Boston city officials are stepping up efforts to regulate electronic cigarettes that deliver nicotine and individual cigars that have become popular with people looking for cheaper alternatives to cigarettes.

E-cigarettes are battery-powered plastic and metal devices that heat a liquid nicotine solution in a disposable cartridge, creating vapor that users inhale.

The Boston Public Health Commission on Thursday approved a proposal to immediately treat e-cigarettes like tobacco products. That includes requiring retailers to obtain permits to sell them, banning their use in the workplace and restricting their use to adults.

The board also approved banning the sale of single-sale cigars by requiring that they be sold in their original manufacturer packaging of at least four. The rule becomes effective at the end of January.

The board also doubled fines for retailers that violate tobacco control regulations.