Organizations are struggling to survive in today's competitive market. They are mostly obliged to meet customers' expectations and demand for sustainable products from one side and comply with governmental rules and regulations regarding energy, resources, materials, etc. on the other side. Therefore, measuring their sustainability performance and trying to keep up with the competitors is essential for their future development. Consequently, organizations' perception of operational sustainability can reveal their strategies on how to be sustainable, endeavouring the three pillars of economic, environmental and social. The present work investigates the role of indicators' choice and their meaning for sustainability assessment of manufacturing organizations. To this point, an analysis is conducted on the sustainability assessment of 100 manufacturing organizations using GRI indicators for assessing their sustainability state. A Formal Concept Analysis was run to look over the indicators and their interpretations to reach a given degree of sustainability of the organization.