AFRICAN 
STANDARD  DARS  
1476 
First Edition 2018  
 
 Reference No. ARS 1476:2018 (E) 
ICS 71.100.40 
 
 
© ARSO 2018  
  
 
 
 
 
 
 
 
 
 
Acidic liquid toilet cleaners — Specification  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 DARS  1476:2018  
ii © ARSO 2018 — All rights reserved   
Table of contents  
 
1 Scope  ................................ ................................ ................................ ................................ .............  1 
2 Normative refere nces  ................................ ................................ ................................ .....................  1 
3 Definitions and abbreviations  ................................ ................................ ................................ .........  1 
4 Requirements  ................................ ................................ ................................ ................................ . 1 
4.1 General requirements  ................................ ................................ ................................ ............  1 
4.2 Specific quality requirements  ................................ ................................ ................................ . 1 
5 Packaging and marking  ................................ ................................ ................................ ..................  2 
5.1 Packaging  ................................ ................................ ................................ ..............................  2 
5.2 Marking  ................................ ................................ ................................ ................................ .. 2 
Annex A (normative)  Determination of acidity ................................ ................................ ........................  4 
Annex B (normative)  Determination of non -ionic, anionic and cationic surfactant content  ...................  5 
Annex C (normative)  Method for assessing corrosion potential  ................................ ............................  6 
Bibliography  ................................ ................................ ................................ ................................ ............  8 
 DARS 147 6:2018  
© ARSO 2018 — All rights reserved  iii  
Foreword  
 
The African Organization for Standardization (ARS O) is an African intergovernmental organization 
established by the United Nations Econo mic Commission for Africa (UNECA) and the Organization of 
African Unity (AU)  in 1977 . One of the fundamental mandates of ARSO is to develop and harmoniz e 
African Standards (ARS) for the purpose of enhancing Africa’s internal trading capacity, increase 
Africa’s product and service competitiveness globally and uplift the welfare of African communities.  
The work of preparing African  Standards is normally carried out through ARSO  technical committees. 
Each Member State  interested in a subject for which a techni cal committee has been established has 
the right to be represented on that committee. International organizations, Regional Economic 
Communities (RECs), governmental and non -governmental  organizations , in liaison with ARSO , also 
take part in the work.  
 
ARSO Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.  
 
The main task of technical committees is to prepare ARSO  Standards. Draft ARSO  Standards 
adopted by the technical committees are circulated to the member bodie s for voting. Publication as an 
ARSO  Standard requires approval by at least 75 % of the member bodies casting a vote.  
 
Attention is drawn to the possibility that some of the elements of this document may be the subject of 
patent rights. ARSO  shall not be h eld responsible for identifying any or all such patent rights.  
 
This African Standard was prepared by the ARSO Technical Harmonization Committee Number 5 on 
Chemistry and Chemical Engineering (ARSO/THC 05) . 
 
 
 
 
 
© African Organisation for Standardisation  2018 — All rights reserved* 
 
ARSO Central Secretariat  
International House 3rd Floor  
P. O. Box 57363 — 00200 City Square  
NAIROBI, KENYA  
 
Tel. +254 -20-2224561, +254 -20-3311641, +254 -20-3311608  
 
E-mail: arso@arso -oran.org  
Web: www.arso -oran.org  
                                                 
* 2018 ARSO — All rights of exploitation reserved worldwide for African Member States’ NSBs. 
 DARS  1476:2018  
iv © ARSO 2018 — All rights reserved   
 
Copyright notice  
 
This ARSO document is copyright -protected by ARSO. While the reproduction of this document 
by participants in the ARSO standards developm ent process is permitted without prior 
permission from ARSO, neither this document nor any extract from it may be reproduced, stored 
or transmitted in any form for any other purpose without prior written permission from ARSO.  
 
Requests for permission to re produce this document for the purpose of selling it should be 
addressed as shown below or to ARSO’s member body in the country of the requester:  
 
 
© African Organisation for Standardisation 2018 — All rights reserved  
 
ARSO Central Secretariat  
International  House 3rd Floor  
P.O. Box 57363 — 00200 City Square  
NAIROBI, KENYA  
 
Tel: +254 -20-2224561, +254 -20-3311641, +254 -20-3311608  
 
 
E-mail: arso@arso -oran.org  
Web: www.arso -oran.org  
 
Reproduction for sales purposes may be subject to royalty payments or a licensing agreement. 
Violators may be p rosecuted.  
 
 
 
 
 
 DARS 147 6:2018  
© ARSO 2018 — All rights reserved  1  
Acidic liquid toilet cleaners — Specification  
 
 
1 Scope  
 
This African Standard specifies re quirements and methods of test for acidic liquid toilet cleaners. This 
standard applies to a liquid acid, heavy -duty compound suitable for cleaning toilet bowls and urinals.  
 
2 Normative references  
 
The following referenced documents are indispensable for the application 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.  
 
<Text>  
 
3 Definitions  and abbreviations  
 
For the purpose of t his standard the following definition s apply . 
 
toilet cleaner  
product used for cleaning of toilet bowls and urinals  
 
4 Requirements  
 
4.1 General requirements  
 
4.1.1 The product shall be a homogeneous aqueous liquid.  
4.1.2 The product shall be miscible in water in all proportions.  
4.1.3 The product shall be stable, and not deteriorate in storage when kept in its original unopened 
container at ambient temperature for a period stipulated by the manufacturer as the best before date.  
4.1.4 The product shall not  affect toilet bowl and urinal surfaces when used as directed by the 
manufacturer.  
4.2 Specific requirements  
 
4.2.1 The product shall comply with the specific requirements prescribed in Table 1.  
Table 1 ― Specific quality requirements for acid toilet clean er  
S/ No  Characteristic  Requirement  Test method  
Min. Max.  
(i) Total acidity  (expressed 
as HCl) , %, m/m   7 12 Annex A  
(ii) Total surfactant, %, 
m/m 0.4 5 Annex B  
 
4.2.2 The product shall contain an effective rust inhibitor when tested in accordance  with Annex C. 
 
 AFRICAN STANDARD  DARS 147 6:2018  
2 © ARSO 2018 — All rights reserved  5 Packaging and  labelling  
 
5.1 Packaging  
 
5.1.1 The product shall be packed in suitable containers that are securely closed, impervious to the 
product or shall not be corroded by the product, and shall be sufficiently strong to prevent 
contamination of the product arising from the ordinary risks of transportation, handling and storage.  
5.1.2 The lid or cap on the container shall be such that the product is easily and safely dispensed 
from the container.  
5.2 Labelling  
5.2.1 All information m arked on the containers shall be marked in a manner that is conspicuous, 
legible and indelible.  
5.2.2 Each container shall be marked with the following information:  
a) Type  of the product as “acidic toilet cleaner”  
b) manufacturer’s name and physical address  
NOTE The name, physical address of the distributor/supplier and trade mark may be added as required  
c) batch or code number;  
d) net contents;  
e) instruction of use ; 
f) date of manufacture and expiry date; and  
g) country of origin (manufacturer’s name, physical address, and  trade mark (if any) and name 
and physical address of the distributor/supplier if any);  
h) precautionary notice : 
i) the word 'CAUTION' shall be in a colour that contrasts with the surrounding for easy 
visibility and shall be followed with the statement, ‘READ LA BEL BEFORE  USE';  
ii) the following shall be marked immediately under i):  
 'Keep Out of Reach of Children';  
 contains acid, the hazards involved and the necessary storage precautions to be 
used;  
 that, in case of floor spills, baking soda ash shall be sprinkled o ver the product and 
the affected area shall be rinsed with water;  
 the product shall be used for the cleaning of toilet bowls and urinals only;  
 the product shall be marked with the following cautionary words and symbols:  
 ‘CORROSIVE ACID’ ; followed by the sy mbol,  DARS 147 6:2018  
© ARSO 2018 — All rights reserved  3 
 
 ‘DANGER’ ; 
  
 
 DARS 147 6:2018  
4 © ARSO 2018 — All rights reserved   
Annex A  
(normative)  
 
Determination of acidity  
 
 
 
 
Accurately weigh 10 g of sample in a 250 -mL Erlenmeyer flask and add 25 mL of distilled water. Add 
approximately 15 mL of 5 % aqueous calcium ace tate solution and warm contents to 50 °C. Cool and 
filter into beaker.  
 
Carefully rinse the Erlenmeyer flask precipitate with 3 to 4 aliquots of distilled water collecting all 
rinsing with the filtrate. Titrate the filtrate with standard 1 mol/L NaOH solut ion.   
 
Calculate as follows:  
 
percent acidity = 
sampleof massx NaOHofmLx (mol/L) NaOHofion concentrat C  
where  
C = 3.647 for HCI or 
C = 3.132 for H 3PO 4 
 
 
 
 DARS 147 6:2018  
© ARSO 2018 — All rights reserved  5  
Annex B 
(normative)  
 
Determination of non -ionic, anionic and cationic surfactant content  
 
 
 
 
B.1 The molar mass and chemical name of all surfactants used shall be supplied by the 
manufacturer on request by respective partner states bureaux of standards, when use of High 
Pressure Liquid Chromatography (HPLC) equipment is employed in the determination of surfactant 
content in the produ ct. 
B.2 Accurately weigh about 100 g of the product in a 250 -mL Erlenmeyer flask and neutralize it with 
caustic soda solution to a pH of 8.8 to 7.0.  
B.3 Evaporate the resulting solution to dryness at 105 °C. Cool to room temperature and wash the 
resulting solids with five 20 mL aliquots of chloroform, filtering and collecting each in one tared 300 -
mL beaker. Evaporate the chloroform and determine the weight of organic solids, ( W1) g. 
 
productof masssolidsof masssolids Organic1  W
 
NOTE  Myer’s  reagent  may be used to confirm nonioni c surfactant.  Dissolve 100 mg to 150 mg of isolated 
surfactants in 5 mL of distilled water.  Add two drops of Myer’s reagent.  A yellow precipitate will form if non -ionic 
surfactant is present.  
B.4 Dissolve the organic solids in 50 mL of ethanol and pass  resulting solution through a 22 mm x 
200 mm x 250 mm chromatographic column of freshly regenerated cationic exchange resin (150 mm 
to 175 mm mesh). Wash the beaker with four 50 mL aliquots of ethanol collecting them in one tared 
beaker. (Cationic surfacta nt, if present, will be retained, the eluate will contain nonionic and anionic 
surfactants, if present). Evaporate the alcohol eluate in an oven. Weigh accurately, ( W2). 
cationic surfactant, g = W1 – W2 
B.5 Dissolve organic solids ( W2), g obtained in B.4 in 50 mL of ethanol and pass the resulting 
solution through a chromatographic column specified in  B.4 but having freshly regenerated anionic 
exchange resin (150 mm to 175 mm mesh). Wash the beaker with four 50 mL aliquots of alcohol 
collecting them in one t ared beaker.  (Anionic surfactant, if present, will be retained, the eluate will 
contain only nonionic surfactant).  Weigh accurately, W3, g. 
B.6 By difference,  
anionic surfactant content, g = ( W2 – W3) 
surfactant content, percent m/m = 
1003 2 1
mW W W  or 
= 
m2W x 100 %(anionic cleanser)  
 
 DARS 147 6:2018  
6 © ARSO 2018 — All rights reserved   
Annex C 
(normative)  
 
Method for assessing corrosion potential  
 
 
 
C.1 Apparatus  
C.1.1  Squat and tall 1 -L Pyrex glass beakers  
C.1.2  Oven , capable of maintaining 105 °C ± 2 °C  
C.1.3  Test panel , made of stainless steel, of approximate dimensions 125 mm x 63 mm x 1.5 mm. 
The panels shall have a cold -rolled finish on both faces. They shall be undamaged and unmarked, flat 
and with their edges free from burrs.  
C.1.4  Stainless steel tongs , for handling t he panels  
C.1.5  Panel bolders , made of inert material such as polypropylene for use during pre -cleaning and 
drying operations  
C.1.6  Rubber bands , of rectangular cross -section, measuring when lying flat and unstretched, 
approximately 80 mm x 6 mm  
C.1.7  Magn esium carbonate (technical) , for use as an abrasive in cleaning panels  
C.1.8  Distilled water  
C.1.9  Watch glass , large enough to cover the tall 1 -L beakers in C1.1  
C.2 Pre-cleaning of test panels and rubber bands  
C.2.1  Panels  
C.2.1.1  Swab the test panels, t wo for each test, with cotton wool using a warm 1 % v/v solution of 
a general purpose detergent.  
C.2.1.2  Scour the panels with cotton wool using water as a lubricant and the magnesium 
carbonate as an abrasive .  
NOTE  Scouring also removes any films produced  by reaction between the detergent and the abrasive, for example, 
magnesium silicate.  
C.2.1.3  Without delay, thoroughly rinse the panels under hot tap water, ensuring that all of the 
magnesium carbonate is removed.  
C.2.1.4  Then, rinse the panels in boiling , distilled water immersing each panel in turn in water 
contained in three 1 -L beakers.  
C.2.1.5  Dry in an oven at 105 °C ± 2 °C.  
C.2.1.6  Allow to cool in a dry, dust -free position.  DARS 147 6:2018  
© ARSO 2018 — All rights reserved  7 C.2.2  Rubber bands  
C.2.2.1  Place the rubber bands in a hard -boiling 1 % v/ v solution of a general cleaning detergent 
for 10 min.  
C.2.2.2  Rinse under hot tap water.  
C.2.2.3  Then rinse in distilled water and allow to dry.  
C.3 Procedure  
C.3.1  The procedure shall be carried out in duplicate in accordance with C.3.2 – C.3.9.  
C.3.2  In a tall 1 -L beaker, make up 950 mL of the use dilution of the product under test. Mark the 
level of the solution on the side of the beaker.  
C.3.3  Place two rubber bands around each test panel in the direction of the long axis of the panel, 
ensuring that th e bands are flat against both sides of the panel and that the panel is not touched by 
the fingers.  
C.3.4  Five minutes after placement of the bands, immerse the panels on their ends as upright as 
possible in the test solution, so that there is at least 10 m m of solution above the panels. Note the 
time. Place the watch glasses on the beaker.  
C.3.5  Leave the panels in the test solution for 72 h.  Each morning and evening, top up the solution 
to the mark with distilled water.  
C.3.6  At the end of the 72 h remove  the panels from the test solution, remove the bands and rinse 
the panels under hot, running water.  
C.3.7  Then rinse three times as prescribed in C.2.1.4 . 
C.3.8  Finally, dry the panels in the oven at 105 °C ± 2 °C.  
C.3.9  Examine the panels for:  
a. evidence of  corrosion, and  
b. discolouration.  
NOTE  Pitting is most likely to occur where the rubber band contacts the edges of the panel.  
C.4 Interpretation of results  
If the duplicate panels from the test detergents show the same characteristics, record the results. If  
the duplicates differ, repeat the test using fresh panels.  
C.5 Report  
The product shall be deemed to contain an effective rust inhibitor if no visible corrosion or 
discolouration of the panels has occurred.  
 DARS 147 6:2018  
8 © ARSO 2018 — All rights reserved   
Bibliography  
 
 
Working Group to identify and acknowledge useful literature used in the preparation of this standard.  
 
KS EAS 793 -1:2013, Kenya Standard — Toilet cleansers — Part 1: Acidic liquid toilet cleansers — 
Specification  
 
 
 
 DARS 147 6:2018 
© ARSO 2018 — All rights reserved