Introduction
Staircases are high-risk areas for falls, especially in the dark. PIR sensors can trigger lighting when someone approaches, improving safety and saving energy.
Applications
Automatic Stair Lighting
Lights turn on when person approaches staircase, turn off after they pass. Can be zoned to light only the steps being used.
Fall Detection
Detect if someone falls on stairs and trigger alert.
Direction Detection
With multiple sensors, detect whether person is going up or down to control lighting accordingly.
Sensor Placement on Stairs
Top and Bottom of Stairs
Detect approach from either end.
Midway on Landing
For fall detection and tracking on long staircases.
Under Handrail
Discreet placement that doesn’t interfere with lighting.
Lighting Control Logic
// Direction detection logic
if (topSensor.triggered && !bottomSensor.triggered) {
// Person at top - light staircase from top down
lightStaircase(TOP_TO_BOTTOM);
} else if (bottomSensor.triggered && !topSensor.triggered) {
// Person at bottom - light staircase from bottom up
lightStaircase(BOTTOM_TO_TOP);
}
Fall Detection Algorithms
Key indicators of a fall on stairs:
- Rapid downward motion (faster than normal walking)
- Prolonged inactivity after motion
- Detection at unusual height (sensor placed low)
- Multiple sensors triggered in quick succession
Safety Benefits
Well-lit stairs reduce fall risk. Studies show that properly illuminated staircases have 60% fewer accidents.
Energy Savings
LED lighting controlled by PIR sensors can reduce stair lighting energy consumption by 80-90% compared to always-on lighting.
Case Study: Apartment Building
An apartment building installed PIR-controlled LED strip lighting on staircases. Energy consumption for stair lighting dropped by 90% compared to always-on lighting, and resident satisfaction increased due to responsive lighting.
Conclusion
PIR sensors make staircases safer and more energy-efficient. They are a low-cost upgrade for any building, from single-family homes to high-rise apartments.