US takes world to the cleaners

Scientists are taking air pollution detection to a new level with a room-sized environmental test chamber capable of measuring ultra-trace concentrations of airborne chemicals.

Scientists at the Georgia Tech Research Institute (GTRI) are taking air pollution detection to a new level. They have built a room-sized environmental test chamber incorporating more than a dozen smaller chambers and a mass spectrometric centre able to measure ultra-trace concentrations of airborne chemicals being emitted from products.

The chamber will help manufacturers meet new international standards to minimise indoor air pollution, said Charlene Bayer, principal research scientist at GTRI's Health and Environmental Systems Laboratory. 'Because US manufacturers sell their products worldwide they must meet emission regulations imposed by nations in Europe and Asia,' she said. 'We make the measurements companies need to improve their products.'

The 27.5m3 environmental chamber will also allow researchers to study broader concerns — including the impact of low-level indoor air pollutants on productivity and human health.

Samples taken from the chambers are analysed by four mass spectrometers designed for different types of identification. One instrument is used to analyse light gases such as carbon dioxide, produced by the respiration of living organisms. Another is designed for proteomic and other biomedical research. The instruments can measure chemical compounds in femtogram-level quantities.

The facility also includes gas chromatograph/mass spectrometer combinations. For testing the efficiency of air filtration systems Bayer uses a smoking machine that helps simulate a smoke-filled environment, and it can also test the efficiency of other equipment designed to clean the air.