It is important to kill mold because it is a very hardy organism that can thrive almost anywhere and everywhere that humans live. Mold spores can be found in the very air that we breathe, and are able to reproduce rapidly when they are deposited on surfaces that have a great deal of moisture on them. Even surfaces that you think are perfectly dry may actually have a great deal of moisture because moisture is present in air all the time (except in very arid environments.) It is more likely for mold to grow in places that do not have adequate ventilation, such as enclosed hospital operating rooms and food processing plants with little or ventilation. That is why hospitals and food processing plants routinely use ozone generators (also known as ozone machines) to kill mold.

To kill mold, the ozone treatment team will ask you to remove all people, pets, and even houseplants from the room; that is how strong ozone is at killing organisms. But since your aim is to kill mold, even plants should be physically removed from the room. The room will eventually be fully enclosed to prevent people outside the room from inhaling the toxic ozone.

The second step to kill mold is to remove as much moisture and humidity from the room as is feasible, even going to the extent of using a dehumidifier. The dry room that results will help ozone do its work better.

The team will then use gloves and a mold killing solutions to physically remove any observable traces of mold on your room surfaces (including the ceiling.) Gloves and other physical forms of protection like goggles and face masks are very important so that the team will not be contaminated by any contact with the mold growth.

The ozone level that should be produced will then be determined based on how much time is estimated to be needed to kill mold that remains, the degree of contamination of the room, and how quickly ozone can break down after being released into the room's air. It is believed that a very strong ozone generator should be used for best results in as short a time as possible. A small machine cannot produce the amount of ozone needed to kill mold as thoroughly as necessary.

All ozone generators used should have a built-in timer so that the team will know when the machine has been turned off. It is very important the ozone be allowed to ventilate out of the room air before anyone can breathe it. Remember, ozone, though not nearly as bad as chlorine or fluorine is toxic when inhaled in large concentrations.

If the room is deemed safe to enter again, leave the room occupant-less for perhaps a day then try smelling the air and inspecting the walls again. If you still smell mold or can see them growing on your room surfaces, more ozone blasting sessions might be required. You can also take an air sample using a mold test kit and have it analyzed in the lab to insure the mold has been removed.