PURPOSE: The purpose of this paper is to provide a detailed accounting of energy and materials consumed during magnetic resonance imaging (MRI). DESIGN/METHODOLOGY/APPROACH: The first and second stages of ISO standard (ISO 14040:2006 and ISO 14044:2006) were followed to develop life cycle inventory (LCI). The LCI data collection took the form of observations, time studies, real-time metered power consumption, review of imaging department scheduling records and review of technical manuals and literature. FINDINGS: The carbon footprint of the entire MRI service on a per-patient basis was measured at 22.4kg CO2eq. The in-hospital energy use (process energy) for performing MRI is 29kWh per patient for the MRI machine, ancillary devices and light fixtures, while the out-of-hospital energy consumption is approximately 260 percent greater than the process energy, measured at 75kWh per patient related to fuel for generation and transmission of electricity for the hospital, plus energy to manufacture disposable, consumable and reusable products. The actual MRI and standby energy that produces the MRI images is only about 38 percent of the total life cycle energy. RESEARCH LIMITATIONS/IMPLICATIONS: The focus on methods and proof-of-concept meant that only one facility and one type of imaging device technology were used to reach the conclusions. Based on the similar studies related to other imaging devices, the provided transparent data can be generalized to other healthcare facilities with few adjustments to utilization ratios, the share of the exam types, and the standby power of the facilities' imaging devices. PRACTICAL IMPLICATIONS: The transparent detailed life cycle approach allows the data from this study to be used by healthcare administrators to explore the hidden public health impact of the radiology department and to set goals for carbon footprint reductions of healthcare organizations by focusing on alternative imaging modalities. Moreover, the presented approach in quantifying healthcare services' environmental impact can be replicated to provide measurable data on departmental quality improvement initiatives and to be used in hospitals' quality management systems. ORIGINALITY/VALUE: No other research has been published on the life cycle assessment of MRI. The share of outside hospital indirect environmental impact of MRI services is a previously undocumented impact of the physician's order for an internal image.