Skip to navigation | Skip to content  Jetsetting germs a
filtered fable   Model jet circling a globe  (Source:
iStockphoto/)  Last time, I talked about the common (but wrong)
belief that because commercial jet planes are the most squashy
place that people will pay to be herded into, the germs that the
passengers breathe out will infect everybody else onboard.  In
the early days of pressurising airliner cabins, around World War
II, the air was fed in, and then dumped, so that the passengers
breathed the air only once. This was very good for the
passengers, but it cost fuel, energy and dollars.  So the plane
makers introduced recycling of some of the cabin air, so that
they would need to bleed less air from the engines.  The
advantage of recycling air is that it saves the airlines about
$US60,000 per jet plane each year. The disadvantage is that the
passengers breathe air with higher than normal levels of carbon
dioxide. Other factors (such as low humidity) make the air not
quite as lovely as rainforest air.  T