Role: American Entrepreneur
Duane Darwin “Dewey” Pearsall (3 March 1922 – 11 April 2010) was an American entrepreneur best known for developing and marketing the first battery-powered home smoke detector in 1965.
Pearsall worked with Honeywell Corporation as a heating and air conditioning sales engineer for seven years before founding the Pearsall Company in 1955.Pearsall founded Statitrol Corporation in Lakewood, Colorado in 1963. A few months later Lyman Blackwell, one of Pearsall’s engineers at Statitrol, improvised a test to measure the flow of ions in an airstream discharging from a generator. When a technician, smoking nearby, casually exhaled smoke into the fan inlet of the generator, the ion meter pegged. Pearsall immediately realized that the basic ionization technology of this device could also be used for smoke detection. This accidental discovery was similar to a discovery made by Swiss physicist Walter Jaeger in the late 1930s. In 1965 Pearsall began the long process to develop and market a home smoke detector powered by a battery which could be easily installed and replaced. These first units were dubbed “SmokeGard 700,” Pearsall was awarded a design patent for this in 1973, and began mass-producing them in 1975. Shortly afterwards, he began working with the National Fire Protection Association (NFPA). His work with NFPA would eventually lead to the change of the uniform building codes to require smoke detectors in new construction. Statitrol sold the smoke detector invention to Emerson Electric in 1980.
