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A Hand Sanitizer dispensing machine is automatic, alcohol based hand sanitizer dispenser and non contact which is used in offices, hospitals, schools, work places etc. Basically, alcohol is a solvent and very good disinfectant as compared to liquid or solid soap. It is volatile and vaporizes fatly so it does not need water to wash out. It is proved that a concentration of > 70 % alcohol which can kills corona or other viruses in hands ultrasonic sensor which senses hand when placed near it, microcontroller used in that is the Arduino uno and which senses the distance and the result is the sanitizer.
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Zore et al. (2021) studied this question.
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