The second-largest city in Kansas is adding electronic cigarettes to its ban on smoking in public places.

The expanded ordinance in Overland Park will take effect later this month. City Council members in the Johnson County community approved it Monday night.

Overland Park has prohibited smoking in hotel rooms, restaurants, workplaces and other public, indoor spaces for nearly a decade. The new ordinance adds electronic cigarettes to the ban.

The measure also makes it illegal to sell e-cigarettes to people under 18.

Council members disagreed on whether there’s conclusive research that vapor from electronic cigarettes is dangerous to smokers and to those exposed to it second-hand. Proponents of the ban said it was better to err on the side of caution.