quantification co2e emissions in tehran’s hospitals using the aga khan development network’s approach

Introduction: carbon dioxide (co₂), the most abundant greenhouse gas, has reached an atmospheric concentration of 411 ppm, its highest level in the past 650,000 years. to effectively reduce the carbon footprint, accurately measuring these emissions is a crucial first step. this study focuses on quantifying the carbon dioxide equivalent (co2e) emissions from six selected hospitals in tehran, providing essential data to inform targeted sustainability efforts in the healthcare sector.materials and methods: this cross-sectional study quantified greenhouse gas emissions from six major hospitals in tehran using the aga khan development network (akdn) carbon management tool, supplemented by emission factors from the uk department for environment, food and rural affairs (defra). data were collected from hospital records and relevant departments using standardized checklists designed according to akdn guidelines. the sources of emissions assessed included energy consumption, anesthetic gases, inhalation devices, waste management, transportation and supply chain activities. all collected data were converted to carbon dioxide equivalent (co₂e) using established emission factors.results: the total co2e emissions from the six hospitals amounted to 28,260.74 tons. energy consumption was the largest contributor, accounting for 57% (16,182.5 tons) of emissions, followed by anesthetic gases at 40% (11,313.67 tons). waste management (626.36 tons), transportation (89 tons), inhalation devices (26.75 tons), and supply chain activities (22.58 tons) contributed smaller shares.conclusion: the study highlights the urgent need for targeted strategies to reduce greenhouse gas emissions in healthcare settings. recommendations include shifting torenewable energy sources, substituting high global warming potential anesthetic gases with lower-impact alternatives, optimizing supply chain logistics, and improving waste management practices. implementing these measures can significantly reduce the carbon footprint of hospitals while maintaining quality care. this study provides a foundation for future emission reduction efforts in iran’s healthcare sector, aligning with global climate goals.