LOI

This method is used to determine the burning behaviour of plastics with the help of the limiting oxygen index (LOI).

It calculates the minimum oxygen concentration that will just about support combustion of the test specimen in a mixture of oxygen and nitrogen. The results are referred to as the limiting oxygen index (LOI).

Summary of the test method:
A test specimen is placed vertically in a mixture of oxygen and nitrogen flowing upwards through a transparent chimney and ignited with a propane gas flame. The burning behaviour of the specimen is observed and the burning time of the burned distance calculated.