# Oxidation Induction Time (OIT) or Temperature (OOT)

Oxidation Induction Time (OIT) or Temperature Determination by Differential Scanning Calorimeter (DSC)

This easy standard test procedure characterizes the oxidation stability of oils, fats, fuels or polymers. This information is important since external influences such as light, chemical or

biological media or radiation and temperature may alter the physical properties of the material and can lead to their failure.

The OIT Oxidation Induction Test is performed in a Differential Scanning Calorimeter (DSC). There are two standard OIT procedures: On the one hand there is the dynamic procedure, where the sample is continuously heated under presence of oxygen from the beginning. After melting, the oxidation can be observed as a change in the grade of the curve. The temperature and elapsed time at the beginning of oxidation is measured. And on the other hand there is the static procedure, where the sample is heated up in a protective atmosphere, typically nitrogen up to 190 – 220°C. After reaching the constant temperature, oxygen or air is introduced after a couple of minutes. The length of the time from introduction of the oxygen/air to the beginning of the oxidation (exothermic effect) is measured.