Exploring practical methods for preparing for the end times, including analysis of end time scripture and prophecy, current events, prepping and self-defense.
Interesting diagram. If this complex is on flat ground, forced ventilation is almost a requirement - definitely a requirement if any kind of fire is used for cooking. If on a hillside, natural ventilation (air movement via intake at lower elevation openings, and exhaust at higher elevation openings) will provide necessary ventilation. Ventilation of underground workings/complexes is not a trivial problem - at least if those inhabiting the workings/complexes are going to be breathing safe air.
Good point. There must have been techniques developed for 19th century mining/construction that would be simple to implement.
Nineteenth century mine ventilation techniques still relied on mechanical fans of some sort, although they were crude by current standards.Pre-industrial revolution mine ventilation at best consisted of multiple vertical shafts (or a single shaft split in two, with one side being for fresh air and the other for exhaust) with some mechanism, such as a fire, to force the flow of air via convection. There is also research suggesting ancient miners may have used wind deflectors to deflect the air of prevailing winds down shafts - again multiple shafts were required.
... from Jon Low . There is a lot of good stuff in this post, and Jon seems (at least to me) to have included much more of his own comment...