Background: Measuring the carbon footprint (CF) makes it possible to estimate the contribution of clinical activity to global warming. Aim: To measure the emitter components of CO2 equivalents (CO2e) at the Hospital Base, Puerto Montt (HBPM). Material and methods: Descriptive study with data collected retrospectively between January and December 2016 from the HBPM database. The data analyzes direct and indirect emissions as well as other indirect emissions beyond the organizational limits. Results: Of the 9,660.3 tons of CO2e emitted by the HBPM in 2016, 46% were derived from consumption of electricity, 29% derived from the generation of residues, and 10% from clinical gas consumption, of which Sevoflurane was the greatest contributor. Conclusions: Clinical gases are a significant source of CO2e emissions. Sevoflurane alone is in fourth place in CO2e emissions at the HBPM. Estimating the CF produced by HBPM is the first step in the discussion of measures to reduce the environmental impact of our activity.