Posted By Bob Matthews AIIRSM Here's one for you. With the recent outbreak of legionaires disease, can anyone tell me if it is possible to get legionaires disease from a car air conditioning unit? and what would this mean for employers if this was a company car? and not maintained All the best Bob

Posted By John Webster Nick Quite correct. Legionella is a naturally occurring water-borne organism which multiplies in closed warm water circuits. Cooling water circuits are generally highest risk, and may contain open cooling towers which allow an aerosol of the water to disperse and be inhaled. Some large air conditioning systems use a water circuit as the cooling medium, and may spray water into the air to increase humidity. Air conditioners 'per se' are not a source of Legionnaires' disease. One was suspected of being the origin of the original American Legion outbreak in a Philadelphia hotel, but the water in the hotel is now believed to have been the cause. Car air conditioners are "dry", using the same type of refrigerant as a domestic 'fridge.