Natural gas is obtained from a wide range of sources and may differ not only in composition and processing, but also in energy content.

The main component is methane (CH4); it usually constitutes between 75-99%, but deviations are not unusual. Natural gas contains small amounts of ethane, propane, butane and ethylene.

Natural gas is commonly supplied via pipeline or a gas infrastructure, but thanks to recent developments it can be liquefied easily and economically. Consequently, it can be transported as LNG (Liquefied Natural Gas) by vessels all over the world.

There are different types of natural gas depending on the composition. H-gas (high calorific gas) is gas with a high content of energy and methane. L-gas (low calorific gas) has a lower content of energy and methane but higher amounts of nitrogen and carbon dioxide. Of course, these types of natural gas have different characteristics in terms of combustion ( see the gas fuel specification below).

For use of natural gas in our engines, the gas must comply  with the general applicable specifications for natural gas, the specific MAN ES  requirements, be clean, dry and cooled (free of water, hydrocarbon condensate and oil) when fed to the engine.

If you are in doubt about your gas quality, do not hesitate to contact us. Our well equipped laboratory can check your fuel and inform about the best suited MAN engine.

The MAN engines, desiged to burn natural gas are our spark ignited gas engines, which run highly efficient on pure gas.

Our dual fuel engines can run on both liquid fuel as well as on natural gas in graduating fuel proportions.

Gas fuel specifications

Natural gas

Unit 35/44DF


Calorific value (LHV)




Methane number  -



Hydrogen sulphide content (H2S)




Total sulphur content
mg/Nm³ 30

Particle concentration

Max. mg/Nm³ 50
Particle size
Total fluoride content
Total chlorine content

Nm³ corresponds to one cubic meter of gas at 0 °C and 101.32 kPa.

All data provided on this site is for information purposes only, explicitly non-binding and subject to changes without further notice.