The beginning of year 2020, the COVID-19 pandemic has hit all parts of the world, including Indonesia. This pandemic is caused by the SARS-CoV-2 virus and its various mutants and variants. This virus is known to attack the human respiratory system. The virus is transmitted through direct contact or through the air, which makes it Airborne. Even though there are variety of disinfectants that can prevent transmission between humans, not many can maintain the sterility of the room continuously. Disinfectants on its own have a level of danger to humans when exposed at a certain doses and for a certain time. Ozone (O3) is known as the most potent disinfectant. This paper is intended to determine the appropriate placement and dose of Ozone when used in a meeting room at an office, which is widely known as the centre of the Covid-19 spreading in Jakarta, using the Prevention through Design (PtD) method. In designing the right Ozone placement, the existing air system will also be studied. The calculation of the levels of O3 is based on mathematical calculations. The result from this study shows that the positioning and dosing control of O3 can effectively disable/kill the virus, while still considered safe for humans, so that productivity will be maintained.