Tehran University of Medical Sciences International Journal of Occupational Hygiene 2008-5109 9 2 2017 06 24 66 77 EN NAZAK SHAHBOD Department of Environmental Management, Graduate School of the Environment and Energy, Science and Research Branch, Islamic Azad University, Tehran, Iran. NABIOLLAH MANSOURI Graduate School of Environment and Energy, Science and Research Branch, Islamic Azad University, Tehran, Iran. MANSOUR BAYAT Dept. of Microbiology, Faculty of Veterinary Specialized Sciences, Science and Research Branch, Islamic Azad University, Tehran, Iran. JAFAR NOURI Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran. JAMAL GHODDOUSI Graduate School of Environment and Energy, Science and Research Branch, Islamic Azad University, Tehran, Iran. 2017 03 13 2017 06 20 Being threatened by various facilities in a city, modern urban environments have become extremely vulnerable and fragile. Hospitals are among potentially high-risk facilities. Environmental awareness is relatively lacking in the health sector with few organizations measuring their performance. Therefore, the issue is exceedingly important. This study aimed to identify and prioritize factors that influence environmental performance in hospitals. To identify factors that influence environmental performance in hospitals, a comprehensive review of literature was performed to compile a list of criteria, sub-criteria, and indicators of environmental performance in healthcare centers. The list was then adjusted by experts in the field using the fuzzy Delphi method and the factors were prioritized using fuzzy analytical hierarchy process. In order to verify the results, a fuzzy technique was also applied to determine the order of preference by similarity to ideal solution. Therefore to verify the weights and priorities assigned to the factors influencing environmental performance, the factors were once again rated by experts based on the criteria of specificity, measurability, availability, being realistic, and time-related. Six criteria, 22 sub-criteria, and 48 indicators were identified and prioritized. Furthermore, Fuzzy AHP and Fuzzy TOPSIS resulted in the same prioritization of the factors. Therefore, the results obtained from Fuzzy AHP are acceptable. Using appropriate indicators together with appropriate techniques can serve to improve the environmental performance in health care centers. The obtained results showed that the FAHP method could be used for prioritizing environmental performance factors in hospitals successfully. https://ijoh.tums.ac.ir/index.php/ijoh/article/view/258 https://ijoh.tums.ac.ir/index.php/ijoh/article/download/258/354