At low concentrations, ozone is not harmful to people or pets, but it can be lethal to microorganisms, such as bacteria, viruses, and mold. In any case, ozone is harmful if handled improperly, just as any other strong oxidizing agent.

For occupied spaces and food and water sanitation, the federal government has specified safe ozone limits. In addition to this, we recommend the use of proper monitoring equipment to further ensure safety.

OSHA Recommendations

Occupational safety and health regulations call for standard exposure limits for ozone in the workplace to be no more than 0.1 ppm averaged over an eight-hour period. On the OSHA website, you can find more information about the guidelines that OSHA provides for exposure limits, which may differ from those set forth in the standard depending on the length of exposure.

Unlike OSHA regulations, NIOSH safety and health standards are not enforceable under US law.  

The NIOSH recommended exposure limit for ozone is 0.1 ppm (0.2 mg/m3). According to NIOSH guidelines, Ozone levels of 5 ppm or higher are considered immediately dangerous to life or health.

The Ozone Material Safety Data Sheet (MSDS) describes health effects associated with higher levels of ozone, such as:

A person exposed to ozone can experience dry mouth, coughing, irritation of the nose, throat, and chest as well as headaches, fatigue, and labored breathing. However, only extremely low concentrations can create the sharp, pungent smell. Moving into fresh air and loosening clothing around the torso will help to relieve difficulty breathing. Seek medical attention if breathing is still difficult.

Ample washing with soap and water is recommended to prevent absorption through intact skin.

Contact with the eyes: Ozone can cause minor inflammation and irritation to the eyes. Corrective measure: Flush eyes thoroughly with water for at least 15 minutes, while holding the eyelids apart to ensure that the entire eye surface has been thoroughly flushed.

USDS & FDA Regulations


Food safety is regulated by the USDA and FDA. Ozone has been granted GRAS (Generally Recognized as Safe) accreditation by both agencies for direct contact with foods, including all meat and poultry products. Further, ozone has been approved for use in growing and producing organic foods by the USDA National Organic Program, and although adequate manufacturing procedures are required, there are no regulations on levels of ozone used in food processing.

In addition, the FDA also regulates the use of ozone in medical devices. The FDA has set a standard for ozone production in indoor medical devices no higher than 0.05 parts per million.