30. Whoever hinders or attempts to hinder or in any way impede an inspector or a sanitary physician in the execution of the duties of his office is guilty of an offence and liable, in addition to costs,(a) in the case of an individual, to a fine of not less than two hundred dollars nor more than six hundred dollars;
(b) in the case of a corporation, to a fine of not less than five hundred dollars nor more than two thousand dollars;
(c) for the first subsequent offence within two years, to a fine the amount of which shall not be less or greater than twice the fines provided for in subparagraph a or b, as the case may be;
(d) for any other subsequent offence within two years, to a fine the amount of which shall not be less or greater than three times the fines provided for in subparagraph a or b, as the case may be.