Ask 'Dr. Spa' Q & A Message Board

: I'm not exactly sure what you are getting at, and I'd have to review my
: college chemistry to answer this with certainty, but it seems to me
: that O3 is looking for any molecule available to combine with.
: Sometimes it will bump into another 03 and make 3 O2s. However, since
: air is primarily composed of nitrogen, it will also combine to make
: nitrogen compounds. When it encounters carbon, same thing. Its
: ability to combine with carbon is what allows it to theoretically
: oxidize/sanitize in the tub. The issue is how much of it dissolves
: into the water in order to accomplish that. The majority of the O3
: likely offgasses or combines with nitrogen compounds in the tub, so I
: don't think skin absorption is an issue, nor ingesting, unless you
: drink a lot of tub water. I suppose if you were to breathe in enough
: of the off-gassing, it could cause some degeneration in the lungs,
: but I suspect the ozone disperses quickly enough after the bubbles
: break the surface that it is of little concern -- unless the tub is
: in an enclosed enviroment, without adequate ventilation.

My personal opinion on all this, and this is just an OPINION as a firefighter, is that I'd worry more about large doses of chlorine run-off (or Bromine fumes) vs. this ozone question. Use of the Ozone treatment reduces the need for chlorine, since it lets the ozonation of the water do the oxidation, and leaves the chlorine with only the job of anti-bacterial work. Using less chlorine means less chlorine gas and buildup.

A side story to all this is that my personal pool (back in my desert days) was showing zero chlorine. Of course, I went over to the deck-chlor to see what was up, since I just droppped two large tabs in the bucket. I open the lid and look in (real close) to discover that the water was not flowing. Just then, I took a nice deep breath of concentrated chlorine gas. GOOOD times indeed as I fought to get a breath for the next 15 seconds.

As it turned out, my kid had gone by the pump housing and shut off the water flow to the deck chlorinator.

So after all this, my take is less Bromine/chlorine=good. More ozone? Who knows.