The method for analyzing an ozone concentration comprising the steps of: providing at least one catalytic chamber having an ozone decomposition path between an inlet portion and an outlet portion thereof; receiving a sample flow of gas containing ozone by the inlet portion of the at least one catalytic chamber and along the ozone decomposition path; decomposing a totality of the ozone of the sample flow of gas into oxygen in an exothermic reaction along the ozone decomposition path of the catalytic chamber; measuring a first temperature value at a first position and measuring a second temperature value at a second position, the first and second positions being associated with the inlet and outlet portions; evaluating the ozone concentration of the sample flow of gas based on the temperature difference between the second temperature value and the first temperature value and calibration data; and generating a signal indicating the evaluated ozone concentration.