N.Y.C. Charter § 491: Section 491. Orders of the commissioner; enforcement.

a. The commissioner shall have the power and it shall be his duty:

(1) To order in writing the remedying of any condition in violation of any rule or regulation or any provision of law which he is empowered to enforce.

(2) To cause any order of the commissioner which is not complied with within the time fixed in the order for such compliance to be enforced and to take proceedings for the enforcement thereof as may be provided by law.

b. Every order, requirement, decision or determination of the commissioner shall be in writing. The commissioner shall not vary from or take any proceeding or issue any order contrary to the Labor Law, the Multiple Dwelling Law, the building code or any other provision of law or any rule or decision of the board of standards and appeals.