Posted By Calum R Cameron Hi all, An employee of the company has raised a query regarding servicing of cars and other vehicles with air conditioniong. He has asked whether there is a risk of legionella being present in the coolant etc. Has anyone heard of this before or had experience of it as I, quite honestly don't know the answer. Looking forward to hearing the advice of the forum. Many thanks. Calum

Posted By Phil.D.Baptiste Callum, I spent 14 years in the motor trade, on the spanners, and I have NEVER heard of a case either on the engine coolant/cabin heater side or, even less likely on the gassed air-con side.... I would however, also like to know if there is a possibility when the new gas/refridgeration alternatives are in use.... Philby

Posted By Pete Moran The spelling gremlin is about today!....Legionnaires what what I meant to write!

Posted By John Webster The association of Legionnaires disease with certain types of air conditioning system has given rise to the belief that all sorts of air conditioning can cause Legionnaires disease. This is just not so. Legionella is a bacterium commonly present in water. For it to become harmful it has to *multiply *be inhaled To multiply it needs warm (20-45deg C) temperatures and preferably somewhere to hide, like deadlegs and sludge/scale deposits. These conditions are most likely to be found in water circuits like in hotels, hospitals, office blocks etc., where even the cold water may end up supplied at room temperature, and in secondary cooling circuits, like those at power stations and certain types of other large scale cooling and air conditioning systems. Inhalation from a water circuit is usually from shower heads, although spray taps can be implicated, and from open circuit cooling towers - those where the water is allowed to cascade in an updraft of air, (producing the characteristic clouds). Most small scale aircon systems, including cars systems, work like the domestic 'fridge. The refrigerant is a chemical, liquid when compressed and gas when not. It's a sealed circuit, and in no way resembles anything which poses a legionella risk. One caveat, air conditioning might include re-humidification. If so, this should be risk assessed for legionella.

Posted By Laurie Forget the coolant, which as has been rightly pointed out, is sealed. A/c produces condensed water as it dehumidifies the air, and you will often find a pool of water under the car. If any of this water fails to drain, and lies static somehwere in the nice optimum temperature of the engine compartment, can it be picked up and "aerosolled" by the blower? Laurie

Posted By Stuart Nagle Calum. As far as I am aware the systems in cars are 'closed' systems where heat/cold are transferred via fans and airflow across hot or cold surfaces only and so should not represent a hazard, however I stand to be corrected. Stuart