高铁车厢二氧化碳超标？专家澄清

Core Viewpoint - The article addresses concerns regarding the carbon dioxide (CO2) concentration levels in high-speed train carriages, clarifying that the reported levels exceed standard limits due to a misunderstanding of applicable regulations [3]. Group 1: Standards and Regulations - The CO2 concentration control standard for passenger trains in China is governed by TB/T 3493-2017, which sets the limit at 2500 ppm under normal operating conditions [3]. - In comparison, European standards (EN13129-2016) allow for a CO2 concentration limit of up to 5000 ppm for passenger trains [3]. - The reported passenger measurements referenced the GB 50736-2012 standard for civil buildings, which is not applicable to passenger trains [3]. Group 2: Train Design and Air Quality Management - High-speed trains are designed with fully sealed car bodies, and air exchange is managed entirely by the air conditioning ventilation system, providing a fresh air volume of over 15 m³/h per person [4]. - The trains achieve an air exchange rate of 6 to 12 times per hour, and are equipped with a pressure protection system [4]. - During normal operation outside of tunnels, CO2 levels typically do not exceed 1500 ppm; however, in tunnels, the system temporarily closes external air passages to prevent pressure fluctuations, which may cause a short-term increase in CO2 levels without impacting passenger health [4].