Abstract: Portable ozone generators and methods of use. For example, a hand-held portable ozone generator has: a housing defining an air inlet, an air outlet, and an air channel communicating between the air inlet and the air outlet; a battery; an ozone generator configured to output, during operation, ozone into the air channel at a non-zero rate that is equal to or below 50 mg/hour; and a controller connected to send control signals to the ozone generator in response to user input. In other cases, a plank or slab shaped portable ozone generator is disclosed, with an air inlet and an air outlet located in respective opposed face plates. In one case the unit has no defined base, and every face and side wall of the device forms a ground engaging base, and the unit functions properly regardless of what face or side wall the unit contacts the ground or a horizontal ground surface with.