Recirculating air to battle SARS
By Rosli Abidin Yahya

The World Health Organisation (WHO) through its website has confirmed that 17 people with Severe Acute Respiratory Syndrome (SARS) have been carried on aircrafts world-wide. An internal airline industry memo stated that three passengers or crew contracted the probable SARS in the air.

At least three suspected cases were on Air Canada flights. None of them turned out to be SARS. About 100 million people flew in March, making the infection rate very low.

Experts say SARS is not airborne, but they cannot be certain. Despite that, many travellers say they are worried about stale cabin air.

Most large aircrafts have outside air drawn in which is heated and compressed through the engines and mixed with at least 50 per cent recirculated cabin air. High efficiency filters called HEPA are supposed to screen out contaminants, including viruses.

However, WHO noted that some airlines, such as Royal Brunei turned off the recirculated air to increase the fresh air flow.

Boeing, whose aircraft are being utilised by Royal Brunei does not recommend that and airlines have balked at the cost. Fresh air costs more to heat and compress.

Boeing claimed that the current recirculation system on its aircrafts can prevent the spread of microbials such as SARS.

But experts on air quality and plants, says fresh air is the better way.

WHO said French aircraft manufacturer, Airbus Industrie, has told airlines to replace filters every time there's a suspected SARS passenger.

Courtesy of Borneo Bulletin