As it is not practical for keeping the windows open all the time in the hospital, UK researchers have introduced an air disinfector that pumps a continual stream of reactive hydrogen radicals into the atmosphere, killing microbes within minutes. Scientists were aware that microbes are killed by hydroxyl radicals, highly reactive agents constantly produced through natural reactions between airborne ozone and organic scented chemicals from plants such as pine trees so they recreated this effect using a customized device the size of a flower vase that constantly generates the radicals.

To get the effect, the device draws in oxygen and exposes it to electric currents to produce a cold plasma rich in ozone. The hydroxyl radicals are generated by constantly reacting the ozone with pre-loaded supplies of scented chemicals, called terpenes, in cartridges that need renewing each month. The ozone and terpenes are retained within the device and not released into the room.
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