Neon Signs Can Last Over 50 Years

The iconic hum and vibrant glow of a neon sign are hallmarks of classic cityscapes, and their remarkable longevity is a testament to elegant science. Unlike an incandescent bulb that relies on a fragile filament to burn hot, a neon tube has no moving parts or components that easily wear out. A high-voltage transformer energizes electrodes at either end of the tube, exciting the atoms of the noble gas sealed within. This causes the gas to enter a plasma state, which emits a steady, colorful light without degrading the atoms themselves.

First demonstrated by French engineer Georges Claude at the 1910 Paris Motor Show, the technology quickly became a staple of modern advertising. Interestingly, only the brilliant red-orange color comes from pure neon gas. To create other hues, sign makers use different noble gases, such as argon for a soft blue, or coat the inside of the tubes with fluorescent phosphors that glow in various colors when excited by mercury vapor.

While the neon gas itself is stable, the sign's lifespan is ultimately limited by its other components. The high-voltage transformer that powers the sign may eventually fail, and the electrodes can slowly degrade over many decades. Even so, the fundamental principle of exciting a sealed, inert gas is so robust that with proper maintenance, these luminous works of art can easily shine for half a century or more, becoming enduring landmarks.