Not all air-cons filter fine particles

The haze situation has resulted in many Singaporeans seeking refuge in their air-conditioned homes or in malls.

While staying in an air-conditioned environment has its advantages, there can be drawbacks, going by what doctors and a retailer told My Paper.

Dr Madeleine Chew, a mobile doctor who sees patients in their homes, said air-conditioners have been shown to be useful in cutting down particulate matter, such as those found in the haze.

But air-conditioners may not be able to filter PM2.5 particles - particulate matter smaller than 2.5 microns - which are said to be more dangerous to a person's health than larger particles.

Gain City, one of the largest air-con retailers here, said that most air-con models boast a wide range of air-filtering properties.

But a check by the company on some major air-con brands that it carries showed that models either cannot filter PM2.5 particles or did not stipulate if they are able to do so.

Still, Dr Chew said that while air-con filters do not remove all particulate matter, closing all doors and windows have been shown to minimise the occurrences of lung and heart diseases associated with particulate matter.

Gain City advised that, during the hazy period, people should service their air-cons if they have not done so in a while. "This will ensure that the air-conditioner works efficiently to cool your rooms and clean the air".

People who are sensitive to dry air could be affected by prolonged exposure to air-conditioned environments.

Dr Gregory Leong, a general practitioner, said that such people may have symptoms like dry eyes, dry nasal passages and dry throats.

But Singapore's high humidity levels may mitigate some of the problems caused by dry air in an air-conditioned setting, he said.

To mitigate some effects of prolonged exposure to dry air, Dr Leong advised that people could place humidifiers in air-conditioned rooms.

Bowls of water could also be placed in the rooms to allow evaporated water to increase moisture in the air.

He said these measures "may help a little bit".

Undergraduate Andrew Lu, 22, said that his family's air-con usage has increased because of the haze situation.

But it has a side effect: His skin itches more and is more prone to becoming dry and scaly as it is sensitive to dry air.

He said it was still bearable, as "I have medication that heals and moisturises my skin".