专家澄清：我国旅客列车室内二氧化碳浓度没超标

Core Viewpoint - The indoor carbon dioxide concentration in China's passenger trains does not exceed safety standards, and there is no need for excessive panic regarding the reported levels [1] Group 1: Standards and Regulations - The standard limit for indoor carbon dioxide concentration in China's passenger trains is set at a maximum of 2500 ppm according to TB/T 3493-2017 [1] - In comparison, the European standard EN13129-2016 allows for a maximum of 5000 ppm in passenger trains [1] - The reported measurements that exceeded 1000 ppm were based on the GB 50736-2012 standard for civil buildings, which is not applicable to passenger trains [1] Group 2: Air Quality Management - The design of the train's air conditioning system ensures that the average fresh air supply exceeds 15 m³/h per person, with air exchange rates between 6 to 12 times per hour [1] - During normal operation outside of tunnels, the carbon dioxide concentration typically does not exceed 1500 ppm [1] - When passing through continuous tunnel sections, the train's pressure protection system temporarily closes the air exchange with the outside, which may cause a short-term increase in carbon dioxide levels, but this does not pose a health risk to passengers [1]