Earlier this week, we covered the story of two Mac users whose AppleCare warranty was voided simply because it was used in a smoking home. In one instance, Apple said the presence of cigarette tar presented a biohazard. In the other, it claimed that the substance caused damage to an iMac’s hardware. Is there any proof behind this claim?

In short, no, but cigarette computer smoke isn’t exactly the best thing. While smoke itself usually flows up away from the system unit, over time the air in the room housing it will become full of contaminants. This dirty air will then enter the computer through the intake fans. Eventually, the components will be covered in a small layer of sticky tar.

It’s not the tar itself that causes problems, but the the dust it attracts. Computers operated in the homes of smokers tend to gather dust and dirt more quickly. This isn’t likely to cause major damage, but dust can trap heat and slightly decrease hardware life span.

As far as I’m concerned, there’s no need to worry about smoking around a computer. Smokers might want to clean the inside of their machines regularly to mitigate the effects of cigarette tar, however.