How is perception distance calculated?

Perception distance is typically calculated based on the time it takes for a person to recognize and react to a stimulus, often in relation to speed and visibility conditions. It involves assessing the driver's speed and the time required to identify a hazard, usually expressed in feet or meters. The formula often used is: Perception Distance = Speed (in feet per second) × Perception Time (in seconds). This helps determine how far a driver travels before they can respond to potential dangers on the road.