N.Y. Nav. Law § 35-b

§ 35-b. Markers for skin or scuba divers. 1. The commissioner is\nhereby authorized to make rules and regulations requiring the use of a\nred flag with a diagonal white bar to be displayed on the water or from\na boat by skin divers or scuba divers which would indicate underwater\ndiving and significantly mark their position in such waters. The\ncommissioner shall specify the size, shape, material of construction and\nmanner of placing such markers.\n 2. A violation of such rules and regulations so established pursuant\nto subdivision one herein, shall constitute an offense punishable by a\nfine not to exceed fifty dollars.\n