But even in his wildest fantasies, the teenage ruler could never have imagined that he would become the rock star of the pharaohs. Since British archaeologist Howard Carter discovered his tomb in 1922, countless thousands of tourists have come to visit, descending a flight of stairs and a sharply sloping corridor to arrive at the painted burial chamber.

And therein lies the problem. As breathtaking as a visit to the tomb may be, people eventually have to breathe. And with each breath, they exhale bacteria, mold, and moisture.

In one day 400 visitors can leave behind an ounce of vapor. Add body heat and the warmth from light bulbs, and the 1,182-square-foot (109.83-square-meter) space turns almost tropical.

That's an unhealthy environment