The telecommunications industry is becoming increasingly conscious of energy consumption and the environmental footprint of its data centers. One energy-efficient approach, free air cooling, uses ambient air instead of air conditioning to cool data-center equipment. Free air cooling is being adopted in existing data centers with equipment that has not been designed or qualified for a free air cooling regime. Traditionally, product qualification is based on passing tests based on industry standards. The industry standards are assumed to conform to some expected environmental conditions. However, environmental conditions under free air cooling may go beyond those expected conditions. This paper identifies the performance and reliability risks associated with the implementation of free air cooling. A prognostics-based approach to assess and mitigate the risks of telecom equipment under free air cooling conditions is developed for risk mitigation. A case study is presented to demonstrate the implementation process of this approach. (C) 2012 Elsevier Ltd. All rights reserved.