In the last time, some factors and especially the environmental protection requirements have forced to add the ecological criterion for design of electric equipments, within a new Eco-design concept. The essence of this concept consists in the integration of environmental aspects at project phase, taking into account full life cycle of product. The work presents some theoretical and practical aspects of eco-design for electric equipments. The actual eco-design conception combines Qualitative Assessment of Life Cycle Criteria with a quantitative method based on the Product Carbon Footprint. The calculation of the last indicator means the quantification of the greenhouse gases emissions (kgCO2 equivalent) during the life cycle of products and services. From the study of the technical literature and its own practical work, the author has found that "maintenance", one of the phases of the life cycle of electric equipment, is not sufficiently analyzed and quantified in terms of negative impacts on the environment, including CO2 emissions involved in the service performed. As a result, it has achieved himself and in collaboration with other specialists studies and research, with the ultimate objective of establishing environmental performance indicators in this field. Thus, the main objective of this paper refers to the original contribution of the author who has established two such indicators, namely: 1. Absolute indicator "CO2 emissions involved in service (Es) [kg CO2]" and 2. Relative indicator "Specific CO2 emissions involved in service (es) (kg CO2 / euro)"