Qualified ozone sterilizers have low ozone levels and are not harmful. If the ozone content is high, it may cause some harm to human body. Most ozone sterilizers are low-temperature disinfection, usually using the strong oxidation of ozone to kill bacteria. Ozone can spread quickly and evenly in the air, so it can be sterilized in all directions. Generally qualified ozone sterilizer in the ozone content is relatively low, so it does not cause harm to the human body, it is recommended that the use of windows should be opened regularly to ventilate, and regular inspection and maintenance. If the ozone concentration is too high, up to 0.1 ~ 0.2 mg per cubic meter, it may cause some harm to the human body, there will be a sore throat, headache and other symptoms.