Most monitoring of air pollution is conducted outside, but statistics show in fact that Australians spend 95 per cent of their time inside... and this is where pollutants could be silently causing problems.

Dr. Tom Beer, a CSIRO scientist, from the Division of Atmospheric Research, was interested in discovering what the most heavily polluted areas he encountered during a normal day were.

So he devised a personal air pollution sampler which he wore for 20 weeks during his normal day to day activities.

He found from his sampler that nitrogen dioxide, which forms whenever fossil fuels such as natural gas or petrol burn, read at 16 parts per billion outside on a normal busy street. And as soon as he went inside his home, the reading dropped to 12 parts per billion.

However in the kitchen, where there is a gas stove, the reading leapt to 32 parts per billion, twice the reading outside the house.

"I see these being used in any situation where workers may be exposed to nitrogen dioxide and typical examples of that would be chefs working in an industrial kitchen, or workers in factories that have gas fired boilers. "

"We have similar passive gas samplers that can measure ozone, that can measure sulphur dioxide, that can measure formaldehyde."

There are currently two thousand samplers being worn around the world. The information collected from these will be used by environmental managers to ensure that we have clean air inside as well as outside.