Piston effect platforms with a single tunnel, however, air quality worsens when relying on the piston effect alone for ventilation. This still allows for potential energy savings by taking advantage of the piston effect rather than mechanical ventilation where possible. Tunnel boom is a loud boom sometimes generated by high-speed trains when they exit tunnels. These shock waves can disturb nearby residents and damage trains and nearby structures. The perception of this sound by humans is similar to that of a sonic boom from supersonic aircraft, but unlike a sonic boom, tunnel boom is not caused by trains exceeding the speed of
Shock tube detonator One manufacturer estimates that over 2 billion feet of shock tube are used each year worldwide, in commercial blasting, military demolition, theatrical special effects, automobile airbags, aircraft escape systems, IED initiation and professional fireworks. Shock tube detonator A shock tube detonator is a non-electric explosive fuze or initiator in the form of small-diameter hollow plastic tubing used to transport an initiating signal to an explosive charge by means of a percussive wave traveling the length of the tube. It was invented by Per Anders Persson of Nitro Nobel AB, patented, and sold by them under the registered trademark Nonel, containing