The physical properties are investigated in fuel analytics.

The area of fuel analytics is divided as followed in our lab:

  • Diesel
  • Gasoline (petrol)
  • Fuel oil
  • Plant oil
  • Biodiesel
  • ....

We perform the following analytical methods for fuel analysis in our lab:

Analytical methods:


ISO 3675

The density of oil or fuels like diesel can be measured according to this method. The sample has to be liquid at 15°C and the vapor pressure has to be lower than 100kPa.

Flash point


Petroleum products with a flash point between 79°C and 400°C can be measured with a Cleveland flash point device. For the procedure a defined amount of sample is heated up continuously. In the predicted region of the flash point every 2°C a flame is placed over the sample. The test is accomplished when the sample ignites.


This technique is used to measure the transmission of infrared light through a sample. In general different molecule structures absorb different infrared wavelength. The resulting spectrum consists of a specific pattern for the sample. In general the IR-spectroscopy is used for “finger print” analysis e.g. to control the purity of oil batches.


ASTM D445; DIN EN ISO 3104; DIN 51562-1

The viscosity plays an importantrole in motor and hydraulic oils. It is from interest that e.g. hydraulic oils don’t change their viscosity after dynamic stress, because this can cause damages to the tubes or engines. In our lab we measure by default the dynamic and kinetic viscosity.

Dynamic viscosity: Describes the flow resistance of a fluid.
Kinetic viscosity: Describes the ratio between dynamic viscosity and the density of a fluid.

Water content according to Karl Fischer

ASTM D6304; DIN 517

The amount of water in a sample is determined by titration with an iodine-containing solution. There are two ways to measure the water content:

Direct method (DIN 51777-1)
All liquids like alcohols and oils which are soluble in the titration solvent can be injected directly into the titration cell.

Indirect method (DIN 51777-2)
All liquids which are insoluble in the titration solvent and have a boiling temperature higher than 200°C are placed in a heating device and heated up to 200°C. The evaporated water is transported into the measuring chamber with a dry airflow. Afterwards the measurement is the same as for the direct method.