Poor cabin air quality is causing sometimes life-threatening conta-gious diseases among an increasingly large number of airline passengers, studies show. It was recently proved that tuberculosis can be easily transmitted through recycled cabin air. Last year, health-related incidents killed more aircraft passengers than air crashes, although diseases and infections are just part of an armoury of potential health problems that can occur in flight.

EBAN contacted business aircraft manufacturers to find out what measures are in place to protect the charter client from contagion. We found heartening news for business jet users across the board.

In modern airliners, recycled air is likely to be half fresh air, half recycled air, renewed every 10-12 minutes. Raytheon and Gulfstream do not use any recycled air at all, they said, but provide fresh air, made up of cold ambient air and warm bleed air from the engine, regularly.

Raytheon use a constant flow pressurisation system, according to manager of marketing communi-cations Kevin O'Hara. The air flow is linear to the cabin, and comes through the environmental systems to maintain temperature by using bleed air from the engine cowlings, and it flows back towards the outflow valve. "In a King Air, for example, we change the air every five minutes," O'Hara said, adding that, in a Beechjet, the air flows in from the rear of the aeroplane.

Keith Mordorf of Gulfstream told us that "our aircraft offer 100 per cent fresh air all of the time. Most aircraft recirculate air to achieve better fuel efficiency. We do not need to do this to achieve our desired performance. We also offer the lowest cabin altitudes. Even at the 51,000 feet maximum altitude for the GV, the cabin altitude remains at 6,000 feet - well below commercial airliners. This also helps passengers feel more refreshed after long flights," he noted.

Dassault's technical personnel were unavailable to speak to us about their business jets. However, while emphasising that he was not an expert, Pierre-Henry Messiah, marketing manager for Dassault Falcon (whose brother is by chance an epidemiologist), had this to say:

"One of the things we have seen in tourism is tropical diseases coming into Europe, specifically malaria. Statistically, the cabin volume of a wide-body aircraft is big enough to have enough mosquitoes come inside, such that one or two survive. This is not at all a problem on business jets.

"I am very cautious about those type of reports," he continued. "I don't think you can say that it (a disease) comes from the aircraft. It could be something the person has eaten, but brought on by the altitude."