Low Oxygen Index (LOI)

This method is used to determine the flammability of plastics with the help of the limiting oxygen index.

The test 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).

Pre-treatment:
> 88 h / 23 °C / 50 % relative humidity

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 flammability of the specimen is observed and the burning time or the burned distance calculated.

Limiting oxygen index (LOI) Limiting oxygen index (LOI)