DRAFT UGANDA STANDARD  
  DUS 191 
Fourth Edition  
2020 -mm-dd 
 
 
 Reference number  
DUS 191: 2020 
© UNBS 2020   
  
Petroleum jelly  — Specification  
 DUS 191: 2020  
ii © UNBS 2020  – 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 applicat ion 
© UNB S 2020   
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 photocopying and microfilm, without prior written 
permission from U NBS.  
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 191:2020  
© UNBS 2020  – All rights reserved  iii 
 Contents  Page 
Foreword  ................................ ................................ ................................ ................................ .............................  v 
1 Scope  ................................ ................................ ................................ ................................ ......................  1 
2 Normative references  ................................ ................................ ................................ ............................  1 
3 Terms and definitions  ................................ ................................ ................................ ...........................  1 
4 Description  ................................ ................................ ................................ ................................ .............  1 
5 Requirements  ................................ ................................ ................................ ................................ .........  2 
5.1 General requirements  ................................ ................................ ................................ ...........................  2 
5.2 Specific requirements  ................................ ................................ ................................ ...........................  2 
5.3 Heavy metal contaminants  ................................ ................................ ................................ ...................  2 
6 Packaging  ................................ ................................ ................................ ................................ ...............  3 
7 Labelling  ................................ ................................ ................................ ................................ .................  3 
8 Sampling and sample preparation  ................................ ................................ ................................ ....... 4 
Annex  A (normative)  Determination of kinematic viscosity  ................................ ................................ .........  5 
A.1 General  ................................ ................................ ................................ ................................ ...................  5 
A.2 Quality of reagents  ................................ ................................ ................................ ................................  5 
A.3 Apparatus  ................................ ................................ ................................ ................................ ...............  5 
A.4 Proce dure  ................................ ................................ ................................ ................................ ...............  5 
Annex  B (normative)  Determination of melting point  ................................ ................................ ....................  6 
Annex C (normative)  Determination of specific gravity  ................................ ................................ ................  7 
C.1 Apparatus  ................................ ................................ ................................ ................................ ...............  7 
C.2 Procedure  ................................ ................................ ................................ ................................ ...............  7 
C.3 Calculation  ................................ ................................ ................................ ................................ .............  7 
Annex D (normative)  Determination of acidity and alkalinity  ........................... Error! Bookmark not defined.  
D.1 Reagents  ................................ ................................ ................................ ....Error! Bookmark not defined.  
D.2 Procedure  ................................ ................................ ................................ ...Error! Bookmark not defined.  
D.3 Results  ................................ ................................ ................................ ........ Error! Bookmark not defined.  
Annex E (normative)  Determination of saponifiable matter  ................................ ................................ ..........  8 
E.1 Reagents  ................................ ................................ ................................ ................................ ................  8 
E.2 Procedure  ................................ ................................ ................................ ................................ ...............  8 
Annex F (normative)  Determination of organic acids  ................................ ................................ ....................  9 
F.1 Reagents  ................................ ................................ ................................ ................................ ................  9 
F.2 Procedure  ................................ ................................ ................................ ................................ ...............  9 
Annex G (normative)  Determination of sulphated ash  ................................ ................................ ................  10 
G.1 Reagents  ................................ ................................ ................................ ................................ ..............  10 
G.2 Procedure  ................................ ................................ ................................ ................................ .............  10 
G.3 Calculation  ................................ ................................ ................................ ................................ ...........  10 
Annex H (normative)  Determination of sulphur and sulphides  ................................ ................................ .. 11 
H.1 Reagents  ................................ ................................ ................................ ................................ ..............  11 
H.2 Procedure  ................................ ................................ ................................ ................................ .............  11 
Annex I (normative)  Determination of iodine value  ................................ ................................ .....................  12 
I.1 Apparatus  ................................ ................................ ................................ ................................ .............  12 
I.2 Reagents  ................................ ................................ ................................ ................................ ..............  12 
I.3 Procedure  ................................ ................................ ................................ ................................ .............  13 
I.4 Calculation  ................................ ................................ ................................ ................................ ...........  13 DUS 191: 2020  
iv © UNBS 2020  – All rights reserved  
 Annex J (normative)  Determination of light ab sorption  ................................ ................................ .............  14 
J.1 Apparatus  ................................ ................................ ................................ ................................ ............  14 
J.2 Procedure  ................................ ................................ ................................ ................................ ............  14 
Annex K (normative)  Det ermination of volatile matter  ................................ ..... Error! Bookmark not defined.  
K.1 Outline of the method  ................................ ................................ ...............  Error! Bookmark not defined.  
K.2 Apparatus  ................................ ................................ ................................ .. Error! Bookmark not defined.  
K.3 Procedure  ................................ ................................ ................................ .. Error! Bookmark not defined.  
K.4 Calculation and report  ................................ ................................ ..............  Error! Bookmark not defined.  
Annex L (normative)   Sampling of petroleum jelly  ................................ ................................ ......................  15 
L.1 General requirements of sampling  ................................ ................................ ................................ ... 15 
M.2 Scale of sampling  ................................ ................................ ................................ ...............................  15 
M.3 Test samples and referee  sample  ................................ ................................ ................................ ..... 16 
M.4 Number of tests  ................................ ................................ ................................ ................................ ... 16 
M.5 Criteria for conformity  ................................ ................................ ................................ ........................  16 
Bibli ography  ................................ ................................ ................................ ................................ .....................  17 
 DUS 191:2020  
© UNBS 2020  – 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 T rade 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, aca demia, 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 comments before recommendin g 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 , Subcommittee SC 1, Industrial and public heal th chemicals.  
This second  edition cancels and replaces the first  edition ( US 191:2020 ), which has been technically revised.  
 DRAFT UGANDA STANDARD  DUS 191: 2020  
 
© UNBS 2020  – All righ ts reserved  1 
 Petroleum jelly  — Specification  
1 Scope   
This Draft Uganda Standard specifies the requirements, sampling and test method s for petroleum  jelly. This 
standard does not cover petroleum jelly for industrial use . 
2 Normative references   
The following referenced documents referred to in the text in  such a way that some or all of their content 
constitutes require ments 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 D217 -10, Standard Test Methods for Cone Penetration of Lubricating Grease  
US EAS 123, Distilled water — Specification    
US EAS 346, Labelling of cosmetics — General requirements   
US EAS 377 -2, Cosmetics and cosmetic products — Part 2: List of substances which cosmetic products must 
not contain except subject to the restri ctions laid down    
US EAS 377 -3, Cosmetics and cosmetic products — Part 3: List of colorants allowed in cosmetic products   
US EAS 847 -16, Cosmetics —Analytical methods —Part 16: Determination of lead, mercury and arsenic 
content  
US ISO 2137 , Petroleum  products and lubricants — Determination of cone penetration of lubricating greases 
and petrolatum  
US ISO 21149, Cosmetics --Microbiolog y --Enumeration and detection of aerobic mesophilic bacteria  
3 Terms and definitions   
No terms and definitions are listed in this document. ISO and IEC maintain terminological databases for use in 
standardization at th e following addresses:  
— ISO Online browsing platform: available at http://www.iso.org/obp  
4 Description  
Petroleum jelly is a translucent, soft mass, greasy to touch and it retains these characteristics on storage. I t 
may contain fragrances or herbal extracts/powder.  DUS 191: 2020  
2 © UNBS 2020  – All rights  reserved  
 5 Requirements  
5.1 General requirements  
5.1.1  All the ingredients used shall comply with the requirements in US EAS 377 -2 and US EAS 377 -3.  
5.1.2  Petroleum jelly shall:  
a) be insoluble in water and ethano l (96 %), but soluble in diethyl ether, dichloromethane, benzene, 
carbon disulphide, hexane and chloroform;  
b) be not of an objectionable odour at room temperature when rubbed on the skin; and  
c) not bleed under normal conditions of storage.  
5.1.3  Petroleum j elly may be coloured using substances complying with US EAS 377 -2 and US EAS 377 -3. 
5.2 Specific requirements  
Petroleum jelly shall comply with the requirements given in Table 1  when tested in accordance with the test 
method specified therein . 
Table 1 — Specific requirements of petroleum jelly  
Characteristic  Requirement  Test method  
Pure  Herbal  Perfumed  
Kinematic viscosity at 
100 °C, Cst  4 - 6.8 4 - 6.8 4 - 6.8 Annex A  
Melting point, °C  46 – 60 46 – 60 46 – 60 Annex B  
Specific gravity at 60 
°C, g/cm3 0.815 - 0.880  0.815 - 0.880  0.815 - 0.880  Annex C  
Saponifiable matter  Nil Nil Nil Annex D 
Organic acids , Max  1ml  1ml 1ml Annex E 
Sulphated ash, % by 
mass, max.  Not greater than 0.10 Not greater than 0.2 Not greater than 0.1 5 Annex F 
Sulphur and 
sulphides  To pass the test  To pass the test  To pass the test  Annex G 
Iodine Value (Wijs) , 
max.  1.5 1.5 1.5 Annex H 
Light absorption of 
0.005 % w/v solution 
in 2,2,4 -
trimethylpentane at 
290 nm, max.  Not greater than 0.8  Not greater than 0.8  Not greater than 0.8  Annex I 
Cone penetration 
value at 25 °C  100 - 275 1/10 mm in 
checking for consistency 
and hardness of jellies  100 - 275 1/10 mm in 
checking for 
consistency and 
hardness of jellies  100 - 275 1/10 mm in 
checking for 
consistency and 
hardness of jellies  US ISO 2137  
Or 
ASTM D217 -10 
5.3 Heavy metal contaminants  
The products shall comply with the limits for contaminants giv en in Table 2 when tested in accordance with 
the test methods specified therein.  DUS 191: 2020  
© UNBS 2020  – All rights reserved  3 
 Table 2 — limits for heavy metal contaminants  
S/N Heavy metal contaminant * Limit, mg/kg, max  Test method  
I Lead  10 US EAS 847 -16 
Ii Arsenic  2 
Iii Mercury  2 
*The total am ount of heavy metals as lead, mercury and arsenic, in combination, in the finished product shall 
not exceed 10 mg/kg.  
5.4 Microbiological limits  
Herb al petroleum jelly shall comply with the m icrobiologi cal limits given in Table 3  when tested in accordance  
with the test method specified therein.  
Table 3 — Microbiological limits  of herbal petr oleum jelly  
Microorganism  Limit  Test method  
Total viable count, CFU/g or CFU/ml, max.  1000 ISO 21149  
6 Packaging  
Petroleum jelly shall be packaged in securely closed containers that shall  
a) protect,  
b) effectively s creen the content from UV light when stored, and  
c) not cause any contamination or reaction with the pro duct.  
7 Labelling  
In addition to the labelling requirements specified in US EAS 346, the following information shall be indelibly 
and legibly marked on t he container:  
a) product name, that is, “Pure petroleum jelly”, or “Perfumed petroleum jelly” or “Herbal  petroleum jelly ”; 
or “Herbal  perfumed  petroleum jelly ”; 
b) name and physical address of manufacturer, distributor or supplier or trademark;  
c) net content;  
d) lot identification, for example, batc h number in code or otherwise;  
e) date of manufacture in the form  “mm/yyyy” ; 
f) expiry  date i n the form  “mm/yyyy”;  
g) country of origin; and   
h) storage conditions.  DUS 191: 2020  
4 © UNBS 2020  – All rights  reserved  
 8 Sampling and sample preparation  
The method of sampling and preparing representative test samples of the material and the criteria for 
conformity shall be as prescribed in Annex J. DUS 191: 2020  
© UNBS 2020  – All rights reserved  5 
 Annex  A 
(normative)  
 
Determination of kinematic viscosity  
A.1 General  
The kinematic viscosity is determined by using viscometers. The specific details of opera tion vary for different 
types of viscometers.  
A.2 Quality of reagents  
Unless specified otherwise, anal ytical grade reagents and water of distilled quality conforming to US EAS 123 
shall be employed in test.  
A.3 Apparatus  
Capillary viscometer  
A.4 Procedure  
The time is measured for a fixed volume of sample, contained in a glass viscometer, to flow through a  
calibrated capillary under an accurately reproducible head of liquid and at 100 °C. This temperature shall be 
controlled. The viscometer selected should give an efflux time greater than 200 s. The kinematic viscosity is 
calculated from the measured efflux  time. The viscometer is calibrated by using standard oil having viscosities 
established with reference to water in master viscometers or by direct compar ison with carefully calibrated 
viscometers. The temperatures of the bath used shall be maintained with in ± 0.01 °C.  DUS 191: 2020  
6 © UNBS 2020  – All rights  reserved  
 Annex  B 
(normative)  
 
Determination of melting point  
B.1 Melt a quantity of the sample slow ly while stirring until it reaches a temperature of 90 °C - 92 °C. 
Remove the source of heat and allow  the molten sample to cool to a temperature of 8 °C - 10 °C above the 
expected melting point. Chill the bulb of a thermometer (range: 1 °C - 100 °C) to 5 °C, wipe it dry and while it 
is still cold, dip it into molten sample so that approximately half of th e bulb is “submerged". Withdraw it 
immediately and hold it vertically away from heat until the wax surface dulls, then dip it for 5 min into a water 
bath having a temperature not higher than 16 °C.  
B.2 Fix the thermometer prepared B.1 securely in a test t ube so that its lowest point is about 15 mm above 
the bottom of the test tube. Suspend the test tube in a water bath adjusted to 16 °C, and raise the temp erature 
of the bath at a rate of 1 °C/min and note the temperature at which the first drop of the melt ed sample leaves 
the thermometer. Repeat the determination twice on a freshly melted portion of the sample. If the variation in 
three determinations is le ss than one degree take the average of three as the melting point. If the variation in 
the three deter minations is more than one degree, make two additional determinations and take the average 
of the five.  DUS 191: 2020  
© UNBS 2020  – All rights reserved  7 
 Annex C  
(normative)  
 
Determination of specific gr avity  
C.1 Apparatus  
C.1.1  Specific gravity bottle, 25 -mL capacity, with a well - fitting ground glass s topper with a capillary  
C.1.2  Water bath, maintained at 60 °C ± 1 °C  
C.2 Procedure  
C.2.1  Clean and dry the specific gravity bottle, and weigh it. Then f ill it with water, insert the stopper and 
immerse in the water bath at 60 °C ± 1 °C. Keep the entire b ulb completely immersed in water and hold at that 
temperature for 1 h. carefully remove any water which has exuded from the capillary opening. Remove from  
the bath, wipe completely dry, cool to room temperature and weigh.  
C.2.2  Melt approximately 40 g of the material in a porcelain dish and fill the dry specific gravity bottle with it. 
Keep the bottle for 1 h in a water bath at 60 °C ± 1 °C. Carefully remo ve any material which exudes from the 
capillary opening, wipe the bottle dry and cool at room temperat ure and weigh.   
C.3 Calculation  
The specific gravity 60°C/ 60°C for petroleum jelly shall be expressed as follows:  
Specificgravity60°C/60°C=  
  
where  
m1 is the mass, in grams, of specific gravity bottle with the material,  
m2 is the mass, in grams, of the  specific of the gravity bottle, and  
m3 is the mass, in grams, of the specific gravity bottle with water.  DUS 191: 2020  
8 © UNBS 2020  – All rights  reserved  
 Annex D 
(normative)  
 
Determination of saponifiable matter  
D.1 Reagents  
D.1.1 Methyl ethyl ketone, analytical grade, stored in amber coloured bottle  
D.1.2 Standard alcoholic potassium hydroxide solution, 0.5 mol/L standardized before use  
D.1.3 Petroleum ether, boiling range 80 °C - 100 °C  
D.1.4 Standard hydrochloric acid, 0.5 mol/L accurately standardized  
D.1.5 Phenolphthalein indicator solution, 1 % solution in 95 % rectified spirit   
D.2 Proced ure 
D.2.1 Accurately weigh in flask about 5 g of the sample and add 25 ml ± 1 ml of methyl ethyl keton e, 
followed by 25 m l standard alcoholic potassium hydroxide solution from a burette. Connect the flask to a 
condenser and heat for half an hour after refl uxing begins. Disconnect the condenser, add 50 ml of petroleum 
ether and titrate the solution while ho t (without heating) with standard hydrochloric acid, using three drops of 
phenolphthalein indicator. When the indicator colour is discharged add three dro ps more of the indicator. If 
this addition restores the colour, continue the titration. Proceed in thi s manner until the end point is reached 
when the indicator colour is discarded and does not immediately reappear upon the addition of three more 
drops of indicator.  
D.2.2 Run a blank under identical conditions.  
D.2.3 The sample shall be taken to have passe d the requirement specified in Table 1 if the blank reading 
does not differ from the sample reading by more than 0.1 ml.  DUS 191: 2020  
© UNBS 2020  – All rights reserved  9 
 Annex E 
(normative)  
 
Determinatio n of organic acids  
E.1 Reagents  
E.1.1 Dilute rectified spirit, prepared by diluting one volume of 95 %  rectified spirit with two volumes of 
water, and neutralized to phenolphthalein indicator  
E.1.2 Phenolphthalein indicator, same as in D.1. 5  
E.1.3 Standa rd sodium hydroxide solution, exactly 0.1 mol/L  
E.2 Procedure  
E.2.1 Add 100 m l of dilute rectified sp irit to 20 g of the sample, agitate thoroughly, and heat to boiling. Add 1 
mL of phenolphthalein indicator and titrate rapidly with standard sodium hydrox ide solution with vigorous 
agitation to a sharp pink endpoint in the alcohol water layer.  
E.2.2 The m aterial shall be taken to have passed the test if not more than 1 ml of standard sodium 
hydroxide solution is required for the titration.  DUS 191: 2020  
10 © UNBS 2020  – All rights  reserved  
 Annex F 
(norm ative)  
 
Determination of sulphated ash  
F.1 Reagents  
Dilute sulphuric acid, approximately 2.5 mo1/L  
F.2 Procedure  
Heat a platinum dish to redness for 10 min; allow to cool in a desiccator and weigh. Place 1 g of the sample in 
the dish, moisten with sulphur ic acid, and ignite gently by means of a Bunsen burner. Again moisten with 
sulphuric acid and ignite a t about 800 °C in a muffle furnace. Cool and weigh, again ignite for 15 min and 
repeat this procedure until two successive weighings do not differ by more  than 0.5 mg.  
F.3 Calculation  
Sulphated ash, percent by mass for petroleum jelly shall be expressed as follows:  
Sulphated  ash, percent by  mass=  
  
where  
m1 is the mass, in grams, of the residue, and  
m2 is the mass, in grams, of the sample taken for the  test. DUS 191: 2020  
© UNBS 2020  – All rights reserved  11 
 Annex G 
(normative)  
 
Determination of sulphur and sulphides  
G.1 Reagents  
Copper strips, 1 cm in  width, and freshly polished  
G.2 Procedure  
G.2.1 Melt in a beaker about 100 g of the sample and keep on a water bath at a temperature of 95 °C. Then 
place a strip of copper in the melted sample so that it is partially immersed in it and allow to remain fo r 10 min.   
G.2.2 The material shall be taken to have passed the test if the copper strip used in the test shows no 
tarnishing when compared with another freshly polished copper strip.  DUS 191: 2020  
12 © UNBS 2020  – All rights  reserved  
 Annex H 
(normative)  
 
Determination of iodine value  
H.1 Apparatus  
Thermometer, an engraved stem thermometer, calibrated between 10 °C and 65 °C in 0.1 -degree intervals 
and with the 0 °C point marked on the steam is recommend ed. The thermometer shall have an auxiliary 
reservoir at the upper end, and length of about 370 mm and  diameter of about 6 mm.  
H.2 Reagents  
H.2.1 Carbon tetrachloride or chloroform  
H.2.2 Acetic acid, glacial. 99 %, having a melting point of 14.8 °C and f ree from reducing impurities. 
Determine the melting point of the acetic acid as in H.2.2.1 and test it  for reducing impurities as in H.2.2.2.  
H.2.2.1  For the melting point determination, take a 15  cm long test tube and fill it to about two thirds with 
the acetic acid. Insert into the acid a thermometer satisfying the requirements specified in A.10.1 throu gh a 
cork stopper fitting the test tube. The amount of acid should be at least double the quantity required to cover 
the bulb of the thermometer when the bottom of the latter is 12 mm from the bottom of the test tube. Suspend 
this tube within a larger test  tube through a cork. Cool the acid by immersing the assembly in ice water until 
the temperature is 10 °C, then withdraw the assembly from the ice water a nd stir the acid rather vigorously for 
a few moments, thus causing the super -cooled liquid to crystall ize partially and give a mixture of liquid and 
solid acid. Take thermometer readings every 15 s and consider the temperature at which the reading remains 
constant for at least 2 min as the true melting point.  
H.2.2.2  For the determination of reducing impu rities (potassium permanganate test), dilute 2 mL of acetic 
acid with 10 mL of water and add 0.1 mL of 0.5 mol/L potassium permanganate solution and maint ain at 27 °C 
± 2 °C. The test shall be taken as having been satisfied if the pink colour is not discha rged at the end of 2 h.   
H.2.3 Potassium dichromate, finely ground   
H.2.4 Starch solution, mix 5 g of starch and 0.01 g of mercuric iodide with 30 mL of cold water and slowly 
pour it while stirring into 1 L of boiling water. Boil for 3 min. Allow the sol ution to cool and decant off the 
supernatant clear liquid.  
H.2.5 Standard sodium thiosulfate solution, 0.2 mol/L  
H.2.6 Chlorine gas, dry  
H.2.7 Iodine t richloride  
H.2.8 Wijs iodine monochloride solution, prepare this solution by one of the following met hods, and store in 
a glass stoppered bottle in a cool place, protected from light and sealed with paraffin until taken for use:  
a) Dissolve 3 g of re -sublim ed iodine in 1 L of acetic acid, using gentle heat if necessary, and determine 
the length by titration  with standard sodium thiosulfate solution. Set aside 50 m l - 100 m l of solution 
and introduce washed and dried chlorine gas into the remainder until the characteristic colour change 
occurs and the halogen content is nearly doubled as ascertained again by titration. If the halogen 
content has been more than doubled, reduce it by adding the requisite quantity of the iodine - acetic 
acid solution. A slightly excess of iodine does not harm, but avoid an excess of chlorine.  DUS 191: 2020  
© UNBS 2020  – All rights reserved  13 
 For example, if the titration of 20 ml of original iodine acetic acid solution requires 22 m l of standard 
sodium thiosulfate solution then 20 m l of the finished Wijs solution should require between 43 m l and 
44 m l (and not more than 44 m l) of the same sodium thiosulfate.  
b) As an alternative m ethod of preparing Wijs solution, dissolve 8 g of iodine trichloride in approximately 
450 m l of acetic acid. Dissolve separately 9 g of iodine in 450 m l, of acetic acid using heat if 
necessary. Add gradually the iodine solution to the iodine trichloride so lution until the colour has 
changed to reddish brown. Add 50 m l more of iodine solution and dilute the mixture with acetic acid till 
10 m l of the mixture are equivalent to 20 m l standard sodium thiosulfate solution when the halogen 
content is estimated by titration in the presence of an excess to potassium iodine and water. Heat the 
solution at 100 °C for 20 min and cool. Prevent access of water vapour in p reparing the solution.  
H.3 Procedure  
H.3.1 Melt the material and filter through the filter paper to remove any impurities and the last trace of 
moisture. Make sure that the glass apparatus used is absolutely clean and dry. Weigh accurately by 
difference,  about 10 g of the sample, into a clean, dry 500 -ml glass stoppered bottle to which 25 m l of carbon 
tetrachloride or  chloroform have been added, and agitate to dissolve the contents. Add 25 ml of Wijs solution 
(the quantity of Wijs solution added is 50 % - 60% more than the quantity required).  
H.3.2 Replace the glass stopper after wetting with potassium i odine solution, swirl for intimate mixing, and 
allow to stand in the dark for 45 min. Carry out a blank test simultaneously under similar experimental 
conditions. After standing, add 15 ml of potassium iodide solution and 100 ml of water, and titrate the l iberated 
iodine with standard sodium thiosulfate solution, swirling the contents of the bottle continuously to avoid any 
local excess, until the colour of  the solution is straw yellow. Add 0.5 ml of starch solution and continue the 
titration until the blue  colour disappears.  
H.4 Calculation  
The Iodine value of petroleum jelly shall be expressed as follows:  
Iodine value =
  
where  
V1 is the volume, in milli litres, of standard sodium thiosulfate required for the blank,  
V2 is the volume, in millilitres, of s tandard sodium thiosulfate solution required for the material,  
M is the molarity of standard sodium thiosulphate, and  
m is the mass, in grams, of the ma terial taken for the test.  DUS 191: 2020  
14 © UNBS 2020  – All rights  reserved  
 Annex I 
(normative)  
 
Determination of light absorption  
I.1 Apparatus  
UV spe ctrophotometer  
I.2 Procedure  
Make of solution of 0.05 % m/v of the petroleum jelly in 2,2,4 - trimethylpentane, then determine the 
absorbency at 290 nm.  DUS 191: 2020  
© UNBS 2020  – All rights reserved  15 
 Annex J 
(normative)   
 
Sampling of petroleum jelly  
J.1 General requirements of sampling  
J.1.1 In drawing, preparing, storing and handling t est samples the precautions and directions in J.1.2 to 
J.1.8 shall be observed.  
J.1.2 Samples shall n ot be taken in an exposed place.  
J.1.3 The sampling instrument shall be clean and dry.  
J.1.4 Precaution shall be taken to protect the samples, the mater ials being sampled, the sampling 
instrument and the containers or samples from adventitious contaminat ion. 
J.1.5 To draw representative sample, the content of each container selected for sampling shall be mixed as 
thoroughly as possible by suitable means .  
J.1.6 The samples shall be kept in clean dry airtight glass or other suitable containers.  
J.1.7 The sample containers shall be of such a size that they are almost completely filled by the sample.   
J.1.8 Each sample container shall be sealed airtight w ith a suitable stopper after filling, and marked with full 
details of sampling, the date of sampling a nd the year of manufacture of the material.  
J.2 Scale of sampling  
J.2.1 All the containers in a single consignment of the material drawn from a single ba tch of manufacture 
shall constitute a lot. If a consignment is declared or known to consist of differe nt batches of manufacture, the 
containers belonging to the same batch shall be grouped together and each such group shall constitute a 
separate lot.  
J.2.2 Samples shall be tested from each lot for ascertaining conformity of the material to the requirement  of 
this specification . 
J.2.3 The number of containers (n) to be chosen from the lot shall depend on the size of the lot (N) and 
shall be as given in Tab le J.1.  
J.2.4 The containers to be selected for sampling shall be chosen at random from the lot and f or this 
purpose, random number tables shall be used. In case such tables are not available, the following procedure 
may be adopted:  
Starting from any con tainer count 1, 2, 3, r and so on in a systematic manner, where r is the integral part of 
N/n. Every r th container thus counted shall be withdrawn from the lot.  DUS 191: 2020  
16 © UNBS 2020  – All rights  reserved  
 Table J.1 — Number of containers to be selected for sampling  
Lot size, N  Number of containers to be selected, n  
3 – 5 3 
51 – 200 4 
201 – 400 5 
401 – 650 6 
Greater than 650  7 
J.3 Test samples  and referee sample  
Preparation of test samples  
J.3.1 Draw with an appropriate sampling instrument a small portion of the material from different pans of 
each container selected (see Table J.1). The total quantity of the material drawn from each container shall be 
sufficient to conduct the tests for all the characteristics given in Clause4 and shall not be less than 250 g.  
J.3.2 Thoroughly mix all portions  of the material drawn from the same container. Out of these portions, 
equal quantities shall be taken  from each selected container and shall be well mixed up together so as to form 
a composite sample weighing not less than 0.5 kg. This composite sample sh all be divided into three equal 
parts, one for the purchaser, the supplier and the third for the refer ee shall be used in case of dispute between 
the two.   
J.4 Number of tests  
Tests for all the characteristics given in Table 1 shall be conducted on the co mposite sample.  
J.5 Criteria for conformity  
A lot shall be declared as conforming to this specificati on if the composite sample satisfies the requirements 
for each of the characteristics listed in Table 1. If the requirements for any of the characteristic s are not met, 
the lot shall be declared to have not satisfied the requirements of the specification.  DUS 191: 2020  
© UNBS 2020  – All rights reserved  17 
 Bibliography  
[1] TZS 318: 1999 , Petroleum jelly , (Part 1): Petroleum jelly for cosmetic industry - Specification  
[2] TZS 3 18: 1999 , Petroleum jel ly, (Part 2): Marketed petroleum jelly products ready for use as a body 
ointment  
[3] US 191:2016, Petroleum jelly  — Specification  
[4] US ISO17516 : 2014,  Cosmetics — Microbiology — Microbiological limits  
 
 WDUS 191: 2020  
© UNBS 2020  – All righ ts reserved  19 
 Certification marking  
Products that conform to Uganda standards may be marked with Uganda Nati onal Bureau of Standards 
(UNBS) Certification Mark shown in the figure below.  
The use of the UNBS Cer tification Mark is governed by the Standards Act, and the Regulations made 
thereunder. This mark can be used only by those licensed under the certificatio n mark scheme operated by 
the Uganda National Bureau of Standards and in conjunction 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 s tandard under a system of supervision, control and testing in accordance with the 
certification mark s cheme of the Uganda National Bureau of Standards. UNBS marked products are 
continually checked by UNBS for conformity to that standard.  
Further particula rs of the terms and conditions of licensing may be obtained from the Director, Uganda 
National Bureau of Standards.  
 
 DUS 191: 2020    
 
ICS 71.100.70 
Price based on nn pages  
© UNBS 2020 – All rights reserved