If any person, firm or corporation shall violate any of the provisions of this article, as amended from time to time, or shall do any act prohibited herein, or shall fail to perform any duty lawfully enjoined, within the time prescribed by the fire chief, or shall fail, neglect or refuse to obey any lawful order given by the fire chief in connection with the provisions of this article, as amended from time to time, for each such violation, failure or refusal, such person, firm or corporation shall be fined in any sum not less than twenty-five dollars ($25.00), nor more than five hundred dollars ($500.00). Each day of such unlawful activity as is prohibited by the provisions of this section shall constitute a separate offense.