Reference number  
DRS 393 -8: 2018  
© RSB 2018  
 
 
 RWANDA 
STANDARD  DRS  
393-8 
 
First edition  
2018 -mm-dd 
 
Spatial application mosquito repellents — 
Specification  — 
Part 8: 
Liquid detergent s for hard surface 
cleaning  DRS  393-8:2018  
In order to match with technological development and to keep con tinuous progress in industries, Standards are 
subject to periodic review. Users shall ascertain that they are in possession of the latest edition  
 
© RSB 2018  
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 RSB. 
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  
 
 
ii Error! Reference source not found.  
   DRS 393 -8: 2018  
iii                ©RSB 2018 - 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 2018  
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 393 -8: 2018  
©RSB 2018 - All rights reserved                  iv 
 Contents  Page 
Foreword  ................................ ................................ ................................ ................................ .................  viv 
1 Scope  ................................ ................................ ................................ ................................ ............  1 
2 Normative references  ................................ ................................ ................................ ..................  1 
3 Terms and definitions  ................................ ................................ ................................ .................  1 
4 Requirements  ................................ ................................ ................................ ...............................  3 
4.1 General requirements  ................................ ................................ ................................ ..................  3 
4.2 Active ingredient  ................................ ................................ ................................ ..........................  3 
4.2.1  Natural repellents ................................ ................................ ................................ .........................  3 
4.2.2  Synthetic repellents  ................................ ................................ ................................ .....................  4 
4.3 Specific requirements  ................................ ................................ ................................ .................  5 
4.4 Stability  ................................ ................................ ................................ ................................ .........  5 
4.5 Biological efficacy  ................................ ................................ ................................ .......................  5 
5 Packaging and labelling  ................................ ................................ ................................ ..............  5 
5.1 Packaging  ................................ ................................ ................................ ................................ ..... 5 
5.2 Labelling  ................................ ................................ ................................ ................................ ....... 5 
Annex  A (normative)  Determination of DEET content  ................................ ................................ .........  7 
A.1 General  ................................ ................................ ................................ ................................ ..........  7 
A.2 Apparatus  ................................ ................................ ................................ ................................ ..... 7 
A.3 Preparation of calibration curve ................................ ................................ ................................ . 7 
A.4 Procedure  ................................ ................................ ................................ ................................ ..... 7 
A.5 Calculation  ................................ ................................ ................................ ................................ .... 8 
Annex  B (normative)  Determination of permethrin  ................................ ................................ ..............  9 
B.1 Reagents  ................................ ................................ ................................ ................................ ....... 9 
B.2 Apparatus  ................................ ................................ ................................ ................................ ..... 9 
B.3 Operating conditions  ................................ ................................ ................................ ...................  9 
B.4 Procedure  ................................ ................................ ................................ ................................ ..... 9 
B.5 Calculation  ................................ ................................ ................................ ................................ .. 10 
 DRS 393 -8: 2018  
v                ©RSB 2018 - 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 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 393 -8 was prepared by Technical Committee RSB/TC 015, Pharmaceutical Products . 
DRS 393  consists of the following parts, under the general title : Spatial a pplication mosquito repellent s— 
Specification : 
 Part 1: Coils  
 Part 2: Spray  
Part 3: Candles  
Part 4: Papers  
Part 5: Liquid vaporizers  
Part 6: Matt vaporizers  
Part 7: Tablets  
Part 8: Liquid detergents  
Committee membership  
The following organizations were represented on the Technical Committee on Pharmaceutical products 
(RSB/TC 015) in the preparation of this standard.  
National Industrial Research and Development Agency (NIRDA)  
National Pharmacy Council (NPC)  
University of R wanda/College of Sciences and Technology (UR/CST)  
Pharmacie NOVA  
Rwanda Development Board (RDB)  
AGROPY LTD  DRS 393 -8: 2018  
©RSB 2018 - All rights reserved                  vi 
 IKIREZI NATURAL PRODUCTS  
HORIZON/SOPYRWA  
Rwanda Social Security Board (RSSB)  
Pharmavie  
University of Rwanda/College of Medicine and Health Sciences (UR/CMHS)  
Rwanda Biomedical Center/ Malaria and Other Parasitic Diseases Division  (RBC/MOPDD)  
Society for Family Health  (SFH) – Rwanda  
Rwanda Biomedical Center/Medical Procurement and Production Division (RBC/MPPD)  
Institut d’Enseignement Superieur (INES) - RUHENGERI  
Rwanda  Standards Board  (RSB) – Secretariat  DRS 393 -8: 2018  
vii                ©RSB 2018 - All rights reserved  
 Introduction  
Insecticides are used either for killing or controlling harmful insects. The insecticides which are applied for 
repelling insects are termed as “Repellents". Mosquito is one of the most h armful insects for mankind. To destroy 
them, many preparations are available on the market in various recipes like pest killer spray, soap, oil, powder, 
repellent etc. Out of these, mosquito repellent is the most popular as it has germicidal and disinfecta nt properties 
and is able to repel mosquitoes and is convenient to use.  
 
The mosquito repellent is used for warding off mosquitoes which is the most harmful insect. Nowadays, 
mosquito repellents are used for controlling mosquito and are complimenting  other  mosquito destroyers 
gradually. With the rise in the standard of living, increasing urbanization and population, the demand of mosquito 
repellent mat is constantly increasing particularly in tropical places. It is a convenient method for protection 
against  mosquito, so it has a tremendous market potential. Thus there is a very good scope for development of 
such units in the country . 
Spatial repellent are chemical products designed to be 'active' (requiring heat or electricity) or 'passive' (requiring 
no hea t or electricity) and  release volatile chemicals into the air  within the treated space. Product examples that 
are currently available  include mosquito coils, candles among others; however, many more  types of spatial 
repellent products are waiting to be  developed.   
Spatial repellents elicit ‘spatial repellency’ which refers to a range of insect behaviors induced by airborne 
chemicals that result in a reduction in human -mosquito contact.  These behaviors include: movement away from 
a chemical stimulus, attract ion-inhibition and/or, and feeding inhibition.  
 
 DRS 393 -8: 2018  
1                ©RSB 2018 - All rights reserved  
 Spatial application mosquito repellents  — Specification  — Part 8: Liquid 
detergents  for hard surface clean ing 
1 Scope  
This Draft Rwanda S tandard prescribes the requirements , sampling  and test  methods  for liquid detergents for 
hard surface clean ing formulated and prepared as mosquito repellents . 
2 Normative 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 edi tion of the referenced document (including any amendments) applies.  
RS EAS 383, Synthetic organic liquid detergent for household use — Specification  
RS 191, Refined pyrethrum concentrate — Specification  
CIPAC 741, Determination of transfluthrin content  
CIPAC 743 , Determination of prallethrin (etoc) content  
CIPAC 993, Determination of Metofluthrin (S1264)  
CIPAC 742, Determination of d -allethrin  
CIPAC 977, Determination of Meperfluthrin  
CIPAC 760, Determination of picaridin  
DRS 394 -2, Mosquito repellents  — Performance test guidelines — Spatial repellents  
3 Terms and definitions  
For the purposes of this standard , the following terms and definitions apply . 
3.1 
liquid detergent  
product specially formulated for cleaning through the process of detergency.   
©RSB 2018 - All rights reserved                  2 
 3.2 
mosquito  
any of numerous arthropod animals of the class mosquito, having an adult stage characterized by three pairs 
of legs and a body segmented into head, thorax, and abdomen and usually having one or two pairs of wings.  
3.3 
mosquito repellent  
substance  applied to skin, clothing, or other surfaces which discourages mosquito  (and arthropods  in general) 
from landing or cli mbing on that surface  
3.4 
natural repellents/biopesticides  
repellents that contain natural, plant -based active ingredients  
3.5 
synthetic repellents  
conventional repellents containing synthetic chemical active ingredients and carrier synthetic chemical 
comp ounds as approved by a competent authority  conventional . 
3.5 
picaridin  
1-(1-methylpropoxycarbonyl) -2-(2-hydroxyethyl) piperidine or 2 -(2-hydroxyethyl) -1-piperidinecarboxylic acid 1 -
methylpropyl ester  
 
3.6 
transfluthrin  
(1R,3S)-3-(2,2-Dichlorovinyl) -2,2-dimethyl -1-cyclopropanecarboxylic acid (2,3,5,6 -tetrafluorophenyl)methyl 
ester  
3.7 
etoc 
Prallethrin. (S)-2-methyl -4-oxo-3-prop-2-ynylcyclopent -2-enyl(1R) -cis, trans -2,2-dimethyl -3-(2-methylprop -1-
enyl) cyclopropanecarboxylate  DRS 393 -8: 2018  
3                ©RSB 2018 - All rights reserved  
 3.8 
metofluthrin  
C18H20F4O3 , 2,3,5,6-Tetrafluoro -4-(methoxymethyl)benzyl 2,2 -dimethyl -3-(prop -1-en-1-yl) 
cyclopropanecarboxylate  
3.9 
d-Alethrin  
(RS)-3-allyl-2-methyl -4-oxocyclopent -2-enyl (1R) -cis, trans -chrysanthemate  
3.10 
meperfluthrin  
C17H16Cl2F4O3, [2,3,5,6 -tetrafluoro -4-(methoxymethyl)phenyl]methyl (1R,3S) -3-(2,2-dichloroethenyl) -2,2-
dimethylcyclopropane -1-carboxylate  
4 Requirements  
4.1 General  requirements  
4.1.1  The product shall consist of a synthetic organic liquid  detergent that is formulated as mosquito repellent  
and shall be essentially a product which ha s active ingredient (s) added at a certain level.  
4.1.2  The product shall meet all the requirements prescribe d in RS EAS 383.  
4.2 Active ingredient  
4.2.1  Natural repellen ts 
4.2.1.1  Active ingredients used in natural repellents shall be natural plant based active ingredients  such as 
essential oils or any other  plant extract approved as mosquito repellents.  
4.2.1.2 The manufacturer  shall provide adequate data on the repellen ce/efficacy  of such ingredients /product . 
4.2.1.3 The manufacturer  shall have adequate data justifying the proportion of ingredient(s) for which claims 
are made, used in the product.  
4.2.1.4 The essential oils and plant extracts used in natural repellents shall be, but not limited to:  
a) Cedarwood oil ;  
©RSB 2018 - All rights reserved                  4 
 b) Tea tree oil ; 
c) Geranium oil ; 
d) Rosemary oil ; 
e) Lemongrass oil ; 
f) Citronella oil ; 
g) Soybean oil;  
h) Eucalyptus oil ; 
i) Cinnamon oil ; 
j) Neem oil  
4.2.1.5 The proportion of single or blended essential oil  in natural repellent shall be set by the manufacturer in 
accordance with specific standard  (s) of the essential oil used  and records shall be availed.  
4.2.1.6 Pyrethrum extracts such as pyrethrin s shall be considered in natural repellents. The limits of p yrethrin s 
in natural repellents shall not be less than 0.5 %  and the extract used shall meet the requirements of RS 191.     
4.2.2  Synthetic repellents  
4.2.2.1  Synthetic repellents shall contain synthetic chemical compounds which are able to discourage 
mosquitoes and send them flying or crawling away.  
4.2.2.2  If the synthetic chemical compound is blended with other active ingredient (s), either natural or 
synthetic, the proportion shall be set by the manufacturer based on scientific research and records shall be 
availed.  
4.2.2.3  Active ingredients and their content in synthetic repellents shall meet the requirements prescribed in 
table 1.  
Table 1 — Active ingredients content for synthetic repellents  
S/N Active ingredient   Limits  (%, w/w)  Identification method  
1 DEET  5 – 50 Annex A 
2 Permethrin, max  13 Annex B 
3 Transfluthrin , max  1 CIPAC 741  
4 Etoc 0.5 – 1.5 CIPAC 743  
5 Metofluthrin  (S1264) , max  1.82 CIPAC 993  
6 d-Alethrin  (Pynamin Forte), max  5 CIPAC 742  
7 Meperfluthrin, max  0.05 – 0.1 CIPAC 977  
 DRS 393 -8: 2018  
5                ©RSB 2018 - All rights reserved  
 4.2.2.4  Synthetic repellents and their active ingredients shall be approved and registered by competent 
authority.  
4.3 Specific requirements  
The product  shall also co nform to  the specific quality requirements given in Table 2 when tested in accordance 
with t he corresponding test method s. 
Table 2 — Specific requirements  
S/N Parameters  Requirements  Test methods  
1 Solubility in water  Completely soluble  RS EAS 383  
2 Rinsing properties  To pass test  RS EAS 383  
3 pH 6.5 – 11.5 RS EAS 383  
4 Total non detergent organic 
matter, % w/w, max  0.5 RS EAS 383  
 
4.4 Stability  
Stability at elevated temperature . After storage at 54 ± 2ºC for 14 days , the determined average active 
ingredient content shall not be lower than 95 % of the determined average content found before storage and 
the formulation shall continue to co nform to the product requirements.  
4.5 Biological efficacy  
5.5.1  When tested in accordance with DRS 394 -2, the product shall repel 100 % of the mosquitoes available 
in space, within  protectio n time indicated by the manufacturer.  
5.5.2  The protection time of the product shall be indicated on the label.  
5 Packaging and labelling  
5.1 Packaging  
The product shall be pack aged in a suitable, well -closed container, to protect the integrity of the product.  
5.2 Labelling  
The container shall be marked legibly and indelibly with the following information:  
a) name of the product;  
b) manufacturer’s name and physical address;  
NOTE  The name, physical address of the distributor/supplier and trade mark may be added as re quired.  
c) batch  number;   
©RSB 2018 - All rights reserved                  6 
 d) name and strengh of active ingredients;  
e) protection time;  
d) net weight;  
e) country of origin;  
f) directions  for use ; and 
g) manufacture and expiry  dates. 
h) storage conditions  
i) warning and precaution  
 
 DRS 393 -8: 2018  
7                ©RSB 2018 - All rights reserved  
 Annex  A 
(normative)  
 
Determination  of DEET content  
A.1 General  
The sample is dissolved in carbon disulfide and the difference in absorbance at 14.18 µm and at 14.48 µm is 
determined. The quantity of meta -isomer is obtained from this value by means of a calibration curve prepared 
by the use of a reference standard.  
A.2 Apparatus  
F.2.1  Double -beam infrared spectrophotometer. Perkin -Elmer model 21 or equivalent.  
F.2.2  Two equivalent infrared absorption cells, with sodium chloride windows and a path length of 
approximately 0.4 mm.  
A.3 Preparat ion of calibration curve  
F.3.1 Weigh (to the nearest 0.1 mg) into four volumetric flasks sufficient amounts of the reference DEET 
standard of known  purity to give concentrations of approximately 20, 40, 60 and 80 g/L when dissolved in carbon 
disulfide.  
F.3.2 Fill the reference cell with carbon disulfide and the sample cell with each of the standard solutions in 
turn, and record the spectra. The spectrum may be scanned rapidly, except for the region 12 – 15 µm, where a 
normal speed should be used. Carry out a blank measurement with carbon disulfide to correct for any inequality 
in the paired cells and to determine whether a cell correction is required.  
F.3.3 Measure the absorbance at 14.18 µm and at 14.48 µm and calculate the difference between these 
value s, ΔA, for each of the solutions. Plot the values of ΔA against the concentration (g/l) of the meta -isomer.  
 
F.3.4  If a cell correction is required, the value of ΔA is determined from the formula:  
 
  ΔA = [A 14.18 – A14.48]ref. - [A14.48]blank 
 
  Where ref. = determination with reference standard  
    blank = determination on CS 2 blank  
 
A.4 Procedure  
Weigh (to the nearest 0.1 mg) about 0.5 g of the sample, transfer quantitatively to a 10 mL volumetric flask, 
and make up to the mark with carbon disulfide. Measure the infrared absorption at 14.18 μm and 14.48 μm 
using the same conditions as described in section A.3. Determine the con centration of meta -isomer by 
comparing this value with the calibration curve. A standard sample should be run each day to check the 
calibration of the instrument.   
©RSB 2018 - All rights reserved                  8 
 A.5 Calculation  
DEET content (g/kg) =𝐶1 𝑥 𝑃 
𝐶2 
Where,  
 C1 = concentration (g/L) of standard DEET found from calibration curve  
 C2 = concentration (g/L) of sample taken  
   P = purity (g/kg) of the reference standard.  DRS 393 -8: 2018  
9                ©RSB 2018 - All rights reserved  
 Annex  B 
(normative)  
 
Determination of permethrin  
Permethrin as one of t he active ingredient s in this pr oduct may be determined using HPLC by injecting a solution 
of analyte into a chromatograph, followed by separation and comparison of peak areas of the analyte in the 
sample with that of an external standard.  
B.1 Reagents  
Cis – Permethrin, 99%  
Trans - Permethri n, 99%  
Methanol HPLC grade  
Water, HPLC grade  
B.2 Apparatus  
An HPLC equipped with an autosampler, a variable wavelenght detector (or equivalent) and a column 
(phenomena x, 250 x 4.6mm Luna Phenyl 5μ Reverse phase (or equivalent)  
B.3 Operating conditions  
Flow rate  1.0mL/min  
Solvent composition  60% : 40% (Methanol: Water)  
Elution  Isocratic  
Column temperature  40oC  
Wavelength  240nm  
Injection volume  25 μL  
Stop time  50 minutes  
Post time  2 minutes  
 
B.4 Procedure  
B.4.1 Preparation of standard solution  
Weigh about 0.001g (to the nearest 0.0001g) Permethrin standard in beaker, use methanoldissolved and 
transfer them into a separate volumetric flasks (50 ml), dilute to the mark and mix well.  
B.4.2 Preparation of Solution   
©RSB 2018 - All rights reserved                  10 
 Weigh about 0.02 g (to the nearest 0.0001g) Per methrin test sample into beaker, use methanol dissolved and 
transfer them into a separate volumetric flasks (50 ml), dilute to the mark and mix well.  
B.4.3 Determination  
After the chromatograph is stable, make a minimum of three injections of the standard as well as for the sample 
and average the area counts. The relative standard deviation between injections should be within 2%.  
B.5 Calculation  
The % of either cis or trans isomers is calculated as follows;  
%𝑐𝑖𝑠𝑜𝑟𝑡𝑟𝑎𝑛𝑠𝑝𝑒𝑟𝑚𝑒𝑡 ℎ𝑟𝑖𝑛 =𝐴𝑣𝑒𝑟𝑎𝑔 𝑒𝑠𝑎𝑚𝑝𝑙𝑒𝑎𝑟𝑒𝑎 ×𝑤𝑒𝑖𝑔 ℎ𝑡𝑜𝑓𝑠𝑡𝑑 ×𝑝𝑢𝑟𝑖𝑡𝑦 (𝑖𝑛%)
Average  std area  × weight  of sample 
Report the concentration of permethrin as the total of Cis and Trans . DRS 393 -8: 2018  
11                ©RSB 2018 - All rights reserved  
 Bibliography  
[1] Manual on development and use of FAO and WHO specifications for pestic ides, November 2010, 2nd 
Edition.  
[2] Official Methods of Analysis of AOAC International, 19th Edition, 2012, volume I  
 
 DRS 393 -8: 2018  
ICS 65.100  
 
 
©RSB 2018 - All right s reserved