高铁车厢二氧化碳超标？专家澄清

Core Viewpoint - The indoor carbon dioxide concentration standard for passenger trains in China is set at 2500ppm, which is considered safe for passenger health. Recent claims of CO2 levels exceeding 1000ppm in high-speed trains have been addressed by experts, clarifying that the standards for rail vehicles differ from those for civil buildings [1][2]. Group 1 - The standard for indoor CO2 concentration in passenger trains is based on the TB/T 3493-2017 standard, which allows levels up to 2500ppm, while European standards permit up to 5000ppm [1]. - The reported CO2 levels were compared to the GB 50736-2012 standard for civil buildings, which is not applicable to passenger trains. The standards for train CO2 levels are established based on the unique characteristics of mobile transport equipment [1][2]. Group 2 - The train's air-tight design ensures that air exchange is managed entirely by the air conditioning system, providing a fresh air volume of over 15m³/h and achieving air exchange rates of 6 to 12 times per hour [2]. - During normal operation outside of tunnels, CO2 levels typically remain below 1500ppm. However, when passing through tunnels, the pressure protection system may temporarily increase CO2 levels due to the closure of external air exchange, but this is not harmful to passengers [2].