Growing up in Seoul and then living in New York, I noticed how differently the two city’s public transit systems use light. Seoul’s stations are bright and clean but often feel harsh and overexposed, while New York’s are older and moodier, yet sometimes feel warmer and more comfortable. So when I found out that NYC was undergoing a major LED replacement, I started questioning whether this shift toward higher brightness would genuinely improve the rider experience.

The MTA’s recent Re-NEW-vation program replaces older fluorescent fixtures with brighter LEDs under the belief that more light creates safer stations. I wanted to test that logic. I conducted field studies at four NYC stations, measuring both horizontal and vertical illuminance and pairing those measurements with on-site rider surveys about perceived brightness and safety. What I found was that higher illuminance did not consistently translate to a stronger sense of safety.

To understand what shapes safety perception, I created eight digitally rendered lighting scenarios in AGI32. Each one tested different luminance distributions, especially the relationship between floor and wall brightness. Participants evaluated these scenarios across brightness, visual comfort, spatial clarity, safety, and overall preference.

In both studies, luminance balance (how bright surfaces appear to the eye relative to one another) mattered far more than raw light levels. A moderate 2:1 wall-to-floor luminance ratio consistently supported higher feelings of safety and comfort, even when the overall output was lower. I believe that in public transit, brighter isn’t always better—but better lighting can make people feel safer.