Even ozone as air cleaners can cause lung problems according to
Consumer Reports when they last looked into this problem. A commercial
ozone generator could easily be several orders of magnitude greater
than the household units CR was evaluating - don't know without the
specifications. Ozone dissipates but could enter the house since it's a
gas. I would ask the local health authorities about quantities of ozone
and crawl spaces and what not. Short answer, keep all living creatures
away if using enough ozone the place to kill tough mold.