高铁车厢二氧化碳浓度超标？专家澄清

Core Viewpoint - The reported CO2 concentration levels in high-speed train carriages do not exceed the established safety standards for passenger trains in China, despite public concerns regarding air quality [4][5]. Group 1: Standards and Regulations - The CO2 concentration control standard for passenger trains in China is set by TB/T 3493-2017, with a limit of 2500 ppm under normal operating conditions [4]. - European standards (EN13129-2016) allow for a CO2 concentration limit of up to 5000 ppm for passenger trains [4]. - The public concern referenced a standard (GB 50736-2012) applicable to civil buildings, which is not relevant to the standards for passenger trains [4]. Group 2: Air Quality Management in Trains - High-speed trains are designed with a fully sealed car body, relying on an air conditioning ventilation system to manage air quality, providing over 15 m³/h of fresh air per person [5]. - The trains achieve an air exchange rate of 6 to 12 times per hour, ensuring that CO2 levels typically remain below 1500 ppm during normal operation [5]. - During passage through tunnels, the pressure protection system may temporarily increase CO2 levels due to the closure of external air exchange, but this is not expected to impact passenger health [5].