A new anti-microbial air filtration system which will improve the environment of aircraft cabin interiors will begin in-service flight tests in the USA in May, with certification and production to follow by September.

Development of the Donaldson HEPA (high-efficiency particulate air) Plus system was prompted by discoveries that micro-organisms, such as bacteria, fungi, yeast, mould and mildew, can grow on aircraft filters and re-circulate through the aircraft. The research was conducted by Environmental Defense Technologies which joined forces with Minnesota-based Donaldson to develop the new filter.

The HEPA filter contains a built-in Microban anti-microbial agent which inhibits the growth of the micro-organisms. The agent penetrates and disrupts the micro-organism's cell walls, rendering them incapable of reproduction. Donaldson says the HEPA filter is 99.97% efficient at removing all particles sized 0.3 microns - the most difficult size to capture.

Virgin Atlantic Airways is among airlines due to test the filters in service. Two units will be fitted to a Boeing 747-400 for a C-check cycle, with regular inspections of the filters to assess colony counts. Two unidentified US carriers are also lined-up for trials.

Source: Flight International