Every call we make, every text we fire off, every MMS we share is facilitated by cell towers. We’d be lost without them. So who makes sure they go up and stay up? Is there, like, a machine or something? No.

Despite the rapidly advancing technology they support, towers’ backup systems are still very basic. Human in fact. Just ask the small group of technicians responsible for climbing these mammoth transmitters’ knee-weakening heights on a daily basis. Theirs is a glamorless job made exciting only by its extreme danger.

Because of the tower climbing industry’s small size (comprised of only about 10,000 workers), raw numbers for on-the-job deaths are less than in more populated industries like fishing or mining. Still, WirelessEstimator.com, a site dedicated to providing comprehensive information about wireless communications construction and maintenance industries, reported 2006 fatalities at 183.6 per 100,000 workers—higher than any other industry on their list, including fisherman, loggers, and airline pilots.

Without more recent numbers and US Department of Labor corroboration, it’s hard to say for certain whether tower climbing is undisputedly the most dangerous job but, after taking a look at this video we found, it certainly seems like it could be the most harrowing. Look how high up that is!