when was the first handheld blow dryer invented
Hair dryer Around 1915, hair dryers began to go on the market in handheld form. This was due to innovations by National Stamping and Electricworks under the white cross brand,[11] and later U.S. Racine Universal Motor Company and the Hamilton Beach Co., which allowed the dryer to be small enough to be held by hand. Even in the 1920s, the new dryers were often heavy, weighing in at approximately 2 pounds (0.9 kg), and were difficult to use. They also had many instances of overheating and electrocution. Hair dryers were only capable of using 100 watts, which increased the amount of time needed to dry hair (the average dryer today can use up to 2000 watts of heat).[12]
Gas duster True "air dusters" using ordinary air are also available in the market. These typically have much shorter run times than a chemical duster, but are readily refillable. Both hand pump and electric compressor models have been marketed. The maximum pressure for an aerosol can is typically 10 bar (145 psi) at 20 C (68 F).[6] Therefore, a fully compressed air duster will exhaust air about 10 times the can volume. Recently electronic versions which only use air have become viable alternatives that are preferred by many large corporations due to the fact that they contain no hazardous chemicals, are safe for the environment, do not freeze and they cannot be abused by addicts looking to get high. The leading plug-in alternatives are made by DataVac and Airrow and the leading cordless alternative is made by Canless Air System.