The Board of Trustees and Mayor shall have power to modify any of the provisions of the Fire Prevention Code upon application in writing by the owner or lessee, or his duly authorized agent, when there are practical difficulties in the way of carrying out the strict letter of the Code, provided that the spirit of the Code shall be observed, public safety secured, and substantial justice done. The particulars of such modification when granted or allowed, and the recommendation of the Chief of the Fire Department thereon, shall be entered upon the records of the Village and Fire Department. The Board of Trustees and Mayor may impose such conditions as they deem appropriate, in their discretion, prior to the issuance of any modification; and said modification may be revoked at any time in the event said conditions are not fulfilled, and continually complied with, by the applicant.