What does smoking in a car do?
Short answer
A car is the smallest sealed space people routinely smoke in, so smoke concentrations are far higher than for the same cigarette in a room. A lot of fabric and plastic surface in a very small volume means residue builds up quickly. Opening a window dilutes the smoke but does not remove what has settled.
Key points
- A car is the smallest sealed space people routinely smoke in.
- Smoke concentrations are far higher than in a room.
- Residue builds quickly on the fabric and plastic inside.
- Children in the back seat cannot leave the space.
Why a car is the worst case
A room has volume. A car does not.
Same cigarette, same amount of smoke, but a fraction of the space for it to disperse into. The concentration is correspondingly higher.
Residue inside a car
A car has a lot of fabric and plastic surface in a very small volume: seats, roof lining, carpet, door cards. Residue settles into all of it.
That is why a car smoked in holds the smell for a long time, and why it comes back more strongly in heat or humidity.
Who is affected most
Children in the back seat. They breathe faster than adults, so they take in more relative to body weight, and they cannot leave the space.
Opening a window
Dilutes what is airborne. Does not remove what has settled into the seats and roof lining.
The only thing that works
Not smoking in the car. WHO states there is no safe level of exposure to secondhand smoke.
If you want to stop altogether, the quitline is 1800 6606, free, 08:00 to 22:00 daily.
Common questions
- Is opening a window enough?
- It dilutes what is airborne but does not remove what has settled into the seats, roof lining and carpet. That is why a car smoked in holds the smell for a long time.
- Why are children in cars affected more?
- Children breathe faster than adults so take in more relative to body weight, and a child in the back seat cannot leave. WHO states there is no safe level of exposure.
Sources for this article
- Tobacco fact sheetWHO
- GATS VietnamWHO
- Law on Prevention and Control of Tobacco Harms (2012)National Assembly of Vietnam