Short answer: ozone (O3) is unstable and turns back into ordinary oxygen (O2) on its own. About half of it is gone within half an hour of being made, so ozone cannot be bottled and stored. You make it at the time you need it.
Where the ozone goes
Nowhere. Ozone is three oxygen atoms bound together, and that arrangement does not last. As it breaks down, it simply turns back into oxygen. During that change a free oxygen atom is released, which is highly reactive and short lived, surviving only milliseconds under normal conditions. That reactivity is what makes ozone such a strong oxidizer.
How fast it breaks down
In the gas coming off a generator, about half of the ozone is gone within half an hour. In water it can break down anywhere from a few seconds to around 30 minutes, depending on the water chemistry, its pH and its temperature.
What this means in practice
- Make ozone on demand. This is why ozone generators exist: if you want ozone for drinking water, a hot tub, a swimming pool or any other purification use, the most effective way is to make it yourself from oxygen at the time you use it.
- Use ozonated water soon after making it. Its strength drops as the ozone turns back into oxygen.
- Do not run more ozone than you need. It will not keep for later.
Why make it from pure oxygen
Air is about 21% oxygen. Feeding a generator pure oxygen from a tank or concentrator lets it reach much higher concentrations, which some applications need. Our WPS-100, WPS-400 and WPS-120 are all designed to be fed with oxygen.
Questions we get asked
Can I store ozone in a container for later?
No. It turns back into oxygen; about half is gone within half an hour.
Does ozone leave anything behind in water?
As it breaks down it turns back into oxygen. In water treatment, ozone also turns iron, manganese and sulfur into particles that are then filtered out.
What does ozone smell like?
Ozone is a colorless gas with an odor like the air after a major thunderstorm.
A note on safety
Ozone is a strong oxidizer and it is harmful to breathe. Run your generator in a well ventilated room, keep the ozone inside tubing and closed containers, never breathe it directly, and follow the instructions that come with your unit.
