Due to recent reports of several incidents where Diesel Exhaust Fluid (DEF) was mistaken for Fuel System Icing Inhibitor (FSII) and pre-mixed with Jet Fuel, it resulted in potentially catastrophic events. See the report here : Aircraft DEF Contamination Working Group Report-FINAL
If your operation works with FSII, Emcee has developed a quick test kit that can determine if FSII is free of DEF prior to the addition of FSII to aviation fuel. See the Test Procedure here : DEF in FSII Test rev 1
Feel free to contact us if you are interested to find out more.
Emcee DEF Contamination in FSII Test Kits