Illuminating safety with Thomas Edison

When innovation met ingenuity: In 1921, the Johnson Controls Grinnell team turned to Thomas Edison for advice in perfecting a breakthrough sprinkler head. His insights helped shape a safer future, one that still echoes through Johnson Controls’ fire protection systems today.

An inventive spark that changed fire safety forever

In the early 1920s, as Thomas Edison’s electric light illuminated towns across America, the engineers at Johnson Controls Grinnell Automatic Sprinkler Company were working to protect them from the ever-present risk of fire.  Grinnell engineers had just developed the quartz bulb sprinkler head—a bold alternative to the standard solder-based design. It promised non-corrosive durability, faster heat sensitivity and stronger internal pressure resistance.

But it needed the right fluid to work. That’s when the team turned to Edison.

Visiting Edison’s lab on April 20, 1921, a Grinnell representative asked for advice on a suitable thermal-expansion fluid. Edison reviewed the prototype and recommended a class of chlorinated hydrocarbons, particularly triplicate chlorides, for their high expansion, low freezing point and non-combustibility.

This exchange came just a few years after Edison experienced the destructive power of fire firsthand. In 1914, a massive blaze destroyed much of his New Jersey laboratory. The loss was staggering — but Edison’s determination was greater. He rebuilt. And by 1922, Grinnell sprinkler systems had been installed in his new lab buildings—perhaps the most practical endorsement of their value.

From Edison’s lab to modern cities

That early partnership helped push fire protection into a new era—combining mechanical ingenuity with chemical precision. Today, Johnson Controls continues that legacy with advanced solutions in fire suppression and fire detection.

From Edison’s lab to today’s smart cities, Johnson Controls remains at the forefront of life safety innovation. Our 140-year journey has always been about more than engineering—it's about partnerships, curiosity, and a relentless pursuit of safer spaces.