Council members voted to amend part of the ordinance Monday night.
Council members voted to change the distance smokers must be from a business entrance from 15 feet to five feet.
The ordinance passed by a vote of 8 to 1.
Deputy Mayor Pat Jones was the only 'no' vote.
St. Joseph's smoking ban, passed by voters in April, went into effect on Saturday.
The ordinance bans smoking in all indoor public buildings including bars and restaurants except for the gaming floor of the St. Joseph Frontier Casino.