Vanguard Smokesonic: in the Line of Fire

In the first half of the 20th century, most automatic fire alarms were heat-activated. Starting in the 1950s, however, more sensitive smoke detectors were introduced, working on one of two detection principles: photoelectric and ionization. In this video, we look at three different smoke detectors and discuss how this life-saving technology evolved over time.

Wilkinson Alarm Video:    • SHORT: Wilkinson Fire Alarm  
Merlite Alarm Video:    • SHORT: Merlite Fire Alarm  
Guardsman and Vanguard Alarm Video:    • Guardsman and Vanguard Alarms: A Technolog...  

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