Furnace oil is a dark viscous residual product used as a fuel in different types of combustion equipment. It conforms to IS:1593-1982 for fuel oils. Presently MV-2 grade (kinematic viscosity range of 125 to 180 CSt at 50°C) conforming to this specification is being marketed. Broadly its applications can be classified as:

Steam Raising

In the process industry and thermal power stations.

Industrial Furnaces

Metallurgical furnaces, pottery and brick kilns, glass furnaces etc.

Special Applications

In marine engines and slow speed engines for power generation.
For drying tea leaves
In gas turbines for power generation
As a feed stock for fertiliser manufacturing
In thermic fluid heaters and hot air generators


While FO is used in the DG sets there is no evaluating property like Cetane number or CII. Instead of that, calculated carbon aromaticity index or CCAI is calculated to find out the suitability. It is based on density and viscosity of the fuel. Normally a value between 800 to 860 means good fuel for DG sets while values more than 860 severe indicate unsuitability which may cause engine damage. Lower values than 800 may not be very good but are not as bad as those beyond 860.

Furnace Oil manufactured by MRPL comply with the requirements of IS 1593 – 1982 specifications laid by Bureau of Indian Standards.