You can't light up a cigarette in a restaurant or public place in many places including Maryland.
And those smoking bans seem to be saving lives.
Researchers looked at hospitalization numbers and death rates for respiratory problems.
They compared the stats before and after smoke-free laws were put in place.
What they found is hospitalizations for heart attacks fell by an average of 15%.
And hospital stays for respiratory disease fell by 24%.
- Information from CNN