Ever since I learned that a school teacher in Louisiana was having good results using ozone shock treatments late at night (when nobody present) to destroy the harmful molds, viruses, and bacteria in her classroom, I’ve been searching the Internet to see if anyone else has had great results using ozone shock treatments in schools. I found a case where St Louis schools used ozone shock treatments using 2 control groups, schools with ozone and schools without! I was floored! (on page 348 of this NCBI gov archive) I quote:
Ozone in the St. Louis Schools.- After preliminary studies and tests made on a number of persons with ozone concentration many times that for ventilation, ozone machines have been installed in the air ducts of a number of the school buildings of St. Louis. The first machine was installed in the O’Fallon School in 1919. The effects on the comfort and health of teachers and pupils were so marked that in the summer of 1920 ozone machines were installed in thirteen old schools and put in the specifications of three new ones. In most instances, the principals and teachers were not apprised of the change in the ventilation, in order that psychology might not figure in the results. The most beneficial results were noticeable in a few weeks. Hundreds of visitors have visited the schools where this ventilation has been installed. To those who are not fully convinced of the merits of ozone in ventilation, an invitation is extended to visit the schools of St. Louis and make such tests as may seem desirable where the facilities for such are so large.- Jour. Am. Soc. of Heat.-Vent. Engineers, January 1922.
“Ozone in the St. Louis Schools” on Google Books to read the entire write-up in the Journal of American Society of Heating and Ventilation Engineers. Those schools added low levels of ozone to occupied buildings, which is not something we recommend. An ozone shock treatment of unoccupied rooms is the safer approach.
We do not recommend adding ozone to any occupied space. What we do recommend is what that teacher in Louisiana did: ozone shock treatments late at night while the classroom is empty, with enough time to air out before anyone returns.