In October 2024, the European Union (EU) issued a Directive establishing a series of limit values, which, once transposed into national law by EU Member States, will become mandatory. This Directive is less restrictive than the WHO guideline values published in 2021. Using dose-response functions specifically calculated for every Spanish province, this study sought to ascertain how many short-term, all-cause hospital emergency admissions (ICD-9: 1-799 and ICD-10: A00-R99) were attributable to NO