Natural ventilation, harnessed by New Kingdom Egyptian tomb builders, may explain the changed floor levels in the Valley of the Kings tomb KV5

This article offers a plausible explanation for the floor level changes made during the construction of tomb KV5 in the Valley of the Kings. The construction of ancient Egyptian single entrance subterranean corridor tombs would have required a natural ventilation system; otherwise workers would have suffocated from the diminished oxygen in the depths of the tunnels and from the dust that resulted from the construction. This article postulates that the ancient Egyptians understood the concept of air exchange where, when in the desert, the outside air temperature drops dramatically in the evening causing a cool air draught to flow into the excavations that flushed out the stale air and dust, and replaced it with fresh air, enabling the workers to continue working day after day.