Subway tunnels are filled with a lot of dust, including metal dust generated by track friction, particles left over from construction, and dust brought in from the outside.
Subway tunnels are filled with a lot of dust, including metal dust generated by track friction, particles left over from construction, and dust brought in from the outside.
In the building fire safety system, the smoke exhaust valve is an important part of the smoke exhaust system, and its performance is directly related to the efficiency of personnel evacuation and fire extinguishing in emergency situations such as fire.