N.Y. Comp. Codes R. & Regs. tit. 17 § 2C.109
Option:
01 The SLIDES (NYW4-15) sign (see Sign Drawing SD-W12) may be used, as necessary, to warn of roadway sections where slides of soil, rock, or other material may obstruct the roadway or shoulder, or otherwise affect normal traffic flow.
Guidance:
02 The SLIDES sign should be removed when the condition stabilizes, or is corrected, and future incidents involving slides are considered unlikely.
03 The SLIDES sign should be supplemented with a Distance plaque (see Section 2C.55 ) where the roadway section is 1000 feet or longer. Additional SLIDES signs, supplemented with Distance plaques stating the distance to the end of the section, should be placed at suitable locations (for example, beyond intersections), and at appropriate intervals, in long sections. Where such additional sign is placed within 1000 feet of the end of the section, the Distance plaque should be omitted.
N.Y. Comp. Codes R. & Regs. Tit. 17 § 2C.109