Part 11/15:
Upon their initial plunge into the cave, both explorers took the proper precautions, covering their air consumption. However, when sinus issues came up and Roger had to withdraw, he expected Martin to follow suit. Martin presumed he could venture deeper on his own to explore the new terrain, which was unwise considering their limited air supplies.
As Martin journeyed deeper, risk outweighed caution. The exploration exceeded his air reserve's calculations—a critical error against the “rule of thirds,” a cardinal principle in cave diving. Separated from Roger and with air running low, Martin had to make tough decisions amid rising panic.