Coal seam methane reservoir assessment is one of the core businesses of Sigra. Sigra can conduct field and laboratory measurements to assess reservoir properties. Using this information it can predict reservoir behaviour so that the correct production techniques can be used. Sigra also monitors reservoir performance to ensure that maximum production is achieved.

Coal seam methane is variously described as "Coal bed methane" and "Coal seam gas".

The 1987 SPE Paper "Reservoir Engineering in Coal Seams: Part 1 - The Physical Process of Gas Storage and Movement in Coal Seams", written by Sigra's managing director, was a landmark in presenting an understanding of the unique characteristics of coal seams, especially permeability variations related to effective stress variations. These are brought about by the withdrawal of fluid and coal matrix shrinkage. With refinements this remains the basis for predicting reservoir permeability change.