FINAL DRAFT UGANDA 
STANDARD  
  FDUS 916
First Edition
2011-mm-dd
 
 
 Reference numbe r
FDUS 916: 2011
© UNBS 2011 
  
Specification for denatured fuel ethanol as used for blending 
with gasoline 
 FDUS 916: 2011 
ii © UNBS 2011 – 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 2010  
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, in cluding photocopying 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: 256 414 505 995 
Fax: 256 414 286 123 
E-mail: unbs@infocom.co.ug  
Web: www.unbs.go.ug  FDUS 916:2011 
© UNBS 2011 – All rights reserved  iii
 Contents Page 
1  Scope ......................................................................................................................... ............................. 1  
2  Normative re ferences .......................................................................................................... .................. 1  
3  Terms and de finitions ......................................................................................................... .................. 2  
4  Quality requirements ............................................................................................................................. 3  
4.1  Physical ...................................................................................................................... ............................ 3  
4.2  Composition ................................................................................................................... ........................ 3  
4.3  Denaturants ................................................................................................................... ......................... 3  
4.3.1 General ....................................................................................................................... ............................ 3  
4.3.2 Prohibited de naturants ........................................................................................................ ................. 3  
5  Packaging and labelling ....................................................................................................... ................ 4  
5.1  Packaging ..................................................................................................................... .......................... 4  
5.2  Labelling ..................................................................................................................... ............................ 4  
6  Sampling ...................................................................................................................... .......................... 4  
6.1  General ....................................................................................................................... ............................ 4  
6.2  Sampling cont ainers ........................................................................................................... .................. 4  
6.3  Sample size ................................................................................................................... ......................... 5  
7  Safety preca utions ............................................................................................................ .................... 5  
A.1 Determination of relative  density (A STM D 1298) .............................................................................. 6 
A.1.1 Apparatus ..................................................................................................................... .......................... 6  
A.1.2 Procedure ..................................................................................................................... .......................... 6  
A.1.3 Calculation ................................................................................................................... .......................... 6  
A.2 Determination of ethanol content .............................................................................................. .......... 7 
A.3 Detection of alkalinity or determinat ion of acidity to phenolphthalein ........................................... 8  
A.3.1 Reagents ...................................................................................................................... .......................... 8  
A.3.2 Procedure ..................................................................................................................... .......................... 9  
A.3.3 Calculation ................................................................................................................... .......................... 9  
A.3.4 Report ........................................................................................................................ ............................. 9  
A.4 Determination of resi due on eva poration ....................................................................................... .... 9 
A.5 Determination of al dehyde content ............................................................................................. ...... 10 
A.5.1 General ................................................................................................................. ................................ 10  
A.5.2 Apparatus ..................................................................................................................... ........................ 10  
A.5.3 Reagents ...................................................................................................................... ........................ 10  
A.5.4 Qualitativ e test .............................................................................................................. ....................... 10  
A.5.5 Quantitative  test ............................................................................................................. ..................... 11  
 FDUS 916: 2011 
iv © UNBS 2011 – All rights reserved
 Foreword 
Uganda National Bureau of Standards (UNBS) is a parastatal under the Ministry  of Tourism, Trade and 
Industry established under Cap 327, of the Laws of Uganda.  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 A limentarius Commission on Food Standards, and  
(c) The National Enquiry Point on TBT/SPS Agr eements 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 gi ven field or area and consists of representatives of 
consumers, traders, academician s, manufacturers, governme nt and other stakeholders. 
Draft Uganda Standards adopted by the Technical Committ ee are widely circulated to stakeholders and the 
general public for comments. The committee reviews the comments before recommending the draft standards 
for approval and declaration as Uganda Standards by the National Standards Council.  
Committee membership 
The following organisations were represented on the Technical Committee for Chemicals and Environment 
Standards UNBS/TC 5, in the pr eparation of this standard:  
• CONSENT 
• Engen (U) Ltd 
• Government Analytical Laboratory 
• Kakira Sugar Limited 
• Kyambogo University, Department of Chemistry 
• Makerere University, College of Agricultural and Environmental Sciences 
• Makerere University, College of Engineering, Design, Art and Technology 
• Makerere University, College of Natu ral Sciences, Department of Chemistry 
• Makerere University, Department of Chemistry 
• Ministry Of Energy and Mineral Development 
• Ministry of Tourism, Trade and Industry 
• National Environmental Management Authority 
• Petrocity Enterprises (U) Ltd 
• Shell (U) Ltd 
• Tapuz Group 
• Tullow Uganda Operations Pty Ltd 
• Uganda Industrial Research Institute  
• Uganda National Bureau of Standards 
• Uganda Revenue Authority 
• Uganda Motor Vehicle Dealers and Importers’ Association  FINAL DRAFT UGANDA STANDARD FDUS 916: 2011
 
© UNBS 2011 – All rights reserved  1
 Specification for denatured fuel ethanol as used for blending 
with gasoline 
1 Scope 
This Final Draft Uganda Standard prescribes the requi rements and the methods of sampling and test for 
anhydrous denatured fuel ethanol intended to be blended with unleaded motor gasoline of premium grade for 
use as a spark-ignition automotive engine fuel.  
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. 
ASTM D 86, Standard test method for distillation of petroleum products at atmospheric pressure 
ASTM E 300, Practice for sampling industrial chemicals  
ASTM D 1152, Standard specification for methanol (methyl alcohol) 
ASTM D 1298, Determination of relative density  
ASTM D 4057, Practice for manual sampling of petroleum and petroleum products  
EAS 640-5: 2008, Petroleum Industry — Terminology — Part 5: Transport, storage and distribution 
ISO Guide 64: 2008, Guide for addressing environmental issues in product standards  
ISO 1388-2: 1981, Ethanol for industrial use- methods of test — Pa rt 2: Detection of alkalinity or determination 
of acidity to phenolphthalein  
ISO 1388-1:1981, Ethanol for industrial use — Methods of test — Part 1: General  
ISO 1388-5:1981, Ethanol for industrial use — Methods of test — Part 5: Determination of aldehyde content- 
visual colorimetric method 
ISO 3170:2004, Petroleum liquids — Manual sampling  
ISO 3171: 1998, Petroleum liquids — Automatic pipeline sampling  
ISO 3864-2: 2004, Graphical symbols- safety colours and safety sign- Part 2: Design principles for product 
safety labels.   
ISO 16104: 2003, Packaging — Transport, packaging for dangerous goods — Test Methods 
ISO 16106, Packaging — transport packages for dangerous goods — Dangerous goods packaging, 
intermediate bulk containers (IBCs) and large packagings — Guidelines for application of ISO 9001:2008  
2 © UNBS 2011 – All rights reserved
 US 933, Gasohol — Specification for E5 and E10 
3 Terms and definitions 
For the purposes of this standard, the following terms and definitions shall apply. 
3.1 
ethanoln- ethyl alcohol, the chemical compound, that is a pure chemical, otherwise known as 
anhydroxyethane corresponding to the constitution CH 3CH 20H 
3.2 anhydrous ethanol (absolute ethanol) 
clear colourless liquid, consisting essentially of pure ethanol containing not more than 0.5 % by volume of water. 
3.3 
denaturant 
substance completely miscible in ethy l alcohol at the concentration used and of such a character that while its 
addition makes the material or any aqueous dilution of  it unpleasant and unwholesome for potable purposes, 
its presence does not render the fuel ethanol, either as such or blended with petrol, unsuitable for use in 
automobile engines 
3.4 
denatured fuel ethanol 
fuel ethanol made unfit for beverage use by addition of  denaturants and meant for use as fuel in automobile 
engines, either as such or after admixture with unle aded petrol (MSP) at the concentration specified by US 
933.. 
3.5 
fuel ethanol 
ethanol with impurities common to its producti on (including water but excluding denaturants) 
3.6 
impurities 
In commercially produced fuel ethanol, compounds other than ethanol or denaturants present, such as methanol and fusel oil (for example amyl, isoamyl alcohols) 
3.7 
relative density 
ratio of the mass of a given volume of the power alc ohol at a specified temperature to the mass of an equal 
volume of distilled water at the same temperature. 
3.8 
batch collection of packages containing a product of a single type and composition of a single manufactured lot, or 
of a single delivery 
NOTE The identified product can be in bulk or packaged. 
3.9 
ullage 
empty capacity left in a fixed volume sample  receiver/ container above the liquid surface FDUS 916: 2011 
© UNBS 2011 – All rights reserved  3
 4 Quality requirements 
4.1 Physical 
The denatured fuel ethanol shall be clear, homogenous li quid and free from matter in suspension. It might be 
coloured with a suitable dye as recommended by the approving authority to distinguish it from alcohol that is 
not for automobile use. 
4.2 Composition 
The material shall consist of anhydrous ethyl alcohol, conforming to the requirements as shown in Table 1. 
Table 1 — Quality requirements for the anhydrous ethanol for power alcohols 
Characteristic Requirement Test method (Annex) 
Relative density at 15 oC, max. 0.7961 A.1 
Relative density at 15 oC , min 0.7936 A.1 
Ethanol content, percent by volume at 
15 oC, min. 99.5 A.2 
Acidity, as acetic acid per cent by mass, max. 0.006 A.3 
Residue on evaporation, percent by mass, max. 0.005 A.4 
Aldehyde content, as CH 3CHO, g/100 
ml, max 0.10 A.5 
 
4.3 Denaturants 
4.3.1 General 
The only denaturants used for fuel ethanol shall be natural gasoline, gasoline components, or unleaded 
gasoline. The use of hydrocarbons with an end boiling point higher than 225 °C as determined by Test 
Method ASTM D 86, as denaturants are prohibited.. Notably are kerosenes, for instance which promote piston 
scuff in automotive engines. It should however be not ed that the denaturant used sh all serve the purpose for 
which it is intended and not deter any of the quality sp ecifications of the denatured fuel ethanol out of the 
indicated limits in Table 1. 
4.3.2 Prohibited denaturants 
Although this specification permits only hydrocarbons in  the gasoline boiling range to be used as denaturants, 
specific mention must be made of some materials that have extremely adverse effects on fuel stability, 
automotive engines, and fuel system s. These materials shall not be used as denaturants for fuel ethanol 
under any circumstances. 
They include methanol which does not meet ASTM D 1152, pyrroles, turpentine, ketones, and tars(high-
molecular weight pyrolysis products of fossil or non fo ssil vegetable matter. the presence of methanol lowers 
the water tolerance and increases the vapor  pressure of a gasoline-ethanol blend.. Also, methanol, which 
does not meet ASTM D 1152, frequently contains impuritie s, such as turpentine and tars. Similarly, ketone 
denaturants tend to degrade fuel stability or increase the tendency of a gasoline-ethanol blend to corrode 
metals and attack elastomers. There is no information available on the effects of  denaturants other than those 
mentioned above; but unless a denaturant, such as a high er aliphatic alcohol or ether, is known to have no 
adverse effect on a gasoline-ethanol blend or on automo tive engines or fuel systems, it shall not be used.  
4 © UNBS 2011 – All rights reserved
 5 Packaging and labelling 
5.1 Packaging 
The alcohol shall be packaged in clean, water-free cont ainers, without dents, made of material which does not 
react with the alcohol and is itself not reacted upon by the alcohol. The  containers shall be sealed so as to 
safeguard the contents from contaminati on and prevent undue losses through evaporation. 
5.2 Labelling 
All containers in which the alcohol is stored or tran sported shall be marked with the following particulars: 
a) name of the product, '’ Denatured fuel ethanol  ”; 
b) name and address of the manufacturer or his trade mark; c) country of origin; 
d) safety label 'FLAMMABLE' together with corr esponding symbols for labelling dangerous goods; 
e) batch number; 
f) certification mark of approved certification body  
Each container shall have a poison label securely affi xed and printed in bold type with red ink showing the 
following information: 
Poison 
'Use only in well-ventilated area' 
'Keep away from heat and open flame' 
'Avoid contact with naked eyes' 
'Avoid contact with the skin 
NOTE Material and Safety Data sheets for the denatured fuel ethanol shall be supplied.' 
6 Sampling 
6.1 General 
To test for the compliance of power alcohol to the requirements of this standard, samples shall be taken 
occasionally from the point of production to various points in the chain of its application. The necessary precautions shall be taken into consideration to guar d the samples from contamination and prevent losses 
from undue evaporation. Samples may be obtained by an appropriate procedure of practice ASTM D 4057 or 
ASTM E 300, except that water displacement (in sect ion on Sampling for Specific Tests in ASTM D 4057) 
must not be used. 
6.2 Sampling containers 
When practical, fuel ethanol shall be sampled in glas s containers. If samples are to be collected in metal 
containers, soldered metal containers shall not be used, because the soldering flux in the containers may contaminate the sample. FDUS 916: 2011 
© UNBS 2011 – All rights reserved  5
 6.3 Sample size 
A minimum of 1 L is recommended. For determination of specific gravity using hydrometer, additional volume 
may be required but this depends on the size of the hydrometer. Leave a minimum of 5 % ullage in the 
container to allow for expansion. 
7 Safety precautions 
Necessary safeguard against the risks arising from the storage, handling and transportation of large volumes 
of the alcohol shall be provided, and all due precautions shall be taken at all times to prevent accident by fire or explosion. 
Except when they are opened for the purpose of cleani ng and rendering them free from alcohol vapour, all 
empty tanks or other containers shall be kept securely  closed unless they have been thoroughly cleansed and 
freed from alcohol vapour.   
To safeguard from injuries resulting fr om splashing or spilling, protective clot hing shall be worn to protect from 
eye or skin irritation or burns. During such potentia l exposures, chemical-type goggles or face shield and 
protective gloves, or combination thereof, must be worn. 
Respiratory protection should be worn, shall be in good condition and must be suitable to protect against 
vapours or spray mist from the power alcohol.   
A second person shall be continuously present to summon help and render aid in the event of an emergency. 
Adequate ventilation shall be ensured while handling the al cohol. Explosion-proof equipment shall be used for 
ventilation, lighting and electrical purposes in spaces wh ere the alcohol is handled. The alcohol shall be kept 
away from open flames, hot surfaces and sources of ignition.   
6 © UNBS 2011 – All rights reserved
 Annex A 
(normative) 
 
Test methods 
A.1 Determination of relative density (ASTM D 1298) 
A.1.1 Apparatus  
A.1.1.1 Hydrometer  - glass type, graduated in units of relative density 
A.1.1.2 Thermometer, with a range of -20 °C to + 102 °C and graduated at intervals of 0.2 °C 
A.1.1.3 Hydrometer cylinder, of clear glass, plastic or metal. T he cylinder may have a lip on the rim. The 
inside diameter of the cylinder shall be at least 25 mm greater than the outside diam eter of the hydrometer 
used in it. The height of the cylinder shall be such that the appropriate hydrometer floats in the sample with at 
least 25 mm clearance between the bottom of the hydrometer and the bottom of the cylinder. 
A.1.1.4 Constant-temperature bath  
A.1.2 Procedure 
Transfer the sample to a clean hydr ometer cylinder without splashing to avoid the formation of air bubbles. 
Place the cylinder containing the sample  in the constant temperature bath maintained at 15 °C and placed in a 
place free from air currents. Place the thermometer into the sample and by stirring the sample slowly by the 
thermometer, ensure that the temperature of the samp le which is 15 °C does not change appreciably during 
the time necessary to complete the test. 
When the sample has attained the test temperature of 15.6 °C, lower the hydrometer gently into the sample, 
taking care to avoid wetting the stem above the level to  which it will be immersed in the sample. Continuously 
stir the sample with the thermometer, taking care that  the mercury thread is kept fully immersed and that the 
stem of the hydrometer is not wetted above the immersion level. As soon as a steady temperature reading is 
obtained, record the temperature of the sample to th e nearest 0.25 °C and then remove the thermometer. 
Depress the hydrometer about two scale divisions into the liquid and then release it. Allow sufficient time for 
the hydrometer to come to rest. When the hydrometer has come to rest, floating freely away from the walls of 
the cylinder, record the hydrometer reading to the nearest 0.000 1 relative density. 
The correct hydrometer reading is that point on the hy drometer scale at which the principal surface of the 
sample cuts the scale. Determine this point by plac ing the eye slightly below the level of the sample and 
slowly raising it until the surface appears to become a straight line cutting the hydrometer scale. 
Immediately after observing the hydrom eter scale value again cautiously st ir the sample with the thermometer 
keeping the mercury thread fully immersed. Record the temperature of the sample to the nearest 0.25 °C. 
Should this temperature differ from the previous readi ng by more than 0.5 °C, repeat  the hydrometer test and 
the thermometer observations until tem perature comes stable within 0.5 °C. 
A.1.3 Calculation 
Apply any relevant corrections to the observed thermome ter reading (for scale or bul b) and to the hydrometer 
reading (scale), and record to the nearest 0.000 1 relative density at the test temperature. FDUS 916: 2011 
© UNBS 2011 – All rights reserved  7
 A.2 Determination of ethanol content 
Determine the relative density of the power alcohol at  15/15 °C according to the method prescribed in A.1 and 
find out the percentage of ethanol by mass and by volume, from Table 2. 
Table 2 — Relations between relative density and percentage of alcohol by mass and by volume  
Relative density in air at 15/15, 
 oC Percentage of alcohol 
By Mass By Volume 
0.7936 100.0 100.00 
0.7937 99.97 99.98 
0.7938 99.93 99.96 
0.7939 99.90 99.94 
0.7930 99.87 99.92 
   
0.7941 99.84 99.90 
0.7942 99.81 99.88 
0.7943 99.77 99.86 
0.7944 99.74 99.84 
0.7945 99.71 99.82 
0.7946 99.68 99.80 
   
0.7947 99.65 99.78 
0.7948 99.61 99.76 
0.7949 99.58 99.74 
0.7950 99.55 99.72 
   
0.7951 99.52 99.70 
0.7952 99.49 99.68 
0.7953 99.45 99.66 
0.7954 99.42 99.64 
0.7955 99.39 99.62 
   
0.7956 99.36 99.60 
0.7957 99.32 99.58 
0.7958 99.29 99.56 
0.7959 99.25 99.54 
0.7960 99.22 99.52 
   
0.7961 99.19 99.50 
0.7962 99.16 99.48 
0.7963 99.12 99.46 
0.7964 99.09 99.44 
0.7965 99.06 99.42 
   
0.7966 99.03 99.40 
0.7967 99.00 99.38 
0.7968 98.96 99.36  
8 © UNBS 2011 – All rights reserved
 0.7969 98.93 99.34 
0.7970 98.90 99.32 
   
0.7971 98.78 99.30 
0.7972 98.84 99.28 
0.7973 98.80 99.26 
0.7974 98.77 99.24 
0.7975 98.74 99.22 
   
0.7976 98.71 99.20 
0.7977 98.67 99.18 
0.7978 98.64 99.16 
0.7979 98.60 99.14 
0.7980 98.57 99.12 
   
0.7981 98.54 99.10 
0.7982 98.51 99.08 
0.7983 98.47 99.06 
0.7984 98.44 99.04 
0.7985 98.41 99.02 
   
0.7986 98.38 99.00 
0.7987 98.34 99.98 
0.7988 98.31 98.95 
0.7989 98.27 98.93 
0.7990 98.24 98.91 
   
0.7991 98.21 98.89 
0.7992 98.18 98.87 
0.7993 98.14 98.85 
0.7994 98.11 98.83 
0.7995 98.08 98.81 
   
0.7996 98.05 98.79 
0.7997 98.01 98.77 
 
A.3 Detection of alkalinity or determi nation of acidity to phenolphthalein 
A.3.1 Reagents 
A.3.1.1  Standardized sodium hydroxide, solution approximately 0.1 M; 
A.3.1.2  Phenolphthalein indicator - Dissolve 0.5 g of phenolphthalein in 100 mL of rectified spirit and 
carefully add the standard sodium hydroxide soluti on till the colour is rendered faintly pink. FDUS 916: 2011 
© UNBS 2011 – All rights reserved  9
 A.3.2 Procedure 
Place 100 mL of distilled water and a fe w pieces of clean porous  pot in a 500-mL conical flask of resistance 
glass, and boil gently for 5 min to eliminate carbon diox ide. Cool slightly and add 100 mL of the alcohol. Boil 
gently for further period of 5 min. At the end of this period, close the neck of  the flask with a stopper carrying a 
soda lime guard tube, and allow to cool. When cool, remove the stopper, add 0.5 mL of phenolphthalein 
indicator and examine for alkalinity; if not alkaline, ti trate with standard sodium hydroxide solution using a 
micro burette. 
Determine the relative density of the power alcohol at  room temperature using hydrometer as prescribed in 
A.1.2. 
A.3.3 Calculation 
Calculate the acidity, if any, in terms of acetic acid and express as percentage by mass of the material taken 
for the test as follows: 
Acidity (as CH 3COOH), per cent by mass = 0.06 VM/S 
where, 
V is the volume, in millilitres, of standard sodi um hydroxide solution required for titration, 
M is the volume morality of standard sodium hydroxide solution, and 
S is the volume relative density of the material at room temperature. 
A.3.4 Report  
Report whether the material is alkaline or acidic. If acidic, report acidity as calculated from A.3.3 
A.4 Determination of residue on evaporation 
Evaporate, on a water bath, 100 mL or more of the materi al to dryness in a weighed,  clean, dry platinum, silica 
or resistance glass dish. Dry the residue for 30 min in  an oven at a temperature of 100 °C ± 2 °C, to a 
constant weight. Cool in a desiccator and weigh. 
Residue on evaporation, per cent by mass = ( m -m1) x 100/ VS 
where, 
m is the mass, in grams of dish and residue after evaporation and cooling, 
m1 is the mass, in grams of empty dish, 
V is the volume, in millilitres, of  the material taken for test, 
S is the relative density of the material de termined at room temperature (see A.1.2).  
10 © UNBS 2011 – All rights reserved
 A.5 Determination of aldehyde content 
A.5.1 General 
For low aldehyde content, a suitable colour reacti on is available when the aldehyde content (as CH 3CHO) is 
expected not to exceed 0.006 per 100 mL of the material. This is based on the resinification that takes place 
and the yellow colour that results on treatment on acetaldehyde with sodium hydroxide. The procedure 
described provides a satisfactory qual itative limit test, but in case of  dispute, the quantitative procedure 
described shall be adopted. In the qualitative proc edure, acetals are also included as aldehydes. 
For higher aldehyde content-materials  containing 0.05 % to 0.5 % of aldehydes, only the quantitative 
procedure described under A.5.4.1 shall be adopted. 
A.5.2 Apparatus 
Stoppered flasks, two, each of 250 mL capacity and identical in shape, size and colour 
A.5.3 Reagents 
A.5.3.1  Sodium hydroxide solution - Dissolve 20 g of sodium hydroxide in water and dilute to 100 m L 
of water. 
A.5.3.2  Stock solution of hydroxylamine hydrochloride - Dissolve 20 g of hydroxylamine 
hydrochloride in 100 mL of water. 
A.5.3.3 Metaphenylenediamine hydrochloride 
A.5.3.4  Aldehyde-free alcohol  - Redistill rectified spirit over solid caustic soda or caustic potash, add 2 g 
to 3 g of metaphenylenediamine several days or under a reflux condenser on a steam bath for several hours 
and distil slowly, rejecting the first 100 mL  and the last 200 mL of the distillate. 
A.5.3.5  Standardized sodium hydroxide solution,  approximately 0.1 M. 
A.5.3.6  Bromophenol blue solution  - Dissolve 0.1 mL of bromophenol blue in 1.5 mL of standard 
sodium hydroxide solution and dilute with water to 2.50 mL. 
A.5.3.7  Hydroxylamine reagent (neutral alcohol solution of hydroxylamine) - Dilute 10 mL of the stock 
solution of hydroxylamine hydrochloride with 100 mL of aldehyde-free alcohol, and 2 mL of bromophenol blue 
solution and then add standard sodium hydroxide solution till the characteristic of dichroic yellowish green 
colour is obtained. 
A.5.4 Qualitative test 
A.5.4.1 Procedure 
Mix 10 mL of the power alcohol with 5 mL of sodium hydroxide solution and set aside for 5 min. 
A.5.4.2 Results 
The limit prescribed for aldehyde content (0.006 g per 100 mL) shall be taken as not having been exceeded if 
no yellow colour is produced in 5 min. FDUS 916: 2011 
© UNBS 2011 – All rights reserved  11
 A.5.5 Quantitative test 
A.5.5.1 Procedure 
Take 50 mL of the material in a flask, add 25 mL of hydroxylamine reagent and 25 mL of distilled water. Allow 
to stand for 15 minutes. Meanwhile prepare a blank in a similar flask by using 25 mL of hydroxylamine reagent 
and 75 mL of distilled water. Titrate this solution until the characteristic dichroic yellowish green colour 
appears. Similarly titrate the sample solution with sta ndard sodium hydroxide solution until the colour matches 
with that of the blank solution. 
A.5.5.2 Calculation 
Aldehyde content (as CH 3CHO), g per 100 mL = 0.08 (V 1 - V2) M 
where, 
V1 is the volume, in millilitres, of standard sodium hydroxide solution required for the titration of the 
sample, 
V2 is the volume, in millilitres, of standard sodium hydroxide solution required, if any, in the blank, and 
M is the morality of standard sodium hydroxide solution. 
 
 FDUS 916: 2010 
© UNBS 2011 – All rights reserved  13
 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 gove rned by the Standards Act, and the Regulations made 
thereunder. This mark can be used only by those licens ed under the certification mark scheme operated by 
the Uganda National Bureau of Standards and in co njunction with the relevant Uganda Standard. The 
presence of this mark on a product or in relation to a product is an assurance that the goods comply with the 
requirements of that standard under a system of supervision, control and  testing in accordance with the 
certification mark scheme of the Uganda National  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.  
 
 FDUS 916: 2011 
 
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