Iceland volcanic ash and my PC

[axel]

Greetings!

I run a Dell Inspiron 1501 with Ubuntu 8.04. and I live in London where
the air pollution is so bad you dont need to smoke to be a candidate for
all kind of breathing problems.

About a year ago I had a Dell Service Tech replace the Dell PC fans ,
filters and a few other bits and pieces : due to the fact that the PC
was crashing due to high Temperature.
His recommendation was to blow high pressure purified air into fan
intakes.

Further reading on the subject , I found the opposite opinion :that was
the last thing you should do, as it blows all the dust inwards...past
the filters and into the system.
i.e. in other words the remedy lies in using a vacuum cleaner and point
it at the fan intakes. 

Now with all this ash coming my way...

I would appreciate your thoughts on the subject,
Cheers,
Axel.