Like to take a few puffs after your supper? If that truck stop is in Boston, think again.

This month, the state of Massachusetts instituted a ban on smoking in all workplaces, restaurants and bars in the state, the Department of Public Health announced. The ban took effect July 5.

Only a few places in the state are exempt, including some private membership clubs and “cigar bars.” Beyond that, anyone who lights up indoors at a public establishment could face a $100 fine, while business owners who let people smoke indoors could be fined $300.

People who have questions or concerns about the new non-smoking law or would like to file a complaint can call the state’s smoking law hot line, 1-800-992-1895. The line is available 24 hours a day.