KENYA STANDARD  DKS  91:202 1 
ICS 75.160.30  
Second Edition  
  
 © KEBS 2020   
 Petroleum and pe troleum products —
Liquefied Petroleum Gas (LPG) — 
Specification  
 
 
 
 DKS 91: 202 1 
ii © KEBS 2020  – All rights reserved  
 TECHNICAL COMMITTEE REPRESENTATION  
The following organizations were represented on the Technical Committee:  
ADS Africa  
BASF E.A.  
Beyond Borders  
Consumer Information Network  
CSI International L td. 
D.T. Dobie  
Diverse Management Consultancy L td. 
Geoscan Consultants  
Gulf Energy  
Heller Petroleum L td. 
IMCD Kenya  
Inspectorate E.A. L td. 
Intertek  
ISUZU E.A  
African Gas and Oil Company Ltd  
Rubis Energy (K) Ltd .  
Kenya Accreditation Services  
Kenya Petroleum Refineries Limited  
Kenya Power and Lighting Company  
Kurrent Technogies L td. 
Lacheka Lubricants L td. 
Lubrican ts 
National Environment Management Authority  
National Oil Corporation of Kenya  
OLA Energy  
Optimum  
Petroleum Institute of East Africa  
Sepyana Oil E.A  
SGS  
EPRA  
Simba Corp L td. 
Supply Cor  
Synergy Lubricants  
Total K L td. 
Vivo Energy  
Kenya Bureau of Standards — Secretariat  
REVISION OF KENYA STANDARDS  
In order to keep abreast of progress in industry, Kenya Standards shall be regularly reviewed.  Suggestions for 
improvements to published standards, addressed to the Managing Director, Kenya Bureau of Sta ndards, are 
welcome.  
© Kenya Bureau of Standards, 2020  
Copyright. Users are reminded that by virtue of Section 25 of the Copyright Act, Cap. 130 of 2001 of the Laws of Kenya, copyr ight subsists 
in all Kenya Standards and except as provided under Section 25  of this Act, no Kenya Standard produced by Kenya Bureau of Standards 
may be reproduced, stored in a retrieval system in any form or transmitted by any means without prior permission in writing f rom the 
Managing Director.   KENYA STANDARD  DKS 91: 202 1 
ICS 75.160.30  
Second Edition  
 
© KEBS 2020  – All rights reserved  iii 
  Petroleum and pe troleum products —Liquefied 
Petroleum Gas (LPG) — Specification  
Kenya Bureau of Standards, Popo Road, Off Mombasa Road,  
P.O. Box 54974 - 00200,  Nairobi, Kenya  
 +254 020 6948000, + 254 722202137, + 254 734600471  
 info@kebs.org  
 @KEBS_ke  
 kenya bureau of standards (kebs)  
  
DKS 91: 202 1 
iv © KEBS 2020  – All rights reserved  
 Foreword  
This Kenya Standard was prepared by the Petroleum and Petroleum Products Technical Committee under the 
guidance of the Standards Projects Committee, and it is in accordance with the procedures of the Kenya Bureau 
of Standards.  
This second edition cancels and replaces  the first edition KS 91:1985 which has been technically revised.  
During the preparation of this standard, reference was made to the following documents:  
xxxxx  
Acknowledgement is hereby made for the assistance derived from these sources.  
 KENYA STANDARD  DKS 91: 202 1 
 
© KEBS 2020  – All rights reserved  1 
 Petroleum and pe troleum products —Liquefied Petroleum Gas (LPG) — 
Specification  
1 Scope  
This Draft Kenya Standard specifies the requirements , sampling  and test methods for liquefied petroleum gas , 
LPG, ( commercial Butane) used as domestic, industrial and engine fuels.  
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, o nly the edition cited applies. For undated references, the 
latest edition of the referenced document (including any amendments) applies.  
ASTM D1657 , Standard Test Method for Density or Relative Density of Light Hydrocarbons by Pressure 
Hydrometer  
ASTM D 25 98, Standard Practice for Calculation of Certain Physical Properties of Liquefied Petroleum (LP) 
Gases from Compositional Analysis  
IP 235, Determination of density of light hydrocarbons – Pressure hydrometer method  
ISO 8973 , Liquefied petroleum gases — Calculation method for density and vapour pressure  
ASTM D1267 , Standard Test Method for Gauge Vapor Pressure of Liquefied Petroleum (LP) Gases (LP -Gas 
Method)  
ASTM D2598 , Standard Practice for Calculation of Certain Physical Properties of Liquefied Petroleum (LP) 
Gases from Compositional Analysis   
ASTM D1837, Standard Test Method for Volatility of Liquefied Petroleum (LP) Gases (Withdrawn 2017)  
ASTM D1838, Standard Test Method for Copper Strip Corrosion by Liquefied Petroleum (LP) Gases  
ISO 7941 , Com mercial propane and butane — Analysis by gas chromatography  
ASTM D2163 , Standard Test Method for Determination of Hydrocarbons in Liquefied Petroleum (LP) Gases 
and Propane/Propene Mixtures by Gas Chromatography   
ASTM D1945 , Standard Test Method for Analys is of Natural Gas by Gas Chromatography  
ASTM D1946 , Standard Practice for Analysis of Reformed Gas by Gas Chromatography  
ASTM D 2504 , Standard Test Method for Non -condensable Gases in C2 and  Lighter Hydrocarbon Products by 
Gas Chromatography  
ASTM D2158 , Standard Test Method for Residues in Liquefied Petroleum (LP) Gases  
IP 317 , Determination of residues in liquefied petroleum gases ― Low temperature evaporation method  
ISO 6326 -3, Natural gas — Determination of sulfur  compounds — Part 3: Determination of hydrogen sulfide, 
mercaptan sulfur and carbonyl sulfide sulfur by potentiometry  
ISO 4257, Liquefied petroleum gases — Method of sampling   
2 © KEBS: 2020  – All rights reserved  
 ASTM D 666 7, Standard Test Method for Determination of Total Volatile Sulphur  in Gaseous Hydrocarbons and 
Liquefied Petroleum Gases by Ultraviolet Fluorescence  
3 Terms and definitions  
3.1   
LPG (Liquified Petroleum Gas)  
petroleum gases that can be stored and/or handled in the liquid phase under moderate conditions of pressure 
and at ambient temperature . Which can be Pure butane or a mixture of propane and butane.  
3.2 
Commercia l Butane  
hydrocarbon product consisting mainly of butane gas for use where low volatility is required and complies with 
appropriate requirement as given in table 1.  
4 Requirements  
Liquefied petroleum gas es shall comply with the requirements given in Table 1 when te sted in accordance with 
the test methods prescribed therein.  
Table 1 — Requirements for Liquefied Petroleum Gas (LPG)  
Characteristic  Commercial 
Butane  Test method  
Density @20oC Kg/m3 
 Minimum 520  
Maximum 600  ASTM D1657  
ASTM D 2598  
IP 235  
ISO 8973  
Vapour pressure at 37.8º C kPa, max.   
528 ASTM D1267  
ASTM D2598  
Volatile residue 95 % evaporated, at 760 
mm Hg max   
2.2 ASTM D1837  
Or butane and heavier %, v/v, max.  - ASTM D2163  
IP 405  
ISO 7941  
Or pentane and heavier per cent v/v, max  
 2.0 ASTM D2163  
IP 405  
ISO 7941  
LPG Composition  Propane  20 %, max.  ASTM D2163  
IP 405  
ISO 7941  
 
Butane  80, %, min.  ASTM D2163  
IP 405  
ISO 7941  
 
Nitrogen  Nil  
ASTM D1945  
ASTM D1946  
ASTM D 2504  Oxygen  Nil DKS 91: 202 1 
© KEBS 2021 – All rights reserved  3 
 Residue on evaporation of 100 ml, max.  0.05 ASTM D2158  
IP 317  
Oil stain observation  Pass  ASTM D2158  
IP 317  
Corrosion, copper strip ( 1hr @37.8º C)  
max No.1  ASTM D1838  
Total sulphur mg/kg,  max.  140 ASTM D 6667  
ASTM D 5453  
ASTM D 7813  
EN 20846  
Moisture content  To be reported  ASTM 7995  
 
Free water content  None  Visual inspection  
Odour stenching mercaptan sulphur content 
as ethyl mercaptan, mg/ kg,  15-50 ASTM D 5305  
NOTE: The oduor 
should be 
detectable.  
Hydrogen sulphide (H 2S) mg/kg, max.  5 ISO 8819  
ASTM D4810  
ASTM D4084  
Hydrogen Sulphide  Negative  ISO 6326/3  
ASTMD 2420  DKS 91: 2020    
 
© KEBS 2021– All rights reserved   
 5 Sampling  
A representative sample of non -refrigerated commercial butane shall be taken  in accordance with the procedure 
given in ISO 4257.