Jet Fuel system Icing Inhibitors Determination via Refractive Index – ASTMD5006
Application Method

Jet Fuel System Icing Inhibitors (FSII) Determination

Application Method

Determine the concentration of fuel icing inhibitors in jet fuels using a digital refractometer

Jet fuel system icing inhibitor FSII
Jet fuel system icing inhibitor FSII

Jet fuel system icing inhibitor or FSII, what is it?

Fuel system icing inhibitor (FSII) is an additive, such as Diethylene Glycol Monomethyl Ether (DiEGME), used in aviation fuels with the main objective of preventing the ice formation in fuel lines. Aviation jet fuels can contain some dissolved or free water; this is the reason of the risk of ice formation at high altitudes.

The importance of jet fuel system icing inhibitor (FSII)

Aviation Jet fuels differs mostly in their flash point and freezing point. This last one is crucial, since water can be often present in jet fuel and the temperature cruising altitudes can reach -50 °C, is necessary to use fuel-system icing inhibitors (FSII) as a fuel additive to reduce the risk of ice formation and prevent blocking fuel lines and filters obstructing the flow of it and shutting down an engine.

With this application note, you will learn to determine the correct concentration of jet fuel icing inhibitor in any jet fuel containing FSII, according to ASTM D5006 using METTLER TOLEDO’S portables refractometers in site.

Download our fuel icing inhibitors determination application to learn how to easily measure its concentration with portable refractometers.
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