Ozone and oxygen
O3 disinfection cycle
A period in which ozone gas is deliberately circulated through an enclosure with no one inside to reduce microbial contamination on surfaces and in air. Effectiveness depends on ozone concentration multiplied by contact time, on humidity, and on how much organic soil is present.
Also called ozone disinfection cycle, ozone shock treatment
What ozone does to microbes
Ozone is a strong oxidant and damages microbial membranes, proteins and nucleic acids on contact. The literature measures that effect as a dose: concentration × contact time, at a stated humidity, against a stated organism.
- Tseng and Li (Journal of Environmental Health, 2008): viruses on surfaces needed 20–112 mg/m³·min for 90% inactivation, 47–223 mg/m³·min for 99%.
- A 2023 field trial in Science of the Total Environment: 3.65-log reduction of a surrogate coronavirus and 4.73-log of Staphylococcus aureus in a public bus, efficacy tracking exposure time and humidity.
- Kim, Yousef and Dave (Journal of Food Protection, 1999): inactivation slows sharply when organic matter is present, because ozone is consumed oxidising it — in a sauna, sweat and skin oils.
The automatic cycle on the Red Light
Every Salvagente sauna has disinfection options, always run with no one inside the sauna. The Red Light has an automatic ozone disinfection cycle: you start it with one tap on the screen, it runs with no one inside the sauna, between sessions or whenever time allows, and the sauna shows a warning for the cycle. Ozone is a recognised disinfectant, and that is what the cycle is for.
It works alongside your cleaning routine rather than in place of it. That last study above is the reason: ozone is used up oxidising sweat and skin oils before it reaches anything else, so a sauna that has been wiped down gives the cycle much less to work against.
The routine that goes with it
Wipe the sauna down after every client, clean weekly with soap, warm water and a soft cloth, and disinfect to your health authority’s standard for shared equipment. The cycle is a useful addition to that routine, and a convenient one to run between bookings.
Why it matters here
If you run a spa, this is a feature clients notice and ask about. On the Red Light it runs automatically, started with one tap, with no one inside the sauna between sessions; the wipe-down after each client is still what keeps the sauna clean.