Private vehicles must now be smokefree if they are enclosed, there is more than one person present and one of them is under 18. So it is an offence:
for a person of any age to smoke in a private vehicle that is carrying someone who is under 18
for a driver (including a provisional driver) not to stop someone smoking in these circumstances
The rules don’t apply to e-cigarettes (vaping).
2.1 Penalties The fixed penalty notice fine for both offences is £50. Somebody who commits both offences can get 2 fines.
Private vehicles must be carrying more than one person to be smokefree, so somebody who is 17 and smoking alone in a private vehicle isn’t committing an offence. Enforcement officers (usually the police) will use their discretion to decide whether to issue a warning or a fixed penalty notice, or whether to refer an offence to court.
2.2 What classes as an enclosed vehicle The legislation covers any private vehicle that is enclosed wholly or partly by a roof. A convertible car, or coupe, with the roof completely down and stowed is not enclosed and so isn’t covered by the legislation. But a vehicle with a sunroof open is still enclosed and so is covered by the legislation. Sitting in the open doorway of an enclosed vehicle is covered by the legislation. The rules apply to motorhomes, campervans and caravans when they are being used as a vehicle but don’t apply when they are being used as living accommodation. The rules don’t apply to:
boats, ships and aircraft, as they have their own rules
work vehicles and public transport, as they are already covered by smokefree legislation
2.3 Why the law has changed Every time a child breathes in secondhand smoke, they breathe in thousands of chemicals. This puts them at risk of serious conditions, such as meningitis, cancer and respiratory infections such as bronchitis and pneumonia. It can also make asthma worse. Secondhand smoke is dangerous for anyone, but children are especially vulnerable, because they breathe more rapidly and have less developed airways, lungs and immune systems. Over 80% of cigarette smoke is invisible and opening windows does not remove its harmful effect. The law has changed to protect children and young people from such harm.