Smoke detectors - History of Smoke detectors
Stop, drop, and roll are common instructions given to those who catch on fire. However, these instructions are only useful if people are aware of a fire's existence. Fire detectors, created over 100 years ago, are responsible for warning people about a nearby fire and they successfully save hundreds of lives each year.
In 1890, Francis Robbins Upton provided the design for the first fire alarm. Surprisingly however, he never shared or created his design. Therefore, the first active heat detector was invented in 1902 by George Andrew Darby of England. It worked by detecting a fire through the sensing of high heat. However, the design was quite large and only feasible for use in factories or other industrial buildings.
Walter Jaeger, a Swiss physicist, created the first smoke detector in the 1930s. In his attempts to generate a poison gas detector he became frustrated by the failure of his design. To calm his nerves, he lit a cigarette, which surprisingly set off the alarm! His attempt to create a poison gas detector eventually failed, but the nation was rewarded by his accidental discovery and creation of a smoke detector. Unfortunately, like the heat detector, the smoke detectors of this time were huge and not available for household fire detection.
Although the large fire detection devices were available for purchase by 1951 in the United States, a household fire detector wasn't created until 1955. This first model was a heat detector, but a decade later the first smoke detector was introduced. The "SmokeGuard 700" was created by Duane D. Pearsall, and was much more effective than a heat detector at identifying fires quickly. Both models, however, were quite expensive and were not available to the majority of the working class population. By 1970 the price had decreased to $125 per unit, and continued its downward price spiral over the next two decades as the size continued to get smaller, and the ease of use increased.
Today, it is believed that photoelectric smoke detectors are the best fire alert option available. Working through the use of a light, which is shot inside of an open tunnel through which air flows, this device detects smoke by measuring a decrease in light intensity. Depending on the size of the fire and the device's placement, these smoke detectors can identify a fire 40-60 minutes after it begins. This quick alert time allows for the escape from the room or building, quelling of the fire, and if necessary stopping, dropping and rolling to eliminate its presence.