G/TBT/N/UGA/1651  
1 July 2022  
(22-5122) Page: 1/2 
Committee on Technical Barriers to Trade  Original:  English  
 
  
NOTIFICATION  
The following notification is being circulated in accordance with Article 10.6  
 
1. Notifying Member:  UGANDA  
If applicable, name of local government involved (Article 3.2 and 7.2):   
2. Agency responsible:   
Uganda National Bureau of Standards  
Plot 2 -12 ByPass Link, Bweyogerere Industrial and Business Park  
P.O. Box 6329  
Kampala, Uganda  
Tel: +(256) 4 1733 3250/1/2  
Fax: +(256) 4 1428 6123  
E-mail: info@unbs.go.ug  
Website: https://www.unbs.go.ug  
Name and address (including telephone and fax numbers , email and website 
addresses, if available) of agency or authority designated to handle comments 
regarding the notification shall be indicated if different from above:   
3. Notified under Article 2.9.2 [  ], 2.10.1 [  ], 5.6.2 [X], 5.7.1 [  ], 3.2 [  ], 7.2 [  ], 
other :  
4. Products covered (HS or CCCN where applicable, otherwise national tariff 
heading. ICS numbers may be provided in addition, where applicable):  Petroleum 
gases and other gaseous hydrocarbons. (HS code(s): 2711); Fuels (ICS code(s): 75.160)  
5. Title, number of pages and language(s) of the notified document:  DUS 
2522:2022, Standard Practice for Determining the Calculated Methane Number 
(MN C) of Gaseous Fuels Used in Internal Combustion Engines, First Edition ; (19 
page(s), in English)  
6. Descrip tion of content:  This Draft Uganda standards covers the method to determine 
the calculated methane number (MN C) of a gaseous fuel used in internal combustion 
engines. The basis for the method is a dynamic link library (DLL) suitable for running on 
computers with Microsoft Windows operating systems.  
This practice pertains to commercially available natural gas products that have been 
processed and are suitable for use in internal combustion engines. These fuels can be 
from traditional geological or renewable sources and include pipeline gas, compressed 
natural gas (CNG), liquefied natural gas (LNG), liquefied petroleum gas (LPG), and 
renewable natural gas (RNG) as defined in Section.  
The calculation method within this practice is based on the MWM Method as defined in EN 
16726, Annex A.2 The calculation method is an optimization algorithm that uses varying 
sequences of ternary and binary gas component tables generated from the composition 
of a gaseous fuel sample.3 Both the source code an d a Microsoft Excel -based calculator 
are available for this method.  G/TBT/N/UGA/1651  
 
- 2 - 
 
  1This calculation method applies to gaseous fuels comprising of hydrocarbons from 
methane to hexane and greater (C6+); carbon monoxide; hydrogen; hydrogen sulfide; 
nitrogen; and carbon dio xide. The calculation method addresses pentanes (C5) and higher 
hydrocarbons and limits the individual volume fraction of C5 and C6+ to 3  % each and a 
combined total of 5  %. (See EN 16726, Annex A.) The calculation method is performed 
on a dry, oxygen -free basis.  
7. Objective and rationale, including the nature of urgent problems where 
applicable:  Prevention of deceptive practices and consumer protection; Quality 
requirements  
8. Relevant documents:   
1. ASTM E29  
2. EN 16726 Gas infrastructure —Quality of gas —Group H, Annex A —Calculation of 
methane number of gaseous fuels for engines  
3. ISO 14912 Gas analysis —Conversion of gas mixture composition data  
4. ASTM_D8221_mzdll_ver2.32.0.dll  
5. ASTM_D8221_MNc_Method_ver1.32.1.xlsb  
6. ASTM_D8221_mzdll _ver2.64.0.dll  
7. ASTM_D8221_MNc_Method_ver1.64.1.xlsb  
9. Proposed date of adoption:  To be determined  
Proposed date of entry into force:  Not applicable.  
10. Final date for comments:  60 days from notification  
11. Texts available from:  National enquiry point [X] or address, telephone and fax 
numbers and email and website addresses, if available , of other body:   
Uganda National Bureau of Standards  
Plot 2 -12 ByPass Link, Bweyogerere Industrial and Business Park  
P.O. Box 6329  
Kampala, Uganda  
Tel: +( 256) 4 1733 3250/1/2  
Fax: +(256) 4 1428 6123  
E-mail: info@unbs.go.ug  
Website: https://www.unbs.go.ug