Testing Ozone

[EChapple]

Can Ozone be tested in swimming pools? and how?? Using ozone generator not injector.

[UltraPure Water Quality]

EChapple,

My name is Brian, and I am the Sales & Service Manager at UltraPure Water Quality, Inc. We have been manufacturing UltraViolet (UV) Ozone Generators for Pools and Spas since 1982.

There is no "Ozone Test" available, as Ozone reverts back to Oxygen and does not maintain a residual in the water, although there are ways to test that the Ozone is working properly.

1. Use a D.P.D. Test Kit to periodically test for Free Available Chlorine (FAC) & Total Chlorine (TC). As long as the difference between Total Chlorine and Free Available Chlorine is less than 0.5ppm, the Ozone is doing its job (i.e. removing contaminants which form combines and use up chlorine).

2. If using Ozone, a Mineral Based Biostat or an Algaecide and Chlorine. Test for Total Chlorine (TC) only. The TC level should be maintained at about half the normal (regional) Chlorine level (TC=1.0-3.0ppm).

3. When products contain sequestering agents they tend to mask the Free Available Chlorine (FAC) level. Only the Total Chlorine (TC) reading is valid.

4. Periodically chech the pH level and maintain it between 7.2 and 7.8.

I hope this answers your question. Please feel free to contact me if you have any further questions, or would like information on any of our products.

[mackay]

You shouldn't have any ozone residual in the pool itself because it would tend to offgas at the water surface where the bathers breathe. You might have ozone residual in the circulating water stream, but not necessarily. If you want to check for residual ozono, Hach has a test kit.
A better measure of the oxidizing effect of the ozone is oxidation-reduction potencial or ORP. Several instrument companies sell ORP analyzers, which are very similar to pH meters. You should see an increase in ORP if you measure before and after ozone injection. An ORP of 600-700 mV going back to the pool is probably a good level.