# Why Pilots Dim All Cabin Lights During Night Landings: The 90-Second Survival Rule
If you have ever flown on a red-eye flight late at night, you probably noticed that minutes before touchdown, the cabin crew dims or turns off all interior lights and raises window shades.
Most passengers assume this rule is simply designed to help people relax. However, the real motivation behind this protocol relates to one of aviation's most crucial safety standards known as the **"90-Second Rule."**
---
## The Secret Behind the Intentional Darkness
* **Night Vision Adaptation:** The human eye takes between 10 to 20 minutes to adjust completely to total darkness. If an emergency evacuation occurs at night, moving instantly from bright cabin lights to pitch-black darkness would cause temporary blindness, severely hindering evacuation speed.
* **Locating Emergency Signage:** Dimming interior lights ensures passenger eyes are already pre-adjusted to spot glowing floor escape path lighting and emergency exit signs instantly from the first second of an incident.
*
