Ozone & Cold Water: A Perfect Match

Updated: Apr 12

The most powerful and safe disinfecting agent available for water treatment systems is ozone -- more powerful than chlorine and bromine, and safer because it consists only of pure oxygen. Ozone is a chemical rearrangement of O2, the usual form of oxygen in the atmosphere, into a less stable, more powerful combination of three oxygen atoms, O3. The third oxygen atom is what makes ozone such a strong oxidizing agent. It is the oxidizing power of ozone that destroys pathogenic bacteria and viruses, and cleans the water by attacking other organic compounds like algae, and old skin cells. Ozone even destroys pollutants like benzene, toluene, xylenes (BTX), methyltertbutylether (MTBE), and volatile organochlorinated compounds. It even destroys the deadly ebola virus (Davies 2015).

In short, ozone is terrific for cleaning water, which is why it is used in the most advanced drinking water treatment plants in the world.

So why isn't it used in swimming pools and in your municipal drinking water distribution system? Why do our drinking water engineers and pool health standards till poison us with chlorine, and the byproducts of its use (like toxic trihalomethanes).

The problem with ozone is its instability. Even without something to react with, ozone as O3 will devolve back to plain O2 oxygen -- sometimes in seconds. So, even where ozone is employed for water disinfection, municipal treatment works will still add chlorine so that the there is always disinfectant in the distribution pipes. Chlorine is more stable than ozone, and so it maintains high concentrations for longer.

That's also why ozone isn't used in swimming pools, because unless you produce ozone 24 hours a day, 7 days a week, most pools would lose all their ozone to natural degradation less than an hour after the pool pump turns off. And even with constant production, maintaining ozone levels throughout the entire pool could be difficult during the warm summer months, when ozone degrades fastest, leaving the pool water vulnerable to infection. By contrast, chlorine will last until the pool pump comes back on the next day. In that way, chlorine is safer for warm water.

However, Morozko doesn't want chlorine, because it smells awful, it's poisonous, and it isn't good for bathers, or compatible with the other materials in the tub. Morozko wants ozone, because ozone is the best for cold water.

Some hot tubs and swimming pools will use ozone, too. In fact, the equipment that we install in the Filtered Forge was originally designed for hot tubs, spas, and swimming pools. We've done little more than adapt it for ice baths.

And it turns out that the cold makes a big difference.

High concentrations of ozone disinfect water very fast. It takes little more than seconds at ozone saturation levels to destroy even the strongest viruses. But in hot water, ozone has two disadvantages:

1. The saturation concentrations of ozone are much lower, because the hot water temperatures boil the ozone out of solution and into the air.

2. The heat speeds up the ozone degradation.

Because the Forge is so cold, the disadvantages of ozone in hot tubs are advantages in the Forge. We get higher saturation concentrations in our ozone contact chamber, and the ozone stays around much longer because it is more stable in the cold. In fact, our measured results show that we maintain a safe, low-level residual concentration of ozone in the Forge whenever the filtration system is running. That's how the water in the Filtered Forge stays super crystal clear and safe, all the time.

The use of ozone in water is not controversial. However, ozone in the air can be either beneficial, or problematic. The United States Environmental Protection Agency recognizes airborne ozone as a toxic pollutant, because it is such a strong oxidant that in high enough concentrations it a