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History Channel - Bunker: World's Largest and Most Secret - History Documentary Films 2016

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Bunker: World's Largest and Most Secret - History Documentary Films
Bunkers are primarily underground, compared to blockhouses which are mostly above ground. Bunkers can additionally be used as security from twisters.

Common commercial bunkers include extracting websites, food storage space locations, disposes for materials, data storage space, and in some cases living quarters. Bunkers disperse the blast wave from close-by explosions to avoid ear and inner injuries to individuals sheltering in the bunker. Nuclear bunkers should also cope with the underpressure that lasts for many seconds after the shock wave passes, and block radiations.

A bunker's door should be at the very least as strong as the walls. In bunkers inhabited for extended periods, huge amounts of ventilation or cooling must be supplied. Bunkers can be destroyed with powerful explosives and bunker-busting warheads.

History Channel - Bunker: World's Largest and Most Secret - History Documentary Films 2016