A CRH5G train undergoes checks at a maintenance base in Xi'an, Northwest China's Shaanxi province on Thursday. [Photo/chinanews.com]

The temperature inside the train will be maintained at 24 degree Celsius with high-power air conditioners, even if the temperature outside reaches 40 degree Celsius or minus 40 degree Celsius. When it rains or snows, the train will automatically spray sand on rail to increase the friction.

More than 2,000 sensors and observation points have been installed on the train to monitor major systems and components, even though they themselves have self-protection function, to ensure maximum safety.