Today, the Heating Ventilation & Air Conditioning (HVAC) class let us join them to practice building electrical circuit boards. We spent the day connecting duplex sockets to single pole switches and lamp boxes, being careful not to electrocute ourselves and cheering when the light bulbs worked. It was enlightening, if not a little terrifying.

According to the Bureau of Labor Statistics, in 2015, construction laborers earned a median hourly wage of $17.57, while electricians earned $26.73. After today, I can see why.

Electricity is not to be trifled with. The instructors kept pointing out, “It’s live; it could kill you.” Literally, they pointed, extending a single pinky or index finger, so if—God forbid—they did brush up against a live ungrounded wire, the shock wouldn’t cause two fingers to reflexively grip the live wire, resulting in more serious burns. I tried to play it cool, but when an industrial air vent unexpectedly kicked on in the background with a boom! I jumped out of my skin.

After about six hours of lacing up Rube Goldberg networks of black wires and gold screws, white wires and silver screws, and copper wires and green screws, our instructor invited the HVAC students to join us in our drywall project across the hall. He suggested it might be convenient and efficient if electrical and HVAC technicians could do their own finish work, rather than having to call in a sheetrock team.

One HVAC guy—no doubt, familiar with the BLS earnings matrix—laughed, then said cheerfully, “That’d be an expensive way to repair drywall.”