From October 1 2015, it will be illegal for retailers to sell e-cigarettes or e-liquids to someone under 18; for adults to buy tobacco or e-cigarettes for someone under 18 and to smoke in a car or other vehicle when someone under the age of 18 is present. What are the rules on smoking in my car? ALL private vehicles must be smokefree if they are enclosed, there is more than one person present and one of them is under 18. It will be an offence for a person of any age to smoke in a car with anyone under 18 present.