Chemicals have limited effects in aerosol form.
If an atomized biocide does not hit a bacteria in the air, it cannot kill it. Spraying lots of biocides cause other contamination problems, leaving undesirable residues. Heat is one good way to kill germs, provided they are in boiling water. It's not the same using heat in air as it's impractical. It holds several granted patents in many countries and also patent pending in some others.