A purification arrangement for purifying a contaminated gaseous medium comprising: an ionizing equipment for ionizing air a supply pipe for the supply of contaminated air and at least one mixing chamber, wherein the contaminated air is fed through the mixing chamber in a main flow and ionized air is added to the main flow an inlet for introducing ambient air into the main flow of the contaminated gaseous medium prior to the mixing chamber a first temperature sensor arranged in the supply pipe prior to the inlet and configured to detect the temperature of the contaminated gaseous medium wherein if the temperature of the contaminated gaseous medium detected by the first temperature sensor is above 70° C., ambient air is added through the inlet into the main flow.