A member recently asked us about an email they’d read that advised them to always open their car windows before turning on the air-conditioning on a hot day. The email claimed that the air-con system would circulate high levels of the chemical benzene unless the window was opened first.
Benzene, a hydrocarbon, is used in petrol to improve its detonation properties. Most experts agree it is a harmful chemical linked to anaemia and leukaemia, and its use is strictly limited in most countries including Australia.
Benzene is also used as a solvent in some glues, and this has led to the claim that benzene fumes are emitted from the adhesives used to bond car interior trims together.
Benzene is volatile, which means it forms a gas at relatively low temperature, but this also means that any residual presence in trim is likely to be short-lived and in low concentration. Vehicle trim is therefore unlikely to be a source of significant long-term benzene exposure. In any case, ventilation of the car prior to running the air-con would not make much difference.
But that’s not to say that opening your windows is a bad idea before heading off. I once had a Ford Focus with an ‘auto window down’ feature operated from the remote. It was the best thing for getting rid of hot stuffy air after a day in the Aussie sun. It would be good to see more cars with this feature.
Submit your questions to RoyalAuto, Level 9, 485 Bourke Street, VIC 3000 or firstname.lastname@example.org.