In all such municipalities, no such building or structure shall be erected or used in whole or in part for said purpose of public amusement unless the plans and specifications therefor shall first have been approved by the commissioner of labor. Such plans and specifications shall be submitted, in duplicate, before any construction is undertaken. If they shall, in all respects, conform to the code mentioned in section 5:3-22 of this title, the said commissioner shall approve the same, retaining a duplicate copy of the plan in his department.