ICS 71.100.35  
 to appear on the last page  
Reference number  
DRS 456 -2: 2021 
© RSB 2021 
  
 RWANDA 
STANDARD  DRS  
456-2 
 
First edition  
Approved by RSB 2021-mm-dd 
 
Surface d isinfectants — Specification  — 
Part 2: 
Disinfectants based on iodophors  
   
DRS 456-2: 2021 
i                ©RSB 2021 - All rights reserved  
  In order to match with technological development and to keep continuous progress in industries, 
standards are subject to periodic review. Users shall ascertain that they are in possession of the latest 
edition 
 
 
 
 
 
 
 
 
© RSB 2021 
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized 
in any form or by any means, electronic or mechanical, including photocopying and microfilm, without 
prior written permission  from R SB. 
Requests for permission to reproduce this document should be addressed to : 
Rwanda Standards  Board  
P.O Box 7099 Kigali -Rwanda  
KK 15 Rd, 49  
Tel. +250 788303492  
Toll Free: 3250  
E-mail: info@rsb.gov.rw  
Website: www.rsb.gov.rw  
ePortal: www.portal.rsb.gov.rw   DRS 456 -2: 2021 
©RSB 2021  - All rights reserved                  ii 
 Contents  Page 
1 Scope  ................................ ................................ ................................ ................................ ............  1 
2 Normative references  ................................ ................................ ................................ ..................  1 
3 Terms and definitions  ................................ ................................ ................................ .................  1 
4 Requirements  ................................ ................................ ................................ ...............................  2 
4.1 Type  ................................ ................................ ................................ ................................ ...............  2 
4.2 Raw materials  ................................ ................................ ................................ ...............................  2 
4.3 General requirements  ................................ ................................ ................................ ..................  2 
4.4 Specific requirements  ................................ ................................ ................................ .................  2 
5 Packaging and labelling  ................................ ................................ ................................ ..............  3 
5.1 Packaging  ................................ ................................ ................................ ................................ ..... 3 
5.2 Labelling  ................................ ................................ ................................ ................................ ....... 3 
6 Sampling  ................................ ................................ ................................ ................................ ....... 4 
6.1 General  ................................ ................................ ................................ ................................ ..........  4 
6.2 Sample for inspect ion ................................ ................................ ................................ .................  4 
6.3 Sample for testing ................................ ................................ ................................ ........................  4 
Annex  A (normative)  Determination of water -insoluble matter content  ................................ ............  6 
A.1 Procedure  ................................ ................................ ................................ ................................ ..... 6 
A.2 Calculation  ................................ ................................ ................................ ................................ .... 6 
Annex  B (normative)  Determination of storage stability  ................................ ................................ ..... 7 
B.1 Reagents  ................................ ................................ ................................ ................................ ....... 7 
B.2 Procedure  ................................ ................................ ................................ ................................ ..... 7 
B.3 Calculation  ................................ ................................ ................................ ................................ .... 7 
B.4 Results  ................................ ................................ ................................ ................................ ..........  8 
Annex  C (normative)  Determination of added colouring matter  ................................ .........................  9 
C.1 Reagent  ................................ ................................ ................................ ................................ .........  9 
C.2 Procedure  ................................ ................................ ................................ ................................ ..... 9 
C.3 Interpretation  of results  ................................ ................................ ................................ ..............  9 
 
 DRS 456-2: 2021 
iii                ©RSB 2021 - All rights reserved  
  Foreword  
Rwanda Standard s are prepared  by Technical Committees and approved by R wanda Standards Board (RSB) 
Board  of Directors in  accordance with the procedures of RSB, in compliance with Annex 3 of the World Trade 
Organisation/Technical Barrier to Trade ( WTO/TBT ) agreement on the preparation, adoption and application of 
standards.  
The main task of technical committees is to prepare  national standards.  Final Draft Rwanda S tandards adopted 
by Technical committ ees are ratified  by me mbers of RSB Board of Director s for publication and gazettment as 
Rwanda Standards.  
DRS 456 -2 was prepared by Technical Committee RSB/TC 024, Organic and Inorganic Chemicals.  
In the preparation of this standard, reference was made to the following standard:  
US 1709 : Disinfectants/sanitizers based on iodophors — Specification  
The assistance de rived from the above source is hereby acknowledged with thanks.  
DRS 456 consists of the following parts, under the general title Surface disinfectants — Specification : 
 Part 1: Disinfectants for general use  
 Part 2: Disinfectants based of iodophors  
Part 3: Disinfectants based on glutaraldehyde  
Committee membership  
The following organizations were represented on the Technical Committee on Organic and Inorganic Chemicals 
(RSB/TC 024) in the preparation of this standard.  
Star Construction and Consultancy Ltd  
Rwanda Inspectorate, Competition and Consumer Protection Auth ority 
Rwanda Food and Drugs Authority  
Rwanda Investigation Bureau  
Rwanda Forensic Laboratory  
Rwanda Social Security Board  
Rwanda Environment Management Authority  DRS 456 -2: 2021 
©RSB 2021  - All rights reserved                  iv 
 BARANYUZWE Cosmetics Ltd  
SULFO Rwanda Industries Ltd  
UBURANGA Natural Products  
Divine Hope Company Ltd  
University of Rwanda /College of Medicine and Health Sciences  
University of Rwanda /College of Sciences and Technology  
University of Rwanda /College of Education  
Rwanda Polytechnic – IPRC Kigali  
Standards for Sustainability (SfS)  
Rwanda  Standards Board  (RSB) – Secretariat  
  DRS 456-2: 2021 
v                ©RSB 2021 - All rights reserved  
   
 DRS 456 -2: 2021  
1                ©RSB 2020  - All rights reserved  
 
 Surface disinfectants  — Specification  — Part 2: Disinfectants based on 
iodophors  
1 Scope  
This Draft Rwanda Standard specifies the requirements, sampling and test methods for disinfectants that 
contain iodophor(s) as active ingredients and are intended for use on inanimate surfaces . It is applicable to all 
disinfectants where iodophors are present.  
2 Norma tive references  
The following documents are 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 (including any amendments) applies.  
EAS 384 , Disinfectants  — Glossary of terms  
ISO 10523 , Water quality — Determination of pH  
DRS 457 , Determination of bacterial efficacy of disinfectants/sanitizers  
3 Terms and definitions  
For th e purposes of this standard, the terms and definitions given in EAS 384 and the following apply.  
3.1 
active ingredient  
any chemical or biological component that is included in the formulation of a disinfectant/sanitizer product in 
sufficient concentration to achieve the intended anti -microbial of the specific product  
 
3.2 
batch  
collection of packages containing a disinfectant/sanitizer of a single type and composition and of a si ngle 
manufactured blend, or of a single delivery.  
3.3 
inanimate surface  
any surface other than live human or live animal tissue (for example, skin)   
©RSB 2021  - All rights reserved                  2 
 
 3.4 
iodophor  
combination of iodine and solubilizing agent (or a “carrier”) that contains (and, when diluted with water, slowly 
liberates) free iodine  
3.5 
lot 
quantity  of disinfectant in sealed containers of the same size and bearing the same batch identification, from 
one manufacturer, submitted at any time for inspection and testing  
4 Requirements  
4.1 Type  
The product shall be of one of the following types:  
Type 1 : without added acid; or  
Type 2 : containing an added acid of an acceptable type.  
4.2 Raw materials  
The product shall not contain ingredients that are recognized as being potentially hazardous or toxic when the 
product is used in accordance the manufacturer’s recommendat ions, nor shall it form toxic or potentially toxic 
reaction products.  
4.3 General requirements  
4.3.1  The product shall not:  
a) leave an objectionable odour on surfaces; and  
b) impart any colour, taste, odour or flavour to food contact surfaces (including drinking wa ter contact 
surfaces) shall not contain perfumes.  
4.3.2  The product intended to be used on food contact surfaces, including drinking water, shall not contain 
perfumes.  
4.4 Specific requirements  
4.4.1  The product shall comply with the requirements given in tabl e 1 when tested i n accordance with the 
test methods specified therein.   
3                ©RSB 2021 - All rights reserved  
  Table 1 — Specific requirements for disinfectants/sanitizers  
S/N Parameters  Requirements  Test methoda 
Type 1  Type 2  
i) Water insoluble matter content, 
g/L, max.  5 5 Annex A 
ii) pH range  4.0 – 7.0 2.0 – 4.0 ISO 10523  
iii) Antimicrobial efficacyb Pass  Pass  DRS 457  
iv) Storage stability  Homogeneous and free -
flowing  Annex B  
v) Added colouring matter  Absent  Annex C 
a The tests shall be carried out at the manufacturer’s prescribed concentration  
b It is recommended that the user assesses the efficacy and suitability of the product for 
specific targeted surfaces under local conditions. 
 
5 Packaging and labelling  
5.1 Packaging   
The container, including the closure, in which the product is packaged shall not interact chemically or physically 
the cont ent and shall be strong enough to protect the product  adequately during normal handling, transportation 
and storage.  
The closure sh all not be made of cork or of any material that contains cork.  
Only packs of the same size and bearing the same batch number shall be packaged together in a bulk pack.  
5.2 Labelling  
The following information shall appear prominently, legibly and indelibly on each container or on a label securely 
attached to each container:  
c) manufacturer’s name or trademark, or both;  
d) name of the product as “disinfectant/sanitizer based on iodophor”;  
NOTE  The product name should not be misleading to the consumer.  
e) nominal volume or mass of the content in metric units;  
f) an indication of the intended use areas for which the product is claimed to be suitable;  
NOTE  Intended use areas may include one or more of the following: general residual settings, industrial/institutional 
settings (such as commercial settings, schools, and offices), hospitals (for non -critical medical devices), food 
processing/food handling areas and equipment, barns/animal housing settings and any other specific area.  
g) general instructions for use. The instructions shall include the recommended concentration, dilution level 
and the minimum exposure period for each purpose;   
©RSB 2021  - All rights reserved                  4 
 
 h) hazard and toxic warnings, where relevant;  
i) statement about the safety precautions to be taken when using the product and the first ait steps to be  
taken in case of direct ingestion or skin contact;  
j) batch number;  
k) production and expiry dates;  
l) adequate draining, rinsing and/or drying requirements from surfaces after use; and  
m) a warning to avoid contact with known incompatible substances, items and foodstuffs.  
NOTE  The manufacturer should substantiate any virucidal claim made about the product  
6 Sampling  
6.1 General  
The following sampling procedure shall be applied in determining whether a lot submitted for  inspection and 
testing complies with the relevant  requirements of this standard. The sample so  drawn shall be deemed to 
represent the lot.  
6.2 Sample for inspection  
After inspecting the lot for compliance with  Clause 4,  take, at random, the number of containers, as  relevant, 
shown in column 2 of Table 2, relative to the appropriate lot size shown in column 1.  
Table 2 — Samples for inspection and testing  
Lot size 
(number of containers) Sample size for ph ysical 
examination 
(number of containers) Sample size for micro biological 
examin ation 
(number of containers) 
0 to 5 000  3 3 
5 001  to 12 5 00 6 3 
12 501 to 25 0 00 9 3 
25 001 to 50 0 00 16 3 
50 001 upwards 30 3 
6.3 Sample for testing  
After inspection of the containers taken in accordance with 6.2, 
a) take, at random, half the number of containers and use them for the storage stability test; and   
5                ©RSB 2021 - All rights reserved  
  b) thoroughly mix the contents of each of the remaining containers and, take from each container the lesser 
of the total volume and 250 mL, and obtain a composite test sample by combining and thoroughly mixing 
these quantities.  Use these samples for testing for compliance with the requirements of Clause 4.  
  
©RSB 2021  - All rights reserved                  6 
 
 Annex  A 
(normative)  
 
Determination of water -insoluble matter content  
A.1 Procedure  
A.1.1  Pipette 5.0 mL of the undiluted disinfectant/sanitizer into a beaker and add 250 mL of standard hard 
water.  
A.1.2  Heat in a steam bath with frequent stirring until the sample is completely dispersed.  
A.1.3  Filter the solution immediately, under suction, through a tarred 1.6 µm glass fibre filter and ensure  that 
the insoluble matter is quantitatively transferred to the filter.  
A.1.4  Allow the solution to drain completely and dry the residue at 105 °C ± 2 °C until constant mass is 
attained. Cool in a desiccator and weigh.  
A.2 Calculation  
The water -insoluble matter content in the solution, expressed in grams  per litre (g/L), shall be calculated using 
the following formula:  
 Water -insoluble matter content = 𝑚
𝑉 
Where,  
 m is the mass, in grams, of the residue after it has been dried; and  
 V is the volume, in litres, of the test solution.  
 
   
7                ©RSB 2021 - All rights reserved  
  Annex  B 
(normative)  
 
Deter mination of storage stability  
B.1 Reagents  
C.1.1  Sodium thiosulphate (Na 2S2O3) solution , 0.02N, accurately standardized.  
C.1.2  Starch solution , 10 g/L  
B.2 Procedure  
B.2.1  Transfer 200 ml of the sample to a 250 -ml stoppered measuring cylinder. Cool to 10 °C ± 1 °C. maintain 
at this temperature for 24h and then examine the test sample visually for signs of separation.  
B.2.2  If visible separation has not occurred, allow the test sample to return to ambient temperature and then 
take from it two test specimens, one fro m near the surface and one from near the bottom of the contents of the 
cylinder.  
B.2.3  Determine the available  iodine content of each of these test specimens as follows:  
Pipette accurately 1 ml of the test specimen into a 250 -ml Erlenmeyer flask, add 100 m l of distilled or 
demineralized water and titrate with the 0.02N sodium thiosulphate solution until a straw coloured titration 
mixture has been reached. Add a small amount of the starch indicator and carry on with the titration until the 
end point at a sta rch indicator colour change, from blue to colourless.  
NOTE  As some iodophors release iodine very slowly as the end point is neared, a reasonable time should be allowed 
before the titration is regarded as completed . 
B.2.4  Repeat the test with another 200 -m test sample. From the stage described in B.2.1, warm and maintain 
the test sample at a temperature of 40 °C ± 1 °C for 24h instead of cooling it.  
B.3 Calculation  
The available iodine content of each of the four test specimens , expressed as a percentage (%), shall be 
calculated using the following formula:  
 Available iodine content = A x N x 126.9  
Where,  
 A is the volume, in millilitres, of the Na 2S2O3 solution use in the titration, and  
 N is the normality of the Na 2S2O3 soluti on.  
©RSB 2021  - All rights reserved                  8 
 
 B.4 Results  
B.4.1  No visible separation shall occur during either the 24h cooling period or 24h warming period, and  
B.4.2  The highest of the four values of the available iodine content (see C.3) shall not differ from the lowest 
by more than 10%.   
9                ©RSB 2021 - All rights reserved  
  Annex  C 
(normativ e) 
 
Determination of added colouring matter  
C.1 Reagent  
Sodium thiosulphate , 50 g/l aqueous solution.  
C.2 Procedure  
Using a pipetted, transfer 5 ml of the test sample to a clean test tube. Using a separate pipette, add 5 ml of the 
sodium thiosulphate solution and mix well.  
C.3 Interpretation of results  
If the colour of the mixture in the tube is no darker than pale straw 30 s after mixing, deem the product to comply 
with 4.4.4.   
©RSB 2021  - All rights reserved                  10 
 
 Bibliography  
[1] ISO/IEC Directives, Part  2, Rules for the structure and drafting of Interna tional Standards , 2016  
[2] ISO/IEC  TR 10000 -1, Information technology  — Framework and taxonomy of International Standardized 
Profiles  — Part 1: General principles and documentation framework  
[3] ISO 10241  (All parts) , Terminological entries in standards