8 
B.3.4  Expression of results  ................................ ................................ ................................ ............................  8 
B.3.4  Precision  ................................ ................................ ................................ ................................ ................  8 
Annex C  (normative)   Determination of impurities (epichlorohydrin, 1,3 -dichloro -2-propanol and 
2,3-dichloro -1-propanol) content  ................................ ................................ ................................ ....... 10 
C.1  Principle  ................................ ................................ ................................ ................................ ..............  10 
C.2  Reagents  ................................ ................................ ................................ ................................ ..............  10 
C.2.1   Epichlorohydrin (ECH)  ................................ ................................ ................................ .......................  10 
C.2.2  1,3-dichloro -2-propanol, (1,3 -DCP)  ................................ ................................ ................................ .... 10 
C.2.3  2,3-dichloro -1-propanol , (2,3 -DCP)  ................................ ................................ ................................ .... 10 
C.2.4  Tert-butylmethylether, (TBME)  ................................ ................................ ................................ ...........  10 
C.2.5   ECH standard stock solution, weigh (0.1000 ± 0.0002) g of ECH into a s mall glass sample 
bottle, and make up to (100.0 ± 0.5) g with TBME. Cap the bottle and shake it vigorously 
to mix the contents.  ................................ ................................ ................................ .............................  10 DUS 926: 2021  
iv © UNBS 2021  – All rights  reserved  
 C.2.6  Calibration solution A, weigh (0.1 000 ± 0.0002) g of 1, 3-DCP, (0.1 000 ± 0.0002) g of 2,3 -
DCP and (5.0000 ± 0.0002) g of ECH standard stock solution into a small glass bottle, and 
make up to (50.0 ± 0.2) g with TBME. Cap the bottle and shake it vigorously to mix the 
contents.  ................................ ................................ ................................ ................................ ..............  11 
C.2.7   Calibration solution B, weigh (0.2000 ± 0.0002) g of 1,3 -DCP, (0.2000 ± 0.0002) g of 2,3 -
DCP and (0.5000 ± 0.0002) g of ECH standard stock solution into a small glass bottle, and 
make up to (50.0 ± 0.2) g with TBME. Ca p the bottle and shake it vigorously to mix the 
contents  ................................ ................................ ................................ ................................ ...............  11 
C.2.8   Concentration in calibration solutions, of ECH (C 3), 1,3 -DCP and 2,3 -DCP (C 4) in 
milligrams per kilogram, in calibration soluti ons A and B are calculated as follows:  ................  11 
C.3  Apparatus  ................................ ................................ ................................ ................................ ...........  12 
C.3.1  Ordinary laboratory apparatus and glassware  ................................ ................................ ................  12 
C.3.2   Gas chromatograph, with flame ionization detector (FID) ................................ .............................  12 
C.3.3   Integrator  ................................ ................................ ................................ ................................ ............  12 
C.3.4  Balance, with an accuracy of 0.1 mg  ................................ ................................ ...............................  12 
C.3.5   Column, ultra 2 % to 5 % phenylmethyl silicone, 25 mm x 0.2 mm; film thickness, 0.33 
µm, or equivalent  ................................ ................................ ................................ ................................  12 
C.3.6   Syringe, GC, 10 µL  ................................ ................................ ................................ .............................  12 
C.3.7   Glass bottle, circa 120 mL capacity, with polytetrafluorethylene (PTFE) lined screw caps  ...... 12 
C.3.8   Pipettes, glass, with suitable filling device  ................................ ................................ .....................  12 
C.3.9   Glass vials, 2 mL, with septum crimped or screw cap  ................................ ................................ .. 12 
C.4  Procedure  ................................ ................................ ................................ ................................ ...........  12 
C.4.1   Test portion and sample extraction  ................................ ................................ ................................ . 12 
C.4.2   Analytical procedure  ................................ ................................ ................................ .........................  12 
C.4.3   Retention times  ................................ ................................ ................................ ................................ .. 13 
C.4.4  Sample analysis  ................................ ................................ ................................ ................................ .. 13 
C.4.5   Calibration  ................................ ................................ ................................ ................................ ..........  13 
C.4.6  Blank determination  ................................ ................................ ................................ ...........................  13 
C.5  Expression of results  ................................ ................................ ................................ .........................  13 
C.5.1   Method of calculation  ................................ ................................ ................................ ........................  13 
C.5.2  Precision  ................................ ................................ ................................ ................................ ..............  14 
Annex D  (normative)   Determination of Bulk Brookfield Viscosity.  ................................ .........................  15 
D.1 Apparatus  ................................ ................................ ................................ ................................ ............  15 
D.1.1  Viscometer, Brookfied, Model LVT or equivalent  ................................ ................................ ............  15 
D.1.2  Beaker, 180 ml tall form Griffin or o ther container of equal diameter and depth.  .......................  15 
D.2 Procedure  ................................ ................................ ................................ ................................ ............  15 
D.3 Calculations  ................................ ................................ ................................ ................................ .........  15 
Bibliography  ................................ ................................ ................................ ................................ .....................  16 
 
  
 DUS 926:2021  
© 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 National Enquiry Point on TBT  Agreement  of the World Trade Organisation (WTO).  
The work of preparing Uganda Standards is carried out through Technical Committees. A Technical 
Committee is established to deliberate on standards in a given field or area and consists of key stakeholders 
including government, academia, consumer groups, private sector and other interested parties.  
Draft Uganda Standards adopted by the Technical Committee are widely circulated to stakeholders and the 
general public for comments. The committee reviews the comme nts 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 5, Chemicals and 
environment . 
This second edition can cels and replaces the first edition ( US 926:2012 ), which has been technically revised .  
 DUS 926: 2021  
vi © UNBS 2021  – All rights  reserved  
  Introduction  
Polyamines are used in drinking water treatment to effect coagulation and flocculation of colloidal and fine 
suspended particles and thereby assist the ir removal.  
Polyamines are thus usually utilized in the mainstream processes of clarification and filtration, where they can 
be used as sole flocculants or to supplement the coagulating action of metal salts.  
 DRAFT UGANDA STANDARD  DUS 926: 2021  
 
© UNBS 2021  – All rights reserved  1 
 Chemicals used for treatment of water intende d for human use 
— Polyamin es — Specification  
1 Scope   
This draft Uganda Standard specifies the requirements and methods of sampling and test for polyamines used 
for water treatment intended for human use. 
2 Normative references   
The following referenced do cuments referred to in the text in such a way that some or all of their content 
constitutes requirements of this document. For dated references, only the edition cited applies. For undated 
references, the latest edition of the referenced document (includin g any amendments) applies.  
ISO 3165, Sampling of chemical products for industrial use — Safety in sampling  
ISO 3696, Water for analytical laboratory use — Specification and test methods  
ISO 6206, Chemical products for industrial use — Sampling — Vocabula ry  
ISO 8213, Chemical products for industrial use — Sampling techniques — Solid chemical products in the form 
of particles varying from powders to coarse lumps  
ISO 1392, Determination of crystallizing point — General method  
ISO 3146:2000, Plastics — Deter mination of melting behaviour (melting temperature or melting range) of 
semi -crystalline polymers by capillary tube and polarizing -microscope methods  
ASTM D2879 - 86, Standard Test Method for Vapor Pressure -Temperature Relationship and Initial 
Decompositio n Temperature of Liquids by Isoteniscope  
ASTM E537 - 20, Standard Test Method for Thermal Stability of Chemicals by Differential Scanning 
Calorimetry  
ASTM E1269 – 11, Standard Test Method for Determining Specific Heat Capacity by Differential Scanning 
Calorimetry  
US 1847:2017, Standard Test Methods for Speciﬁc Gravity, Apparent, of Liquid Industrial Chemicals  
3 Terms and definitions   
There are no normative references in this document .  
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  
  
2 © UNBS 2021  – All rights reserved  
  4 Requirements  
4.1 General requirements   
Polyamines  shall be Clear, colourless to amber -coloured liquid. No visible insoluble  gel or extraneous matte r, 
and s oluble with water at all concentrations in all proportions . 
4.2 Specific requirement s 
Polyamines shall conform to the specific requirement s given in  table  1 when tested in accord ance  to the 
methods described therein . 
Table 1— Specific requirements for polyamines   
Parameter  Requirement  Test method  
Specific gravity , at 20°C.  1.16 - 1.24  US 1847:2017  
Vapour pressure , kPa at 20°C  2.4  ASTM D 2879 -86  
Boiling point at 100 kPa   101°C  ASTM E 537 -20  
Freezing point  -7°C  ISO 1392  
Specific heat capacity , kJ/kg  3.13  ASTM E1269 - 11 
pH (undiluted)  4 – 7 Annex A  
Bulk Brookfield Viscosity 
(mPa.s)  70 - 8000  Annex D 
Active content, % (w/w)  30 - 50 Annex B 
Epichlorohydrin, mg/kg of active 
ingredient , max  20  
 
Annex C 1,3-Dichl oro-2-propanol, mg/kg 
of active ingredient, max  1000  
2,3-Dichloro -1-propanol, mg/kg 
of active ingredient, max  500 
NOTE 1 Density of the solution depends on the concentration.  
NOTE 2 Viscosity is dependent on molecular mass and active content  
 
5  Samp ling 
5.1  General  
Sampling shall be carried out in accordance with ISO 3165 and ISO 6206. A representative sample of the 
liquid product, of sufficient mass, shall be obtained immediately after manufacture or from a newly opened 
container(s). The sample sha ll be clearly labelled with product name/code, batch number, type of container(s) 
sampled and date sampled. Reference samples shall be retained for the storage life of the product as claimed 
by the manufacturer/supplier.  DUS 926: 2021  
© UNBS 2021  – All rights reserved  3 
 5.2  Sampling from drums and bottle s  
5.2.1   General  
5.2.1.1   Mix the contents of the container to be sampled by shaking the container or by rolling it or 
rocking it from side to side, taking care not to damage the container or spill any of the liquid.  
5.2.1.2   If the design of the contai ner is such (for example narrow -necked bottle) that it is impracticable to 
use a sampling implement; take a sample by pouring after the contents have been thoroughly mixed. 
Otherwise proceed as described in 5.2.1.3.  
5.2.1.3   Examine the surface of the liqu id. If there no signs of surface contamination, take samples from 
the surface as described 5.2.2; otherwise take samples as described in 5.2.3.  
5.2.2   Surface sampling  
Take a sample using a suitable ladle. Lower the ladle into the liquid until the rim is  just below the surface, so 
that the surface layer runs into it. Withdraw the ladle just before it fills completely and allow any liquid adhering 
to the ladle to drain off. If necessary, repeat this operation so that, when the other selected containers hav e 
been sampled in a similar manner, the total volume of sample required for subsequent analysis is obtained.  
5.2.3  Bottom sampling  
Take a sample using an open sampling tube, or a bottom -valve sampling tube, suited to the size of container 
and the viscos ity of the liquid.  
When using an open sampling tube, close it to the top and the lower the bottom end to the bottom of the 
container. Open the tube and move it rapidly so that the bottom of the tube traverses the bottom of the 
container before the tube is  filled. Close the tube, withdraw it from the container and allow any liquid adhering 
to the outside of the tube to drain off.  
When using a bottom -valve sampling tube, close the valve before lowering the tube into the container and 
then proceed in a simil ar manner to that when using an open sampling tube . 
5.3  Sampling from tanks and tankers  
From each access point, take samples as follows:  
a) from the surface of the liquid, using a ladle as described in 5.2.2;  
b) from the bottom of the tank or tanker, using a sa mpling tube as described in 5.2.3 or using specially 
designed bottom -sampling apparatus; and  
c) from one or more positions, depending on the overall depth, between the bottom and the surface 
using a weighted sampling can.  
6  Packaging and transportation  
The p roduct shall be delivered in suitable containers, for example in bulk containers, drums, cans or bottles.  
In order that the purity of the product is not affected, the means of delivery for bulk containers shall not have 
been used previously for any differe nt product or it shall have been specially cleaned and prepared before 
use. 
  
4 © UNBS 2021  – All rights reserved  
 7 Labelling  
7.1  Risk and safety labelling  
Depending on the toxicity test results of the specific product or on the concentration of active ingredient, 
appropriate R - and S -phrase s shall be assigned to polyamines to warn of possible eye irritant hazard. 
Appropriate risk phrasing shall also be entered on the label or material safety data sheet to the effect that the 
product is slippery. For the general  labelling to be applied to pac kages see 7.2. 
7.2 General labelling  
Each container shall be labelled with at least the following information:  
a)  name of product "POLYAMINE";  
b)  trade name and grade;  
c)  net mass;  
d)  name and address of supplier and/or manufacturer;  
e)  country of or igin; 
f)  storage instructions such as “KEEP AWAY FROM STRONG ACIDS, STRONG OXIDIZING AGENTS 
AND DIRECT SUNLIGHT”;  
g)  date of manufacturing or packaging;  
h)  shelf life; and  
i)  appropriate R - and S -phrases.  
 
 
  
  
 
  DUS 926: 2021  
© UNBS 2021  – All rights reserved  5 
 Annex  A  
(normative)  
 
Determination o f pH 
A.1  General  
Unless otherwise specified all reagents shall be of a recognized analytical grade. The water used shall 
conform to grade 2 specified in ISO 3696.  
A.2  pH measurement  
Measure the pH of the undiluted product, at a temperature of 20 °C, u sing a pH meter. Before making the 
measurement, calibrate the pH meter using at least a buffer solution of pH 4.0 and 7.0  
  
6 © UNBS 2021  – All rights reserved  
 Annex  B  
(normative)  
 
Dete rmination of active content  
B.1  General  
The proportion of active ingredient, that is, polyamine, in a sa mple of product is determined by a procedure in 
which it is assumed that the product is an aqueous solution containing polyamine and inorganic metal salt. 
The active content, expressed as a percentage by mass of polyamine, is given by the formula:  
C0 = C 1 - C2  
where  
C0  is the per cent by mass [% (m/m)] of polyamine;  
C1  is the per cent by mass [% (m/m)] of dry solids; and  
C2  is the per cent by mass [% (m/m)] of inorganic metal salt.  
The results shall be expressed to two decimal places.  
NOTE  The pr ocedure will tend to overestimate the active content slightly if ammonium salts are present in the 
product, as these are lost by volatilization at the ash determining step.  
 
B.2 Determination of dry solids content  
B.2.1  Principle  
The product is heat dried and the mass difference determined gravimentrically.  
B.2.2  Apparatus.  
Ordinary laboratory apparatus and glassware together with the following.  
B.2.2.1  Balance, with an accuracy  of 0.1 mg.  
B.2.2. 2 Oven, capable of maintaining (110 ± 1)oc vented to fume cupb oard.  
B.2.2.3  Desiccator, containing dried silica gel.  
B.2.2.4  Porcelain crucible, 57 mm diameter  
B.2.3  Procedure  
B.2.3.1  Place a porcelain crucible in an oven at 110oc for atleast 10 min.  
B.2.3 .2 Remove the crucible from the oven, place in a desiccator an d allow to cool for atleast 10 min.  DUS 926: 2021  
© UNBS 2021  – All rights reserved  7 
 B.2.3 .3 Weigh the crucible to the nearest 0.1 mg.  
B.2.3 .4 Shake the sample in its container to ensure that it is homogeneous.  
B.2.3 .5 Add 1g to 2g test portion of the product sam ple to the crucible and weigh to the neare st 0.1 mg.  
B.2.3 .6 Place crucible in oven at 110oc for 2 hrs . 
B.2.3 .7 After this time, transfer crucible directly from the oven to desiccator and allow to cool for atleast 
10 min  
B.2.3 .8 Weigh the crucible containing the dry residue to the nearest 0.1 mg.  
B.2.4  Expression of results  
B.2.4.1  Method of calculation  
The dry solids content, C 1, expressed as a percentange by mass of the product, is given by the formula  
 
Where:  
m1 is the mass, in grams of the crucible;  
m2 is the mass, in grams of the crucible and wet sample  
m3 is the mass, in grams of the crucible and dried sample.  
The results shall be expressed to two decimal places.  
B.2.5  Precision  
The absolute difference between two single test results, obtained under repeatability conditions (see note), 
should not be greater than the repeatability value, r, as calculated from the following equation:  
r = 0.05 z  
where;  
z is the mean of two results, expressed in % (m/m).  
NOTE;  Repeatability conditions are where mutually independent test results are obtained wi th the same method on 
identical test material in the same laboratory by the same operator using the same equipment within short intervals of 
time.   
B.3 Determination of salt content . 
B.3.1  Principle  
A known mass of wet sample is dried in accordance with B.2.3 the salt content is then determined 
gravimetrically following ignition of the dry residue in a furnace at 600oc.  
8 © UNBS 2021  – All rights reserved  
 WARNING: Toxic vapours may be released during the ignition of the material. Use a furnace which is vented to a fume 
cupboard.  
B.3.2 Apparat us. 
Ordinary laboratory apparatus and glassware together with the following.  
B.3.2 .1 Balance, with an accuracy of 0.1 mg.  
B.3.2.2 Muffle furnace, capable of maintaining (600 ± 20)oc vented to fume cupboard.  
B.3.2.3  Desiccator, containing dried silica gel.  
B.3.2.4 Oven, capable of maintaining (110 ± 1)oc. 
B.3.3  Procedure  
B.3.3.1  Place the crucible, containing the dry residue in the muffle furnace at 600o C for at least 30 min.  
B.3.3.2  Remove the crucible and place in the oven at 110oC for at  least 30 min, t he place in a desiccator 
until cool and reweigh to the nearest 0.1 mg.  
B.3.4  Expression of results  
B.3.4.1  Method of calculation  
The salt content, C 2, expressed as a percentange by mass of the product, is given by the formula  
 
Where:  
m1 is the mass, in  grams of the crucible;  
m2 is the mass, in grams of the crucible and wet sample  
m4 is the mass, in grams of the crucible and ash sample.  
The results shall be expressed to two decimal places.  
B.3.4  Precision  
The absolute difference between two single test results, obtained under repeatability conditions (see note), 
should not be greater than the repeatability value, r, as calculated from the following equation:  
r = 0. 13 z 
where;  
z is the mean of two results, expressed in % (m/m).  DUS 926: 2021  
© UNBS 2021  – All rights reserved  9 
 NOTE;  Repeatability conditi ons are where mutually independent test results are obtained with the same method on 
identical test material in the same laboratory by the same operator using the same equipment within short intervals of 
time.  
  
10 © UNBS 2021  – All rights reserved  
 Annex C   
(normative)  
 
 Determination of impu rities (epichlorohydrin, 1,3 -dichloro -2-propanol 
and 2,3 -dichloro -1-propanol) content  
C.1  Principle  
Epichlorohydrin, 1,3 -dichloro -2-propanol and 2,3 -dichloro -1-propanol are extracted from the polymer with 
tertbutylmethylether then separated and quantifie d using gas chromatography (GC).  
WARNING :  Epichlorohydrin is flammable with a poisonous vapour. It is toxic by inhalation, skin absorption 
and ingestion and is irritating to the eyes, skin and respiratory system. Eye contact can cause conjunctivitis. It 
can cause cancer. Avoid exposure and keep closed containers in a well -ventilated place.  
1,3-dichloro -2-propanol and 2,3 -dichloro -1-propanol are irritant and by inhalation, skin absorption and 
ingestion. Avoid exposure and keep closed containers in a well -ventilated place.  
Tert-butylmethylether is highly flammable. Keep container tightly closed in a cool, well -ventilated place. Take 
precautions against static electricity discharges. Keep away from sources of ignition. Do not breathe vapour.  
C.2  Reagents  
C.2.1  Epichlorohydrin (ECH)  
C.2.2  1,3-dichloro -2-propanol, (1,3 -DCP)  
C.2.3  2,3-dichloro -1-propanol, (2,3 -DCP)  
C.2.4  Tert-butylmethylether, (TBME)  
NOTE   In respect of C.2.2.2, C.2.2.3 and C.2.2.4 a certificate of analysis giving the assay of the re agent can 
be obtained from the supplier.  
C.2.5  ECH standard stock solution , weigh (0.1000  ± 0.0002) g of ECH into a small glass sample 
bottle, and make up to (100.0  ± 0.5) g with TBME. Cap the bottle and shake it vigorously to mix the 
contents .  
The conc entration of ECH in milligrams per kilogram is calculated as follows:  
C (ECH) = 10 X P  
where  
P  is the assay, expressed as percent by mass [% (m/m)], of ECH.  DUS 926: 2021  
© UNBS 2021  – All rights reserved  11 
 C.2.6  Calibration solution A , weigh (0.1 000 ± 0.0002) g of 1,3 -DCP, (0.1 000 ± 0.0002) g of 2,3-
DCP and (5.0000 ± 0.0002) g of ECH standard stock solution into a small glass bottle, and make up 
to (50.0 ± 0.2) g with TBME. Cap the bottle and shake it vigorously to mix the contents.   
C.2.7  Calibration solution B , weigh (0.2000 ± 0.0002) g of 1,3 -DCP, (0.2000 ± 0.0002) g of 2,3 -
DCP and (0.5000 ± 0.0002) g of ECH standard stock solution into a small glass bottle, and make up 
to (50.0 ± 0.2) g with TBME. Cap the bottle and shake it vigorously to mix the contents  
C.2.8  Concentration in calibration so lutions, of ECH (C 3), 1,3 -DCP and 2,3 -DCP (C 4) in 
milligrams per kilogram, in calibration solutions A and B are calculated as follows :  
C3 = (m x C 5)/50  
where  
m  is the mass, in grams (g), of ECH standard stock solution taken;  
C5  is the concentration, in milligrams per kilogram (mg/kg), of ECH in the Standard stock solution.  
C4 = (m x P)/0.005  
where:  
m  is the mass, in grams (g), of ECH standard stock solution taken;  
P  is the assay, expressed as per cent by mass [% (m/m)] of the DCP.   
12 © UNBS 2021  – All rights reserved  
 C.3  Apparatu s  
C.3.1  Ordinary laboratory apparatus and glassware   
C.3.2  Gas chromatograph, with flame ionization detector (FID)   
C.3.3  Integrator   
C.3.4  Balance, with an accuracy of 0.1 mg   
C.3.5  Column, ultra 2 % to 5 % phenylmethyl silicone, 25 mm x 0.2 mm; fil m thickness, 0.33 µm, or 
equivalent   
C.3.6  Syringe, GC, 10 µL   
C.3.7  Glass bottle, circa 120 mL capacity, with polytetrafluorethylene (PTFE) lined screw caps  
C.3.8  Pipettes, glass, with suitable filling device   
C.3.9  Glass vials, 2 mL, with septum cri mped or screw cap   
C.4  Procedure  
C.4.1  Test portion and sample extraction  
A sample extraction solution is prepared for subsequent GC analysis as follows:  
Weigh test portion of (25.0 ± 0.1) g polymer sample into a clean glass bottle and add (20.0 ± 0.1 ) g of TBME. 
Cap the bottle and, by means of a laboratory shaker, agitate the contents vigorously for 5 min.  
Allow to stand for a few minutes until the two layers have separated.  
Draw off some of the TBME layer with a pipette and transfer to a 2 mL glass  vial for storage in a refrigerator 
until required for analysis  
C.4.2  Analytical procedure  
Instruments settings: sample extraction solutions, calibration and blank solutions are analysed by GC 
apparatus using the following setting and conditions:  
Oven/c olumn temperature: programme: initial 40 °C, hold for 1 min, ramp at 20 °C/min to 140 °C, hold for 4 
min;  
Injector temperature:  250 °C;  
Detector temperature:  300 °C;  
Injection volume:  2 µL;  
Carrier gas:  hydrogen;  
Split vent flow:  50 mL/min;  DUS 926: 2021  
© UNBS 2021  – All rights reserved  13 
 Column he ad pressure:  35 kPa.  
C.4.3  Retention times  
To determine retention times, prepare separate solutions in TBME of ECH, 1,3 -DCP and 2,3 -DCP. Inject with 
a syringe 2 µl of one solution into the gas chromatograph and record the retention time of the resulting  peak. 
Repeat this procedure with the other solutions.   
C.4.4  Sample analysis  
Inject 2  µl of sample extraction solution into the gas chromatograph and with the aid of an electronic 
integrator, measure the areas of the peak of each of three impurities.  
C.4.5  Calibration  
For calibration solutions A and B in turn, inject 2 µl of solution into the gas chromatograph and measure the 
areas of the resulting peaks.  
C.4.6  Blank determination  
Inject 2 µl of TBME solvent into the gas chromatograph obtain a bla nk reading.  
C.5  Expression of results  
C.5.1  Method of calculation  
The contents of ECH, 1, 3 -DCP and 2, 3 -DCP, expressed in milligrams per kilogram of active product, are 
given by the following equation:  
 
where  
Ai  is the peak area of the impurity i n the extraction solution;   
As  is the peak area of the impurity standard;  
C7  is the concentration, in milligrams per kilogram (mg/kg), of the impurity in the calibration solution (C 3 and 
C4); 
mt  is the mass, in grams (g), of TMBE;  
mp  is the mass, in g ram (g), of test portion;  
Co  is the per cent by mass [% (m/m)] of polyamine in the product.  
Thus:  
  
14 © UNBS 2021  – All rights reserved  
 NOTE   The standard solution referred to in the above equation is that which has an impurity peak area closest to that 
of the extraction solution.  
C.5.2  Precision  
The absolute difference between the two single test results, obtained under repeatability conditions (see note 
below), should not be greater than the repeatability value, r, as calculated from the following equation:  
Epichlorohydrin: r = 0.21z  
1,3- and 2,3 -DCP: r = 0.13z  
where  
z  is the mean of the two results, expressed in per cent by mass [%(m/m»).  
NOTE   Repeatability conditions are conditions where mutually independent test results are obtained with same 
method on identical test material in the s ame laboratory by the same operator using the same equipment within a short 
interval of time.  DUS 926: 2021  
© UNBS 2021  – All rights reserved  15 
 Annex D  
(normative)   
 
Determination of Bulk Brookfield Viscosity . 
D.1 Apparatus  
D.1.1  Viscometer, Brookfied, Model LVT or equivalent  
D.1.2  Beaker, 180 ml tall f orm Griffin or other container of equal diameter and depth.  
D.2 Procedure  
D.2.1  Set up the viscometer without the guard attached. Level the instrument.  
D.2.2  Attach the spindle specified by the polyamine supplier. (Note: Left -handed threads.). If no speci fic 
spindle is specified by the manufacturer, start with spindle No.1 and proceed through step 9, and then repeat 
steps 2 through 9, if necessary, with increasing spindle numbers, until a spindle is found that gives a reading 
in step 9 that is in the middl e of the viscometer’s scale range.  
D.2.3 Pour enough sample into the container to cover the spindle up to the groove.  
D.2.4 Adjust the temperature of the sample to 25oC ± 1oC. 
D.2.5 Lower the viscometer with the spindle attached in the sample until the sur face of the sample is at the 
groove on the spindle shaft. The spindle should not contact the bottom of the container.  
D.2.6 Set the viscometer to the chosen rpm.  
D.2.7 Turn on the viscometer motor.  
D.2.8 After the needle reaches a steady reading and after at least 10 revolutions, depress the clutch lever 
on the back of the viscometer to ‘freeze’ the needle on the scale. With the clutch depressed, stop the 
viscometer motor when the needle is visible in the viscometer window.  
D.2.9 Read and record the positio n of the needle on the scale.  
D.2.10 Repeat steps D.2.7 to D.2.9 to obtain three readings.  
D.3 Calculations  
D.3.1  Average the three readings  
D.3.2  Obtain the Brookfield viscosity by multiply the average reading calculated in step 1 by the factor for 
that s pindle and speed supplied by the viscometer manufacturer.  
  
16 © UNBS 2021  – All rights reserved  
 Bibliography  
[1] SANS 51409:2007 , Chemicals used for treatment of water intended for human consumption — 
Polyamines  
[2] US 926: 2012 , Chemicals used for treatment of water intended for human consum ption — Polyamides 
— Specification  
 
  
 DUS 926: 2021  
© UNBS 2021  – All rights reserved  17 
 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 g overned 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. Th e 
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.  
 
 DUS 926: 2021    
 
ICS 71 .100. 80 
Price based on nn pages  
© UNBS 2021 – All rights reserved   
  