N.Y.C. Admin. Code § 28-105.4.1: § 28-105.4.1 Emergency work.

Work that would otherwise require a permit may be performed without a permit to the extent necessary to relieve an emergency condition. An application for a permit shall be submitted within 2 business days after the commencement of the emergency work and shall include written description of the emergency condition and the measures undertaken to mitigate the hazard. Emergency work may include but shall not be limited to:

1. Erection of sidewalk sheds, fences, or other similar structures to protect the public from an unsafe condition.

2. Stabilization of unsafe structural conditions.

3. Repair of gas leaks.

4. Repair or replacement of heating appliances or equipment servicing education or residential occupancies from October 1 through May 31.

5. Replacement of parts required for the operation of a standpipe or sprinkler system.

6. Repair of a plumbing system necessary to protect the public from an unsafe condition or to restore water service to a building or dwelling unit.