Limiting Oxygen Concentration (LOC) Test
Limiting Oxygen Concentration (LOC) Test:
The Limiting Oxygen Concentration (LOC) is the oxygen concentration below which combustion is impossible, regardless of fuel concentration. The LOC is determined by the inert (non-flammable) gas utilized. Dust samples of varied sizes are scattered in a 20 liter spherical tank, and an intense ignition source is used to try to ignite the ensuing dust cloud. Tests for decreasing oxygen concentrations (replaced with inert gas) are performed until the LOC is determined. The data obtained offers a relative estimate of dust cloud’s deflagration characteristics. A dust cloud environment with oxygen concentrations below the LOC cannot support deflagration.
The Limiting Oxygen Concentration (LOC) test is carried out in accordance with the current edition of the ASTM E2931 standard.
Common Uses of Combustible Dust Testing
- To determine the combustibility and explosibility of a material.
- Quantifying dusts by measuring their ignition and explosion characteristics.
Advantages of Combustible Dust Testing
- The American Society for Testing and Materials has standards in place to carry out these tests.
- Proper testing can prevent operational hazards in factories.
Industrial Applications of Combustible Dust Testing
- Refineries
- Chemical factories
- Metal processing factories
- Woodworking
- Coal-fired power generation
