Leave a small gap in the window, say experts

Cool comfort: A mother switching on the air-conditioner in her children’s bedroom.

PETALING JAYA: You’ve heard it from time immemorial. But it’s worth repeating even in 2020. “Get some fresh air!”

Experts have cautioned about health concerns linked to poor indoor air quality (IAQ).

Malaysia Green Building Council chief executive officer Tang Chee Khoay said fresh outdoor air was needed as it had the potential to impact a person’s performance whether at work or in school.

Those who slept with air-conditioning turned on throughout the night might wake up feeling “not sharp” and those who worked in a room with closed windows might feel easily tired due to increased carbon dioxide (CO2) levels, he said.

Hence, Tang said it was important to allow a small gap of fresh air to enter a room.

“Fresh air is dependent on leakages when you open the door, windows or some cracks between the doors to replace the oxygen which has been consumed.

“People often claim that putting indoor plants in the house replenishes oxygen, but you actually need a lot of it. One or two pots will not help, ” he said.

As most commercial buildings are fitted with a centralised air-conditioning system, Tang said those systems are designed to allow fresh air in from the outside.

But he lamented that most people chose to close the outdoor air-conditioning vent to save cost.

“There must be a balance in allowing outdoor air in, ” he said.

Asean-Air Conditioning and Refrigeration Association (Asean–ACRA) president Datuk Seri Dr Ricky Yaw concurred that there must be a balance in the usage of air-conditioners.

He believes that air leaks through doors, ceilings and windows were sufficient for normal households while those with fixed windows might notice “stuffiness” in their house due to the high CO2 levels from isolated air circulation.

“High CO2 levels will make you feel very sleepy and stuffy. Even in vehicles, it is better to open the (outdoor air-conditioner) vent as a person will feel better, ” said Yaw, who is also the Malaysian Air Conditioning and Refrigeration Association immediate past president.

William Rodney Yeo, the managing director for Airestec, a life and environmental sciences eco-friendly company that addresses indoor air problems, urged people to service their air-conditioners at least once a year to ensure good IAQ levels.

“Air conditioning systems deteriorate (when coils are not cleaned) which leads to greater energy consumption because airflow is reduced which then sees humidity levels go up, ” Yeo said.

Yeo noted that the conventional methods of cleaning air-conditioners with acid and alkalis should change too, adding that it was bad for the environment.

He suggested using eco-friendly methods such as bio-enzymes.

The Alliance for Safe Community chairman Tan Sri Lee Lam Thye said a typical level found in spaces with good air should be from below 350 to 1,000 ppm.

Anything more than 1,000 to 2,000 ppm, was associated with drowsiness and poor air.

And levels from 2,000 to 5,000 ppm were generally associated with headaches, sleepiness, stagnant, stale, and stuffy air, he said.