Secondhand smoke in homes: A bigger problem than Singapore authorities think?

Secondhand smoke in homes: A bigger problem than Singapore authorities think?

How far can cigarette smoke travel between flats? How much secondhand smoke is enough to start affecting your health? Is regulation the only option? The programme Talking Point looks for some answers.

SINGAPORE: He has approached his town council and the Housing and Development Board (HDB). He also tried speaking to his neighbour “on many occasions”.

But “Mr Ng” is at the end of his tether now, with no resolution in sight.

The cause of his problems: Secondhand smoke filtering into his flat from his neighbour’s balcony, “just a metre away”.

“(HDB flats) aren’t that big nowadays … From the living room, (the smoke) quickly gets (into) the entire unit,” said “Mr Ng”, who requested anonymity because his neighbour lives right next door.

“I can’t leave the (balcony doors) open without having to run to the living room to close (them) when we smell smoke and then to air out the house with fans.”

He also installed rubber seals on all the windows and doors, since he has a young child. But even with those precautions, he worries about how much secondhand smoke his 22-month-old daughter might be inhaling.

The agencies he approached have advised his neighbours not to smoke near the balcony and windows, he said, but they “maintain their right” to do so and that “there’s no way they could control where the smoke would end up”.

The number of such complaints about secondhand smoke in homes has risen during the pandemic, to about 150 to 200 each month from 60 to 80 complaints a month in 2018 and 2019.

And immediate neighbours of smokers may not be the only ones concerned. In a look at the extent of the problem, the programme Talking Point found out that the smoke particles can travel across 10 storeys.

This is according to simulations carried out by Zheng Kai, a faculty fellow in architecture and sustainable design at the Singapore University of Technology and Design.

The simulations are based on two blocks 18 storeys high, about 30 metres apart at their widest and located in Buangkok, an estate representative of flats built in the 2000s.

On a still day, “what’s likely to happen is that the smoke particles would just hover around … without settling on the ground”, said Zheng.

“The neighbours in the immediate proximity — maybe just below the smoker, above … and then around him — will most likely be able to smell the smoke.”

But on a windy day, when someone on a lower storey is smoking, the smoke particles may be “carried upwards into a vortex”.

If a smoker is on an upper storey, the same wind would form a vortex that carries and circulates the smoke downwards. “In this case, the neighbours below are all getting the smoke,” said Zheng.

It takes “as short as maybe one minute to a few minutes” for the smoke to dissipate.

The most important factors in determining how far the smoke can travel before that are the buildings’ relative heights and distance between them, as well as the wind direction, he added.

It does not, however, depend on “whether the smoker is smoking in the living room, by the window or on the balcony”.

“No one smokes with their windows closed, and … many households have ceiling fans,” Zheng said. “What that means is that the smoke is dispersed in … small concentrations in all directions.

“All the neighbours in the immediate vicinity would be able to smell the smoke … I’d say perhaps the best solution is to not smoke at all.”


As far as Member of Parliament (Nee Soon GRC) Louis Ng is concerned, the way forward is to bring in government regulation. Twice in Parliament, he pitched a ban on smoking at home near windows and on balconies.

Source: CNA