New York Laws
Article 12 - Hotels and Boarding Houses
204-A - Safety Chain Latches Required.

ยง 204-a. Safety chain latches required. Every person, firm or
corporation engaged in the business of furnishing public lodging
accommodations in hotels, motels or motor courts shall install and
maintain, on the inside of each entrance door to every rental unit for
which there is a duplicate or master key which would afford entry to
said unit by one other than the occupant, a safety chain latch.