This paper addresses ontologies of intentional and unintentional processes. Specifically, a methodology for developing processes ontologies is described. Typically, domain ontologies are developed in an ad-hoc fashion, without the reasons and justifications of the class structure. To resolve this issue, we propose a methodology based on Formal Concept Analysis (FCA) as a way to assist the development of a domain ontology. FCA is an analysis technique for knowledge processing based on applied lattice and order theory. The methodology is illustrated with the development of an explosion ontology.